// Copyright 2016 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 discv5
import (
"crypto/ecdsa"
"fmt"
"math/rand"
"net"
"reflect"
"testing"
"testing/quick"
"time"
"github.com/ethereum/go-ethereum/common"
"github.com/ethereum/go-ethereum/crypto"
)
type nullTransport struct{}
func (nullTransport) sendPing(remote *Node, remoteAddr *net.UDPAddr) []byte { return []byte{1} }
func (nullTransport) sendPong(remote *Node, pingHash []byte) {}
func (nullTransport) sendFindnode(remote *Node, target NodeID) {}
func (nullTransport) sendNeighbours(remote *Node, nodes []*Node) {}
func (nullTransport) localAddr() *net.UDPAddr { return new(net.UDPAddr) }
func (nullTransport) Close() {}
// func TestTable_pingReplace(t *testing.T) {
// doit := func(newNodeIsResponding, lastInBucketIsResponding bool) {
// transport := newPingRecorder()
// tab, _ := newTable(transport, NodeID{}, &net.UDPAddr{})
// defer tab.Close()
// pingSender := NewNode(MustHexID("a502af0f59b2aab7746995408c79e9ca312d2793cc997e44fc55eda62f0150bbb8c59a6f9269ba3a081518b62699ee807c7c19c20125ddfccca872608af9e370"), net.IP{}, 99, 99)
//
// // fill up the sender's bucket.
// last := fillBucket(tab, 253)
//
// // this call to bond should replace the last node
// // in its bucket if the node is not responding.
// transport.responding[last.ID] = lastInBucketIsResponding
// transport.responding[pingSender.ID] = newNodeIsResponding
// tab.bond(true, pingSender.ID, &net.UDPAddr{}, 0)
//
// // first ping goes to sender (bonding pingback)
// if !transport.pinged[pingSender.ID] {
// t.Error("table did not ping back sender")
// }
// if newNodeIsResponding {
// // second ping goes to oldest node in bucket
// // to see whether it is still alive.
// if !transport.pinged[last.ID] {
// t.Error("table did not ping last node in bucket")
// }
// }
//
// tab.mutex.Lock()
// defer tab.mutex.Unlock()
// if l := len(tab.buckets[253].entries); l != bucketSize {
// t.Errorf("wrong bucket size after bond: got %d, want %d", l, bucketSize)
// }
//
// if lastInBucketIsResponding || !newNodeIsResponding {
// if !contains(tab.buckets[253].entries, last.ID) {
// t.Error("last entry was removed")
// }
// if contains(tab.buckets[253].entries, pingSender.ID) {
// t.Error("new entry was added")
// }
// } else {
// if contains(tab.buckets[253].entries, last.ID) {
// t.Error("last entry was not removed")
// }
// if !contains(tab.buckets[253].entries, pingSender.ID) {
// t.Error("new entry was not added")
// }
// }
// }
//
// doit(true, true)
// doit(false, true)
// doit(true, false)
// doit(false, false)
// }
func TestBucket_bumpNoDuplicates(t *testing.T) {
t.Parallel()
cfg := &quick.Config{
MaxCount: 1000,
Rand: rand.New(rand.NewSource(time.Now().Unix())),
Values: func(args []reflect.Value, rand *rand.Rand) {
// generate a random list of nodes. this will be the content of the bucket.
n := rand.Intn(bucketSize-1) + 1
nodes := make([]*Node, n)
for i := range nodes {
nodes[i] = nodeAtDistance(common.Hash{}, 200)
}
args[0] = reflect.ValueOf(nodes)
// generate random bump positions.
bumps := make([]int, rand.Intn(100))
for i := range bumps {
bumps[i] = rand.Intn(len(nodes))
}
args[1] = reflect.ValueOf(bumps)
},
}
prop := func(nodes []*Node, bumps []int) (ok bool) {
b := &bucket{entries: make([]*Node, len(nodes))}
copy(b.entries, nodes)
for i, pos := range bumps {
b.bump(b.entries[pos])
if hasDuplicates(b.entries) {
t.Logf("bucket has duplicates after %d/%d bumps:", i+1, len(bumps))
for _, n := range b.entries {
t.Logf(" %p", n)
}
return false
}
}
return true
}
if err := quick.Check(prop, cfg); err != nil {
t.Error(err)
}
}
// fillBucket inserts nodes into the given bucket until
// it is full. The node's IDs dont correspond to their
// hashes.
func fillBucket(tab *Table, ld int) (last *Node) {
b := tab.buckets[ld]
for len(b.entries) < bucketSize {
b.entries = append(b.entries, nodeAtDistance(tab.self.sha, ld))
}
return b.entries[bucketSize-1]
}
// nodeAtDistance creates a node for which logdist(base, n.sha) == ld.
// The node's ID does not correspond to n.sha.
func nodeAtDistance(base common.Hash, ld int) (n *Node) {
n = new(Node)
n.sha = hashAtDistance(base, ld)
copy(n.ID[:], n.sha[:]) // ensure the node still has a unique ID
return n
}
type pingRecorder struct{ responding, pinged map[NodeID]bool }
func newPingRecorder() *pingRecorder {
return &pingRecorder{make(map[NodeID]bool), make(map[NodeID]bool)}
}
func (t *pingRecorder) findnode(toid NodeID, toaddr *net.UDPAddr, target NodeID) ([]*Node, error) {
panic("findnode called on pingRecorder")
}
func (t *pingRecorder) close() {}
func (t *pingRecorder) waitping(from NodeID) error {
return nil // remote always pings
}
func (t *pingRecorder) ping(toid NodeID, toaddr *net.UDPAddr) error {
t.pinged[toid] = true
if t.responding[toid] {
return nil
} else {
return errTimeout
}
}
func TestTable_closest(t *testing.T) {
t.Parallel()
test := func(test *closeTest) bool {
// for any node table, Target and N
tab := newTable(test.Self, &net.UDPAddr{})
tab.stuff(test.All)
// check that doClosest(Target, N) returns nodes
result := tab.closest(test.Target, test.N).entries
if hasDuplicates(result) {
t.Errorf("result contains duplicates")
return false
}
if !sortedByDistanceTo(test.Target, result) {
t.Errorf("result is not sorted by distance to target")
return false
}
// check that the number of results is min(N, tablen)
wantN := test.N
if tab.count < test.N {
wantN = tab.count
}
if len(result) != wantN {
t.Errorf("wrong number of nodes: got %d, want %d", len(result), wantN)
return false
} else if len(result) == 0 {
return true // no need to check distance
}
// check that the result nodes have minimum distance to target.
for _, b := range tab.buckets {
for _, n := range b.entries {
if contains(result, n.ID) {
continue // don't run the check below for nodes in result
}
farthestResult := result[len(result)-1].sha
if distcmp(test.Target, n.sha, farthestResult) < 0 {
t.Errorf("table contains node that is closer to target but it's not in result")
t.Logf(" Target: %v", test.Target)
t.Logf(" Farthest Result: %v", farthestResult)
t.Logf(" ID: %v", n.ID)
return false
}
}
}
return true
}
if err := quick.Check(test, quickcfg()); err != nil {
t.Error(err)
}
}
func TestTable_ReadRandomNodesGetAll(t *testing.T) {
cfg := &quick.Config{
MaxCount: 200,
Rand: rand.New(rand.NewSource(time.Now().Unix())),
Values: func(args []reflect.Value, rand *rand.Rand) {
args[0] = reflect.ValueOf(make([]*Node, rand.Intn(1000)))
},
}
test := func(buf []*Node) bool {
tab := newTable(NodeID{}, &net.UDPAddr{})
for i := 0; i < len(buf); i++ {
ld := cfg.Rand.Intn(len(tab.buckets))
tab.stuff([]*Node{nodeAtDistance(tab.self.sha, ld)})
}
gotN := tab.readRandomNodes(buf)
if gotN != tab.count {
t.Errorf("wrong number of nodes, got %d, want %d", gotN, tab.count)
return false
}
if hasDuplicates(buf[:gotN]) {
t.Errorf("result contains duplicates")
return false
}
return true
}
if err := quick.Check(test, cfg); err != nil {
t.Error(err)
}
}
type closeTest struct {
Self NodeID
Target common.Hash
All []*Node
N int
}
func (*closeTest) Generate(rand *rand.Rand, size int) reflect.Value {
t := &closeTest{
Self: gen(NodeID{}, rand).(NodeID),
Target: gen(common.Hash{}, rand).(common.Hash),
N: rand.Intn(bucketSize),
}
for _, id := range gen([]NodeID{}, rand).([]NodeID) {
t.All = append(t.All, &Node{ID: id})
}
return reflect.ValueOf(t)
}
func hasDuplicates(slice []*Node) bool {
seen := make(map[NodeID]bool)
for i, e := range slice {
if e == nil {
panic(fmt.Sprintf("nil *Node at %d", i))
}
if seen[e.ID] {
return true
}
seen[e.ID] = true
}
return false
}
func sortedByDistanceTo(distbase common.Hash, slice []*Node) bool {
var last common.Hash
for i, e := range slice {
if i > 0 && distcmp(distbase, e.sha, last) < 0 {
return false
}
last = e.sha
}
return true
}
func contains(ns []*Node, id NodeID) bool {
for _, n := range ns {
if n.ID == id {
return true
}
}
return false
}
// gen wraps quick.Value so it's easier to use.
// it generates a random value of the given value's type.
func gen(typ interface{}, rand *rand.Rand) interface{} {
v, ok := quick.Value(reflect.TypeOf(typ), rand)
if !ok {
panic(fmt.Sprintf("couldn't generate random value of type %T", typ))
}
return v.Interface()
}
func newkey() *ecdsa.PrivateKey {
key, err := crypto.GenerateKey()
if err != nil {
panic("couldn't generate key: " + err.Error())
}
return key
}