1 files changed, 30 insertions, 27 deletions

diff --git a/test/packetimpact/testbench/layers.go b/test/packetimpact/testbench/layers.go
index 2fb7ca9ba..19e6b8d7d 100644
--- a/test/packetimpact/testbench/layers.go
+++ b/test/packetimpact/testbench/layers.go
@@ -298,14 +298,12 @@ func (l *IPv4) ToBytes() ([]byte, error) {
 	// An IPv4 header is variable length depending on the size of the Options.
 	hdrLen := header.IPv4MinimumSize
 	if l.Options != nil {
-		hdrLen += l.Options.AllocationSize()
+		if len(*l.Options)%4 != 0 {
+			return nil, fmt.Errorf("invalid header options '%x (len=%d)'; must be 32 bit aligned", *l.Options, len(*l.Options))
+		}
+		hdrLen += len(*l.Options)
 		if hdrLen > header.IPv4MaximumHeaderSize {
-			// While ToBytes can be called on packets that were received as well
-			// as packets locally generated, it is physically impossible for a
-			// received packet to overflow this value so any such failure must
-			// be the result of a local programming error and not remotely
-			// triggered. A panic is therefore appropriate.
-			panic(fmt.Sprintf("IPv4 Options %d bytes, Max %d", len(*l.Options), header.IPv4MaximumOptionsSize))
+			return nil, fmt.Errorf("IPv4 Options %d bytes, Max %d", len(*l.Options), header.IPv4MaximumOptionsSize)
 		}
 	}
 	b := make([]byte, hdrLen)
@@ -323,10 +321,6 @@ func (l *IPv4) ToBytes() ([]byte, error) {
 		DstAddr:        tcpip.Address(""),
 		Options:        nil,
 	}
-	// Leave an empty options slice as nil.
-	if hdrLen > header.IPv4MinimumSize {
-		fields.Options = *l.Options
-	}
 	if l.TOS != nil {
 		fields.TOS = *l.TOS
 	}
@@ -373,18 +367,31 @@ func (l *IPv4) ToBytes() ([]byte, error) {
 	if l.DstAddr != nil {
 		fields.DstAddr = *l.DstAddr
 	}
-	if l.Checksum != nil {
-		fields.Checksum = *l.Checksum
-	}
+
 	h.Encode(fields)
-	if l.Checksum == nil {
-		h.SetChecksum(^h.CalculateChecksum())
+
+	// Put raw option bytes from test definition in header. Options as raw bytes
+	// allows us to serialize malformed options, which is not possible with
+	// the provided serialization functions.
+	if l.Options != nil {
+		h.SetHeaderLength(h.HeaderLength() + uint8(len(*l.Options)))
+		if got, want := copy(h.Options(), *l.Options), len(*l.Options); got != want {
+			return nil, fmt.Errorf("failed to copy option bytes into header, got %d want %d", got, want)
+		}
 	}
+
 	// Encode cannot set this incorrectly so we need to overwrite what it wrote
 	// in order to test handling of a bad IHL value.
 	if l.IHL != nil {
 		h.SetHeaderLength(*l.IHL)
 	}
+
+	if l.Checksum == nil {
+		h.SetChecksum(^h.CalculateChecksum())
+	} else {
+		h.SetChecksum(*l.Checksum)
+	}
+
 	return h, nil
 }
 
@@ -410,13 +417,7 @@ func Address(v tcpip.Address) *tcpip.Address {
 // continues parsing further encapsulations.
 func parseIPv4(b []byte) (Layer, layerParser) {
 	h := header.IPv4(b)
-	hdrLen := h.HeaderLength()
-	// Even if there are no options, we set an empty options field instead of nil
-	// so that the decision to compare is up to the caller of that comparison.
-	var options header.IPv4Options
-	if hdrLen > header.IPv4MinimumSize {
-		options = append(options, h.Options()...)
-	}
+	options := h.Options()
 	tos, _ := h.TOS()
 	ipv4 := IPv4{
 		IHL:            Uint8(h.HeaderLength()),
@@ -504,13 +505,13 @@ func (l *IPv6) ToBytes() ([]byte, error) {
 		}
 	}
 	if l.NextHeader != nil {
-		fields.NextHeader = *l.NextHeader
+		fields.TransportProtocol = tcpip.TransportProtocolNumber(*l.NextHeader)
 	} else {
 		nh, err := nextHeaderByLayer(l.next())
 		if err != nil {
 			return nil, err
 		}
-		fields.NextHeader = nh
+		fields.TransportProtocol = tcpip.TransportProtocolNumber(nh)
 	}
 	if l.HopLimit != nil {
 		fields.HopLimit = *l.HopLimit
@@ -836,7 +837,9 @@ func (l *ICMPv6) ToBytes() ([]byte, error) {
 	if l.Code != nil {
 		h.SetCode(*l.Code)
 	}
-	copy(h.NDPPayload(), l.Payload)
+	if n := copy(h.MessageBody(), l.Payload); n != len(l.Payload) {
+		panic(fmt.Sprintf("copied %d bytes, expected to copy %d bytes", n, len(l.Payload)))
+	}
 	if l.Checksum != nil {
 		h.SetChecksum(*l.Checksum)
 	} else {
@@ -882,7 +885,7 @@ func parseICMPv6(b []byte) (Layer, layerParser) {
 		Type:     ICMPv6Type(h.Type()),
 		Code:     ICMPv6Code(h.Code()),
 		Checksum: Uint16(h.Checksum()),
-		Payload:  h.NDPPayload(),
+		Payload:  h.MessageBody(),
 	}
 	return &icmpv6, nil
 }