diff options
Diffstat (limited to 'pkg/tcpip/header')
-rw-r--r-- | pkg/tcpip/header/ndp_options.go | 163 | ||||
-rw-r--r-- | pkg/tcpip/header/ndp_test.go | 360 |
2 files changed, 475 insertions, 48 deletions
diff --git a/pkg/tcpip/header/ndp_options.go b/pkg/tcpip/header/ndp_options.go index 98310ea23..a2b9d7435 100644 --- a/pkg/tcpip/header/ndp_options.go +++ b/pkg/tcpip/header/ndp_options.go @@ -16,6 +16,7 @@ package header import ( "encoding/binary" + "errors" "time" "gvisor.dev/gvisor/pkg/tcpip" @@ -30,9 +31,9 @@ const ( // Link Layer Option for an Ethernet address. ndpTargetEthernetLinkLayerAddressSize = 8 - // ndpPrefixInformationType is the type of the Prefix Information + // NDPPrefixInformationType is the type of the Prefix Information // option, as per RFC 4861 section 4.6.2. - ndpPrefixInformationType = 3 + NDPPrefixInformationType = 3 // ndpPrefixInformationLength is the expected length, in bytes, of the // body of an NDP Prefix Information option, as per RFC 4861 section @@ -95,9 +96,122 @@ const ( lengthByteUnits = 8 ) +// NDPOptionIterator is an iterator of NDPOption. +// +// Note, between when an NDPOptionIterator is obtained and last used, no changes +// to the NDPOptions may happen. Doing so may cause undefined and unexpected +// behaviour. It is fine to obtain an NDPOptionIterator, iterate over the first +// few NDPOption then modify the backing NDPOptions so long as the +// NDPOptionIterator obtained before modification is no longer used. +type NDPOptionIterator struct { + // The NDPOptions this NDPOptionIterator is iterating over. + opts NDPOptions +} + +// Potential errors when iterating over an NDPOptions. +var ( + ErrNDPOptBufExhausted = errors.New("Buffer unexpectedly exhausted") + ErrNDPOptZeroLength = errors.New("NDP option has zero-valued Length field") + ErrNDPOptMalformedBody = errors.New("NDP option has a malformed body") +) + +// Next returns the next element in the backing NDPOptions, or true if we are +// done, or false if an error occured. +// +// The return can be read as option, done, error. Note, option should only be +// used if done is false and error is nil. +func (i *NDPOptionIterator) Next() (NDPOption, bool, error) { + for { + // Do we still have elements to look at? + if len(i.opts) == 0 { + return nil, true, nil + } + + // Do we have enough bytes for an NDP option that has a Length + // field of at least 1? Note, 0 in the Length field is invalid. + if len(i.opts) < lengthByteUnits { + return nil, true, ErrNDPOptBufExhausted + } + + // Get the Type field. + t := i.opts[0] + + // Get the Length field. + l := i.opts[1] + + // This would indicate an erroneous NDP option as the Length + // field should never be 0. + if l == 0 { + return nil, true, ErrNDPOptZeroLength + } + + // How many bytes are in the option body? + numBytes := int(l) * lengthByteUnits + numBodyBytes := numBytes - 2 + + potentialBody := i.opts[2:] + + // This would indicate an erroenous NDPOptions buffer as we ran + // out of the buffer in the middle of an NDP option. + if left := len(potentialBody); left < numBodyBytes { + return nil, true, ErrNDPOptBufExhausted + } + + // Get only the options body, leaving the rest of the options + // buffer alone. + body := potentialBody[:numBodyBytes] + + // Update opts with the remaining options body. + i.opts = i.opts[numBytes:] + + switch t { + case NDPTargetLinkLayerAddressOptionType: + return NDPTargetLinkLayerAddressOption(body), false, nil + + case NDPPrefixInformationType: + // Make sure the length of a Prefix Information option + // body is ndpPrefixInformationLength, as per RFC 4861 + // section 4.6.2. + if numBodyBytes != ndpPrefixInformationLength { + return nil, true, ErrNDPOptMalformedBody + } + + return NDPPrefixInformation(body), false, nil + default: + // We do not yet recognize the option, just skip for + // now. This is okay because RFC 4861 allows us to + // skip/ignore any unrecognized options. However, + // we MUST recognized all the options in RFC 4861. + // + // TODO(b/141487990): Handle all NDP options as defined + // by RFC 4861. + } + } +} + // NDPOptions is a buffer of NDP options as defined by RFC 4861 section 4.6. type NDPOptions []byte +// Iter returns an iterator of NDPOption. +// +// If check is true, Iter will do an integrity check on the options by iterating +// over it and returning an error if detected. +// +// See NDPOptionIterator for more information. +func (b NDPOptions) Iter(check bool) (NDPOptionIterator, error) { + it := NDPOptionIterator{opts: b} + + if check { + for it2 := it; true; { + if _, done, err := it2.Next(); err != nil || done { + return it, err + } + } + } + + return it, nil +} + // Serialize serializes the provided list of NDP options into o. // // Note, b must be of sufficient size to hold all the options in s. See @@ -137,15 +251,15 @@ func (b NDPOptions) Serialize(s NDPOptionsSerializer) int { return done } -// ndpOption is the set of functions to be implemented by all NDP option types. -type ndpOption interface { - // Type returns the type of this ndpOption. +// NDPOption is the set of functions to be implemented by all NDP option types. +type NDPOption interface { + // Type returns the type of the receiver. Type() uint8 - // Length returns the length of the body of this ndpOption, in bytes. + // Length returns the length of the body of the receiver, in bytes. Length() int - // serializeInto serializes this ndpOption into the provided byte + // serializeInto serializes the receiver into the provided byte // buffer. // // Note, the caller MUST provide a byte buffer with size of at least @@ -154,15 +268,15 @@ type ndpOption interface { // buffer is not of sufficient size. // // serializeInto will return the number of bytes that was used to - // serialize this ndpOption. Implementers must only use the number of - // bytes required to serialize this ndpOption. Callers MAY provide a + // serialize the receiver. Implementers must only use the number of + // bytes required to serialize the receiver. Callers MAY provide a // larger buffer than required to serialize into. serializeInto([]byte) int } // paddedLength returns the length of o, in bytes, with any padding bytes, if // required. -func paddedLength(o ndpOption) int { +func paddedLength(o NDPOption) int { l := o.Length() if l == 0 { @@ -201,7 +315,7 @@ func paddedLength(o ndpOption) int { } // NDPOptionsSerializer is a serializer for NDP options. -type NDPOptionsSerializer []ndpOption +type NDPOptionsSerializer []NDPOption // Length returns the total number of bytes required to serialize. func (b NDPOptionsSerializer) Length() int { @@ -221,21 +335,34 @@ func (b NDPOptionsSerializer) Length() int { // where X is the value in Length multiplied by lengthByteUnits - 2 bytes. type NDPTargetLinkLayerAddressOption tcpip.LinkAddress -// Type implements ndpOption.Type. +// Type implements NDPOption.Type. func (o NDPTargetLinkLayerAddressOption) Type() uint8 { return NDPTargetLinkLayerAddressOptionType } -// Length implements ndpOption.Length. +// Length implements NDPOption.Length. func (o NDPTargetLinkLayerAddressOption) Length() int { return len(o) } -// serializeInto implements ndpOption.serializeInto. +// serializeInto implements NDPOption.serializeInto. func (o NDPTargetLinkLayerAddressOption) serializeInto(b []byte) int { return copy(b, o) } +// EthernetAddress will return an ethernet (MAC) address if the +// NDPTargetLinkLayerAddressOption's body has at minimum EthernetAddressSize +// bytes. If the body has more than EthernetAddressSize bytes, only the first +// EthernetAddressSize bytes are returned as that is all that is needed for an +// Ethernet address. +func (o NDPTargetLinkLayerAddressOption) EthernetAddress() tcpip.LinkAddress { + if len(o) >= EthernetAddressSize { + return tcpip.LinkAddress(o[:EthernetAddressSize]) + } + + return tcpip.LinkAddress([]byte(nil)) +} + // NDPPrefixInformation is the NDP Prefix Information option as defined by // RFC 4861 section 4.6.2. // @@ -243,17 +370,17 @@ func (o NDPTargetLinkLayerAddressOption) serializeInto(b []byte) int { // ndpPrefixInformationLength bytes. type NDPPrefixInformation []byte -// Type implements ndpOption.Type. +// Type implements NDPOption.Type. func (o NDPPrefixInformation) Type() uint8 { - return ndpPrefixInformationType + return NDPPrefixInformationType } -// Length implements ndpOption.Length. +// Length implements NDPOption.Length. func (o NDPPrefixInformation) Length() int { return ndpPrefixInformationLength } -// serializeInto implements ndpOption.serializeInto. +// serializeInto implements NDPOption.serializeInto. func (o NDPPrefixInformation) serializeInto(b []byte) int { used := copy(b, o) diff --git a/pkg/tcpip/header/ndp_test.go b/pkg/tcpip/header/ndp_test.go index 0bbf67a2b..ad6daafcd 100644 --- a/pkg/tcpip/header/ndp_test.go +++ b/pkg/tcpip/header/ndp_test.go @@ -36,18 +36,18 @@ func TestNDPNeighborSolicit(t *testing.T) { ns := NDPNeighborSolicit(b) addr := tcpip.Address("\x01\x02\x03\x04\x05\x06\x07\x08\x09\x0a\x0b\x0c\x0d\x0e\x0f\x10") if got := ns.TargetAddress(); got != addr { - t.Fatalf("got ns.TargetAddress = %s, want %s", got, addr) + t.Errorf("got ns.TargetAddress = %s, want %s", got, addr) } // Test updating the Target Address. addr2 := tcpip.Address("\x11\x12\x13\x14\x15\x16\x17\x18\x19\x1a\x1b\x1c\x1d\x1e\x1f\x11") ns.SetTargetAddress(addr2) if got := ns.TargetAddress(); got != addr2 { - t.Fatalf("got ns.TargetAddress = %s, want %s", got, addr2) + t.Errorf("got ns.TargetAddress = %s, want %s", got, addr2) } // Make sure the address got updated in the backing buffer. if got := tcpip.Address(b[ndpNSTargetAddessOffset:][:IPv6AddressSize]); got != addr2 { - t.Fatalf("got targetaddress buffer = %s, want %s", got, addr2) + t.Errorf("got targetaddress buffer = %s, want %s", got, addr2) } } @@ -65,56 +65,56 @@ func TestNDPNeighborAdvert(t *testing.T) { na := NDPNeighborAdvert(b) addr := tcpip.Address("\x01\x02\x03\x04\x05\x06\x07\x08\x09\x0a\x0b\x0c\x0d\x0e\x0f\x10") if got := na.TargetAddress(); got != addr { - t.Fatalf("got TargetAddress = %s, want %s", got, addr) + t.Errorf("got TargetAddress = %s, want %s", got, addr) } // Test getting the Router Flag. if got := na.RouterFlag(); !got { - t.Fatalf("got RouterFlag = false, want = true") + t.Errorf("got RouterFlag = false, want = true") } // Test getting the Solicited Flag. if got := na.SolicitedFlag(); got { - t.Fatalf("got SolicitedFlag = true, want = false") + t.Errorf("got SolicitedFlag = true, want = false") } // Test getting the Override Flag. if got := na.OverrideFlag(); !got { - t.Fatalf("got OverrideFlag = false, want = true") + t.Errorf("got OverrideFlag = false, want = true") } // Test updating the Target Address. addr2 := tcpip.Address("\x11\x12\x13\x14\x15\x16\x17\x18\x19\x1a\x1b\x1c\x1d\x1e\x1f\x11") na.SetTargetAddress(addr2) if got := na.TargetAddress(); got != addr2 { - t.Fatalf("got TargetAddress = %s, want %s", got, addr2) + t.Errorf("got TargetAddress = %s, want %s", got, addr2) } // Make sure the address got updated in the backing buffer. if got := tcpip.Address(b[ndpNATargetAddressOffset:][:IPv6AddressSize]); got != addr2 { - t.Fatalf("got targetaddress buffer = %s, want %s", got, addr2) + t.Errorf("got targetaddress buffer = %s, want %s", got, addr2) } // Test updating the Router Flag. na.SetRouterFlag(false) if got := na.RouterFlag(); got { - t.Fatalf("got RouterFlag = true, want = false") + t.Errorf("got RouterFlag = true, want = false") } // Test updating the Solicited Flag. na.SetSolicitedFlag(true) if got := na.SolicitedFlag(); !got { - t.Fatalf("got SolicitedFlag = false, want = true") + t.Errorf("got SolicitedFlag = false, want = true") } // Test updating the Override Flag. na.SetOverrideFlag(false) if got := na.OverrideFlag(); got { - t.Fatalf("got OverrideFlag = true, want = false") + t.Errorf("got OverrideFlag = true, want = false") } // Make sure flags got updated in the backing buffer. if got := b[ndpNAFlagsOffset]; got != 64 { - t.Fatalf("got flags byte = %d, want = 64") + t.Errorf("got flags byte = %d, want = 64") } } @@ -128,30 +128,66 @@ func TestNDPRouterAdvert(t *testing.T) { ra := NDPRouterAdvert(b) if got := ra.CurrHopLimit(); got != 64 { - t.Fatalf("got ra.CurrHopLimit = %d, want = 64", got) + t.Errorf("got ra.CurrHopLimit = %d, want = 64", got) } if got := ra.ManagedAddrConfFlag(); !got { - t.Fatalf("got ManagedAddrConfFlag = false, want = true") + t.Errorf("got ManagedAddrConfFlag = false, want = true") } if got := ra.OtherConfFlag(); got { - t.Fatalf("got OtherConfFlag = true, want = false") + t.Errorf("got OtherConfFlag = true, want = false") } if got, want := ra.RouterLifetime(), time.Second*258; got != want { - t.Fatalf("got ra.RouterLifetime = %d, want = %d", got, want) + t.Errorf("got ra.RouterLifetime = %d, want = %d", got, want) } if got, want := ra.ReachableTime(), time.Millisecond*50595078; got != want { - t.Fatalf("got ra.ReachableTime = %d, want = %d", got, want) + t.Errorf("got ra.ReachableTime = %d, want = %d", got, want) } if got, want := ra.RetransTimer(), time.Millisecond*117967114; got != want { - t.Fatalf("got ra.RetransTimer = %d, want = %d", got, want) + t.Errorf("got ra.RetransTimer = %d, want = %d", got, want) } } +// TestNDPTargetLinkLayerAddressOptionEthernetAddress tests getting the +// Ethernet address from an NDPTargetLinkLayerAddressOption. +func TestNDPTargetLinkLayerAddressOptionEthernetAddress(t *testing.T) { + tests := []struct { + name string + buf []byte + expected tcpip.LinkAddress + }{ + { + "ValidMAC", + []byte{1, 2, 3, 4, 5, 6}, + tcpip.LinkAddress("\x01\x02\x03\x04\x05\x06"), + }, + { + "TLLBodyTooShort", + []byte{1, 2, 3, 4, 5}, + tcpip.LinkAddress([]byte(nil)), + }, + { + "TLLBodyLargerThanNeeded", + []byte{1, 2, 3, 4, 5, 6, 7, 8}, + tcpip.LinkAddress("\x01\x02\x03\x04\x05\x06"), + }, + } + + for _, test := range tests { + t.Run(test.name, func(t *testing.T) { + tll := NDPTargetLinkLayerAddressOption(test.buf) + if got := tll.EthernetAddress(); got != test.expected { + t.Errorf("got tll.EthernetAddress = %s, want = %s", got, test.expected) + } + }) + } + +} + // TestNDPTargetLinkLayerAddressOptionSerialize tests serializing a // NDPTargetLinkLayerAddressOption. func TestNDPTargetLinkLayerAddressOptionSerialize(t *testing.T) { @@ -194,6 +230,44 @@ func TestNDPTargetLinkLayerAddressOptionSerialize(t *testing.T) { if !bytes.Equal(test.buf, test.expectedBuf) { t.Fatalf("got b = %d, want = %d", test.buf, test.expectedBuf) } + + it, err := opts.Iter(true) + if err != nil { + t.Fatalf("got Iter = (_, %s), want = (_, nil)", err) + } + + if len(test.expectedBuf) > 0 { + next, done, err := it.Next() + if err != nil { + t.Fatalf("got Next = (_, _, %s), want = (_, _, nil)", err) + } + if done { + t.Fatal("got Next = (_, true, _), want = (_, false, _)") + } + if got := next.Type(); got != NDPTargetLinkLayerAddressOptionType { + t.Fatalf("got Type %= %d, want = %d", got, NDPTargetLinkLayerAddressOptionType) + } + tll := next.(NDPTargetLinkLayerAddressOption) + if got, want := []byte(tll), test.expectedBuf[2:]; !bytes.Equal(got, want) { + t.Fatalf("got Next = (%x, _, _), want = (%x, _, _)", got, want) + } + + if got, want := tll.EthernetAddress(), tcpip.LinkAddress(test.expectedBuf[2:][:EthernetAddressSize]); got != want { + t.Errorf("got tll.MACAddress = %s, want = %s", got, want) + } + } + + // Iterator should not return anything else. + next, done, err := it.Next() + if err != nil { + t.Errorf("got Next = (_, _, %s), want = (_, _, nil)", err) + } + if !done { + t.Error("got Next = (_, false, _), want = (_, true, _)") + } + if next != nil { + t.Errorf("got Next = (%x, _, _), want = (nil, _, _)", next) + } }) } } @@ -232,39 +306,265 @@ func TestNDPPrefixInformationOption(t *testing.T) { t.Fatalf("got targetBuf = %x, want = %x", targetBuf, expectedBuf) } - // First two bytes are the Type and Length fields, which are not part of - // the option body. - pi := NDPPrefixInformation(targetBuf[2:]) + it, err := opts.Iter(true) + if err != nil { + t.Fatalf("got Iter = (_, %s), want = (_, nil)", err) + } + + next, done, err := it.Next() + if err != nil { + t.Fatalf("got Next = (_, _, %s), want = (_, _, nil)", err) + } + if done { + t.Fatal("got Next = (_, true, _), want = (_, false, _)") + } + if got := next.Type(); got != NDPPrefixInformationType { + t.Errorf("got Type = %d, want = %d", got, NDPPrefixInformationType) + } + + pi := next.(NDPPrefixInformation) if got := pi.Type(); got != 3 { - t.Fatalf("got Type = %d, want = 3", got) + t.Errorf("got Type = %d, want = 3", got) } if got := pi.Length(); got != 30 { - t.Fatalf("got Length = %d, want = 30", got) + t.Errorf("got Length = %d, want = 30", got) } if got := pi.PrefixLength(); got != 43 { - t.Fatalf("got PrefixLength = %d, want = 43", got) + t.Errorf("got PrefixLength = %d, want = 43", got) } if pi.OnLinkFlag() { - t.Fatalf("got OnLinkFlag = true, want = false") + t.Error("got OnLinkFlag = true, want = false") } if !pi.AutonomousAddressConfigurationFlag() { - t.Fatalf("got AutonomousAddressConfigurationFlag = false, want = true") + t.Error("got AutonomousAddressConfigurationFlag = false, want = true") } if got, want := pi.ValidLifetime(), 16909060*time.Second; got != want { - t.Fatalf("got ValidLifetime = %d, want = %d", got, want) + t.Errorf("got ValidLifetime = %d, want = %d", got, want) } if got, want := pi.PreferredLifetime(), 84281096*time.Second; got != want { - t.Fatalf("got PreferredLifetime = %d, want = %d", got, want) + t.Errorf("got PreferredLifetime = %d, want = %d", got, want) } if got, want := pi.Prefix(), tcpip.Address("\x09\x0a\x0b\x0c\x0d\x0e\x0f\x10\x11\x12\x13\x14\x15\x16\x17\x18"); got != want { - t.Fatalf("got Prefix = %s, want = %s", got, want) + t.Errorf("got Prefix = %s, want = %s", got, want) + } + + // Iterator should not return anything else. + next, done, err = it.Next() + if err != nil { + t.Errorf("got Next = (_, _, %s), want = (_, _, nil)", err) + } + if !done { + t.Error("got Next = (_, false, _), want = (_, true, _)") + } + if next != nil { + t.Errorf("got Next = (%x, _, _), want = (nil, _, _)", next) + } +} + +// TestNDPOptionsIterCheck tests that Iter will return false if the NDPOptions +// the iterator was returned for is malformed. +func TestNDPOptionsIterCheck(t *testing.T) { + tests := []struct { + name string + buf []byte + expected error + }{ + { + "ZeroLengthField", + []byte{0, 0, 0, 0, 0, 0, 0, 0}, + ErrNDPOptZeroLength, + }, + { + "ValidTargetLinkLayerAddressOption", + []byte{2, 1, 1, 2, 3, 4, 5, 6}, + nil, + }, + { + "TooSmallTargetLinkLayerAddressOption", + []byte{2, 1, 1, 2, 3, 4, 5}, + ErrNDPOptBufExhausted, + }, + { + "ValidPrefixInformation", + []byte{ + 3, 4, 43, 64, + 1, 2, 3, 4, + 5, 6, 7, 8, + 0, 0, 0, 0, + 9, 10, 11, 12, + 13, 14, 15, 16, + 17, 18, 19, 20, + 21, 22, 23, 24, + }, + nil, + }, + { + "TooSmallPrefixInformation", + []byte{ + 3, 4, 43, 64, + 1, 2, 3, 4, + 5, 6, 7, 8, + 0, 0, 0, 0, + 9, 10, 11, 12, + 13, 14, 15, 16, + 17, 18, 19, 20, + 21, 22, 23, + }, + ErrNDPOptBufExhausted, + }, + { + "InvalidPrefixInformationLength", + []byte{ + 3, 3, 43, 64, + 1, 2, 3, 4, + 5, 6, 7, 8, + 0, 0, 0, 0, + 9, 10, 11, 12, + 13, 14, 15, 16, + }, + ErrNDPOptMalformedBody, + }, + { + "ValidTargetLinkLayerAddressWithPrefixInformation", + []byte{ + // Target Link-Layer Address. + 2, 1, 1, 2, 3, 4, 5, 6, + + // Prefix information. + 3, 4, 43, 64, + 1, 2, 3, 4, + 5, 6, 7, 8, + 0, 0, 0, 0, + 9, 10, 11, 12, + 13, 14, 15, 16, + 17, 18, 19, 20, + 21, 22, 23, 24, + }, + nil, + }, + { + "ValidTargetLinkLayerAddressWithPrefixInformationWithUnrecognized", + []byte{ + // Target Link-Layer Address. + 2, 1, 1, 2, 3, 4, 5, 6, + + // 255 is an unrecognized type. If 255 ends up + // being the type for some recognized type, + // update 255 to some other unrecognized value. + 255, 2, 1, 2, 3, 4, 5, 6, 1, 2, 3, 4, 5, 6, 7, 8, + + // Prefix information. + 3, 4, 43, 64, + 1, 2, 3, 4, + 5, 6, 7, 8, + 0, 0, 0, 0, + 9, 10, 11, 12, + 13, 14, 15, 16, + 17, 18, 19, 20, + 21, 22, 23, 24, + }, + nil, + }, + } + + for _, test := range tests { + t.Run(test.name, func(t *testing.T) { + opts := NDPOptions(test.buf) + + if _, err := opts.Iter(true); err != test.expected { + t.Fatalf("got Iter(true) = (_, %v), want = (_, %v)", err, test.expected) + } + + // test.buf may be malformed but we chose not to check + // the iterator so it must return true. + if _, err := opts.Iter(false); err != nil { + t.Fatalf("got Iter(false) = (_, %s), want = (_, nil)", err) + } + }) + } +} + +// TestNDPOptionsIter tests that we can iterator over a valid NDPOptions. Note, +// this test does not actually check any of the option's getters, it simply +// checks the option Type and Body. We have other tests that tests the option +// field gettings given an option body and don't need to duplicate those tests +// here. +func TestNDPOptionsIter(t *testing.T) { + buf := []byte{ + // Target Link-Layer Address. + 2, 1, 1, 2, 3, 4, 5, 6, + + // 255 is an unrecognized type. If 255 ends up being the type + // for some recognized type, update 255 to some other + // unrecognized value. Note, this option should be skipped when + // iterating. + 255, 2, 1, 2, 3, 4, 5, 6, 1, 2, 3, 4, 5, 6, 7, 8, + + // Prefix information. + 3, 4, 43, 64, + 1, 2, 3, 4, + 5, 6, 7, 8, + 0, 0, 0, 0, + 9, 10, 11, 12, + 13, 14, 15, 16, + 17, 18, 19, 20, + 21, 22, 23, 24, + } + + opts := NDPOptions(buf) + it, err := opts.Iter(true) + if err != nil { + t.Fatalf("got Iter = (_, %s), want = (_, nil)", err) + } + + // Test the first (Taret Link-Layer) option. + next, done, err := it.Next() + if err != nil { + t.Fatalf("got Next = (_, _, %s), want = (_, _, nil)", err) + } + if done { + t.Fatal("got Next = (_, true, _), want = (_, false, _)") + } + if got, want := []byte(next.(NDPTargetLinkLayerAddressOption)), buf[2:][:6]; !bytes.Equal(got, want) { + t.Errorf("got Next = (%x, _, _), want = (%x, _, _)", got, want) + } + if got := next.Type(); got != NDPTargetLinkLayerAddressOptionType { + t.Errorf("got Type = %d, want = %d", got, NDPTargetLinkLayerAddressOptionType) + } + + // Test the next (Prefix Information) option. + // Note, the unrecognized option should be skipped. + next, done, err = it.Next() + if err != nil { + t.Fatalf("got Next = (_, _, %s), want = (_, _, nil)", err) + } + if done { + t.Fatal("got Next = (_, true, _), want = (_, false, _)") + } + if got, want := next.(NDPPrefixInformation), buf[26:][:30]; !bytes.Equal(got, want) { + t.Errorf("got Next = (%x, _, _), want = (%x, _, _)", got, want) + } + if got := next.Type(); got != NDPPrefixInformationType { + t.Errorf("got Type = %d, want = %d", got, NDPPrefixInformationType) + } + + // Iterator should not return anything else. + next, done, err = it.Next() + if err != nil { + t.Errorf("got Next = (_, _, %s), want = (_, _, nil)", err) + } + if !done { + t.Error("got Next = (_, false, _), want = (_, true, _)") + } + if next != nil { + t.Errorf("got Next = (%x, _, _), want = (nil, _, _)", next) } } |