cmd/devp2p: add discv4 test suite (#21163)

This adds a test suite for discovery v4. The test suite is a port of the Hive suite for
discovery, and will replace the current suite on Hive soon-ish. The tests can be
run locally with this command:

    devp2p discv4 test -remote enode//...
Co-authored-by: Felix Lange <fjl@twurst.com>

cmd/devp2p/discv4cmd.go

@@ -19,11 +19,14 @@ package main
 import (
 	"fmt"
 	"net"
+	"os"
 	"strings"
 	"time"
 
+	"github.com/ethereum/go-ethereum/cmd/devp2p/internal/v4test"
 	"github.com/ethereum/go-ethereum/common"
 	"github.com/ethereum/go-ethereum/crypto"
+	"github.com/ethereum/go-ethereum/internal/utesting"
 	"github.com/ethereum/go-ethereum/p2p/discover"
 	"github.com/ethereum/go-ethereum/p2p/enode"
 	"github.com/ethereum/go-ethereum/params"
@@ -40,6 +43,7 @@ var (
 			discv4ResolveCommand,
 			discv4ResolveJSONCommand,
 			discv4CrawlCommand,
+			discv4TestCommand,
 		},
 	}
 	discv4PingCommand = cli.Command{
@@ -74,6 +78,12 @@ var (
 		Action: discv4Crawl,
 		Flags:  []cli.Flag{bootnodesFlag, crawlTimeoutFlag},
 	}
+	discv4TestCommand = cli.Command{
+		Name:   "test",
+		Usage:  "Runs tests against a node",
+		Action: discv4Test,
+		Flags:  []cli.Flag{remoteEnodeFlag, testPatternFlag, testListen1Flag, testListen2Flag},
+	}
 )
 
 var (
@@ -98,6 +108,25 @@ var (
 		Usage: "Time limit for the crawl.",
 		Value: 30 * time.Minute,
 	}
+	remoteEnodeFlag = cli.StringFlag{
+		Name:   "remote",
+		Usage:  "Enode of the remote node under test",
+		EnvVar: "REMOTE_ENODE",
+	}
+	testPatternFlag = cli.StringFlag{
+		Name:  "run",
+		Usage: "Pattern of test suite(s) to run",
+	}
+	testListen1Flag = cli.StringFlag{
+		Name:  "listen1",
+		Usage: "IP address of the first tester",
+		Value: v4test.Listen1,
+	}
+	testListen2Flag = cli.StringFlag{
+		Name:  "listen2",
+		Usage: "IP address of the second tester",
+		Value: v4test.Listen2,
+	}
 )
 
 func discv4Ping(ctx *cli.Context) error {
@@ -184,6 +213,28 @@ func discv4Crawl(ctx *cli.Context) error {
 	return nil
 }
 
+func discv4Test(ctx *cli.Context) error {
+	// Configure test package globals.
+	if !ctx.IsSet(remoteEnodeFlag.Name) {
+		return fmt.Errorf("Missing -%v", remoteEnodeFlag.Name)
+	}
+	v4test.Remote = ctx.String(remoteEnodeFlag.Name)
+	v4test.Listen1 = ctx.String(testListen1Flag.Name)
+	v4test.Listen2 = ctx.String(testListen2Flag.Name)
+
+	// Filter and run test cases.
+	tests := v4test.AllTests
+	if ctx.IsSet(testPatternFlag.Name) {
+		tests = utesting.MatchTests(tests, ctx.String(testPatternFlag.Name))
+	}
+	results := utesting.RunTests(tests, os.Stdout)
+	if fails := utesting.CountFailures(results); fails > 0 {
+		return fmt.Errorf("%v/%v tests passed.", len(tests)-fails, len(tests))
+	}
+	fmt.Printf("%v/%v passed\n", len(tests), len(tests))
+	return nil
+}
+
 // startV4 starts an ephemeral discovery V4 node.
 func startV4(ctx *cli.Context) *discover.UDPv4 {
 	ln, config := makeDiscoveryConfig(ctx)

cmd/devp2p/internal/v4test/framework.go

+// Copyright 2020 The go-ethereum Authors
+// This file is part of go-ethereum.
+//
+// go-ethereum is free software: you can redistribute it and/or modify
+// it under the terms of the GNU General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+//
+// go-ethereum 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 General Public License for more details.
+//
+// You should have received a copy of the GNU General Public License
+// along with go-ethereum. If not, see <http://www.gnu.org/licenses/>.
+
+package v4test
+
+import (
+	"crypto/ecdsa"
+	"fmt"
+	"net"
+	"time"
+
+	"github.com/ethereum/go-ethereum/crypto"
+	"github.com/ethereum/go-ethereum/p2p/discover/v4wire"
+	"github.com/ethereum/go-ethereum/p2p/enode"
+)
+
+const waitTime = 300 * time.Millisecond
+
+type testenv struct {
+	l1, l2     net.PacketConn
+	key        *ecdsa.PrivateKey
+	remote     *enode.Node
+	remoteAddr *net.UDPAddr
+}
+
+func newTestEnv(remote string, listen1, listen2 string) *testenv {
+	l1, err := net.ListenPacket("udp", fmt.Sprintf("%v:0", listen1))
+	if err != nil {
+		panic(err)
+	}
+	l2, err := net.ListenPacket("udp", fmt.Sprintf("%v:0", listen2))
+	if err != nil {
+		panic(err)
+	}
+	key, err := crypto.GenerateKey()
+	if err != nil {
+		panic(err)
+	}
+	node, err := enode.Parse(enode.ValidSchemes, remote)
+	if err != nil {
+		panic(err)
+	}
+	if node.IP() == nil || node.UDP() == 0 {
+		var ip net.IP
+		var tcpPort, udpPort int
+		if ip = node.IP(); ip == nil {
+			ip = net.ParseIP("127.0.0.1")
+		}
+		if tcpPort = node.TCP(); tcpPort == 0 {
+			tcpPort = 30303
+		}
+		if udpPort = node.TCP(); udpPort == 0 {
+			udpPort = 30303
+		}
+		node = enode.NewV4(node.Pubkey(), ip, tcpPort, udpPort)
+	}
+	addr := &net.UDPAddr{IP: node.IP(), Port: node.UDP()}
+	return &testenv{l1, l2, key, node, addr}
+}
+
+func (te *testenv) close() {
+	te.l1.Close()
+	te.l2.Close()
+}
+
+func (te *testenv) send(c net.PacketConn, req v4wire.Packet) []byte {
+	packet, hash, err := v4wire.Encode(te.key, req)
+	if err != nil {
+		panic(fmt.Errorf("can't encode %v packet: %v", req.Name(), err))
+	}
+	if _, err := c.WriteTo(packet, te.remoteAddr); err != nil {
+		panic(fmt.Errorf("can't send %v: %v", req.Name(), err))
+	}
+	return hash
+}
+
+func (te *testenv) read(c net.PacketConn) (v4wire.Packet, []byte, error) {
+	buf := make([]byte, 2048)
+	if err := c.SetReadDeadline(time.Now().Add(waitTime)); err != nil {
+		return nil, nil, err
+	}
+	n, _, err := c.ReadFrom(buf)
+	if err != nil {
+		return nil, nil, err
+	}
+	p, _, hash, err := v4wire.Decode(buf[:n])
+	return p, hash, err
+}
+
+func (te *testenv) localEndpoint(c net.PacketConn) v4wire.Endpoint {
+	addr := c.LocalAddr().(*net.UDPAddr)
+	return v4wire.Endpoint{
+		IP:  addr.IP.To4(),
+		UDP: uint16(addr.Port),
+		TCP: 0,
+	}
+}
+
+func (te *testenv) remoteEndpoint() v4wire.Endpoint {
+	return v4wire.NewEndpoint(te.remoteAddr, 0)
+}
+
+func contains(ns []v4wire.Node, key v4wire.Pubkey) bool {
+	for _, n := range ns {
+		if n.ID == key {
+			return true
+		}
+	}
+	return false
+}

go.sum

@@ -207,6 +207,7 @@ golang.org/x/sync v0.0.0-20181108010431-42b317875d0f/go.mod h1:RxMgew5VJxzue5/jJ
 golang.org/x/sys v0.0.0-20180909124046-d0be0721c37e/go.mod h1:STP8DvDyc/dI5b8T5hshtkjS+E42TnysNCUPdjciGhY=
 golang.org/x/sys v0.0.0-20181107165924-66b7b1311ac8/go.mod h1:STP8DvDyc/dI5b8T5hshtkjS+E42TnysNCUPdjciGhY=
 golang.org/x/sys v0.0.0-20190215142949-d0b11bdaac8a/go.mod h1:STP8DvDyc/dI5b8T5hshtkjS+E42TnysNCUPdjciGhY=
+golang.org/x/sys v0.0.0-20190405154228-4b34438f7a67/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
 golang.org/x/sys v0.0.0-20190412213103-97732733099d/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
 golang.org/x/sys v0.0.0-20200323222414-85ca7c5b95cd h1:xhmwyvizuTgC2qz7ZlMluP20uW+C3Rm0FD/WLDX8884=
 golang.org/x/sys v0.0.0-20200323222414-85ca7c5b95cd/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=

internal/utesting/utesting.go

+// Copyright 2020 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 utesting provides a standalone replacement for package testing.
+//
+// This package exists because package testing cannot easily be embedded into a
+// standalone go program. It provides an API that mirrors the standard library
+// testing API.
+package utesting
+
+import (
+	"bytes"
+	"fmt"
+	"io"
+	"regexp"
+	"runtime"
+	"sync"
+	"time"
+)
+
+// Test represents a single test.
+type Test struct {
+	Name string
+	Fn   func(*T)
+}
+
+// Result is the result of a test execution.
+type Result struct {
+	Name     string
+	Failed   bool
+	Output   string
+	Duration time.Duration
+}
+
+// MatchTests returns the tests whose name matches a regular expression.
+func MatchTests(tests []Test, expr string) []Test {
+	var results []Test
+	re, err := regexp.Compile(expr)
+	if err != nil {
+		return nil
+	}
+	for _, test := range tests {
+		if re.MatchString(test.Name) {
+			results = append(results, test)
+		}
+	}
+	return results
+}
+
+// RunTests executes all given tests in order and returns their results.
+// If the report writer is non-nil, a test report is written to it in real time.
+func RunTests(tests []Test, report io.Writer) []Result {
+	results := make([]Result, len(tests))
+	for i, test := range tests {
+		start := time.Now()
+		results[i].Name = test.Name
+		results[i].Failed, results[i].Output = Run(test)
+		results[i].Duration = time.Since(start)
+		if report != nil {
+			printResult(results[i], report)
+		}
+	}
+	return results
+}
+
+func printResult(r Result, w io.Writer) {
+	pd := r.Duration.Truncate(100 * time.Microsecond)
+	if r.Failed {
+		fmt.Fprintf(w, "-- FAIL %s (%v)\n", r.Name, pd)
+		fmt.Fprintln(w, r.Output)
+	} else {
+		fmt.Fprintf(w, "-- OK %s (%v)\n", r.Name, pd)
+	}
+}
+
+// CountFailures returns the number of failed tests in the result slice.
+func CountFailures(rr []Result) int {
+	count := 0
+	for _, r := range rr {
+		if r.Failed {
+			count++
+		}
+	}
+	return count
+}
+
+// Run executes a single test.
+func Run(test Test) (bool, string) {
+	t := new(T)
+	done := make(chan struct{})
+	go func() {
+		defer close(done)
+		defer func() {
+			if err := recover(); err != nil {
+				buf := make([]byte, 4096)
+				i := runtime.Stack(buf, false)
+				t.Logf("panic: %v\n\n%s", err, buf[:i])
+				t.Fail()
+			}
+		}()
+		test.Fn(t)
+	}()
+	<-done
+	return t.failed, t.output.String()
+}
+
+// T is the value given to the test function. The test can signal failures
+// and log output by calling methods on this object.
+type T struct {
+	mu     sync.Mutex
+	failed bool
+	output bytes.Buffer
+}
+
+// FailNow marks the test as having failed and stops its execution by calling
+// runtime.Goexit (which then runs all deferred calls in the current goroutine).
+func (t *T) FailNow() {
+	t.Fail()
+	runtime.Goexit()
+}
+
+// Fail marks the test as having failed but continues execution.
+func (t *T) Fail() {
+	t.mu.Lock()
+	defer t.mu.Unlock()
+	t.failed = true
+}
+
+// Failed reports whether the test has failed.
+func (t *T) Failed() bool {
+	t.mu.Lock()
+	defer t.mu.Unlock()
+	return t.failed
+}
+
+// Log formats its arguments using default formatting, analogous to Println, and records
+// the text in the error log.
+func (t *T) Log(vs ...interface{}) {
+	t.mu.Lock()
+	defer t.mu.Unlock()
+	fmt.Fprintln(&t.output, vs...)
+}
+
+// Logf formats its arguments according to the format, analogous to Printf, and records
+// the text in the error log. A final newline is added if not provided.
+func (t *T) Logf(format string, vs ...interface{}) {
+	t.mu.Lock()
+	defer t.mu.Unlock()
+	if len(format) == 0 || format[len(format)-1] != '\n' {
+		format += "\n"
+	}
+	fmt.Fprintf(&t.output, format, vs...)
+}
+
+// Error is equivalent to Log followed by Fail.
+func (t *T) Error(vs ...interface{}) {
+	t.Log(vs...)
+	t.Fail()
+}
+
+// Errorf is equivalent to Logf followed by Fail.
+func (t *T) Errorf(format string, vs ...interface{}) {
+	t.Logf(format, vs...)
+	t.Fail()
+}
+
+// Fatal is equivalent to Log followed by FailNow.
+func (t *T) Fatal(vs ...interface{}) {
+	t.Log(vs...)
+	t.FailNow()
+}
+
+// Fatalf is equivalent to Logf followed by FailNow.
+func (t *T) Fatalf(format string, vs ...interface{}) {
+	t.Logf(format, vs...)
+	t.FailNow()
+}

internal/utesting/utesting_test.go

+// Copyright 2020 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 utesting
+
+import (
+	"strings"
+	"testing"
+)
+
+func TestTest(t *testing.T) {
+	tests := []Test{
+		{
+			Name: "successful test",
+			Fn:   func(t *T) {},
+		},
+		{
+			Name: "failing test",
+			Fn: func(t *T) {
+				t.Log("output")
+				t.Error("failed")
+			},
+		},
+		{
+			Name: "panicking test",
+			Fn: func(t *T) {
+				panic("oh no")
+			},
+		},
+	}
+	results := RunTests(tests, nil)
+
+	if results[0].Failed || results[0].Output != "" {
+		t.Fatalf("wrong result for successful test: %#v", results[0])
+	}
+	if !results[1].Failed || results[1].Output != "output\nfailed\n" {
+		t.Fatalf("wrong result for failing test: %#v", results[1])
+	}
+	if !results[2].Failed || !strings.HasPrefix(results[2].Output, "panic: oh no\n") {
+		t.Fatalf("wrong result for panicking test: %#v", results[2])
+	}
+}