diff options
| -rw-r--r-- | pkg/tcpip/header/ipv6_extension_headers.go | 257 | ||||
| -rw-r--r-- | pkg/tcpip/header/ipv6_extension_headers_test.go | 492 | ||||
| -rw-r--r-- | pkg/tcpip/network/ipv6/ipv6.go | 86 | ||||
| -rw-r--r-- | pkg/tcpip/network/ipv6/ipv6_test.go | 219 |
4 files changed, 980 insertions, 74 deletions
diff --git a/pkg/tcpip/header/ipv6_extension_headers.go b/pkg/tcpip/header/ipv6_extension_headers.go index b8866d4d2..1b6c3f328 100644 --- a/pkg/tcpip/header/ipv6_extension_headers.go +++ b/pkg/tcpip/header/ipv6_extension_headers.go @@ -16,6 +16,7 @@ package header import ( "bufio" + "bytes" "encoding/binary" "fmt" "io" @@ -27,6 +28,10 @@ import ( type IPv6ExtensionHeaderIdentifier uint8 const ( + // IPv6HopByHopOptionsExtHdrIdentifier is the header identifier of a Hop by + // Hop Options extension header, as per RFC 8200 section 4.3. + IPv6HopByHopOptionsExtHdrIdentifier IPv6ExtensionHeaderIdentifier = 0 + // IPv6RoutingExtHdrIdentifier is the header identifier of a Routing extension // header, as per RFC 8200 section 4.4. IPv6RoutingExtHdrIdentifier IPv6ExtensionHeaderIdentifier = 43 @@ -35,12 +40,24 @@ const ( // extension header, as per RFC 8200 section 4.5. IPv6FragmentExtHdrIdentifier IPv6ExtensionHeaderIdentifier = 44 + // IPv6DestinationOptionsExtHdrIdentifier is the header identifier of a + // Destination Options extension header, as per RFC 8200 section 4.6. + IPv6DestinationOptionsExtHdrIdentifier IPv6ExtensionHeaderIdentifier = 60 + // IPv6NoNextHeaderIdentifier is the header identifier used to signify the end // of an IPv6 payload, as per RFC 8200 section 4.7. IPv6NoNextHeaderIdentifier IPv6ExtensionHeaderIdentifier = 59 ) const ( + // ipv6UnknownExtHdrOptionActionMask is the mask of the action to take when + // a node encounters an unrecognized option. + ipv6UnknownExtHdrOptionActionMask = 192 + + // ipv6UnknownExtHdrOptionActionShift is the least significant bits to discard + // from the action value for an unrecognized option identifier. + ipv6UnknownExtHdrOptionActionShift = 6 + // ipv6RoutingExtHdrSegmentsLeftIdx is the index to the Segments Left field // within an IPv6RoutingExtHdr. ipv6RoutingExtHdrSegmentsLeftIdx = 1 @@ -107,6 +124,188 @@ type IPv6RawPayloadHeader struct { // isIPv6PayloadHeader implements IPv6PayloadHeader.isIPv6PayloadHeader. func (IPv6RawPayloadHeader) isIPv6PayloadHeader() {} +// ipv6OptionsExtHdr is an IPv6 extension header that holds options. +type ipv6OptionsExtHdr []byte + +// Iter returns an iterator over the IPv6 extension header options held in b. +func (b ipv6OptionsExtHdr) Iter() IPv6OptionsExtHdrOptionsIterator { + it := IPv6OptionsExtHdrOptionsIterator{} + it.reader.Reset(b) + return it +} + +// IPv6OptionsExtHdrOptionsIterator is an iterator over IPv6 extension header +// options. +// +// Note, between when an IPv6OptionsExtHdrOptionsIterator is obtained and last +// used, no changes to the underlying buffer may happen. Doing so may cause +// undefined and unexpected behaviour. It is fine to obtain an +// IPv6OptionsExtHdrOptionsIterator, iterate over the first few options then +// modify the backing payload so long as the IPv6OptionsExtHdrOptionsIterator +// obtained before modification is no longer used. +type IPv6OptionsExtHdrOptionsIterator struct { + reader bytes.Reader +} + +// IPv6OptionUnknownAction is the action that must be taken if the processing +// IPv6 node does not recognize the option, as outlined in RFC 8200 section 4.2. +type IPv6OptionUnknownAction int + +const ( + // IPv6OptionUnknownActionSkip indicates that the unrecognized option must + // be skipped and the node should continue processing the header. + IPv6OptionUnknownActionSkip IPv6OptionUnknownAction = 0 + + // IPv6OptionUnknownActionDiscard indicates that the packet must be silently + // discarded. + IPv6OptionUnknownActionDiscard IPv6OptionUnknownAction = 1 + + // IPv6OptionUnknownActionDiscardSendICMP indicates that the packet must be + // discarded and the node must send an ICMP Parameter Problem, Code 2, message + // to the packet's source, regardless of whether or not the packet's + // Destination was a multicast address. + IPv6OptionUnknownActionDiscardSendICMP IPv6OptionUnknownAction = 2 + + // IPv6OptionUnknownActionDiscardSendICMPNoMulticastDest indicates that the + // packet must be discarded and the node must send an ICMP Parameter Problem, + // Code 2, message to the packet's source only if the packet's Destination was + // not a multicast address. + IPv6OptionUnknownActionDiscardSendICMPNoMulticastDest IPv6OptionUnknownAction = 3 +) + +// IPv6ExtHdrOption is implemented by the various IPv6 extension header options. +type IPv6ExtHdrOption interface { + // UnknownAction returns the action to take in response to an unrecognized + // option. + UnknownAction() IPv6OptionUnknownAction + + // isIPv6ExtHdrOption is used to "lock" this interface so it is not + // implemented by other packages. + isIPv6ExtHdrOption() +} + +// IPv6ExtHdrOptionIndentifier is an IPv6 extension header option identifier. +type IPv6ExtHdrOptionIndentifier uint8 + +const ( + // ipv6Pad1ExtHdrOptionIdentifier is the identifier for a padding option that + // provides 1 byte padding, as outlined in RFC 8200 section 4.2. + ipv6Pad1ExtHdrOptionIdentifier IPv6ExtHdrOptionIndentifier = 0 + + // ipv6PadBExtHdrOptionIdentifier is the identifier for a padding option that + // provides variable length byte padding, as outlined in RFC 8200 section 4.2. + ipv6PadNExtHdrOptionIdentifier IPv6ExtHdrOptionIndentifier = 1 +) + +// IPv6UnknownExtHdrOption holds the identifier and data for an IPv6 extension +// header option that is unknown by the parsing utilities. +type IPv6UnknownExtHdrOption struct { + Identifier IPv6ExtHdrOptionIndentifier + Data []byte +} + +// UnknownAction implements IPv6OptionUnknownAction.UnknownAction. +func (o *IPv6UnknownExtHdrOption) UnknownAction() IPv6OptionUnknownAction { + return IPv6OptionUnknownAction((o.Identifier & ipv6UnknownExtHdrOptionActionMask) >> ipv6UnknownExtHdrOptionActionShift) +} + +// isIPv6ExtHdrOption implements IPv6ExtHdrOption.isIPv6ExtHdrOption. +func (*IPv6UnknownExtHdrOption) isIPv6ExtHdrOption() {} + +// Next returns the next option in the options data. +// +// If the next item is not a known extension header option, +// IPv6UnknownExtHdrOption will be returned with the option identifier and data. +// +// The return is of the format (option, done, error). done will be true when +// Next is unable to return anything because the iterator has reached the end of +// the options data, or an error occured. +func (i *IPv6OptionsExtHdrOptionsIterator) Next() (IPv6ExtHdrOption, bool, error) { + for { + temp, err := i.reader.ReadByte() + if err != nil { + // If we can't read the first byte of a new option, then we know the + // options buffer has been exhausted and we are done iterating. + return nil, true, nil + } + id := IPv6ExtHdrOptionIndentifier(temp) + + // If the option identifier indicates the option is a Pad1 option, then we + // know the option does not have Length and Data fields. End processing of + // the Pad1 option and continue processing the buffer as a new option. + if id == ipv6Pad1ExtHdrOptionIdentifier { + continue + } + + length, err := i.reader.ReadByte() + if err != nil { + if err != io.EOF { + // ReadByte should only ever return nil or io.EOF. + panic(fmt.Sprintf("unexpected error when reading the option's Length field for option with id = %d: %s", id, err)) + } + + // We use io.ErrUnexpectedEOF as exhausting the buffer is unexpected once + // we start parsing an option; we expect the reader to contain enough + // bytes for the whole option. + return nil, true, fmt.Errorf("error when reading the option's Length field for option with id = %d: %w", id, io.ErrUnexpectedEOF) + } + + // Special-case the variable length padding option to avoid a copy. + if id == ipv6PadNExtHdrOptionIdentifier { + // Do we have enough bytes in the reader for the PadN option? + if n := i.reader.Len(); n < int(length) { + // Reset the reader to effectively consume the remaining buffer. + i.reader.Reset(nil) + + // We return the same error as if we failed to read a non-padding option + // so consumers of this iterator don't need to differentiate between + // padding and non-padding options. + return nil, true, fmt.Errorf("read %d out of %d option data bytes for option with id = %d: %w", n, length, id, io.ErrUnexpectedEOF) + } + + if _, err := i.reader.Seek(int64(length), io.SeekCurrent); err != nil { + panic(fmt.Sprintf("error when skipping PadN (N = %d) option's data bytes: %s", length, err)) + } + + // End processing of the PadN option and continue processing the buffer as + // a new option. + continue + } + + bytes := make([]byte, length) + if n, err := io.ReadFull(&i.reader, bytes); err != nil { + // io.ReadFull may return io.EOF if i.reader has been exhausted. We use + // io.ErrUnexpectedEOF instead as the io.EOF is unexpected given the + // Length field found in the option. + if err == io.EOF { + err = io.ErrUnexpectedEOF + } + + return nil, true, fmt.Errorf("read %d out of %d option data bytes for option with id = %d: %w", n, length, id, err) + } + + return &IPv6UnknownExtHdrOption{Identifier: id, Data: bytes}, false, nil + } +} + +// IPv6HopByHopOptionsExtHdr is a buffer holding the Hop By Hop Options +// extension header. +type IPv6HopByHopOptionsExtHdr struct { + ipv6OptionsExtHdr +} + +// isIPv6PayloadHeader implements IPv6PayloadHeader.isIPv6PayloadHeader. +func (IPv6HopByHopOptionsExtHdr) isIPv6PayloadHeader() {} + +// IPv6DestinationOptionsExtHdr is a buffer holding the Destination Options +// extension header. +type IPv6DestinationOptionsExtHdr struct { + ipv6OptionsExtHdr +} + +// isIPv6PayloadHeader implements IPv6PayloadHeader.isIPv6PayloadHeader. +func (IPv6DestinationOptionsExtHdr) isIPv6PayloadHeader() {} + // IPv6RoutingExtHdr is a buffer holding the Routing extension header specific // data as outlined in RFC 8200 section 4.4. type IPv6RoutingExtHdr []byte @@ -176,45 +375,19 @@ type IPv6PayloadIterator struct { // MakeIPv6PayloadIterator returns an iterator over the IPv6 payload containing // extension headers, or a raw payload if the payload cannot be parsed. -func MakeIPv6PayloadIterator(nextHdrIdentifier IPv6ExtensionHeaderIdentifier, payload buffer.VectorisedView, check bool) (IPv6PayloadIterator, error) { +func MakeIPv6PayloadIterator(nextHdrIdentifier IPv6ExtensionHeaderIdentifier, payload buffer.VectorisedView) IPv6PayloadIterator { readers := payload.Readers() readerPs := make([]io.Reader, 0, len(readers)) for i := range readers { readerPs = append(readerPs, &readers[i]) } - // We need a buffer of size 1 for calls to bufio.Reader.ReadByte. - reader := *bufio.NewReaderSize(io.MultiReader(readerPs...), 1) - - it := IPv6PayloadIterator{ + return IPv6PayloadIterator{ nextHdrIdentifier: nextHdrIdentifier, payload: payload.Clone(nil), - reader: reader, - } - - var err error - - if check { - for { - var done bool - if _, done, err = it.Next(); err != nil || done { - break - } - } - - // Reset it (and its underlying readers) before returning it. - for i := range readers { - readers[i].Seek(0, io.SeekStart) - } - reader.Reset(io.MultiReader(readerPs...)) - it = IPv6PayloadIterator{ - nextHdrIdentifier: nextHdrIdentifier, - payload: payload.Clone(nil), - reader: reader, - } + // We need a buffer of size 1 for calls to bufio.Reader.ReadByte. + reader: *bufio.NewReaderSize(io.MultiReader(readerPs...), 1), } - - return it, err } // AsRawHeader returns the remaining payload of i as a raw header and @@ -252,6 +425,14 @@ func (i *IPv6PayloadIterator) Next() (IPv6PayloadHeader, bool, error) { // Is the header we are parsing a known extension header? switch i.nextHdrIdentifier { + case IPv6HopByHopOptionsExtHdrIdentifier: + nextHdrIdentifier, bytes, err := i.nextHeaderData(false /* fragmentHdr */, nil) + if err != nil { + return nil, true, err + } + + i.nextHdrIdentifier = nextHdrIdentifier + return IPv6HopByHopOptionsExtHdr{ipv6OptionsExtHdr: bytes}, false, nil case IPv6RoutingExtHdrIdentifier: nextHdrIdentifier, bytes, err := i.nextHeaderData(false /* fragmentHdr */, nil) if err != nil { @@ -280,6 +461,14 @@ func (i *IPv6PayloadIterator) Next() (IPv6PayloadHeader, bool, error) { i.nextHdrIdentifier = nextHdrIdentifier return fragmentExtHdr, false, nil + case IPv6DestinationOptionsExtHdrIdentifier: + nextHdrIdentifier, bytes, err := i.nextHeaderData(false /* fragmentHdr */, nil) + if err != nil { + return nil, true, err + } + + i.nextHdrIdentifier = nextHdrIdentifier + return IPv6DestinationOptionsExtHdr{ipv6OptionsExtHdr: bytes}, false, nil case IPv6NoNextHeaderIdentifier: // This indicates the end of the IPv6 payload. return nil, true, nil @@ -315,13 +504,11 @@ func (i *IPv6PayloadIterator) nextHeaderData(fragmentHdr bool, bytes []byte) (IP length, err = i.reader.ReadByte() i.payload.TrimFront(1) if err != nil { - var ret error if fragmentHdr { - ret = fmt.Errorf("error when reading the Length field for extension header with id = %d: %w", i.nextHdrIdentifier, err) - } else { - ret = fmt.Errorf("error when reading the Reserved field for extension header with id = %d: %w", i.nextHdrIdentifier, err) + return 0, nil, fmt.Errorf("error when reading the Length field for extension header with id = %d: %w", i.nextHdrIdentifier, err) } - return 0, nil, ret + + return 0, nil, fmt.Errorf("error when reading the Reserved field for extension header with id = %d: %w", i.nextHdrIdentifier, err) } if fragmentHdr { length = 0 diff --git a/pkg/tcpip/header/ipv6_extension_headers_test.go b/pkg/tcpip/header/ipv6_extension_headers_test.go index 4bfdc77c4..133ccc8b6 100644 --- a/pkg/tcpip/header/ipv6_extension_headers_test.go +++ b/pkg/tcpip/header/ipv6_extension_headers_test.go @@ -36,6 +36,354 @@ func (a IPv6RawPayloadHeader) Equal(b IPv6RawPayloadHeader) bool { return a.Identifier == b.Identifier && bytes.Equal(a.Buf.ToView(), b.Buf.ToView()) } +// Equal returns true of a and b are equivalent. +// +// Note, Equal will return true if a and b hold equivalent ipv6OptionsExtHdrs. +// +// Needed to use cmp.Equal on IPv6RawPayloadHeader as it contains unexported +// fields. +func (a IPv6HopByHopOptionsExtHdr) Equal(b IPv6HopByHopOptionsExtHdr) bool { + return bytes.Equal(a.ipv6OptionsExtHdr, b.ipv6OptionsExtHdr) +} + +// Equal returns true of a and b are equivalent. +// +// Note, Equal will return true if a and b hold equivalent ipv6OptionsExtHdrs. +// +// Needed to use cmp.Equal on IPv6RawPayloadHeader as it contains unexported +// fields. +func (a IPv6DestinationOptionsExtHdr) Equal(b IPv6DestinationOptionsExtHdr) bool { + return bytes.Equal(a.ipv6OptionsExtHdr, b.ipv6OptionsExtHdr) +} + +func TestIPv6UnknownExtHdrOption(t *testing.T) { + tests := []struct { + name string + identifier IPv6ExtHdrOptionIndentifier + expectedUnknownAction IPv6OptionUnknownAction + }{ + { + name: "Skip with zero LSBs", + identifier: 0, + expectedUnknownAction: IPv6OptionUnknownActionSkip, + }, + { + name: "Discard with zero LSBs", + identifier: 64, + expectedUnknownAction: IPv6OptionUnknownActionDiscard, + }, + { + name: "Discard and ICMP with zero LSBs", + identifier: 128, + expectedUnknownAction: IPv6OptionUnknownActionDiscardSendICMP, + }, + { + name: "Discard and ICMP for non multicast destination with zero LSBs", + identifier: 192, + expectedUnknownAction: IPv6OptionUnknownActionDiscardSendICMPNoMulticastDest, + }, + { + name: "Skip with non-zero LSBs", + identifier: 63, + expectedUnknownAction: IPv6OptionUnknownActionSkip, + }, + { + name: "Discard with non-zero LSBs", + identifier: 127, + expectedUnknownAction: IPv6OptionUnknownActionDiscard, + }, + { + name: "Discard and ICMP with non-zero LSBs", + identifier: 191, + expectedUnknownAction: IPv6OptionUnknownActionDiscardSendICMP, + }, + { + name: "Discard and ICMP for non multicast destination with non-zero LSBs", + identifier: 255, + expectedUnknownAction: IPv6OptionUnknownActionDiscardSendICMPNoMulticastDest, + }, + } + + for _, test := range tests { + t.Run(test.name, func(t *testing.T) { + opt := &IPv6UnknownExtHdrOption{Identifier: test.identifier, Data: []byte{1, 2, 3, 4}} + if a := opt.UnknownAction(); a != test.expectedUnknownAction { + t.Fatalf("got UnknownAction() = %d, want = %d", a, test.expectedUnknownAction) + } + }) + } + +} + +func TestIPv6OptionsExtHdrIterErr(t *testing.T) { + tests := []struct { + name string + bytes []byte + err error + }{ + { + name: "Single unknown with zero length", + bytes: []byte{255, 0}, + }, + { + name: "Single unknown with non-zero length", + bytes: []byte{255, 3, 1, 2, 3}, + }, + { + name: "Two options", + bytes: []byte{ + 255, 0, + 254, 1, 1, + }, + }, + { + name: "Three options", + bytes: []byte{ + 255, 0, + 254, 1, 1, + 253, 4, 2, 3, 4, 5, + }, + }, + { + name: "Single unknown only identifier", + bytes: []byte{255}, + err: io.ErrUnexpectedEOF, + }, + { + name: "Single unknown too small with length = 1", + bytes: []byte{255, 1}, + err: io.ErrUnexpectedEOF, + }, + { + name: "Single unknown too small with length = 2", + bytes: []byte{255, 2, 1}, + err: io.ErrUnexpectedEOF, + }, + { + name: "Valid first with second unknown only identifier", + bytes: []byte{ + 255, 0, + 254, + }, + err: io.ErrUnexpectedEOF, + }, + { + name: "Valid first with second unknown missing data", + bytes: []byte{ + 255, 0, + 254, 1, + }, + err: io.ErrUnexpectedEOF, + }, + { + name: "Valid first with second unknown too small", + bytes: []byte{ + 255, 0, + 254, 2, 1, + }, + err: io.ErrUnexpectedEOF, + }, + { + name: "One Pad1", + bytes: []byte{0}, + }, + { + name: "Multiple Pad1", + bytes: []byte{0, 0, 0}, + }, + { + name: "Multiple PadN", + bytes: []byte{ + // Pad3 + 1, 1, 1, + + // Pad5 + 1, 3, 1, 2, 3, + }, + }, + { + name: "Pad5 too small middle of data buffer", + bytes: []byte{1, 3, 1, 2}, + err: io.ErrUnexpectedEOF, + }, + { + name: "Pad5 no data", + bytes: []byte{1, 3}, + err: io.ErrUnexpectedEOF, + }, + } + + check := func(t *testing.T, it IPv6OptionsExtHdrOptionsIterator, expectedErr error) { + for i := 0; ; i++ { + _, done, err := it.Next() + if err != nil { + // If we encountered a non-nil error while iterating, make sure it is + // is the same error as expectedErr. + if !errors.Is(err, expectedErr) { + t.Fatalf("got %d-th Next() = %v, want = %v", i, err, expectedErr) + } + + return + } + if done { + // If we are done (without an error), make sure that we did not expect + // an error. + if expectedErr != nil { + t.Fatalf("expected error when iterating; want = %s", expectedErr) + } + + return + } + } + } + + for _, test := range tests { + t.Run(test.name, func(t *testing.T) { + t.Run("Hop By Hop", func(t *testing.T) { + extHdr := IPv6HopByHopOptionsExtHdr{ipv6OptionsExtHdr: test.bytes} + check(t, extHdr.Iter(), test.err) + }) + + t.Run("Destination", func(t *testing.T) { + extHdr := IPv6DestinationOptionsExtHdr{ipv6OptionsExtHdr: test.bytes} + check(t, extHdr.Iter(), test.err) + }) + }) + } +} + +func TestIPv6OptionsExtHdrIter(t *testing.T) { + tests := []struct { + name string + bytes []byte + expected []IPv6ExtHdrOption + }{ + { + name: "Single unknown with zero length", + bytes: []byte{255, 0}, + expected: []IPv6ExtHdrOption{ + &IPv6UnknownExtHdrOption{Identifier: 255, Data: []byte{}}, + }, + }, + { + name: "Single unknown with non-zero length", + bytes: []byte{255, 3, 1, 2, 3}, + expected: []IPv6ExtHdrOption{ + &IPv6UnknownExtHdrOption{Identifier: 255, Data: []byte{1, 2, 3}}, + }, + }, + { + name: "Single Pad1", + bytes: []byte{0}, + }, + { + name: "Two Pad1", + bytes: []byte{0, 0}, + }, + { + name: "Single Pad3", + bytes: []byte{1, 1, 1}, + }, + { + name: "Single Pad5", + bytes: []byte{1, 3, 1, 2, 3}, + }, + { + name: "Multiple Pad", + bytes: []byte{ + // Pad1 + 0, + + // Pad2 + 1, 0, + + // Pad3 + 1, 1, 1, + + // Pad4 + 1, 2, 1, 2, + + // Pad5 + 1, 3, 1, 2, 3, + }, + }, + { + name: "Multiple options", + bytes: []byte{ + // Pad1 + 0, + + // Unknown + 255, 0, + + // Pad2 + 1, 0, + + // Unknown + 254, 1, 1, + + // Pad3 + 1, 1, 1, + + // Unknown + 253, 4, 2, 3, 4, 5, + + // Pad4 + 1, 2, 1, 2, + }, + expected: []IPv6ExtHdrOption{ + &IPv6UnknownExtHdrOption{Identifier: 255, Data: []byte{}}, + &IPv6UnknownExtHdrOption{Identifier: 254, Data: []byte{1}}, + &IPv6UnknownExtHdrOption{Identifier: 253, Data: []byte{2, 3, 4, 5}}, + }, + }, + } + + checkIter := func(t *testing.T, it IPv6OptionsExtHdrOptionsIterator, expected []IPv6ExtHdrOption) { + for i, e := range expected { + opt, done, err := it.Next() + if err != nil { + t.Errorf("(i=%d) Next(): %s", i, err) + } + if done { + t.Errorf("(i=%d) unexpectedly done iterating", i) + } + if diff := cmp.Diff(e, opt); diff != "" { + t.Errorf("(i=%d) got option mismatch (-want +got):\n%s", i, diff) + } + + if t.Failed() { + t.FailNow() + } + } + + opt, done, err := it.Next() + if err != nil { + t.Errorf("(last) Next(): %s", err) + } + if !done { + t.Errorf("(last) iterator unexpectedly not done") + } + if opt != nil { + t.Errorf("(last) got Next() = %T, want = nil", opt) + } + } + + for _, test := range tests { + t.Run(test.name, func(t *testing.T) { + t.Run("Hop By Hop", func(t *testing.T) { + extHdr := IPv6HopByHopOptionsExtHdr{ipv6OptionsExtHdr: test.bytes} + checkIter(t, extHdr.Iter(), test.expected) + }) + + t.Run("Destination", func(t *testing.T) { + extHdr := IPv6DestinationOptionsExtHdr{ipv6OptionsExtHdr: test.bytes} + checkIter(t, extHdr.Iter(), test.expected) + }) + }) + } +} + func TestIPv6RoutingExtHdr(t *testing.T) { tests := []struct { name string @@ -144,7 +492,6 @@ func TestIPv6ExtHdrIterErr(t *testing.T) { firstNextHdr: 255, payload: makeVectorisedViewFromByteBuffers([]byte{1, 2, 3, 4}), }, - { name: "No next header", firstNextHdr: IPv6NoNextHeaderIdentifier, @@ -154,7 +501,17 @@ func TestIPv6ExtHdrIterErr(t *testing.T) { firstNextHdr: IPv6NoNextHeaderIdentifier, payload: makeVectorisedViewFromByteBuffers([]byte{1, 2, 3, 4}), }, - + { + name: "Valid single hop by hop", + firstNextHdr: IPv6HopByHopOptionsExtHdrIdentifier, + payload: makeVectorisedViewFromByteBuffers([]byte{255, 0, 1, 4, 1, 2, 3, 4}), + }, + { + name: "Hop by hop too small", + firstNextHdr: IPv6HopByHopOptionsExtHdrIdentifier, + payload: makeVectorisedViewFromByteBuffers([]byte{255, 0, 1, 4, 1, 2, 3}), + err: io.ErrUnexpectedEOF, + }, { name: "Valid single fragment", firstNextHdr: IPv6FragmentExtHdrIdentifier, @@ -166,7 +523,17 @@ func TestIPv6ExtHdrIterErr(t *testing.T) { payload: makeVectorisedViewFromByteBuffers([]byte{255, 0, 68, 9, 128, 4, 2}), err: io.ErrUnexpectedEOF, }, - + { + name: "Valid single destination", + firstNextHdr: IPv6DestinationOptionsExtHdrIdentifier, + payload: makeVectorisedViewFromByteBuffers([]byte{255, 0, 1, 4, 1, 2, 3, 4}), + }, + { + name: "Destination too small", + firstNextHdr: IPv6DestinationOptionsExtHdrIdentifier, + payload: makeVectorisedViewFromByteBuffers([]byte{255, 0, 1, 4, 1, 2, 3}), + err: io.ErrUnexpectedEOF, + }, { name: "Valid single routing", firstNextHdr: IPv6RoutingExtHdrIdentifier, @@ -205,31 +572,93 @@ func TestIPv6ExtHdrIterErr(t *testing.T) { payload: makeVectorisedViewFromByteBuffers([]byte{255, 1, 1, 2, 3, 4, 5, 6}, []byte{1, 2, 3, 4, 5, 6, 7}), err: io.ErrUnexpectedEOF, }, - { name: "Mixed", - firstNextHdr: IPv6FragmentExtHdrIdentifier, + firstNextHdr: IPv6HopByHopOptionsExtHdrIdentifier, payload: makeVectorisedViewFromByteBuffers([]byte{ - // Fragment extension header. - uint8(IPv6RoutingExtHdrIdentifier), 0, 68, 9, 128, 4, 2, 1, + // Hop By Hop Options extension header. + uint8(IPv6FragmentExtHdrIdentifier), 0, 1, 4, 1, 2, 3, 4, + + // (Atomic) Fragment extension header. + // + // Reserved bits are 1 which should not affect anything. + uint8(IPv6RoutingExtHdrIdentifier), 255, 0, 6, 128, 4, 2, 1, // Routing extension header. - 255, 0, 1, 2, 3, 4, 5, 6, + uint8(IPv6DestinationOptionsExtHdrIdentifier), 0, 1, 2, 3, 4, 5, 6, + + // Destination Options extension header. + 255, 0, 255, 4, 1, 2, 3, 4, // Upper layer data. 1, 2, 3, 4, }), }, + { + name: "Mixed without upper layer data", + firstNextHdr: IPv6HopByHopOptionsExtHdrIdentifier, + payload: makeVectorisedViewFromByteBuffers([]byte{ + // Hop By Hop Options extension header. + uint8(IPv6FragmentExtHdrIdentifier), 0, 1, 4, 1, 2, 3, 4, + + // (Atomic) Fragment extension header. + // + // Reserved bits are 1 which should not affect anything. + uint8(IPv6RoutingExtHdrIdentifier), 255, 0, 6, 128, 4, 2, 1, + + // Routing extension header. + uint8(IPv6DestinationOptionsExtHdrIdentifier), 0, 1, 2, 3, 4, 5, 6, + + // Destination Options extension header. + 255, 0, 255, 4, 1, 2, 3, 4, + }), + }, + { + name: "Mixed without upper layer data but last ext hdr too small", + firstNextHdr: IPv6HopByHopOptionsExtHdrIdentifier, + payload: makeVectorisedViewFromByteBuffers([]byte{ + // Hop By Hop Options extension header. + uint8(IPv6FragmentExtHdrIdentifier), 0, 1, 4, 1, 2, 3, 4, + + // (Atomic) Fragment extension header. + // + // Reserved bits are 1 which should not affect anything. + uint8(IPv6RoutingExtHdrIdentifier), 255, 0, 6, 128, 4, 2, 1, + + // Routing extension header. + uint8(IPv6DestinationOptionsExtHdrIdentifier), 0, 1, 2, 3, 4, 5, 6, + + // Destination Options extension header. + 255, 0, 255, 4, 1, 2, 3, + }), + err: io.ErrUnexpectedEOF, + }, } for _, test := range tests { t.Run(test.name, func(t *testing.T) { - if _, err := MakeIPv6PayloadIterator(test.firstNextHdr, test.payload, false); err != nil { - t.Errorf("got MakeIPv6PayloadIterator(%d, _, false) = %s, want = nil", test.firstNextHdr, err) - } + it := MakeIPv6PayloadIterator(test.firstNextHdr, test.payload) + + for i := 0; ; i++ { + _, done, err := it.Next() + if err != nil { + // If we encountered a non-nil error while iterating, make sure it is + // is the same error as test.err. + if !errors.Is(err, test.err) { + t.Fatalf("got %d-th Next() = %v, want = %v", i, err, test.err) + } + + return + } + if done { + // If we are done (without an error), make sure that we did not expect + // an error. + if test.err != nil { + t.Fatalf("expected error when iterating; want = %s", test.err) + } - if _, err := MakeIPv6PayloadIterator(test.firstNextHdr, test.payload, true); !errors.Is(err, test.err) { - t.Errorf("got MakeIPv6PayloadIterator(%d, _, true) = %v, want = %v", test.firstNextHdr, err, test.err) + return + } } }) } @@ -247,9 +676,12 @@ func TestIPv6ExtHdrIter(t *testing.T) { // With a non-atomic fragment, the payload after the fragment will not be // parsed because the payload may not be complete. { - name: "fragment - routing - upper", - firstNextHdr: IPv6FragmentExtHdrIdentifier, + name: "hopbyhop - fragment - routing - upper", + firstNextHdr: IPv6HopByHopOptionsExtHdrIdentifier, payload: makeVectorisedViewFromByteBuffers([]byte{ + // Hop By Hop extension header. + uint8(IPv6FragmentExtHdrIdentifier), 0, 1, 4, 1, 2, 3, 4, + // Fragment extension header. uint8(IPv6RoutingExtHdrIdentifier), 0, 68, 9, 128, 4, 2, 1, @@ -260,6 +692,7 @@ func TestIPv6ExtHdrIter(t *testing.T) { 1, 2, 3, 4, }), expected: []IPv6PayloadHeader{ + IPv6HopByHopOptionsExtHdr{ipv6OptionsExtHdr: []byte{1, 4, 1, 2, 3, 4}}, IPv6FragmentExtHdr([6]byte{68, 9, 128, 4, 2, 1}), IPv6RawPayloadHeader{ Identifier: IPv6RoutingExtHdrIdentifier, @@ -292,7 +725,7 @@ func TestIPv6ExtHdrIter(t *testing.T) { // If we have an atomic fragment, the payload following the fragment // extension header should be parsed normally. { - name: "atomic fragment - routing - upper", + name: "atomic fragment - routing - destination - upper", firstNextHdr: IPv6FragmentExtHdrIdentifier, payload: makeVectorisedViewFromByteBuffers([]byte{ // Fragment extension header. @@ -301,7 +734,10 @@ func TestIPv6ExtHdrIter(t *testing.T) { uint8(IPv6RoutingExtHdrIdentifier), 255, 0, 6, 128, 4, 2, 1, // Routing extension header. - 255, 0, 1, 2, 3, 4, 5, 6, + uint8(IPv6DestinationOptionsExtHdrIdentifier), 0, 1, 2, 3, 4, 5, 6, + + // Destination Options extension header. + 255, 0, 1, 4, 1, 2, 3, 4, // Upper layer data. 1, 2, 3, 4, @@ -309,6 +745,7 @@ func TestIPv6ExtHdrIter(t *testing.T) { expected: []IPv6PayloadHeader{ IPv6FragmentExtHdr([6]byte{0, 6, 128, 4, 2, 1}), IPv6RoutingExtHdr([]byte{1, 2, 3, 4, 5, 6}), + IPv6DestinationOptionsExtHdr{ipv6OptionsExtHdr: []byte{1, 4, 1, 2, 3, 4}}, IPv6RawPayloadHeader{ Identifier: 255, Buf: upperLayerData.ToVectorisedView(), @@ -339,19 +776,23 @@ func TestIPv6ExtHdrIter(t *testing.T) { }, }, { - name: "atomic fragment - no next header", + name: "atomic fragment - destination - no next header", firstNextHdr: IPv6FragmentExtHdrIdentifier, payload: makeVectorisedViewFromByteBuffers([]byte{ // Fragment extension header. // // Res (Reserved) bits are 1 which should not affect anything. - uint8(IPv6NoNextHeaderIdentifier), 0, 0, 6, 128, 4, 2, 1, + uint8(IPv6DestinationOptionsExtHdrIdentifier), 0, 0, 6, 128, 4, 2, 1, + + // Destination Options extension header. + uint8(IPv6NoNextHeaderIdentifier), 0, 1, 4, 1, 2, 3, 4, // Random data. 1, 2, 3, 4, }), expected: []IPv6PayloadHeader{ IPv6FragmentExtHdr([6]byte{0, 6, 128, 4, 2, 1}), + IPv6DestinationOptionsExtHdr{ipv6OptionsExtHdr: []byte{1, 4, 1, 2, 3, 4}}, }, }, { @@ -395,9 +836,12 @@ func TestIPv6ExtHdrIter(t *testing.T) { }, }, { - name: "routing - fragment - no next header", - firstNextHdr: IPv6RoutingExtHdrIdentifier, + name: "hopbyhop - routing - fragment - no next header", + firstNextHdr: IPv6HopByHopOptionsExtHdrIdentifier, payload: makeVectorisedViewFromByteBuffers([]byte{ + // Hop By Hop Options extension header. + uint8(IPv6RoutingExtHdrIdentifier), 0, 1, 4, 1, 2, 3, 4, + // Routing extension header. uint8(IPv6FragmentExtHdrIdentifier), 0, 1, 2, 3, 4, 5, 6, @@ -410,6 +854,7 @@ func TestIPv6ExtHdrIter(t *testing.T) { 1, 2, 3, 4, }), expected: []IPv6PayloadHeader{ + IPv6HopByHopOptionsExtHdr{ipv6OptionsExtHdr: []byte{1, 4, 1, 2, 3, 4}}, IPv6RoutingExtHdr([]byte{1, 2, 3, 4, 5, 6}), IPv6FragmentExtHdr([6]byte{1, 6, 128, 4, 2, 1}), IPv6RawPayloadHeader{ @@ -478,10 +923,7 @@ func TestIPv6ExtHdrIter(t *testing.T) { for _, test := range tests { t.Run(test.name, func(t *testing.T) { - it, err := MakeIPv6PayloadIterator(test.firstNextHdr, test.payload, true) - if err != nil { - t.Fatalf("MakeIPv6PayloadIterator(%d, _ true): %s", test.firstNextHdr, err) - } + it := MakeIPv6PayloadIterator(test.firstNextHdr, test.payload) for i, e := range test.expected { extHdr, done, err := it.Next() diff --git a/pkg/tcpip/network/ipv6/ipv6.go b/pkg/tcpip/network/ipv6/ipv6.go index a703a768c..685239017 100644 --- a/pkg/tcpip/network/ipv6/ipv6.go +++ b/pkg/tcpip/network/ipv6/ipv6.go @@ -184,24 +184,61 @@ func (e *endpoint) HandlePacket(r *stack.Route, pkt stack.PacketBuffer) { pkt.Data.TrimFront(header.IPv6MinimumSize) pkt.Data.CapLength(int(h.PayloadLength())) - it, err := header.MakeIPv6PayloadIterator(header.IPv6ExtensionHeaderIdentifier(h.NextHeader()), pkt.Data, true) - if err != nil { - r.Stats().IP.MalformedPacketsReceived.Increment() - return - } + it := header.MakeIPv6PayloadIterator(header.IPv6ExtensionHeaderIdentifier(h.NextHeader()), pkt.Data) - for { + for firstHeader := true; ; firstHeader = false { extHdr, done, err := it.Next() if err != nil { - // This should never happen as MakeIPv6PayloadIterator above did not - // return an error. - panic(fmt.Sprintf("unexpected error when iterating over IPv6 payload: %s", err)) + r.Stats().IP.MalformedPacketsReceived.Increment() + return } if done { break } switch extHdr := extHdr.(type) { + case header.IPv6HopByHopOptionsExtHdr: + // As per RFC 8200 section 4.1, the Hop By Hop extension header is + // restricted to appear immediately after an IPv6 fixed header. + // + // TODO(b/152019344): Send an ICMPv6 Parameter Problem, Code 1 + // (unrecognized next header) error in response to an extension header's + // Next Header field with the Hop By Hop extension header identifier. + if !firstHeader { + return + } + + optsIt := extHdr.Iter() + + for { + opt, done, err := optsIt.Next() + if err != nil { + r.Stats().IP.MalformedPacketsReceived.Increment() + return + } + if done { + break + } + + // We currently do not support any IPv6 Hop By Hop extension header + // options. + switch opt.UnknownAction() { + case header.IPv6OptionUnknownActionSkip: + case header.IPv6OptionUnknownActionDiscard: + return + case header.IPv6OptionUnknownActionDiscardSendICMP: + // TODO(b/152019344): Send an ICMPv6 Parameter Problem Code 2 for + // unrecognized IPv6 extension header options. + return + case header.IPv6OptionUnknownActionDiscardSendICMPNoMulticastDest: + // TODO(b/152019344): Send an ICMPv6 Parameter Problem Code 2 for + // unrecognized IPv6 extension header options. + return + default: + panic(fmt.Sprintf("unrecognized action for an unrecognized Hop By Hop extension header option = %d", opt)) + } + } + case header.IPv6RoutingExtHdr: // As per RFC 8200 section 4.4, if a node encounters a routing header with // an unrecognized routing type value, with a non-zero Segments Left @@ -266,12 +303,39 @@ func (e *endpoint) HandlePacket(r *stack.Route, pkt stack.PacketBuffer) { // We create a new iterator with the reassembled packet because we could // have more extension headers in the reassembled payload, as per RFC // 8200 section 4.5. - it, err = header.MakeIPv6PayloadIterator(rawPayload.Identifier, pkt.Data, true) + it = header.MakeIPv6PayloadIterator(rawPayload.Identifier, pkt.Data) + } + + case header.IPv6DestinationOptionsExtHdr: + optsIt := extHdr.Iter() + + for { + opt, done, err := optsIt.Next() if err != nil { r.Stats().IP.MalformedPacketsReceived.Increment() - r.Stats().IP.MalformedFragmentsReceived.Increment() return } + if done { + break + } + + // We currently do not support any IPv6 Destination extension header + // options. + switch opt.UnknownAction() { + case header.IPv6OptionUnknownActionSkip: + case header.IPv6OptionUnknownActionDiscard: + return + case header.IPv6OptionUnknownActionDiscardSendICMP: + // TODO(b/152019344): Send an ICMPv6 Parameter Problem Code 2 for + // unrecognized IPv6 extension header options. + return + case header.IPv6OptionUnknownActionDiscardSendICMPNoMulticastDest: + // TODO(b/152019344): Send an ICMPv6 Parameter Problem Code 2 for + // unrecognized IPv6 extension header options. + return + default: + panic(fmt.Sprintf("unrecognized action for an unrecognized Destination extension header option = %d", opt)) + } } case header.IPv6RawPayloadHeader: diff --git a/pkg/tcpip/network/ipv6/ipv6_test.go b/pkg/tcpip/network/ipv6/ipv6_test.go index 86bfda85e..37f7e53ce 100644 --- a/pkg/tcpip/network/ipv6/ipv6_test.go +++ b/pkg/tcpip/network/ipv6/ipv6_test.go @@ -37,9 +37,11 @@ const ( // Tests use the extension header identifier values as uint8 instead of // header.IPv6ExtensionHeaderIdentifier. - routingExtHdrID = uint8(header.IPv6RoutingExtHdrIdentifier) - fragmentExtHdrID = uint8(header.IPv6FragmentExtHdrIdentifier) - noNextHdrID = uint8(header.IPv6NoNextHeaderIdentifier) + hopByHopExtHdrID = uint8(header.IPv6HopByHopOptionsExtHdrIdentifier) + routingExtHdrID = uint8(header.IPv6RoutingExtHdrIdentifier) + fragmentExtHdrID = uint8(header.IPv6FragmentExtHdrIdentifier) + destinationExtHdrID = uint8(header.IPv6DestinationOptionsExtHdrIdentifier) + noNextHdrID = uint8(header.IPv6NoNextHeaderIdentifier) ) // testReceiveICMP tests receiving an ICMP packet from src to dst. want is the @@ -290,6 +292,67 @@ func TestReceiveIPv6ExtHdrs(t *testing.T) { shouldAccept: true, }, { + name: "hopbyhop with unknown option skippable action", + extHdr: func(nextHdr uint8) ([]byte, uint8) { + return []byte{ + nextHdr, 1, + + // Skippable unknown. + 63, 4, 1, 2, 3, 4, + + // Skippable unknown. + 62, 6, 1, 2, 3, 4, 5, 6, + }, hopByHopExtHdrID + }, + shouldAccept: true, + }, + { + name: "hopbyhop with unknown option discard action", + extHdr: func(nextHdr uint8) ([]byte, uint8) { + return []byte{ + nextHdr, 1, + + // Skippable unknown. + 63, 4, 1, 2, 3, 4, + + // Discard unknown. + 127, 6, 1, 2, 3, 4, 5, 6, + }, hopByHopExtHdrID + }, + shouldAccept: false, + }, + { + name: "hopbyhop with unknown option discard and send icmp action", + extHdr: func(nextHdr uint8) ([]byte, uint8) { + return []byte{ + nextHdr, 1, + + // Skippable unknown. + 63, 4, 1, 2, 3, 4, + + // Discard & send ICMP if option is unknown. + 191, 6, 1, 2, 3, 4, 5, 6, + }, hopByHopExtHdrID + }, + shouldAccept: false, + }, + { + name: "hopbyhop with unknown option discard and send icmp action unless multicast dest", + extHdr: func(nextHdr uint8) ([]byte, uint8) { + return []byte{ + nextHdr, 1, + + // Skippable unknown. + 63, 4, 1, 2, 3, 4, + + // Discard & send ICMP unless packet is for multicast destination if + // option is unknown. + 255, 6, 1, 2, 3, 4, 5, 6, + }, hopByHopExtHdrID + }, + shouldAccept: false, + }, + { name: "routing with zero segments left", extHdr: func(nextHdr uint8) ([]byte, uint8) { return []byte{nextHdr, 0, 1, 0, 2, 3, 4, 5}, routingExtHdrID }, shouldAccept: true, @@ -315,6 +378,72 @@ func TestReceiveIPv6ExtHdrs(t *testing.T) { shouldAccept: false, }, { + name: "No next header", + extHdr: func(nextHdr uint8) ([]byte, uint8) { return []byte{}, noNextHdrID }, + shouldAccept: false, + }, + { + name: "destination with unknown option skippable action", + extHdr: func(nextHdr uint8) ([]byte, uint8) { + return []byte{ + nextHdr, 1, + + // Skippable unknown. + 63, 4, 1, 2, 3, 4, + + // Skippable unknown. + 62, 6, 1, 2, 3, 4, 5, 6, + }, destinationExtHdrID + }, + shouldAccept: true, + }, + { + name: "destination with unknown option discard action", + extHdr: func(nextHdr uint8) ([]byte, uint8) { + return []byte{ + nextHdr, 1, + + // Skippable unknown. + 63, 4, 1, 2, 3, 4, + + // Discard unknown. + 127, 6, 1, 2, 3, 4, 5, 6, + }, destinationExtHdrID + }, + shouldAccept: false, + }, + { + name: "destination with unknown option discard and send icmp action", + extHdr: func(nextHdr uint8) ([]byte, uint8) { + return []byte{ + nextHdr, 1, + + // Skippable unknown. + 63, 4, 1, 2, 3, 4, + + // Discard & send ICMP if option is unknown. + 191, 6, 1, 2, 3, 4, 5, 6, + }, destinationExtHdrID + }, + shouldAccept: false, + }, + { + name: "destination with unknown option discard and send icmp action unless multicast dest", + extHdr: func(nextHdr uint8) ([]byte, uint8) { + return []byte{ + nextHdr, 1, + + // Skippable unknown. + 63, 4, 1, 2, 3, 4, + + // Discard & send ICMP unless packet is for multicast destination if + // option is unknown. + 255, 6, 1, 2, 3, 4, 5, 6, + }, destinationExtHdrID + }, + shouldAccept: false, + }, + { name: "routing - atomic fragment", extHdr: func(nextHdr uint8) ([]byte, uint8) { return []byte{ @@ -341,10 +470,94 @@ func TestReceiveIPv6ExtHdrs(t *testing.T) { shouldAccept: true, }, { + name: "hop by hop (with skippable unknown) - routing", + extHdr: func(nextHdr uint8) ([]byte, uint8) { + return []byte{ + // Hop By Hop extension header with skippable unknown option. + routingExtHdrID, 0, 62, 4, 1, 2, 3, 4, + + // Routing extension header. + nextHdr, 0, 1, 0, 2, 3, 4, 5, + }, hopByHopExtHdrID + }, + shouldAccept: true, + }, + { + name: "routing - hop by hop (with skippable unknown)", + extHdr: func(nextHdr uint8) ([]byte, uint8) { + return []byte{ + // Routing extension header. + hopByHopExtHdrID, 0, 1, 0, 2, 3, 4, 5, + + // Hop By Hop extension header with skippable unknown option. + nextHdr, 0, 62, 4, 1, 2, 3, 4, + }, routingExtHdrID + }, + shouldAccept: false, + }, + { name: "No next header", extHdr: func(nextHdr uint8) ([]byte, uint8) { return []byte{}, noNextHdrID }, shouldAccept: false, }, + { + name: "hopbyhop (with skippable unknown) - routing - atomic fragment - destination (with skippable unknown)", + extHdr: func(nextHdr uint8) ([]byte, uint8) { + return []byte{ + // Hop By Hop extension header with skippable unknown option. + routingExtHdrID, 0, 62, 4, 1, 2, 3, 4, + + // Routing extension header. + fragmentExtHdrID, 0, 1, 0, 2, 3, 4, 5, + + // Fragment extension header. + destinationExtHdrID, 0, 0, 0, 1, 2, 3, 4, + + // Destination extension header with skippable unknown option. + nextHdr, 0, 63, 4, 1, 2, 3, 4, + }, hopByHopExtHdrID + }, + shouldAccept: true, + }, + { + name: "hopbyhop (with discard unknown) - routing - atomic fragment - destination (with skippable unknown)", + extHdr: func(nextHdr uint8) ([]byte, uint8) { + return []byte{ + // Hop By Hop extension header with discard action for unknown option. + routingExtHdrID, 0, 65, 4, 1, 2, 3, 4, + + // Routing extension header. + fragmentExtHdrID, 0, 1, 0, 2, 3, 4, 5, + + // Fragment extension header. + destinationExtHdrID, 0, 0, 0, 1, 2, 3, 4, + + // Destination extension header with skippable unknown option. + nextHdr, 0, 63, 4, 1, 2, 3, 4, + }, hopByHopExtHdrID + }, + shouldAccept: false, + }, + { + name: "hopbyhop (with skippable unknown) - routing - atomic fragment - destination (with discard unknown)", + extHdr: func(nextHdr uint8) ([]byte, uint8) { + return []byte{ + // Hop By Hop extension header with skippable unknown option. + routingExtHdrID, 0, 62, 4, 1, 2, 3, 4, + + // Routing extension header. + fragmentExtHdrID, 0, 1, 0, 2, 3, 4, 5, + + // Fragment extension header. + destinationExtHdrID, 0, 0, 0, 1, 2, 3, 4, + + // Destination extension header with discard action for unknown + // option. + nextHdr, 0, 65, 4, 1, 2, 3, 4, + }, hopByHopExtHdrID + }, + shouldAccept: false, + }, } for _, test := range tests { |