summaryrefslogtreecommitdiffhomepage
path: root/test/packetimpact/testbench/layers.go
diff options
context:
space:
mode:
Diffstat (limited to 'test/packetimpact/testbench/layers.go')
-rw-r--r--test/packetimpact/testbench/layers.go160
1 files changed, 106 insertions, 54 deletions
diff --git a/test/packetimpact/testbench/layers.go b/test/packetimpact/testbench/layers.go
index 4d6625941..5ce324f0d 100644
--- a/test/packetimpact/testbench/layers.go
+++ b/test/packetimpact/testbench/layers.go
@@ -15,6 +15,7 @@
package testbench
import (
+ "encoding/hex"
"fmt"
"reflect"
"strings"
@@ -64,6 +65,9 @@ type Layer interface {
// setPrev sets the pointer to the Layer encapsulating this one.
setPrev(Layer)
+
+ // merge overrides the values in the interface with the provided values.
+ merge(Layer) error
}
// LayerBase is the common elements of all layers.
@@ -91,6 +95,9 @@ func (lb *LayerBase) setPrev(l Layer) {
// equalLayer compares that two Layer structs match while ignoring field in
// which either input has a nil and also ignoring the LayerBase of the inputs.
func equalLayer(x, y Layer) bool {
+ if x == nil || y == nil {
+ return true
+ }
// opt ignores comparison pairs where either of the inputs is a nil.
opt := cmp.FilterValues(func(x, y interface{}) bool {
for _, l := range []interface{}{x, y} {
@@ -104,6 +111,15 @@ func equalLayer(x, y Layer) bool {
return cmp.Equal(x, y, opt, cmpopts.IgnoreTypes(LayerBase{}))
}
+// mergeLayer merges other in layer. Any non-nil value in other overrides the
+// corresponding value in layer. If other is nil, no action is performed.
+func mergeLayer(layer, other Layer) error {
+ if other == nil {
+ return nil
+ }
+ return mergo.Merge(layer, other, mergo.WithOverride)
+}
+
func stringLayer(l Layer) string {
v := reflect.ValueOf(l).Elem()
t := v.Type()
@@ -118,7 +134,12 @@ func stringLayer(l Layer) string {
if v.IsNil() {
continue
}
- ret = append(ret, fmt.Sprintf("%s:%v", t.Name, v))
+ v = reflect.Indirect(v)
+ if v.Kind() == reflect.Slice && v.Type().Elem().Kind() == reflect.Uint8 {
+ ret = append(ret, fmt.Sprintf("%s:\n%v", t.Name, hex.Dump(v.Bytes())))
+ } else {
+ ret = append(ret, fmt.Sprintf("%s:%v", t.Name, v))
+ }
}
return fmt.Sprintf("&%s{%s}", t, strings.Join(ret, " "))
}
@@ -153,7 +174,7 @@ func (l *Ether) toBytes() ([]byte, error) {
fields.Type = header.IPv4ProtocolNumber
default:
// TODO(b/150301488): Support more protocols, like IPv6.
- return nil, fmt.Errorf("can't deduce the ethernet header's next protocol: %d", n)
+ return nil, fmt.Errorf("ethernet header's next layer is unrecognized: %#v", n)
}
}
h.Encode(fields)
@@ -172,27 +193,46 @@ func NetworkProtocolNumber(v tcpip.NetworkProtocolNumber) *tcpip.NetworkProtocol
return &v
}
-// ParseEther parses the bytes assuming that they start with an ethernet header
+// layerParser parses the input bytes and returns a Layer along with the next
+// layerParser to run. If there is no more parsing to do, the returned
+// layerParser is nil.
+type layerParser func([]byte) (Layer, layerParser)
+
+// parse parses bytes starting with the first layerParser and using successive
+// layerParsers until all the bytes are parsed.
+func parse(parser layerParser, b []byte) Layers {
+ var layers Layers
+ for {
+ var layer Layer
+ layer, parser = parser(b)
+ layers = append(layers, layer)
+ if parser == nil {
+ break
+ }
+ b = b[layer.length():]
+ }
+ layers.linkLayers()
+ return layers
+}
+
+// parseEther parses the bytes assuming that they start with an ethernet header
// and continues parsing further encapsulations.
-func ParseEther(b []byte) (Layers, error) {
+func parseEther(b []byte) (Layer, layerParser) {
h := header.Ethernet(b)
ether := Ether{
SrcAddr: LinkAddress(h.SourceAddress()),
DstAddr: LinkAddress(h.DestinationAddress()),
Type: NetworkProtocolNumber(h.Type()),
}
- layers := Layers{&ether}
+ var nextParser layerParser
switch h.Type() {
case header.IPv4ProtocolNumber:
- moreLayers, err := ParseIPv4(b[ether.length():])
- if err != nil {
- return nil, err
- }
- return append(layers, moreLayers...), nil
+ nextParser = parseIPv4
default:
- // TODO(b/150301488): Support more protocols, like IPv6.
- return nil, fmt.Errorf("can't deduce the ethernet header's next protocol: %#v", b)
+ // Assume that the rest is a payload.
+ nextParser = parsePayload
}
+ return &ether, nextParser
}
func (l *Ether) match(other Layer) bool {
@@ -203,6 +243,12 @@ func (l *Ether) length() int {
return header.EthernetMinimumSize
}
+// merge overrides the values in l with the values from other but only in fields
+// where the value is not nil.
+func (l *Ether) merge(other Layer) error {
+ return mergeLayer(l, other)
+}
+
// IPv4 can construct and match an IPv4 encapsulation.
type IPv4 struct {
LayerBase
@@ -274,7 +320,7 @@ func (l *IPv4) toBytes() ([]byte, error) {
fields.Protocol = uint8(header.UDPProtocolNumber)
default:
// TODO(b/150301488): Support more protocols as needed.
- return nil, fmt.Errorf("can't deduce the ip header's next protocol: %#v", n)
+ return nil, fmt.Errorf("ipv4 header's next layer is unrecognized: %#v", n)
}
}
if l.SrcAddr != nil {
@@ -311,9 +357,9 @@ func Address(v tcpip.Address) *tcpip.Address {
return &v
}
-// ParseIPv4 parses the bytes assuming that they start with an ipv4 header and
+// parseIPv4 parses the bytes assuming that they start with an ipv4 header and
// continues parsing further encapsulations.
-func ParseIPv4(b []byte) (Layers, error) {
+func parseIPv4(b []byte) (Layer, layerParser) {
h := header.IPv4(b)
tos, _ := h.TOS()
ipv4 := IPv4{
@@ -329,22 +375,17 @@ func ParseIPv4(b []byte) (Layers, error) {
SrcAddr: Address(h.SourceAddress()),
DstAddr: Address(h.DestinationAddress()),
}
- layers := Layers{&ipv4}
+ var nextParser layerParser
switch h.TransportProtocol() {
case header.TCPProtocolNumber:
- moreLayers, err := ParseTCP(b[ipv4.length():])
- if err != nil {
- return nil, err
- }
- return append(layers, moreLayers...), nil
+ nextParser = parseTCP
case header.UDPProtocolNumber:
- moreLayers, err := ParseUDP(b[ipv4.length():])
- if err != nil {
- return nil, err
- }
- return append(layers, moreLayers...), nil
+ nextParser = parseUDP
+ default:
+ // Assume that the rest is a payload.
+ nextParser = parsePayload
}
- return nil, fmt.Errorf("can't deduce the ethernet header's next protocol: %d", h.Protocol())
+ return &ipv4, nextParser
}
func (l *IPv4) match(other Layer) bool {
@@ -358,6 +399,12 @@ func (l *IPv4) length() int {
return int(*l.IHL)
}
+// merge overrides the values in l with the values from other but only in fields
+// where the value is not nil.
+func (l *IPv4) merge(other Layer) error {
+ return mergeLayer(l, other)
+}
+
// TCP can construct and match a TCP encapsulation.
type TCP struct {
LayerBase
@@ -468,9 +515,9 @@ func Uint32(v uint32) *uint32 {
return &v
}
-// ParseTCP parses the bytes assuming that they start with a tcp header and
+// parseTCP parses the bytes assuming that they start with a tcp header and
// continues parsing further encapsulations.
-func ParseTCP(b []byte) (Layers, error) {
+func parseTCP(b []byte) (Layer, layerParser) {
h := header.TCP(b)
tcp := TCP{
SrcPort: Uint16(h.SourcePort()),
@@ -483,12 +530,7 @@ func ParseTCP(b []byte) (Layers, error) {
Checksum: Uint16(h.Checksum()),
UrgentPointer: Uint16(h.UrgentPointer()),
}
- layers := Layers{&tcp}
- moreLayers, err := ParsePayload(b[tcp.length():])
- if err != nil {
- return nil, err
- }
- return append(layers, moreLayers...), nil
+ return &tcp, parsePayload
}
func (l *TCP) match(other Layer) bool {
@@ -504,8 +546,8 @@ func (l *TCP) length() int {
// merge overrides the values in l with the values from other but only in fields
// where the value is not nil.
-func (l *TCP) merge(other TCP) error {
- return mergo.Merge(l, other, mergo.WithOverride)
+func (l *TCP) merge(other Layer) error {
+ return mergeLayer(l, other)
}
// UDP can construct and match a UDP encapsulation.
@@ -556,9 +598,9 @@ func setUDPChecksum(h *header.UDP, udp *UDP) error {
return nil
}
-// ParseUDP parses the bytes assuming that they start with a udp header and
-// continues parsing further encapsulations.
-func ParseUDP(b []byte) (Layers, error) {
+// parseUDP parses the bytes assuming that they start with a udp header and
+// returns the parsed layer and the next parser to use.
+func parseUDP(b []byte) (Layer, layerParser) {
h := header.UDP(b)
udp := UDP{
SrcPort: Uint16(h.SourcePort()),
@@ -566,12 +608,7 @@ func ParseUDP(b []byte) (Layers, error) {
Length: Uint16(h.Length()),
Checksum: Uint16(h.Checksum()),
}
- layers := Layers{&udp}
- moreLayers, err := ParsePayload(b[udp.length():])
- if err != nil {
- return nil, err
- }
- return append(layers, moreLayers...), nil
+ return &udp, parsePayload
}
func (l *UDP) match(other Layer) bool {
@@ -587,8 +624,8 @@ func (l *UDP) length() int {
// merge overrides the values in l with the values from other but only in fields
// where the value is not nil.
-func (l *UDP) merge(other UDP) error {
- return mergo.Merge(l, other, mergo.WithOverride)
+func (l *UDP) merge(other Layer) error {
+ return mergeLayer(l, other)
}
// Payload has bytes beyond OSI layer 4.
@@ -601,13 +638,13 @@ func (l *Payload) String() string {
return stringLayer(l)
}
-// ParsePayload parses the bytes assuming that they start with a payload and
+// parsePayload parses the bytes assuming that they start with a payload and
// continue to the end. There can be no further encapsulations.
-func ParsePayload(b []byte) (Layers, error) {
+func parsePayload(b []byte) (Layer, layerParser) {
payload := Payload{
Bytes: b,
}
- return Layers{&payload}, nil
+ return &payload, nil
}
func (l *Payload) toBytes() ([]byte, error) {
@@ -622,18 +659,33 @@ func (l *Payload) length() int {
return len(l.Bytes)
}
+// merge overrides the values in l with the values from other but only in fields
+// where the value is not nil.
+func (l *Payload) merge(other Layer) error {
+ return mergeLayer(l, other)
+}
+
// Layers is an array of Layer and supports similar functions to Layer.
type Layers []Layer
-func (ls *Layers) toBytes() ([]byte, error) {
+// linkLayers sets the linked-list ponters in ls.
+func (ls *Layers) linkLayers() {
for i, l := range *ls {
if i > 0 {
l.setPrev((*ls)[i-1])
+ } else {
+ l.setPrev(nil)
}
if i+1 < len(*ls) {
l.setNext((*ls)[i+1])
+ } else {
+ l.setNext(nil)
}
}
+}
+
+func (ls *Layers) toBytes() ([]byte, error) {
+ ls.linkLayers()
outBytes := []byte{}
for _, l := range *ls {
layerBytes, err := l.toBytes()
@@ -649,8 +701,8 @@ func (ls *Layers) match(other Layers) bool {
if len(*ls) > len(other) {
return false
}
- for i := 0; i < len(*ls); i++ {
- if !equalLayer((*ls)[i], other[i]) {
+ for i, l := range *ls {
+ if !equalLayer(l, other[i]) {
return false
}
}
generated by cgit v1.2.3 (git 2.39.1) at 2025-01-02 10:35:01 +0000