Golang sha3.NewKeccak256函數代碼示例

// secrets is called after the handshake is completed.
// It extracts the connection secrets from the handshake values.
func (h *encHandshake) secrets(auth, authResp []byte) (secrets, error) {
	ecdheSecret, err := h.randomPrivKey.GenerateShared(h.remoteRandomPub, sskLen, sskLen)
	if err != nil {
		return secrets{}, err
	}

	// derive base secrets from ephemeral key agreement
	sharedSecret := crypto.Sha3(ecdheSecret, crypto.Sha3(h.respNonce, h.initNonce))
	aesSecret := crypto.Sha3(ecdheSecret, sharedSecret)
	s := secrets{
		RemoteID: h.remoteID,
		AES:      aesSecret,
		MAC:      crypto.Sha3(ecdheSecret, aesSecret),
		Token:    crypto.Sha3(sharedSecret),
	}

	// setup sha3 instances for the MACs
	mac1 := sha3.NewKeccak256()
	mac1.Write(xor(s.MAC, h.respNonce))
	mac1.Write(auth)
	mac2 := sha3.NewKeccak256()
	mac2.Write(xor(s.MAC, h.initNonce))
	mac2.Write(authResp)
	if h.initiator {
		s.EgressMAC, s.IngressMAC = mac1, mac2
	} else {
		s.EgressMAC, s.IngressMAC = mac2, mac1
	}

	return s, nil
}

func (dag *Dagger) Node(L uint64, i uint64) *big.Int {
	if L == i {
		return dag.hash
	}

	var m *big.Int
	if L == 9 {
		m = big.NewInt(16)
	} else {
		m = big.NewInt(3)
	}

	sha := sha3.NewKeccak256()
	sha.Reset()
	d := sha3.NewKeccak256()
	b := new(big.Int)
	ret := new(big.Int)

	for k := 0; k < int(m.Uint64()); k++ {
		d.Reset()
		d.Write(dag.hash.Bytes())
		d.Write(dag.xn.Bytes())
		d.Write(big.NewInt(int64(L)).Bytes())
		d.Write(big.NewInt(int64(i)).Bytes())
		d.Write(big.NewInt(int64(k)).Bytes())

		b.SetBytes(Sum(d))
		pk := b.Uint64() & ((1 << ((L - 1) * 3)) - 1)
		sha.Write(dag.Node(L-1, pk).Bytes())
	}

	ret.SetBytes(Sum(sha))

	return ret
}

func (dag *Dagger) Eval(N *big.Int) *big.Int {
	pow := common.BigPow(2, 26)
	dag.xn = pow.Div(N, pow)

	sha := sha3.NewKeccak256()
	sha.Reset()
	ret := new(big.Int)

	for k := 0; k < 4; k++ {
		d := sha3.NewKeccak256()
		b := new(big.Int)

		d.Reset()
		d.Write(dag.hash.Bytes())
		d.Write(dag.xn.Bytes())
		d.Write(N.Bytes())
		d.Write(big.NewInt(int64(k)).Bytes())

		b.SetBytes(Sum(d))
		pk := (b.Uint64() & 0x1ffffff)

		sha.Write(dag.Node(9, pk).Bytes())
	}

	return ret.SetBytes(Sum(sha))
}

func startTestServer(t *testing.T, pf newPeerHook) *Server {
	server := &Server{
		Name:        "test",
		MaxPeers:    10,
		ListenAddr:  "127.0.0.1:0",
		PrivateKey:  newkey(),
		newPeerHook: pf,
		setupFunc: func(fd net.Conn, prv *ecdsa.PrivateKey, our *protoHandshake, dial *discover.Node, keepconn func(discover.NodeID) bool) (*conn, error) {
			id := randomID()
			if !keepconn(id) {
				return nil, DiscAlreadyConnected
			}
			rw := newRlpxFrameRW(fd, secrets{
				MAC:        zero16,
				AES:        zero16,
				IngressMAC: sha3.NewKeccak256(),
				EgressMAC:  sha3.NewKeccak256(),
			})
			return &conn{
				MsgReadWriter:  rw,
				protoHandshake: &protoHandshake{ID: id, Version: baseProtocolVersion},
			}, nil
		},
	}
	if err := server.Start(); err != nil {
		t.Fatalf("Could not start server: %v", err)
	}
	return server
}

func TestRLPXFrameRW(t *testing.T) {
	var (
		aesSecret      = make([]byte, 16)
		macSecret      = make([]byte, 16)
		egressMACinit  = make([]byte, 32)
		ingressMACinit = make([]byte, 32)
	)
	for _, s := range [][]byte{aesSecret, macSecret, egressMACinit, ingressMACinit} {
		rand.Read(s)
	}
	conn := new(bytes.Buffer)

	s1 := secrets{
		AES:        aesSecret,
		MAC:        macSecret,
		EgressMAC:  sha3.NewKeccak256(),
		IngressMAC: sha3.NewKeccak256(),
	}
	s1.EgressMAC.Write(egressMACinit)
	s1.IngressMAC.Write(ingressMACinit)
	rw1 := newRLPXFrameRW(conn, s1)

	s2 := secrets{
		AES:        aesSecret,
		MAC:        macSecret,
		EgressMAC:  sha3.NewKeccak256(),
		IngressMAC: sha3.NewKeccak256(),
	}
	s2.EgressMAC.Write(ingressMACinit)
	s2.IngressMAC.Write(egressMACinit)
	rw2 := newRLPXFrameRW(conn, s2)

	// send some messages
	for i := 0; i < 10; i++ {
		// write message into conn buffer
		wmsg := []interface{}{"foo", "bar", strings.Repeat("test", i)}
		err := Send(rw1, uint64(i), wmsg)
		if err != nil {
			t.Fatalf("WriteMsg error (i=%d): %v", i, err)
		}

		// read message that rw1 just wrote
		msg, err := rw2.ReadMsg()
		if err != nil {
			t.Fatalf("ReadMsg error (i=%d): %v", i, err)
		}
		if msg.Code != uint64(i) {
			t.Fatalf("msg code mismatch: got %d, want %d", msg.Code, i)
		}
		payload, _ := ioutil.ReadAll(msg.Payload)
		wantPayload, _ := rlp.EncodeToBytes(wmsg)
		if !bytes.Equal(payload, wantPayload) {
			t.Fatalf("msg payload mismatch:\ngot  %x\nwant %x", payload, wantPayload)
		}
	}
}

func newTestTransport(id discover.NodeID, fd net.Conn) transport {
	wrapped := newRLPX(fd).(*rlpx)
	wrapped.rw = newRLPXFrameRW(fd, secrets{
		MAC:        zero16,
		AES:        zero16,
		IngressMAC: sha3.NewKeccak256(),
		EgressMAC:  sha3.NewKeccak256(),
	})
	return &testTransport{id: id, rlpx: wrapped}
}

// VerifyProof checks merkle proofs. The given proof must contain the
// value for key in a trie with the given root hash. VerifyProof
// returns an error if the proof contains invalid trie nodes or the
// wrong value.
func VerifyProof(rootHash common.Hash, key []byte, proof []rlp.RawValue) (value []byte, err error) {
	key = compactHexDecode(key)
	sha := sha3.NewKeccak256()
	wantHash := rootHash.Bytes()
	for i, buf := range proof {
		sha.Reset()
		sha.Write(buf)
		if !bytes.Equal(sha.Sum(nil), wantHash) {
			return nil, fmt.Errorf("bad proof node %d: hash mismatch", i)
		}
		n, err := decodeNode(buf)
		if err != nil {
			return nil, fmt.Errorf("bad proof node %d: %v", i, err)
		}
		keyrest, cld := get(n, key)
		switch cld := cld.(type) {
		case nil:
			if i != len(proof)-1 {
				return nil, fmt.Errorf("key mismatch at proof node %d", i)
			} else {
				// The trie doesn't contain the key.
				return nil, nil
			}
		case hashNode:
			key = keyrest
			wantHash = cld
		case valueNode:
			if i != len(proof)-1 {
				return nil, errors.New("additional nodes at end of proof")
			}
			return cld, nil
		}
	}
	return nil, errors.New("unexpected end of proof")
}

func Sha3(data ...[]byte) []byte {
	d := sha3.NewKeccak256()
	for _, b := range data {
		d.Write(b)
	}
	return d.Sum(nil)
}

// Tests block header storage and retrieval operations.
func TestHeaderStorage(t *testing.T) {
	db, _ := ethdb.NewMemDatabase()

	// Create a test header to move around the database and make sure it's really new
	header := &types.Header{Extra: []byte("test header")}
	if entry := GetHeader(db, header.Hash()); entry != nil {
		t.Fatalf("Non existent header returned: %v", entry)
	}
	// Write and verify the header in the database
	if err := WriteHeader(db, header); err != nil {
		t.Fatalf("Failed to write header into database: %v", err)
	}
	if entry := GetHeader(db, header.Hash()); entry == nil {
		t.Fatalf("Stored header not found")
	} else if entry.Hash() != header.Hash() {
		t.Fatalf("Retrieved header mismatch: have %v, want %v", entry, header)
	}
	if entry := GetHeaderRLP(db, header.Hash()); entry == nil {
		t.Fatalf("Stored header RLP not found")
	} else {
		hasher := sha3.NewKeccak256()
		hasher.Write(entry)

		if hash := common.BytesToHash(hasher.Sum(nil)); hash != header.Hash() {
			t.Fatalf("Retrieved RLP header mismatch: have %v, want %v", entry, header)
		}
	}
	// Delete the header and verify the execution
	DeleteHeader(db, header.Hash())
	if entry := GetHeader(db, header.Hash()); entry != nil {
		t.Fatalf("Deleted header returned: %v", entry)
	}
}

func Sha3Hash(data ...[]byte) (h common.Hash) {
	d := sha3.NewKeccak256()
	for _, b := range data {
		d.Write(b)
	}
	d.Sum(h[:0])
	return h
}

func (t *SecureTrie) hashKey(key []byte) []byte {
	if t.hash == nil {
		t.hash = sha3.NewKeccak256()
		t.hashKeyBuf = make([]byte, 32)
	}
	t.hash.Reset()
	t.hash.Write(key)
	t.hashKeyBuf = t.hash.Sum(t.hashKeyBuf[:0])
	return t.hashKeyBuf
}

func verify(hash common.Hash, diff *big.Int, nonce uint64) bool {
	sha := sha3.NewKeccak256()
	n := make([]byte, 8)
	binary.PutUvarint(n, nonce)
	sha.Write(n)
	sha.Write(hash[:])
	verification := new(big.Int).Div(common.BigPow(2, 256), diff)
	res := common.BigD(sha.Sum(nil))
	return res.Cmp(verification) <= 0
}

// Tests block body storage and retrieval operations.
func TestBodyStorage(t *testing.T) {
	db, _ := ethdb.NewMemDatabase()

	// Create a test body to move around the database and make sure it's really new
	body := &types.Body{Uncles: []*types.Header{{Extra: []byte("test header")}}}

	hasher := sha3.NewKeccak256()
	rlp.Encode(hasher, body)
	hash := common.BytesToHash(hasher.Sum(nil))

	if entry := GetBody(db, hash); entry != nil {
		t.Fatalf("Non existent body returned: %v", entry)
	}
	// Write and verify the body in the database
	if err := WriteBody(db, hash, body); err != nil {
		t.Fatalf("Failed to write body into database: %v", err)
	}
	if entry := GetBody(db, hash); entry == nil {
		t.Fatalf("Stored body not found")
	} else if types.DeriveSha(types.Transactions(entry.Transactions)) != types.DeriveSha(types.Transactions(body.Transactions)) || types.CalcUncleHash(entry.Uncles) != types.CalcUncleHash(body.Uncles) {
		t.Fatalf("Retrieved body mismatch: have %v, want %v", entry, body)
	}
	if entry := GetBodyRLP(db, hash); entry == nil {
		t.Fatalf("Stored body RLP not found")
	} else {
		hasher := sha3.NewKeccak256()
		hasher.Write(entry)

		if calc := common.BytesToHash(hasher.Sum(nil)); calc != hash {
			t.Fatalf("Retrieved RLP body mismatch: have %v, want %v", entry, body)
		}
	}
	// Delete the body and verify the execution
	DeleteBody(db, hash)
	if entry := GetBody(db, hash); entry != nil {
		t.Fatalf("Deleted body returned: %v", entry)
	}
}

func rlpHash(x interface{}) (h common.Hash) {
	hw := sha3.NewKeccak256()
	rlp.Encode(hw, x)
	hw.Sum(h[:0])
	return h
}

// TODO: copied from crypto.go , move to sha3 package?
func Sha3(data []byte) []byte {
	d := sha3.NewKeccak256()
	d.Write(data)

	return d.Sum(nil)
}