// 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" "bufio" "bytes" "crypto/sha256" "fmt" "io" "math" "math/rand" "reflect" "runtime" "testing" "testing/quick" "time" "unsafe" "go4.org/mem" "tailscale.com/net/netaddr" "tailscale.com/tailcfg" "tailscale.com/types/dnstype" "tailscale.com/types/ipproto" "tailscale.com/types/key" "tailscale.com/types/structs" "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{[]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, }, } 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++ { hash2 := Hash(getVal()) 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) } } func getVal() []any { return []any{ &wgcfg.Config{ Name: "foo", Addresses: []netaddr.IPPrefix{netaddr.IPPrefixFrom(netaddr.IPFrom16([16]byte{3: 3}), 5)}, Peers: []wgcfg.Peer{ { PublicKey: key.NodePublic{}, }, }, }, &router.Config{ Routes: []netaddr.IPPrefix{ netaddr.MustParseIPPrefix("1.2.3.0/24"), netaddr.MustParseIPPrefix("1234::/64"), }, }, map[dnsname.FQDN][]netaddr.IP{ dnsname.FQDN("a."): {netaddr.MustParseIP("1.2.3.4"), netaddr.MustParseIP("4.3.2.1")}, dnsname.FQDN("b."): {netaddr.MustParseIP("8.8.8.8"), netaddr.MustParseIP("9.9.9.9")}, dnsname.FQDN("c."): {netaddr.MustParseIP("6.6.6.6"), netaddr.MustParseIP("7.7.7.7")}, dnsname.FQDN("d."): {netaddr.MustParseIP("6.7.6.6"), netaddr.MustParseIP("7.7.7.8")}, dnsname.FQDN("e."): {netaddr.MustParseIP("6.8.6.6"), netaddr.MustParseIP("7.7.7.9")}, dnsname.FQDN("f."): {netaddr.MustParseIP("6.9.6.6"), netaddr.MustParseIP("7.7.7.0")}, }, map[dnsname.FQDN][]netaddr.IPPort{ dnsname.FQDN("a."): {netaddr.MustParseIPPort("1.2.3.4:11"), netaddr.MustParseIPPort("4.3.2.1:22")}, dnsname.FQDN("b."): {netaddr.MustParseIPPort("8.8.8.8:11"), netaddr.MustParseIPPort("9.9.9.9:22")}, dnsname.FQDN("c."): {netaddr.MustParseIPPort("8.8.8.8:12"), netaddr.MustParseIPPort("9.9.9.9:23")}, dnsname.FQDN("d."): {netaddr.MustParseIPPort("8.8.8.8:13"), netaddr.MustParseIPPort("9.9.9.9:24")}, dnsname.FQDN("e."): {netaddr.MustParseIPPort("8.8.8.8:14"), netaddr.MustParseIPPort("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}, }, } } func TestTypeIsRecursive(t *testing.T) { type RecursiveStruct struct { v *RecursiveStruct } type RecursiveChan chan *RecursiveChan tests := []struct { val any want bool }{ {val: 42, want: false}, {val: "string", want: false}, {val: 1 + 2i, want: false}, {val: struct{}{}, want: false}, {val: (*RecursiveStruct)(nil), want: true}, {val: RecursiveStruct{}, want: true}, {val: time.Unix(0, 0), want: false}, {val: structs.Incomparable{}, want: false}, // ignore its [0]func() {val: tailcfg.NetPortRange{}, want: false}, // uses structs.Incomparable {val: (*tailcfg.Node)(nil), want: false}, {val: map[string]bool{}, want: false}, {val: func() {}, want: false}, {val: make(chan int), want: false}, {val: unsafe.Pointer(nil), want: false}, {val: make(RecursiveChan), want: true}, {val: make(chan int), want: false}, } for _, tt := range tests { got := typeIsRecursive(reflect.TypeOf(tt.val)) if got != tt.want { t.Errorf("for type %T: got %v, want %v", tt.val, got, tt.want) } } } 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 TestCanMemHash(t *testing.T) { tests := []struct { val any want bool }{ {true, true}, {uint(1), true}, {uint8(1), true}, {uint16(1), true}, {uint32(1), true}, {uint64(1), true}, {uintptr(1), true}, {int(1), true}, {int8(1), true}, {int16(1), true}, {int32(1), true}, {int64(1), true}, {float32(1), true}, {float64(1), true}, {complex64(1), true}, {complex128(1), true}, {[32]byte{}, true}, {func() {}, false}, {make(chan int), false}, {struct{ io.Writer }{nil}, false}, {unsafe.Pointer(nil), false}, {new(int), false}, {TwoInts{}, true}, {[4]TwoInts{}, true}, {IntThenByte{}, false}, {[4]IntThenByte{}, false}, {tailcfg.PortRange{}, true}, {int16(0), true}, {struct { _ int _ int }{}, true}, {struct { _ int _ uint8 _ int }{}, false}, // gap { struct { _ structs.Incomparable // if not last, zero-width x int }{}, true, }, { struct { x int _ structs.Incomparable // zero-width last: has space, can't memhash }{}, false, }} for _, tt := range tests { got := canMemHash(reflect.TypeOf(tt.val)) if got != tt.want { t.Errorf("for type %T: got %v, want %v", tt.val, got, tt.want) } } } 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 = netaddr.MustParseIP("1.2.3.4") ) tests := []struct { name string val any want bool // set true automatically if out != "" out string out32 string // overwrites out if 32-bit }{ { name: "int", val: int(1), out: "\x01\x00\x00\x00\x00\x00\x00\x00", }, { name: "int_negative", val: int(-1), out: "\xff\xff\xff\xff\xff\xff\xff\xff", }, { 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: "\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: "\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: "\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", }, { 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: "\x04\x00\x00\x00\x00\x00\x00\x00\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\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\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\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\x00\x00\x00\x00\x00\x00\x00\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\x03\x00\x00\x00\x00\x00\x00\x00foo\x01\x00\x00\x00\x00\x00\x00\x00\v\x00\x00\x00\x00\x00\x00\x00foooooooooo\x00\x00\x00\x00\x00\x00\x00\x00\x01\x00\x00\x00\x00\x00\x00\x00\f\x00\x00\x00\x00\x00\x00\x00baaaaaarrrrr\x00\x01\x00\x02\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x01\x00\x00\x00\x00\x00\x00\x00\v\x00\x00\x00\x00\x00\x00\x00foooooooooo\x00\x00\x00\x00\x00\x00\x00\x00\x01\x00\x00\x00\x00\x00\x00\x00\f\x00\x00\x00\x00\x00\x00\x00baaaaaarrrrr\x00\x01\x00\x02\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x01\x00\x00\x00\x00\x00\x00\x00\v\x00\x00\x00\x00\x00\x00\x00foooooooooo\x00\x00\x00\x00\x00\x00\x00\x00\x01\x00\x00\x00\x00\x00\x00\x00\f\x00\x00\x00\x00\x00\x00\x00baaaaaarrrrr\x00\x01\x00\x02\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00", out32: "\x04\x00\x00\x00\x00\x00\x00\x00\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\x03\x00\x00\x00\x00\x00\x00\x00\x01\x00\x00\x00\x02\x00\x00\x00\x03\x00\x00\x00\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\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\x00\x00\x00\x00\x00\x00\x00\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\x03\x00\x00\x00\x00\x00\x00\x00foo\x01\x00\x00\x00\x00\x00\x00\x00\v\x00\x00\x00\x00\x00\x00\x00foooooooooo\x00\x00\x00\x00\x00\x00\x00\x00\x01\x00\x00\x00\x00\x00\x00\x00\f\x00\x00\x00\x00\x00\x00\x00baaaaaarrrrr\x00\x01\x00\x02\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x01\x00\x00\x00\x00\x00\x00\x00\v\x00\x00\x00\x00\x00\x00\x00foooooooooo\x00\x00\x00\x00\x00\x00\x00\x00\x01\x00\x00\x00\x00\x00\x00\x00\f\x00\x00\x00\x00\x00\x00\x00baaaaaarrrrr\x00\x01\x00\x02\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x01\x00\x00\x00\x00\x00\x00\x00\v\x00\x00\x00\x00\x00\x00\x00foooooooooo\x00\x00\x00\x00\x00\x00\x00\x00\x01\x00\x00\x00\x00\x00\x00\x00\f\x00\x00\x00\x00\x00\x00\x00baaaaaarrrrr\x00\x01\x00\x02\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00", }, { name: "netaddr.IP", val: netaddr.MustParseIP("fe80::123%foo"), out: "\r\x00\x00\x00\x00\x00\x00\x00fe80::123%foo", }, { name: "ptr-netaddr.IP", val: &someIP, out: "\x01\a\x00\x00\x00\x00\x00\x00\x001.2.3.4", }, { name: "ptr-nil-netaddr.IP", val: (*netaddr.IP)(nil), out: "\x00", }, { name: "time", val: time.Unix(0, 0).In(time.UTC), out: "\x141970-01-01T00:00:00Z", }, { name: "time_custom_zone", val: time.Unix(1655311822, 0).In(time.FixedZone("FOO", -60*60)), out: "\x192022-06-15T15:50:22-01:00", }, { 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: ptrTo([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-canddr", 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\x140001-01-01T00:00:00Z\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\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x140001-01-01T00:00:00Z\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", }, } for _, tt := range tests { t.Run(tt.name, func(t *testing.T) { rv := reflect.ValueOf(tt.val) fn := getTypeInfo(rv.Type()).hasher() var buf bytes.Buffer h := &hasher{ bw: bufio.NewWriter(&buf), } got := fn(h, rv) const ptrSize = 32 << uintptr(^uintptr(0)>>63) if tt.out32 != "" && ptrSize == 32 { tt.out = tt.out32 } if tt.out != "" { tt.want = true } if got != tt.want { t.Fatalf("func returned %v; want %v", got, tt.want) } if err := h.bw.Flush(); err != nil { t.Fatal(err) } if got := buf.String(); got != tt.out { t.Fatalf("got %q; want %q", got, tt.out) } }) } } var sink = Hash("foo") func BenchmarkHash(b *testing.B) { b.ReportAllocs() v := getVal() for i := 0; i < b.N; i++ { sink = Hash(v) } } func ptrTo[T any](v T) *T { return &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: ptrTo(32), Ports: tailcfg.PortRange{First: 1, Last: 2}, }}, IPProto: []int{1, 2, 3, 4}, CapGrant: []tailcfg.CapGrant{{ Dsts: []netaddr.IPPrefix{netaddr.MustParseIPPrefix("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() hash := HasherForType[[]tailcfg.FilterRule]() 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{} var buf bytes.Buffer bw := bufio.NewWriter(&buf) ti := getTypeInfo(reflect.TypeOf(m)) for i := 0; i < 20; i++ { v := reflect.ValueOf(m) buf.Reset() bw.Reset(&buf) h := &hasher{bw: bw} h.hashMap(v, ti, false) if got[string(buf.Bytes())] { continue } got[string(buf.Bytes())] = 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}} var got bytes.Buffer bw := bufio.NewWriter(&got) h := &hasher{bw: bw} h.hashValue(reflect.ValueOf(x), false) bw.Flush() 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 := got.Bytes(); 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) } var buf bytes.Buffer bw := bufio.NewWriter(&buf) v := reflect.ValueOf(m) ti := getTypeInfo(v.Type()) h := &hasher{bw: bw} for i := 0; i < b.N; i++ { buf.Reset() bw.Reset(&buf) h.hashMap(v, ti, false) } } 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 discrepency 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) } } 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) } }