dex: redesign p2p network topology

- Let p2p server support direct connection and group connection.
- Introduce node meta table to maintain IP of all nodes in node set,
  in memory and let nodes in the network can sync this table.
- Let peerSet able to manage direct connections to notary set and dkg set.

The mechanism to refresh the network topology when configuration round
change is not done yet.

1 files changed, 445 insertions, 0 deletions

diff --git a/dex/handler_test.go b/dex/handler_test.go
new file mode 100644
index 000000000..981362bb5
--- /dev/null
+++ b/dex/handler_test.go
@@ -0,0 +1,445 @@
+// Copyright 2015 The go-ethereum Authors
+// This file is part of the go-ethereum library.
+//
+// The go-ethereum 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 go-ethereum 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 go-ethereum library. If not, see <http://www.gnu.org/licenses/>.
+
+package dex
+
+import (
+	"math"
+	"math/big"
+	"math/rand"
+	"testing"
+
+	"github.com/dexon-foundation/dexon/common"
+	"github.com/dexon-foundation/dexon/core"
+	"github.com/dexon-foundation/dexon/core/state"
+	"github.com/dexon-foundation/dexon/core/types"
+	"github.com/dexon-foundation/dexon/crypto"
+	"github.com/dexon-foundation/dexon/eth/downloader"
+	"github.com/dexon-foundation/dexon/ethdb"
+	"github.com/dexon-foundation/dexon/p2p"
+	"github.com/dexon-foundation/dexon/params"
+)
+
+// Tests that protocol versions and modes of operations are matched up properly.
+func TestProtocolCompatibility(t *testing.T) {
+	// Define the compatibility chart
+	tests := []struct {
+		version    uint
+		mode       downloader.SyncMode
+		compatible bool
+	}{
+		{61, downloader.FullSync, true}, {62, downloader.FullSync, true}, {63, downloader.FullSync, true},
+		{61, downloader.FastSync, true}, {62, downloader.FastSync, true}, {63, downloader.FastSync, true},
+	}
+	// Make sure anything we screw up is restored
+	backup := ProtocolVersions
+	defer func() { ProtocolVersions = backup }()
+
+	// Try all available compatibility configs and check for errors
+	for i, tt := range tests {
+		ProtocolVersions = []uint{tt.version}
+
+		pm, _, err := newTestProtocolManager(tt.mode, 0, nil, nil)
+		if pm != nil {
+			defer pm.Stop()
+		}
+		if (err == nil && !tt.compatible) || (err != nil && tt.compatible) {
+			t.Errorf("test %d: compatibility mismatch: have error %v, want compatibility %v", i, err, tt.compatible)
+		}
+	}
+}
+
+// Tests that block headers can be retrieved from a remote chain based on user queries.
+func TestGetBlockHeaders62(t *testing.T) { testGetBlockHeaders(t, 62) }
+func TestGetBlockHeaders63(t *testing.T) { testGetBlockHeaders(t, 63) }
+
+func testGetBlockHeaders(t *testing.T, protocol int) {
+	pm, _ := newTestProtocolManagerMust(t, downloader.FullSync, downloader.MaxHashFetch+15, nil, nil)
+	peer, _ := newTestPeer("peer", protocol, pm, true)
+	defer peer.close()
+
+	// Create a "random" unknown hash for testing
+	var unknown common.Hash
+	for i := range unknown {
+		unknown[i] = byte(i)
+	}
+	// Create a batch of tests for various scenarios
+	limit := uint64(downloader.MaxHeaderFetch)
+	tests := []struct {
+		query  *getBlockHeadersData // The query to execute for header retrieval
+		expect []common.Hash        // The hashes of the block whose headers are expected
+	}{
+		// A single random block should be retrievable by hash and number too
+		{
+			&getBlockHeadersData{Origin: hashOrNumber{Hash: pm.blockchain.GetBlockByNumber(limit / 2).Hash()}, Amount: 1},
+			[]common.Hash{pm.blockchain.GetBlockByNumber(limit / 2).Hash()},
+		}, {
+			&getBlockHeadersData{Origin: hashOrNumber{Number: limit / 2}, Amount: 1},
+			[]common.Hash{pm.blockchain.GetBlockByNumber(limit / 2).Hash()},
+		},
+		// Multiple headers should be retrievable in both directions
+		{
+			&getBlockHeadersData{Origin: hashOrNumber{Number: limit / 2}, Amount: 3},
+			[]common.Hash{
+				pm.blockchain.GetBlockByNumber(limit / 2).Hash(),
+				pm.blockchain.GetBlockByNumber(limit/2 + 1).Hash(),
+				pm.blockchain.GetBlockByNumber(limit/2 + 2).Hash(),
+			},
+		}, {
+			&getBlockHeadersData{Origin: hashOrNumber{Number: limit / 2}, Amount: 3, Reverse: true},
+			[]common.Hash{
+				pm.blockchain.GetBlockByNumber(limit / 2).Hash(),
+				pm.blockchain.GetBlockByNumber(limit/2 - 1).Hash(),
+				pm.blockchain.GetBlockByNumber(limit/2 - 2).Hash(),
+			},
+		},
+		// Multiple headers with skip lists should be retrievable
+		{
+			&getBlockHeadersData{Origin: hashOrNumber{Number: limit / 2}, Skip: 3, Amount: 3},
+			[]common.Hash{
+				pm.blockchain.GetBlockByNumber(limit / 2).Hash(),
+				pm.blockchain.GetBlockByNumber(limit/2 + 4).Hash(),
+				pm.blockchain.GetBlockByNumber(limit/2 + 8).Hash(),
+			},
+		}, {
+			&getBlockHeadersData{Origin: hashOrNumber{Number: limit / 2}, Skip: 3, Amount: 3, Reverse: true},
+			[]common.Hash{
+				pm.blockchain.GetBlockByNumber(limit / 2).Hash(),
+				pm.blockchain.GetBlockByNumber(limit/2 - 4).Hash(),
+				pm.blockchain.GetBlockByNumber(limit/2 - 8).Hash(),
+			},
+		},
+		// The chain endpoints should be retrievable
+		{
+			&getBlockHeadersData{Origin: hashOrNumber{Number: 0}, Amount: 1},
+			[]common.Hash{pm.blockchain.GetBlockByNumber(0).Hash()},
+		}, {
+			&getBlockHeadersData{Origin: hashOrNumber{Number: pm.blockchain.CurrentBlock().NumberU64()}, Amount: 1},
+			[]common.Hash{pm.blockchain.CurrentBlock().Hash()},
+		},
+		// Ensure protocol limits are honored
+		{
+			&getBlockHeadersData{Origin: hashOrNumber{Number: pm.blockchain.CurrentBlock().NumberU64() - 1}, Amount: limit + 10, Reverse: true},
+			pm.blockchain.GetBlockHashesFromHash(pm.blockchain.CurrentBlock().Hash(), limit),
+		},
+		// Check that requesting more than available is handled gracefully
+		{
+			&getBlockHeadersData{Origin: hashOrNumber{Number: pm.blockchain.CurrentBlock().NumberU64() - 4}, Skip: 3, Amount: 3},
+			[]common.Hash{
+				pm.blockchain.GetBlockByNumber(pm.blockchain.CurrentBlock().NumberU64() - 4).Hash(),
+				pm.blockchain.GetBlockByNumber(pm.blockchain.CurrentBlock().NumberU64()).Hash(),
+			},
+		}, {
+			&getBlockHeadersData{Origin: hashOrNumber{Number: 4}, Skip: 3, Amount: 3, Reverse: true},
+			[]common.Hash{
+				pm.blockchain.GetBlockByNumber(4).Hash(),
+				pm.blockchain.GetBlockByNumber(0).Hash(),
+			},
+		},
+		// Check that requesting more than available is handled gracefully, even if mid skip
+		{
+			&getBlockHeadersData{Origin: hashOrNumber{Number: pm.blockchain.CurrentBlock().NumberU64() - 4}, Skip: 2, Amount: 3},
+			[]common.Hash{
+				pm.blockchain.GetBlockByNumber(pm.blockchain.CurrentBlock().NumberU64() - 4).Hash(),
+				pm.blockchain.GetBlockByNumber(pm.blockchain.CurrentBlock().NumberU64() - 1).Hash(),
+			},
+		}, {
+			&getBlockHeadersData{Origin: hashOrNumber{Number: 4}, Skip: 2, Amount: 3, Reverse: true},
+			[]common.Hash{
+				pm.blockchain.GetBlockByNumber(4).Hash(),
+				pm.blockchain.GetBlockByNumber(1).Hash(),
+			},
+		},
+		// Check a corner case where requesting more can iterate past the endpoints
+		{
+			&getBlockHeadersData{Origin: hashOrNumber{Number: 2}, Amount: 5, Reverse: true},
+			[]common.Hash{
+				pm.blockchain.GetBlockByNumber(2).Hash(),
+				pm.blockchain.GetBlockByNumber(1).Hash(),
+				pm.blockchain.GetBlockByNumber(0).Hash(),
+			},
+		},
+		// Check a corner case where skipping overflow loops back into the chain start
+		{
+			&getBlockHeadersData{Origin: hashOrNumber{Hash: pm.blockchain.GetBlockByNumber(3).Hash()}, Amount: 2, Reverse: false, Skip: math.MaxUint64 - 1},
+			[]common.Hash{
+				pm.blockchain.GetBlockByNumber(3).Hash(),
+			},
+		},
+		// Check a corner case where skipping overflow loops back to the same header
+		{
+			&getBlockHeadersData{Origin: hashOrNumber{Hash: pm.blockchain.GetBlockByNumber(1).Hash()}, Amount: 2, Reverse: false, Skip: math.MaxUint64},
+			[]common.Hash{
+				pm.blockchain.GetBlockByNumber(1).Hash(),
+			},
+		},
+		// Check that non existing headers aren't returned
+		{
+			&getBlockHeadersData{Origin: hashOrNumber{Hash: unknown}, Amount: 1},
+			[]common.Hash{},
+		}, {
+			&getBlockHeadersData{Origin: hashOrNumber{Number: pm.blockchain.CurrentBlock().NumberU64() + 1}, Amount: 1},
+			[]common.Hash{},
+		},
+	}
+	// Run each of the tests and verify the results against the chain
+	for i, tt := range tests {
+		// Collect the headers to expect in the response
+		headers := []*types.Header{}
+		for _, hash := range tt.expect {
+			headers = append(headers, pm.blockchain.GetBlockByHash(hash).Header())
+		}
+		// Send the hash request and verify the response
+		p2p.Send(peer.app, 0x03, tt.query)
+		if err := p2p.ExpectMsg(peer.app, 0x04, headers); err != nil {
+			t.Errorf("test %d: headers mismatch: %v", i, err)
+		}
+		// If the test used number origins, repeat with hashes as the too
+		if tt.query.Origin.Hash == (common.Hash{}) {
+			if origin := pm.blockchain.GetBlockByNumber(tt.query.Origin.Number); origin != nil {
+				tt.query.Origin.Hash, tt.query.Origin.Number = origin.Hash(), 0
+
+				p2p.Send(peer.app, 0x03, tt.query)
+				if err := p2p.ExpectMsg(peer.app, 0x04, headers); err != nil {
+					t.Errorf("test %d: headers mismatch: %v", i, err)
+				}
+			}
+		}
+	}
+}
+
+// Tests that block contents can be retrieved from a remote chain based on their hashes.
+func TestGetBlockBodies62(t *testing.T) { testGetBlockBodies(t, 62) }
+func TestGetBlockBodies63(t *testing.T) { testGetBlockBodies(t, 63) }
+
+func testGetBlockBodies(t *testing.T, protocol int) {
+	pm, _ := newTestProtocolManagerMust(t, downloader.FullSync, downloader.MaxBlockFetch+15, nil, nil)
+	peer, _ := newTestPeer("peer", protocol, pm, true)
+	defer peer.close()
+
+	// Create a batch of tests for various scenarios
+	limit := downloader.MaxBlockFetch
+	tests := []struct {
+		random    int           // Number of blocks to fetch randomly from the chain
+		explicit  []common.Hash // Explicitly requested blocks
+		available []bool        // Availability of explicitly requested blocks
+		expected  int           // Total number of existing blocks to expect
+	}{
+		{1, nil, nil, 1},                                                         // A single random block should be retrievable
+		{10, nil, nil, 10},                                                       // Multiple random blocks should be retrievable
+		{limit, nil, nil, limit},                                                 // The maximum possible blocks should be retrievable
+		{limit + 1, nil, nil, limit},                                             // No more than the possible block count should be returned
+		{0, []common.Hash{pm.blockchain.Genesis().Hash()}, []bool{true}, 1},      // The genesis block should be retrievable
+		{0, []common.Hash{pm.blockchain.CurrentBlock().Hash()}, []bool{true}, 1}, // The chains head block should be retrievable
+		{0, []common.Hash{{}}, []bool{false}, 0},                                 // A non existent block should not be returned
+
+		// Existing and non-existing blocks interleaved should not cause problems
+		{0, []common.Hash{
+			{},
+			pm.blockchain.GetBlockByNumber(1).Hash(),
+			{},
+			pm.blockchain.GetBlockByNumber(10).Hash(),
+			{},
+			pm.blockchain.GetBlockByNumber(100).Hash(),
+			{},
+		}, []bool{false, true, false, true, false, true, false}, 3},
+	}
+	// Run each of the tests and verify the results against the chain
+	for i, tt := range tests {
+		// Collect the hashes to request, and the response to expect
+		hashes, seen := []common.Hash{}, make(map[int64]bool)
+		bodies := []*blockBody{}
+
+		for j := 0; j < tt.random; j++ {
+			for {
+				num := rand.Int63n(int64(pm.blockchain.CurrentBlock().NumberU64()))
+				if !seen[num] {
+					seen[num] = true
+
+					block := pm.blockchain.GetBlockByNumber(uint64(num))
+					hashes = append(hashes, block.Hash())
+					if len(bodies) < tt.expected {
+						bodies = append(bodies, &blockBody{Transactions: block.Transactions(), Uncles: block.Uncles()})
+					}
+					break
+				}
+			}
+		}
+		for j, hash := range tt.explicit {
+			hashes = append(hashes, hash)
+			if tt.available[j] && len(bodies) < tt.expected {
+				block := pm.blockchain.GetBlockByHash(hash)
+				bodies = append(bodies, &blockBody{Transactions: block.Transactions(), Uncles: block.Uncles()})
+			}
+		}
+		// Send the hash request and verify the response
+		p2p.Send(peer.app, 0x05, hashes)
+		if err := p2p.ExpectMsg(peer.app, 0x06, bodies); err != nil {
+			t.Errorf("test %d: bodies mismatch: %v", i, err)
+		}
+	}
+}
+
+// Tests that the node state database can be retrieved based on hashes.
+func TestGetNodeData63(t *testing.T) { testGetNodeData(t, 63) }
+
+func testGetNodeData(t *testing.T, protocol int) {
+	// Define three accounts to simulate transactions with
+	acc1Key, _ := crypto.HexToECDSA("8a1f9a8f95be41cd7ccb6168179afb4504aefe388d1e14474d32c45c72ce7b7a")
+	acc2Key, _ := crypto.HexToECDSA("49a7b37aa6f6645917e7b807e9d1c00d4fa71f18343b0d4122a4d2df64dd6fee")
+	acc1Addr := crypto.PubkeyToAddress(acc1Key.PublicKey)
+	acc2Addr := crypto.PubkeyToAddress(acc2Key.PublicKey)
+
+	signer := types.HomesteadSigner{}
+	// Create a chain generator with some simple transactions (blatantly stolen from @fjl/chain_markets_test)
+	generator := func(i int, block *core.BlockGen) {
+		switch i {
+		case 0:
+			// In block 1, the test bank sends account #1 some ether.
+			tx, _ := types.SignTx(types.NewTransaction(block.TxNonce(testBank), acc1Addr, big.NewInt(10000), params.TxGas, nil, nil), signer, testBankKey)
+			block.AddTx(tx)
+		case 1:
+			// In block 2, the test bank sends some more ether to account #1.
+			// acc1Addr passes it on to account #2.
+			tx1, _ := types.SignTx(types.NewTransaction(block.TxNonce(testBank), acc1Addr, big.NewInt(1000), params.TxGas, nil, nil), signer, testBankKey)
+			tx2, _ := types.SignTx(types.NewTransaction(block.TxNonce(acc1Addr), acc2Addr, big.NewInt(1000), params.TxGas, nil, nil), signer, acc1Key)
+			block.AddTx(tx1)
+			block.AddTx(tx2)
+		case 2:
+			// Block 3 is empty but was mined by account #2.
+			block.SetCoinbase(acc2Addr)
+			block.SetExtra([]byte("yeehaw"))
+		case 3:
+			// Block 4 includes blocks 2 and 3 as uncle headers (with modified extra data).
+			b2 := block.PrevBlock(1).Header()
+			b2.Extra = []byte("foo")
+			block.AddUncle(b2)
+			b3 := block.PrevBlock(2).Header()
+			b3.Extra = []byte("foo")
+			block.AddUncle(b3)
+		}
+	}
+	// Assemble the test environment
+	pm, db := newTestProtocolManagerMust(t, downloader.FullSync, 4, generator, nil)
+	peer, _ := newTestPeer("peer", protocol, pm, true)
+	defer peer.close()
+
+	// Fetch for now the entire chain db
+	hashes := []common.Hash{}
+	for _, key := range db.Keys() {
+		if len(key) == len(common.Hash{}) {
+			hashes = append(hashes, common.BytesToHash(key))
+		}
+	}
+	p2p.Send(peer.app, 0x0d, hashes)
+	msg, err := peer.app.ReadMsg()
+	if err != nil {
+		t.Fatalf("failed to read node data response: %v", err)
+	}
+	if msg.Code != 0x0e {
+		t.Fatalf("response packet code mismatch: have %x, want %x", msg.Code, 0x0c)
+	}
+	var data [][]byte
+	if err := msg.Decode(&data); err != nil {
+		t.Fatalf("failed to decode response node data: %v", err)
+	}
+	// Verify that all hashes correspond to the requested data, and reconstruct a state tree
+	for i, want := range hashes {
+		if hash := crypto.Keccak256Hash(data[i]); hash != want {
+			t.Errorf("data hash mismatch: have %x, want %x", hash, want)
+		}
+	}
+	statedb := ethdb.NewMemDatabase()
+	for i := 0; i < len(data); i++ {
+		statedb.Put(hashes[i].Bytes(), data[i])
+	}
+	accounts := []common.Address{testBank, acc1Addr, acc2Addr}
+	for i := uint64(0); i <= pm.blockchain.CurrentBlock().NumberU64(); i++ {
+		trie, _ := state.New(pm.blockchain.GetBlockByNumber(i).Root(), state.NewDatabase(statedb))
+
+		for j, acc := range accounts {
+			state, _ := pm.blockchain.State()
+			bw := state.GetBalance(acc)
+			bh := trie.GetBalance(acc)
+
+			if (bw != nil && bh == nil) || (bw == nil && bh != nil) {
+				t.Errorf("test %d, account %d: balance mismatch: have %v, want %v", i, j, bh, bw)
+			}
+			if bw != nil && bh != nil && bw.Cmp(bw) != 0 {
+				t.Errorf("test %d, account %d: balance mismatch: have %v, want %v", i, j, bh, bw)
+			}
+		}
+	}
+}
+
+// Tests that the transaction receipts can be retrieved based on hashes.
+func TestGetReceipt63(t *testing.T) { testGetReceipt(t, 63) }
+
+func testGetReceipt(t *testing.T, protocol int) {
+	// Define three accounts to simulate transactions with
+	acc1Key, _ := crypto.HexToECDSA("8a1f9a8f95be41cd7ccb6168179afb4504aefe388d1e14474d32c45c72ce7b7a")
+	acc2Key, _ := crypto.HexToECDSA("49a7b37aa6f6645917e7b807e9d1c00d4fa71f18343b0d4122a4d2df64dd6fee")
+	acc1Addr := crypto.PubkeyToAddress(acc1Key.PublicKey)
+	acc2Addr := crypto.PubkeyToAddress(acc2Key.PublicKey)
+
+	signer := types.HomesteadSigner{}
+	// Create a chain generator with some simple transactions (blatantly stolen from @fjl/chain_markets_test)
+	generator := func(i int, block *core.BlockGen) {
+		switch i {
+		case 0:
+			// In block 1, the test bank sends account #1 some ether.
+			tx, _ := types.SignTx(types.NewTransaction(block.TxNonce(testBank), acc1Addr, big.NewInt(10000), params.TxGas, nil, nil), signer, testBankKey)
+			block.AddTx(tx)
+		case 1:
+			// In block 2, the test bank sends some more ether to account #1.
+			// acc1Addr passes it on to account #2.
+			tx1, _ := types.SignTx(types.NewTransaction(block.TxNonce(testBank), acc1Addr, big.NewInt(1000), params.TxGas, nil, nil), signer, testBankKey)
+			tx2, _ := types.SignTx(types.NewTransaction(block.TxNonce(acc1Addr), acc2Addr, big.NewInt(1000), params.TxGas, nil, nil), signer, acc1Key)
+			block.AddTx(tx1)
+			block.AddTx(tx2)
+		case 2:
+			// Block 3 is empty but was mined by account #2.
+			block.SetCoinbase(acc2Addr)
+			block.SetExtra([]byte("yeehaw"))
+		case 3:
+			// Block 4 includes blocks 2 and 3 as uncle headers (with modified extra data).
+			b2 := block.PrevBlock(1).Header()
+			b2.Extra = []byte("foo")
+			block.AddUncle(b2)
+			b3 := block.PrevBlock(2).Header()
+			b3.Extra = []byte("foo")
+			block.AddUncle(b3)
+		}
+	}
+	// Assemble the test environment
+	pm, _ := newTestProtocolManagerMust(t, downloader.FullSync, 4, generator, nil)
+	peer, _ := newTestPeer("peer", protocol, pm, true)
+	defer peer.close()
+
+	// Collect the hashes to request, and the response to expect
+	hashes, receipts := []common.Hash{}, []types.Receipts{}
+	for i := uint64(0); i <= pm.blockchain.CurrentBlock().NumberU64(); i++ {
+		block := pm.blockchain.GetBlockByNumber(i)
+
+		hashes = append(hashes, block.Hash())
+		receipts = append(receipts, pm.blockchain.GetReceiptsByHash(block.Hash()))
+	}
+	// Send the hash request and verify the response
+	p2p.Send(peer.app, 0x0f, hashes)
+	if err := p2p.ExpectMsg(peer.app, 0x10, receipts); err != nil {
+		t.Errorf("receipts mismatch: %v", err)
+	}
+}