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197a4f1ae8
tailscale/util/deephash/deephash_test.go
Brad Fitzpatrick 197a4f1ae8 types/ptr: move all the ptrTo funcs to one new package's ptr.To 
Change-Id: Ia0b820ffe7aa72897515f19bd415204b6fe743c7
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
2022-11-30 17:50:51 -08:00

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// Copyright (c) 2020 Tailscale Inc & AUTHORS All rights reserved.
// Use of this source code is governed by a BSD-style
// license that can be found in the LICENSE file.
package deephash
import (
"archive/tar"
"crypto/sha256"
"encoding/binary"
"fmt"
"hash"
"math"
"math/bits"
"math/rand"
"net/netip"
"reflect"
"runtime"
"testing"
"testing/quick"
"time"
qt "github.com/frankban/quicktest"
"go4.org/mem"
"go4.org/netipx"
"tailscale.com/tailcfg"
"tailscale.com/types/dnstype"
"tailscale.com/types/ipproto"
"tailscale.com/types/key"
"tailscale.com/types/ptr"
"tailscale.com/util/deephash/testtype"
"tailscale.com/util/dnsname"
"tailscale.com/version"
"tailscale.com/wgengine/filter"
"tailscale.com/wgengine/router"
"tailscale.com/wgengine/wgcfg"
)
type appendBytes []byte
func (p appendBytes) AppendTo(b []byte) []byte {
return append(b, p...)
}
func TestHash(t *testing.T) {
type tuple [2]any
type iface struct{ X any }
type scalars struct {
I8 int8
I16 int16
I32 int32
I64 int64
I int
U8 uint8
U16 uint16
U32 uint32
U64 uint64
U uint
UP uintptr
F32 float32
F64 float64
C64 complex64
C128 complex128
}
type MyBool bool
type MyHeader tar.Header
var zeroFloat64 float64
tests := []struct {
in tuple
wantEq bool
}{
{in: tuple{false, true}, wantEq: false},
{in: tuple{true, true}, wantEq: true},
{in: tuple{false, false}, wantEq: true},
{
in: tuple{
scalars{-8, -16, -32, -64, -1234, 8, 16, 32, 64, 1234, 5678, 32.32, 64.64, 32 + 32i, 64 + 64i},
scalars{-8, -16, -32, -64, -1234, 8, 16, 32, 64, 1234, 5678, 32.32, 64.64, 32 + 32i, 64 + 64i},
},
wantEq: true,
},
{in: tuple{scalars{I8: math.MinInt8}, scalars{I8: math.MinInt8 / 2}}, wantEq: false},
{in: tuple{scalars{I16: math.MinInt16}, scalars{I16: math.MinInt16 / 2}}, wantEq: false},
{in: tuple{scalars{I32: math.MinInt32}, scalars{I32: math.MinInt32 / 2}}, wantEq: false},
{in: tuple{scalars{I64: math.MinInt64}, scalars{I64: math.MinInt64 / 2}}, wantEq: false},
{in: tuple{scalars{I: -1234}, scalars{I: -1234 / 2}}, wantEq: false},
{in: tuple{scalars{U8: math.MaxUint8}, scalars{U8: math.MaxUint8 / 2}}, wantEq: false},
{in: tuple{scalars{U16: math.MaxUint16}, scalars{U16: math.MaxUint16 / 2}}, wantEq: false},
{in: tuple{scalars{U32: math.MaxUint32}, scalars{U32: math.MaxUint32 / 2}}, wantEq: false},
{in: tuple{scalars{U64: math.MaxUint64}, scalars{U64: math.MaxUint64 / 2}}, wantEq: false},
{in: tuple{scalars{U: 1234}, scalars{U: 1234 / 2}}, wantEq: false},
{in: tuple{scalars{UP: 5678}, scalars{UP: 5678 / 2}}, wantEq: false},
{in: tuple{scalars{F32: 32.32}, scalars{F32: math.Nextafter32(32.32, 0)}}, wantEq: false},
{in: tuple{scalars{F64: 64.64}, scalars{F64: math.Nextafter(64.64, 0)}}, wantEq: false},
{in: tuple{scalars{F32: float32(math.NaN())}, scalars{F32: float32(math.NaN())}}, wantEq: true},
{in: tuple{scalars{F64: float64(math.NaN())}, scalars{F64: float64(math.NaN())}}, wantEq: true},
{in: tuple{scalars{C64: 32 + 32i}, scalars{C64: complex(math.Nextafter32(32, 0), 32)}}, wantEq: false},
{in: tuple{scalars{C128: 64 + 64i}, scalars{C128: complex(math.Nextafter(64, 0), 64)}}, wantEq: false},
{in: tuple{[]int(nil), []int(nil)}, wantEq: true},
{in: tuple{[]int{}, []int(nil)}, wantEq: false},
{in: tuple{[]int{}, []int{}}, wantEq: true},
{in: tuple{[]string(nil), []string(nil)}, wantEq: true},
{in: tuple{[]string{}, []string(nil)}, wantEq: false},
{in: tuple{[]string{}, []string{}}, wantEq: true},
{in: tuple{[]appendBytes{{}, {0, 0, 0, 0, 0, 0, 0, 1}}, []appendBytes{{}, {0, 0, 0, 0, 0, 0, 0, 1}}}, wantEq: true},
{in: tuple{[]appendBytes{{}, {0, 0, 0, 0, 0, 0, 0, 1}}, []appendBytes{{0, 0, 0, 0, 0, 0, 0, 1}, {}}}, wantEq: false},
{in: tuple{iface{MyBool(true)}, iface{MyBool(true)}}, wantEq: true},
{in: tuple{iface{true}, iface{MyBool(true)}}, wantEq: false},
{in: tuple{iface{MyHeader{}}, iface{MyHeader{}}}, wantEq: true},
{in: tuple{iface{MyHeader{}}, iface{tar.Header{}}}, wantEq: false},
{in: tuple{iface{&MyHeader{}}, iface{&MyHeader{}}}, wantEq: true},
{in: tuple{iface{&MyHeader{}}, iface{&tar.Header{}}}, wantEq: false},
{in: tuple{iface{[]map[string]MyBool{}}, iface{[]map[string]MyBool{}}}, wantEq: true},
{in: tuple{iface{[]map[string]bool{}}, iface{[]map[string]MyBool{}}}, wantEq: false},
{in: tuple{zeroFloat64, -zeroFloat64}, wantEq: false}, // Issue 4883 (false alarm)
{in: tuple{[]any(nil), 0.0}, wantEq: false}, // Issue 4883
{in: tuple{[]any(nil), uint8(0)}, wantEq: false}, // Issue 4883
{in: tuple{nil, nil}, wantEq: true}, // Issue 4883
{
in: func() tuple {
i1 := 1
i2 := 2
v1 := [3]*int{&i1, &i2, &i1}
v2 := [3]*int{&i1, &i2, &i2}
return tuple{v1, v2}
}(),
wantEq: false,
},
{in: tuple{netip.Addr{}, netip.Addr{}}, wantEq: true},
{in: tuple{netip.Addr{}, netip.AddrFrom4([4]byte{})}, wantEq: false},
{in: tuple{netip.AddrFrom4([4]byte{}), netip.AddrFrom4([4]byte{})}, wantEq: true},
{in: tuple{netip.AddrFrom4([4]byte{192, 168, 0, 1}), netip.AddrFrom4([4]byte{192, 168, 0, 1})}, wantEq: true},
{in: tuple{netip.AddrFrom4([4]byte{192, 168, 0, 1}), netip.AddrFrom4([4]byte{192, 168, 0, 2})}, wantEq: false},
{in: tuple{netip.AddrFrom4([4]byte{}), netip.AddrFrom16([16]byte{})}, wantEq: false},
{in: tuple{netip.AddrFrom16([16]byte{}), netip.AddrFrom16([16]byte{})}, wantEq: true},
{in: tuple{netip.AddrPort{}, netip.AddrPort{}}, wantEq: true},
{in: tuple{netip.AddrPort{}, netip.AddrPortFrom(netip.AddrFrom4([4]byte{}), 0)}, wantEq: false},
{in: tuple{netip.AddrPortFrom(netip.AddrFrom4([4]byte{}), 0), netip.AddrPortFrom(netip.AddrFrom4([4]byte{}), 0)}, wantEq: true},
{in: tuple{netip.AddrPortFrom(netip.AddrFrom4([4]byte{192, 168, 0, 1}), 1234), netip.AddrPortFrom(netip.AddrFrom4([4]byte{192, 168, 0, 1}), 1234)}, wantEq: true},
{in: tuple{netip.AddrPortFrom(netip.AddrFrom4([4]byte{192, 168, 0, 1}), 1234), netip.AddrPortFrom(netip.AddrFrom4([4]byte{192, 168, 0, 1}), 1235)}, wantEq: false},
{in: tuple{netip.AddrPortFrom(netip.AddrFrom4([4]byte{192, 168, 0, 1}), 1234), netip.AddrPortFrom(netip.AddrFrom4([4]byte{192, 168, 0, 2}), 1234)}, wantEq: false},
{in: tuple{netip.Prefix{}, netip.Prefix{}}, wantEq: true},
{in: tuple{netip.Prefix{}, netip.PrefixFrom(netip.Addr{}, 1)}, wantEq: false},
{in: tuple{netip.Prefix{}, netip.PrefixFrom(netip.AddrFrom4([4]byte{}), 0)}, wantEq: false},
{in: tuple{netip.PrefixFrom(netip.AddrFrom4([4]byte{}), 1), netip.PrefixFrom(netip.AddrFrom4([4]byte{}), 1)}, wantEq: true},
{in: tuple{netip.PrefixFrom(netip.AddrFrom4([4]byte{192, 168, 0, 1}), 1), netip.PrefixFrom(netip.AddrFrom4([4]byte{192, 168, 0, 1}), 1)}, wantEq: true},
{in: tuple{netip.PrefixFrom(netip.AddrFrom4([4]byte{192, 168, 0, 1}), 1), netip.PrefixFrom(netip.AddrFrom4([4]byte{192, 168, 0, 1}), 0)}, wantEq: false},
{in: tuple{netip.PrefixFrom(netip.AddrFrom4([4]byte{192, 168, 0, 1}), 1), netip.PrefixFrom(netip.AddrFrom4([4]byte{192, 168, 0, 2}), 1)}, wantEq: false},
{in: tuple{netipx.IPRange{}, netipx.IPRange{}}, wantEq: true},
{in: tuple{netipx.IPRange{}, netipx.IPRangeFrom(netip.AddrFrom4([4]byte{}), netip.AddrFrom16([16]byte{}))}, wantEq: false},
{in: tuple{netipx.IPRangeFrom(netip.AddrFrom4([4]byte{}), netip.AddrFrom16([16]byte{})), netipx.IPRangeFrom(netip.AddrFrom4([4]byte{}), netip.AddrFrom16([16]byte{}))}, wantEq: true},
{in: tuple{netipx.IPRangeFrom(netip.AddrFrom4([4]byte{192, 168, 0, 1}), netip.AddrFrom4([4]byte{192, 168, 0, 100})), netipx.IPRangeFrom(netip.AddrFrom4([4]byte{192, 168, 0, 1}), netip.AddrFrom4([4]byte{192, 168, 0, 100}))}, wantEq: true},
{in: tuple{netipx.IPRangeFrom(netip.AddrFrom4([4]byte{192, 168, 0, 1}), netip.AddrFrom4([4]byte{192, 168, 0, 100})), netipx.IPRangeFrom(netip.AddrFrom4([4]byte{192, 168, 0, 1}), netip.AddrFrom4([4]byte{192, 168, 0, 101}))}, wantEq: false},
{in: tuple{netipx.IPRangeFrom(netip.AddrFrom4([4]byte{192, 168, 0, 1}), netip.AddrFrom4([4]byte{192, 168, 0, 100})), netipx.IPRangeFrom(netip.AddrFrom4([4]byte{192, 168, 0, 2}), netip.AddrFrom4([4]byte{192, 168, 0, 100}))}, wantEq: false},
{in: tuple{key.DiscoPublic{}, key.DiscoPublic{}}, wantEq: true},
{in: tuple{key.DiscoPublic{}, key.DiscoPublicFromRaw32(mem.B(func() []byte {
b := make([]byte, 32)
b[0] = 1
return b
}()))}, wantEq: false},
{in: tuple{key.NodePublic{}, key.NodePublic{}}, wantEq: true},
{in: tuple{key.NodePublic{}, key.NodePublicFromRaw32(mem.B(func() []byte {
b := make([]byte, 32)
b[0] = 1
return b
}()))}, wantEq: false},
}
for _, tt := range tests {
gotEq := Hash(&tt.in[0]) == Hash(&tt.in[1])
if gotEq != tt.wantEq {
t.Errorf("(Hash(%T %v) == Hash(%T %v)) = %v, want %v", tt.in[0], tt.in[0], tt.in[1], tt.in[1], gotEq, tt.wantEq)
}
}
}
func TestDeepHash(t *testing.T) {
// v contains the types of values we care about for our current callers.
// Mostly we're just testing that we don't panic on handled types.
v := getVal()
hash1 := Hash(v)
t.Logf("hash: %v", hash1)
for i := 0; i < 20; i++ {
v := getVal()
hash2 := Hash(v)
if hash1 != hash2 {
t.Error("second hash didn't match")
}
}
}
// Tests that we actually hash map elements. Whoops.
func TestIssue4868(t *testing.T) {
m1 := map[int]string{1: "foo"}
m2 := map[int]string{1: "bar"}
if Hash(&m1) == Hash(&m2) {
t.Error("bogus")
}
}
func TestIssue4871(t *testing.T) {
m1 := map[string]string{"": "", "x": "foo"}
m2 := map[string]string{}
if h1, h2 := Hash(&m1), Hash(&m2); h1 == h2 {
t.Errorf("bogus: h1=%x, h2=%x", h1, h2)
}
}
func TestNilVsEmptymap(t *testing.T) {
m1 := map[string]string(nil)
m2 := map[string]string{}
if h1, h2 := Hash(&m1), Hash(&m2); h1 == h2 {
t.Errorf("bogus: h1=%x, h2=%x", h1, h2)
}
}
func TestMapFraming(t *testing.T) {
m1 := map[string]string{"foo": "", "fo": "o"}
m2 := map[string]string{}
if h1, h2 := Hash(&m1), Hash(&m2); h1 == h2 {
t.Errorf("bogus: h1=%x, h2=%x", h1, h2)
}
}
func TestQuick(t *testing.T) {
initSeed()
err := quick.Check(func(v, w map[string]string) bool {
return (Hash(&v) == Hash(&w)) == reflect.DeepEqual(v, w)
}, &quick.Config{MaxCount: 1000, Rand: rand.New(rand.NewSource(int64(seed)))})
if err != nil {
t.Fatalf("seed=%v, err=%v", seed, err)
}
}
type tailscaleTypes struct {
WGConfig *wgcfg.Config
RouterConfig *router.Config
MapFQDNAddrs map[dnsname.FQDN][]netip.Addr
MapFQDNAddrPorts map[dnsname.FQDN][]netip.AddrPort
MapDiscoPublics map[key.DiscoPublic]bool
MapResponse *tailcfg.MapResponse
FilterMatch filter.Match
}
func getVal() *tailscaleTypes {
return &tailscaleTypes{
&wgcfg.Config{
Name: "foo",
Addresses: []netip.Prefix{netip.PrefixFrom(netip.AddrFrom16([16]byte{3: 3}).Unmap(), 5)},
Peers: []wgcfg.Peer{
{
PublicKey: key.NodePublic{},
},
},
},
&router.Config{
Routes: []netip.Prefix{
netip.MustParsePrefix("1.2.3.0/24"),
netip.MustParsePrefix("1234::/64"),
},
},
map[dnsname.FQDN][]netip.Addr{
dnsname.FQDN("a."): {netip.MustParseAddr("1.2.3.4"), netip.MustParseAddr("4.3.2.1")},
dnsname.FQDN("b."): {netip.MustParseAddr("8.8.8.8"), netip.MustParseAddr("9.9.9.9")},
dnsname.FQDN("c."): {netip.MustParseAddr("6.6.6.6"), netip.MustParseAddr("7.7.7.7")},
dnsname.FQDN("d."): {netip.MustParseAddr("6.7.6.6"), netip.MustParseAddr("7.7.7.8")},
dnsname.FQDN("e."): {netip.MustParseAddr("6.8.6.6"), netip.MustParseAddr("7.7.7.9")},
dnsname.FQDN("f."): {netip.MustParseAddr("6.9.6.6"), netip.MustParseAddr("7.7.7.0")},
},
map[dnsname.FQDN][]netip.AddrPort{
dnsname.FQDN("a."): {netip.MustParseAddrPort("1.2.3.4:11"), netip.MustParseAddrPort("4.3.2.1:22")},
dnsname.FQDN("b."): {netip.MustParseAddrPort("8.8.8.8:11"), netip.MustParseAddrPort("9.9.9.9:22")},
dnsname.FQDN("c."): {netip.MustParseAddrPort("8.8.8.8:12"), netip.MustParseAddrPort("9.9.9.9:23")},
dnsname.FQDN("d."): {netip.MustParseAddrPort("8.8.8.8:13"), netip.MustParseAddrPort("9.9.9.9:24")},
dnsname.FQDN("e."): {netip.MustParseAddrPort("8.8.8.8:14"), netip.MustParseAddrPort("9.9.9.9:25")},
},
map[key.DiscoPublic]bool{
key.DiscoPublicFromRaw32(mem.B([]byte{1: 1, 31: 0})): true,
key.DiscoPublicFromRaw32(mem.B([]byte{1: 2, 31: 0})): false,
key.DiscoPublicFromRaw32(mem.B([]byte{1: 3, 31: 0})): true,
key.DiscoPublicFromRaw32(mem.B([]byte{1: 4, 31: 0})): false,
},
&tailcfg.MapResponse{
DERPMap: &tailcfg.DERPMap{
Regions: map[int]*tailcfg.DERPRegion{
1: {
RegionID: 1,
RegionCode: "foo",
Nodes: []*tailcfg.DERPNode{
{
Name: "n1",
RegionID: 1,
HostName: "foo.com",
},
{
Name: "n2",
RegionID: 1,
HostName: "bar.com",
},
},
},
},
},
DNSConfig: &tailcfg.DNSConfig{
Resolvers: []*dnstype.Resolver{
{Addr: "10.0.0.1"},
},
},
PacketFilter: []tailcfg.FilterRule{
{
SrcIPs: []string{"1.2.3.4"},
DstPorts: []tailcfg.NetPortRange{
{
IP: "1.2.3.4/32",
Ports: tailcfg.PortRange{First: 1, Last: 2},
},
},
},
},
Peers: []*tailcfg.Node{
{
ID: 1,
},
{
ID: 2,
},
},
UserProfiles: []tailcfg.UserProfile{
{ID: 1, LoginName: "foo@bar.com"},
{ID: 2, LoginName: "bar@foo.com"},
},
},
filter.Match{
IPProto: []ipproto.Proto{1, 2, 3},
},
}
}
type IntThenByte struct {
i int
b byte
}
type TwoInts struct{ a, b int }
type IntIntByteInt struct {
i1, i2 int32
b byte // padding after
i3 int32
}
func u8(n uint8) string { return string([]byte{n}) }
func u16(n uint16) string { return string(binary.LittleEndian.AppendUint16(nil, n)) }
func u32(n uint32) string { return string(binary.LittleEndian.AppendUint32(nil, n)) }
func u64(n uint64) string { return string(binary.LittleEndian.AppendUint64(nil, n)) }
func ux(n uint) string {
if bits.UintSize == 32 {
return u32(uint32(n))
} else {
return u64(uint64(n))
}
}
func TestGetTypeHasher(t *testing.T) {
switch runtime.GOARCH {
case "amd64", "arm64", "arm", "386", "riscv64":
default:
// Test outputs below are specifically for little-endian machines.
// Just skip everything else for now. Feel free to add more above if
// you have the hardware to test and it's little-endian.
t.Skipf("skipping on %v", runtime.GOARCH)
}
type typedString string
var (
someInt = int('A')
someComplex128 = complex128(1 + 2i)
someIP = netip.MustParseAddr("1.2.3.4")
)
tests := []struct {
name string
val any
out string
out32 string // overwrites out if 32-bit
}{
{
name: "int",
val: int(1),
out: ux(1),
},
{
name: "int_negative",
val: int(-1),
out: ux(math.MaxUint),
},
{
name: "int8",
val: int8(1),
out: "\x01",
},
{
name: "float64",
val: float64(1.0),
out: "\x00\x00\x00\x00\x00\x00\xf0?",
},
{
name: "float32",
val: float32(1.0),
out: "\x00\x00\x80?",
},
{
name: "string",
val: "foo",
out: "\x03\x00\x00\x00\x00\x00\x00\x00foo",
},
{
name: "typedString",
val: typedString("foo"),
out: "\x03\x00\x00\x00\x00\x00\x00\x00foo",
},
{
name: "string_slice",
val: []string{"foo", "bar"},
out: "\x01\x02\x00\x00\x00\x00\x00\x00\x00\x03\x00\x00\x00\x00\x00\x00\x00foo\x03\x00\x00\x00\x00\x00\x00\x00bar",
},
{
name: "int_slice",
val: []int{1, 0, -1},
out: "\x01\x03\x00\x00\x00\x00\x00\x00\x00\x01\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\xff\xff\xff\xff\xff\xff\xff\xff",
out32: "\x01\x03\x00\x00\x00\x00\x00\x00\x00\x01\x00\x00\x00\x00\x00\x00\x00\xff\xff\xff\xff",
},
{
name: "struct",
val: struct {
a, b int
c uint16
}{1, -1, 2},
out: "\x01\x00\x00\x00\x00\x00\x00\x00\xff\xff\xff\xff\xff\xff\xff\xff\x02\x00",
out32: "\x01\x00\x00\x00\xff\xff\xff\xff\x02\x00",
},
{
name: "nil_int_ptr",
val: (*int)(nil),
out: "\x00",
},
{
name: "int_ptr",
val: &someInt,
out: "\x01A\x00\x00\x00\x00\x00\x00\x00",
out32: "\x01A\x00\x00\x00",
},
{
name: "nil_uint32_ptr",
val: (*uint32)(nil),
out: "\x00",
},
{
name: "complex128_ptr",
val: &someComplex128,
out: "\x01\x00\x00\x00\x00\x00\x00\xf0?\x00\x00\x00\x00\x00\x00\x00@",
},
{
name: "packet_filter",
val: filterRules,
out: "\x01\x04\x00\x00\x00\x00\x00\x00\x00\x01\x03\x00\x00\x00\x00\x00\x00\x00\x01\x00\x00\x00\x00\x00\x00\x00*\v\x00\x00\x00\x00\x00\x00\x0010.1.3.4/32\v\x00\x00\x00\x00\x00\x00\x0010.0.0.0/24\x01\x03\x00\x00\x00\x00\x00\x00\x00\x01\x00\x00\x00\x00\x00\x00\x00\x02\x00\x00\x00\x00\x00\x00\x00\x03\x00\x00\x00\x00\x00\x00\x00\x01\x01\x00\x00\x00\x00\x00\x00\x00\n\x00\x00\x00\x00\x00\x00\x001.2.3.4/32\x01 \x00\x00\x00\x00\x00\x00\x00\x01\x00\x02\x00\x01\x04\x00\x00\x00\x00\x00\x00\x00\x01\x00\x00\x00\x00\x00\x00\x00\x02\x00\x00\x00\x00\x00\x00\x00\x03\x00\x00\x00\x00\x00\x00\x00\x04\x00\x00\x00\x00\x00\x00\x00\x01\x01\x00\x00\x00\x00\x00\x00\x00\x01\x01\x00\x00\x00\x00\x00\x00\x00\x04\x00\x00\x00\x00\x00\x00\x00\x01\x02\x03\x04 \x00\x01\x01\x00\x00\x00\x00\x00\x00\x00\x03\x00\x00\x00\x00\x00\x00\x00foo\x01\x01\x00\x00\x00\x00\x00\x00\x00\v\x00\x00\x00\x00\x00\x00\x00foooooooooo\x00\x01\x01\x00\x00\x00\x00\x00\x00\x00\f\x00\x00\x00\x00\x00\x00\x00baaaaaarrrrr\x00\x01\x00\x02\x00\x00\x00\x01\x01\x00\x00\x00\x00\x00\x00\x00\v\x00\x00\x00\x00\x00\x00\x00foooooooooo\x00\x01\x01\x00\x00\x00\x00\x00\x00\x00\f\x00\x00\x00\x00\x00\x00\x00baaaaaarrrrr\x00\x01\x00\x02\x00\x00\x00\x01\x01\x00\x00\x00\x00\x00\x00\x00\v\x00\x00\x00\x00\x00\x00\x00foooooooooo\x00\x01\x01\x00\x00\x00\x00\x00\x00\x00\f\x00\x00\x00\x00\x00\x00\x00baaaaaarrrrr\x00\x01\x00\x02\x00\x00\x00",
out32: "\x01\x04\x00\x00\x00\x00\x00\x00\x00\x01\x03\x00\x00\x00\x00\x00\x00\x00\x01\x00\x00\x00\x00\x00\x00\x00*\v\x00\x00\x00\x00\x00\x00\x0010.1.3.4/32\v\x00\x00\x00\x00\x00\x00\x0010.0.0.0/24\x01\x03\x00\x00\x00\x00\x00\x00\x00\x01\x00\x00\x00\x02\x00\x00\x00\x03\x00\x00\x00\x01\x01\x00\x00\x00\x00\x00\x00\x00\n\x00\x00\x00\x00\x00\x00\x001.2.3.4/32\x01 \x00\x00\x00\x01\x00\x02\x00\x01\x04\x00\x00\x00\x00\x00\x00\x00\x01\x00\x00\x00\x02\x00\x00\x00\x03\x00\x00\x00\x04\x00\x00\x00\x01\x01\x00\x00\x00\x00\x00\x00\x00\x01\x01\x00\x00\x00\x00\x00\x00\x00\x04\x00\x00\x00\x00\x00\x00\x00\x01\x02\x03\x04 \x00\x01\x01\x00\x00\x00\x00\x00\x00\x00\x03\x00\x00\x00\x00\x00\x00\x00foo\x01\x01\x00\x00\x00\x00\x00\x00\x00\v\x00\x00\x00\x00\x00\x00\x00foooooooooo\x00\x01\x01\x00\x00\x00\x00\x00\x00\x00\f\x00\x00\x00\x00\x00\x00\x00baaaaaarrrrr\x00\x01\x00\x02\x00\x00\x00\x01\x01\x00\x00\x00\x00\x00\x00\x00\v\x00\x00\x00\x00\x00\x00\x00foooooooooo\x00\x01\x01\x00\x00\x00\x00\x00\x00\x00\f\x00\x00\x00\x00\x00\x00\x00baaaaaarrrrr\x00\x01\x00\x02\x00\x00\x00\x01\x01\x00\x00\x00\x00\x00\x00\x00\v\x00\x00\x00\x00\x00\x00\x00foooooooooo\x00\x01\x01\x00\x00\x00\x00\x00\x00\x00\f\x00\x00\x00\x00\x00\x00\x00baaaaaarrrrr\x00\x01\x00\x02\x00\x00\x00",
},
{
name: "netip.Addr",
val: netip.MustParseAddr("fe80::123%foo"),
out: u64(16+3) + u64(0x80fe) + u64(0x2301<<48) + "foo",
},
{
name: "ptr-netip.Addr",
val: &someIP,
out: u8(1) + u64(4) + u32(0x04030201),
},
{
name: "ptr-nil-netip.Addr",
val: (*netip.Addr)(nil),
out: "\x00",
},
{
name: "time",
val: time.Unix(1234, 5678).In(time.UTC),
out: u64(1234) + u32(5678) + u32(0),
},
{
name: "time_ptr", // addressable, as opposed to "time" test above
val: ptr.To(time.Unix(1234, 5678).In(time.UTC)),
out: u8(1) + u64(1234) + u32(5678) + u32(0),
},
{
name: "time_ptr_via_unexported",
val: testtype.NewUnexportedAddressableTime(time.Unix(1234, 5678).In(time.UTC)),
out: u8(1) + u64(1234) + u32(5678) + u32(0),
},
{
name: "time_ptr_via_unexported_value",
val: *testtype.NewUnexportedAddressableTime(time.Unix(1234, 5678).In(time.UTC)),
out: u64(1234) + u32(5678) + u32(0),
},
{
name: "time_custom_zone",
val: time.Unix(1655311822, 0).In(time.FixedZone("FOO", -60*60)),
out: u64(1655311822) + u32(0) + u32(math.MaxUint32-60*60+1),
},
{
name: "time_nil",
val: (*time.Time)(nil),
out: "\x00",
},
{
name: "array_memhash",
val: [4]byte{1, 2, 3, 4},
out: "\x01\x02\x03\x04",
},
{
name: "array_ptr_memhash",
val: ptr.To([4]byte{1, 2, 3, 4}),
out: "\x01\x01\x02\x03\x04",
},
{
name: "ptr_to_struct_partially_memhashable",
val: &struct {
A int16
B int16
C *int
}{5, 6, nil},
out: "\x01\x05\x00\x06\x00\x00",
},
{
name: "struct_partially_memhashable_but_cant_addr",
val: struct {
A int16
B int16
C *int
}{5, 6, nil},
out: "\x05\x00\x06\x00\x00",
},
{
name: "array_elements",
val: [4]byte{1, 2, 3, 4},
out: "\x01\x02\x03\x04",
},
{
name: "bool",
val: true,
out: "\x01",
},
{
name: "IntIntByteInt",
val: IntIntByteInt{1, 2, 3, 4},
out: "\x01\x00\x00\x00\x02\x00\x00\x00\x03\x04\x00\x00\x00",
},
{
name: "IntIntByteInt-canaddr",
val: &IntIntByteInt{1, 2, 3, 4},
out: "\x01\x01\x00\x00\x00\x02\x00\x00\x00\x03\x04\x00\x00\x00",
},
{
name: "array-IntIntByteInt",
val: [2]IntIntByteInt{
{1, 2, 3, 4},
{5, 6, 7, 8},
},
out: "\x01\x00\x00\x00\x02\x00\x00\x00\x03\x04\x00\x00\x00\x05\x00\x00\x00\x06\x00\x00\x00\a\b\x00\x00\x00",
},
{
name: "array-IntIntByteInt-canaddr",
val: &[2]IntIntByteInt{
{1, 2, 3, 4},
{5, 6, 7, 8},
},
out: "\x01\x01\x00\x00\x00\x02\x00\x00\x00\x03\x04\x00\x00\x00\x05\x00\x00\x00\x06\x00\x00\x00\a\b\x00\x00\x00",
},
{
name: "tailcfg.Node",
val: &tailcfg.Node{},
out: "\x01\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\tn\x88\xf1\xff\xff\xff\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\tn\x88\xf1\xff\xff\xff\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00",
},
}
for _, tt := range tests {
t.Run(tt.name, func(t *testing.T) {
rv := reflect.ValueOf(tt.val)
va := reflect.New(rv.Type()).Elem()
va.Set(rv)
fn := lookupTypeHasher(va.Type())
hb := &hashBuffer{Hash: sha256.New()}
h := new(hasher)
h.Block512.Hash = hb
fn(h, pointerOf(va.Addr()))
const ptrSize = 32 << uintptr(^uintptr(0)>>63)
if tt.out32 != "" && ptrSize == 32 {
tt.out = tt.out32
}
h.sum()
if got := string(hb.B); got != tt.out {
t.Fatalf("got %q; want %q", got, tt.out)
}
})
}
}
func TestSliceCycle(t *testing.T) {
type S []S
c := qt.New(t)
a := make(S, 1) // cyclic graph of 1 node
a[0] = a
b := make(S, 1) // cyclic graph of 1 node
b[0] = b
ha := Hash(&a)
hb := Hash(&b)
c.Assert(ha, qt.Equals, hb)
c1 := make(S, 1) // cyclic graph of 2 nodes
c2 := make(S, 1) // cyclic graph of 2 nodes
c1[0] = c2
c2[0] = c1
hc1 := Hash(&c1)
hc2 := Hash(&c2)
c.Assert(hc1, qt.Equals, hc2)
c.Assert(ha, qt.Not(qt.Equals), hc1)
c.Assert(hb, qt.Not(qt.Equals), hc2)
c3 := make(S, 1) // graph of 1 node pointing to cyclic graph of 2 nodes
c3[0] = c1
hc3 := Hash(&c3)
c.Assert(hc1, qt.Not(qt.Equals), hc3)
c4 := make(S, 2) // cyclic graph of 3 nodes
c5 := make(S, 2) // cyclic graph of 3 nodes
c4[0] = nil
c4[1] = c4
c5[0] = c5
c5[1] = nil
hc4 := Hash(&c4)
hc5 := Hash(&c5)
c.Assert(hc4, qt.Not(qt.Equals), hc5) // cycle occurs through different indexes
}
func TestMapCycle(t *testing.T) {
type M map[string]M
c := qt.New(t)
a := make(M) // cyclic graph of 1 node
a["self"] = a
b := make(M) // cyclic graph of 1 node
b["self"] = b
ha := Hash(&a)
hb := Hash(&b)
c.Assert(ha, qt.Equals, hb)
c1 := make(M) // cyclic graph of 2 nodes
c2 := make(M) // cyclic graph of 2 nodes
c1["peer"] = c2
c2["peer"] = c1
hc1 := Hash(&c1)
hc2 := Hash(&c2)
c.Assert(hc1, qt.Equals, hc2)
c.Assert(ha, qt.Not(qt.Equals), hc1)
c.Assert(hb, qt.Not(qt.Equals), hc2)
c3 := make(M) // graph of 1 node pointing to cyclic graph of 2 nodes
c3["child"] = c1
hc3 := Hash(&c3)
c.Assert(hc1, qt.Not(qt.Equals), hc3)
c4 := make(M) // cyclic graph of 3 nodes
c5 := make(M) // cyclic graph of 3 nodes
c4["0"] = nil
c4["1"] = c4
c5["0"] = c5
c5["1"] = nil
hc4 := Hash(&c4)
hc5 := Hash(&c5)
c.Assert(hc4, qt.Not(qt.Equals), hc5) // cycle occurs through different keys
}
func TestPointerCycle(t *testing.T) {
type P *P
c := qt.New(t)
a := new(P) // cyclic graph of 1 node
*a = a
b := new(P) // cyclic graph of 1 node
*b = b
ha := Hash(&a)
hb := Hash(&b)
c.Assert(ha, qt.Equals, hb)
c1 := new(P) // cyclic graph of 2 nodes
c2 := new(P) // cyclic graph of 2 nodes
*c1 = c2
*c2 = c1
hc1 := Hash(&c1)
hc2 := Hash(&c2)
c.Assert(hc1, qt.Equals, hc2)
c.Assert(ha, qt.Not(qt.Equals), hc1)
c.Assert(hb, qt.Not(qt.Equals), hc2)
c3 := new(P) // graph of 1 node pointing to cyclic graph of 2 nodes
*c3 = c1
hc3 := Hash(&c3)
c.Assert(hc1, qt.Not(qt.Equals), hc3)
}
func TestInterfaceCycle(t *testing.T) {
type I struct{ v any }
c := qt.New(t)
a := new(I) // cyclic graph of 1 node
a.v = a
b := new(I) // cyclic graph of 1 node
b.v = b
ha := Hash(&a)
hb := Hash(&b)
c.Assert(ha, qt.Equals, hb)
c1 := new(I) // cyclic graph of 2 nodes
c2 := new(I) // cyclic graph of 2 nodes
c1.v = c2
c2.v = c1
hc1 := Hash(&c1)
hc2 := Hash(&c2)
c.Assert(hc1, qt.Equals, hc2)
c.Assert(ha, qt.Not(qt.Equals), hc1)
c.Assert(hb, qt.Not(qt.Equals), hc2)
c3 := new(I) // graph of 1 node pointing to cyclic graph of 2 nodes
c3.v = c1
hc3 := Hash(&c3)
c.Assert(hc1, qt.Not(qt.Equals), hc3)
}
var sink Sum
func BenchmarkHash(b *testing.B) {
b.ReportAllocs()
v := getVal()
for i := 0; i < b.N; i++ {
sink = Hash(v)
}
}
// filterRules is a packet filter that has both everything populated (in its
// first element) and also a few entries that are the typical shape for regular
// packet filters as sent to clients.
var filterRules = []tailcfg.FilterRule{
{
SrcIPs: []string{"*", "10.1.3.4/32", "10.0.0.0/24"},
SrcBits: []int{1, 2, 3},
DstPorts: []tailcfg.NetPortRange{{
IP: "1.2.3.4/32",
Bits: ptr.To(32),
Ports: tailcfg.PortRange{First: 1, Last: 2},
}},
IPProto: []int{1, 2, 3, 4},
CapGrant: []tailcfg.CapGrant{{
Dsts: []netip.Prefix{netip.MustParsePrefix("1.2.3.4/32")},
Caps: []string{"foo"},
}},
},
{
SrcIPs: []string{"foooooooooo"},
DstPorts: []tailcfg.NetPortRange{{
IP: "baaaaaarrrrr",
Ports: tailcfg.PortRange{First: 1, Last: 2},
}},
},
{
SrcIPs: []string{"foooooooooo"},
DstPorts: []tailcfg.NetPortRange{{
IP: "baaaaaarrrrr",
Ports: tailcfg.PortRange{First: 1, Last: 2},
}},
},
{
SrcIPs: []string{"foooooooooo"},
DstPorts: []tailcfg.NetPortRange{{
IP: "baaaaaarrrrr",
Ports: tailcfg.PortRange{First: 1, Last: 2},
}},
},
}
func BenchmarkHashPacketFilter(b *testing.B) {
b.ReportAllocs()
for i := 0; i < b.N; i++ {
sink = Hash(&filterRules)
}
}
func TestHashMapAcyclic(t *testing.T) {
m := map[int]string{}
for i := 0; i < 100; i++ {
m[i] = fmt.Sprint(i)
}
got := map[string]bool{}
hb := &hashBuffer{Hash: sha256.New()}
hash := lookupTypeHasher(reflect.TypeOf(m))
for i := 0; i < 20; i++ {
va := reflect.ValueOf(&m).Elem()
hb.Reset()
h := new(hasher)
h.Block512.Hash = hb
hash(h, pointerOf(va.Addr()))
h.sum()
if got[string(hb.B)] {
continue
}
got[string(hb.B)] = true
}
if len(got) != 1 {
t.Errorf("got %d results; want 1", len(got))
}
}
func TestPrintArray(t *testing.T) {
type T struct {
X [32]byte
}
x := T{X: [32]byte{1: 1, 31: 31}}
hb := &hashBuffer{Hash: sha256.New()}
h := new(hasher)
h.Block512.Hash = hb
va := reflect.ValueOf(&x).Elem()
hash := lookupTypeHasher(va.Type())
hash(h, pointerOf(va.Addr()))
h.sum()
const want = "\x00\x01\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x1f"
if got := hb.B; string(got) != want {
t.Errorf("wrong:\n got: %q\nwant: %q\n", got, want)
}
}
func BenchmarkHashMapAcyclic(b *testing.B) {
b.ReportAllocs()
m := map[int]string{}
for i := 0; i < 100; i++ {
m[i] = fmt.Sprint(i)
}
hb := &hashBuffer{Hash: sha256.New()}
va := reflect.ValueOf(&m).Elem()
hash := lookupTypeHasher(va.Type())
h := new(hasher)
h.Block512.Hash = hb
for i := 0; i < b.N; i++ {
h.Reset()
hash(h, pointerOf(va.Addr()))
}
}
func BenchmarkTailcfgNode(b *testing.B) {
b.ReportAllocs()
node := new(tailcfg.Node)
for i := 0; i < b.N; i++ {
sink = Hash(node)
}
}
func TestExhaustive(t *testing.T) {
seen := make(map[Sum]bool)
for i := 0; i < 100000; i++ {
s := Hash(&i)
if seen[s] {
t.Fatalf("hash collision %v", i)
}
seen[s] = true
}
}
// verify this doesn't loop forever, as it used to (Issue 2340)
func TestMapCyclicFallback(t *testing.T) {
type T struct {
M map[string]any
}
v := &T{
M: map[string]any{},
}
v.M["m"] = v.M
Hash(v)
}
func TestArrayAllocs(t *testing.T) {
if version.IsRace() {
t.Skip("skipping test under race detector")
}
// In theory, there should be no allocations. However, escape analysis on
// certain architectures fails to detect that certain cases do not escape.
// This discrepancy currently affects sha256.digest.Sum.
// Measure the number of allocations in sha256 to ensure that Hash does
// not allocate on top of its usage of sha256.
// See https://golang.org/issue/48055.
var b []byte
h := sha256.New()
want := int(testing.AllocsPerRun(1000, func() {
b = h.Sum(b[:0])
}))
switch runtime.GOARCH {
case "amd64", "arm64":
want = 0 // ensure no allocations on popular architectures
}
type T struct {
X [32]byte
}
x := &T{X: [32]byte{1: 1, 2: 2, 3: 3, 4: 4}}
got := int(testing.AllocsPerRun(1000, func() {
sink = Hash(x)
}))
if got > want {
t.Errorf("allocs = %v; want %v", got, want)
}
}
// Test for http://go/corp/6311 issue.
func TestHashThroughView(t *testing.T) {
type sshPolicyOut struct {
Rules []tailcfg.SSHRuleView
}
type mapResponseOut struct {
SSHPolicy *sshPolicyOut
}
// Just test we don't panic:
_ = Hash(&mapResponseOut{
SSHPolicy: &sshPolicyOut{
Rules: []tailcfg.SSHRuleView{
(&tailcfg.SSHRule{
RuleExpires: ptr.To(time.Unix(123, 0)),
}).View(),
},
},
})
}
func BenchmarkHashArray(b *testing.B) {
b.ReportAllocs()
type T struct {
X [32]byte
}
x := &T{X: [32]byte{1: 1, 2: 2, 3: 3, 4: 4}}
for i := 0; i < b.N; i++ {
sink = Hash(x)
}
}
// hashBuffer is a hash.Hash that buffers all written data.
type hashBuffer struct {
hash.Hash
B []byte
}
func (h *hashBuffer) Write(b []byte) (int, error) {
n, err := h.Hash.Write(b)
h.B = append(h.B, b[:n]...)
return n, err
}
func (h *hashBuffer) Reset() {
h.Hash.Reset()
h.B = h.B[:0]
}
func FuzzTime(f *testing.F) {
f.Add(int64(0), int64(0), false, "", 0, int64(0), int64(0), false, "", 0)
f.Add(int64(0), int64(0), false, "", 0, int64(0), int64(0), true, "", 0)
f.Add(int64(0), int64(0), false, "", 0, int64(0), int64(0), true, "hello", 0)
f.Add(int64(0), int64(0), false, "", 0, int64(0), int64(0), true, "", 1234)
f.Add(int64(0), int64(0), false, "", 0, int64(0), int64(0), true, "hello", 1234)
f.Add(int64(0), int64(0), false, "", 0, int64(0), int64(1), false, "", 0)
f.Add(int64(0), int64(0), false, "", 0, int64(0), int64(1), true, "", 0)
f.Add(int64(0), int64(0), false, "", 0, int64(0), int64(1), true, "hello", 0)
f.Add(int64(0), int64(0), false, "", 0, int64(0), int64(1), true, "", 1234)
f.Add(int64(0), int64(0), false, "", 0, int64(0), int64(1), true, "hello", 1234)
f.Add(int64(math.MaxInt64), int64(math.MaxInt64), false, "", 0, int64(math.MaxInt64), int64(math.MaxInt64), false, "", 0)
f.Add(int64(math.MaxInt64), int64(math.MaxInt64), false, "", 0, int64(math.MaxInt64), int64(math.MaxInt64), true, "", 0)
f.Add(int64(math.MaxInt64), int64(math.MaxInt64), false, "", 0, int64(math.MaxInt64), int64(math.MaxInt64), true, "hello", 0)
f.Add(int64(math.MaxInt64), int64(math.MaxInt64), false, "", 0, int64(math.MaxInt64), int64(math.MaxInt64), true, "", 1234)
f.Add(int64(math.MaxInt64), int64(math.MaxInt64), false, "", 0, int64(math.MaxInt64), int64(math.MaxInt64), true, "hello", 1234)
f.Add(int64(math.MinInt64), int64(math.MinInt64), false, "", 0, int64(math.MinInt64), int64(math.MinInt64), false, "", 0)
f.Add(int64(math.MinInt64), int64(math.MinInt64), false, "", 0, int64(math.MinInt64), int64(math.MinInt64), true, "", 0)
f.Add(int64(math.MinInt64), int64(math.MinInt64), false, "", 0, int64(math.MinInt64), int64(math.MinInt64), true, "hello", 0)
f.Add(int64(math.MinInt64), int64(math.MinInt64), false, "", 0, int64(math.MinInt64), int64(math.MinInt64), true, "", 1234)
f.Add(int64(math.MinInt64), int64(math.MinInt64), false, "", 0, int64(math.MinInt64), int64(math.MinInt64), true, "hello", 1234)
f.Fuzz(func(t *testing.T,
s1, ns1 int64, loc1 bool, name1 string, off1 int,
s2, ns2 int64, loc2 bool, name2 string, off2 int,
) {
t1 := time.Unix(s1, ns1)
if loc1 {
t1.In(time.FixedZone(name1, off1))
}
t2 := time.Unix(s2, ns2)
if loc2 {
t2.In(time.FixedZone(name2, off2))
}
got := Hash(&t1) == Hash(&t2)
want := t1.Format(time.RFC3339Nano) == t2.Format(time.RFC3339Nano)
if got != want {
t.Errorf("time.Time(%s) == time.Time(%s) mismatches hash equivalent", t1.Format(time.RFC3339Nano), t2.Format(time.RFC3339Nano))
}
})
}
func FuzzAddr(f *testing.F) {
f.Fuzz(func(t *testing.T,
u1a, u1b uint64, zone1 string,
u2a, u2b uint64, zone2 string,
) {
var b1, b2 [16]byte
binary.LittleEndian.PutUint64(b1[:8], u1a)
binary.LittleEndian.PutUint64(b1[8:], u1b)
binary.LittleEndian.PutUint64(b2[:8], u2a)
binary.LittleEndian.PutUint64(b2[8:], u2b)
var ips [4]netip.Addr
ips[0] = netip.AddrFrom4(*(*[4]byte)(b1[:]))
ips[1] = netip.AddrFrom4(*(*[4]byte)(b2[:]))
ips[2] = netip.AddrFrom16(b1)
if zone1 != "" {
ips[2] = ips[2].WithZone(zone1)
}
ips[3] = netip.AddrFrom16(b2)
if zone2 != "" {
ips[3] = ips[2].WithZone(zone2)
}
for _, ip1 := range ips[:] {
for _, ip2 := range ips[:] {
got := Hash(&ip1) == Hash(&ip2)
want := ip1 == ip2
if got != want {
t.Errorf("netip.Addr(%s) == netip.Addr(%s) mismatches hash equivalent", ip1.String(), ip2.String())
}
}
}
})
}
func TestAppendTo(t *testing.T) {
v := getVal()
h := Hash(v)
sum := h.AppendTo(nil)
if s := h.String(); s != string(sum) {
t.Errorf("hash sum mismatch; h.String()=%q h.AppendTo()=%q", s, string(sum))
}
}
func BenchmarkAppendTo(b *testing.B) {
b.ReportAllocs()
v := getVal()
h := Hash(v)
hashBuf := make([]byte, 0, 100)
b.ResetTimer()
for i := 0; i < b.N; i++ {
hashBuf = h.AppendTo(hashBuf[:0])
}
}
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