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mirror of https://github.com/netsampler/goflow2.git synced 2024-05-06 15:54:52 +00:00

528 lines
16 KiB
Go

package protoproducer
import (
"encoding/binary"
"github.com/netsampler/goflow2/v2/decoders/sflow"
flowmessage "github.com/netsampler/goflow2/v2/pb"
"github.com/netsampler/goflow2/v2/producer"
)
func GetSFlowFlowSamples(packet *sflow.Packet) []interface{} {
var flowSamples []interface{}
for _, sample := range packet.Samples {
switch sample.(type) {
case sflow.FlowSample:
flowSamples = append(flowSamples, sample)
case sflow.ExpandedFlowSample:
flowSamples = append(flowSamples, sample)
}
}
return flowSamples
}
func ParseSampledHeader(flowMessage *ProtoProducerMessage, sampledHeader *sflow.SampledHeader) error {
return ParseSampledHeaderConfig(flowMessage, sampledHeader, nil)
}
func ParseEthernet(offset int, flowMessage *ProtoProducerMessage, data []byte) (etherType []byte, newOffset int, err error) {
if len(data) >= offset+14 {
etherType = data[offset+12 : offset+14]
dstMac := binary.BigEndian.Uint64(append([]byte{0, 0}, data[offset+0:offset+6]...))
srcMac := binary.BigEndian.Uint64(append([]byte{0, 0}, data[offset+6:offset+12]...))
flowMessage.SrcMac = srcMac
flowMessage.DstMac = dstMac
offset += 14
}
return etherType, offset, err
}
func Parse8021Q(offset int, flowMessage *ProtoProducerMessage, data []byte) (etherType []byte, newOffset int, err error) {
if len(data) >= offset+4 {
flowMessage.VlanId = uint32(binary.BigEndian.Uint16(data[offset : offset+2]))
etherType = data[offset+2 : offset+4]
offset += 4
}
return etherType, offset, err
}
func ParseMPLS(offset int, flowMessage *ProtoProducerMessage, data []byte) (etherType []byte, newOffset int, err error) {
var mplsLabel []uint32
var mplsTtl []uint32
iterateMpls := true
for iterateMpls {
if len(data) < offset+5 {
// stop iterating mpls, not enough payload left
break
}
label := binary.BigEndian.Uint32(append([]byte{0}, data[offset:offset+3]...)) >> 4
//exp := data[offset+2] > 1
bottom := data[offset+2] & 1
ttl := data[offset+3]
offset += 4
if bottom == 1 || label <= 15 || offset > len(data) {
if data[offset]&0xf0>>4 == 4 {
etherType = []byte{0x8, 0x0}
} else if data[offset]&0xf0>>4 == 6 {
etherType = []byte{0x86, 0xdd}
}
iterateMpls = false // stop iterating mpls, bottom of stack
}
mplsLabel = append(mplsLabel, label)
mplsTtl = append(mplsTtl, uint32(ttl))
}
// if multiple MPLS headers, will reset existing values
flowMessage.MplsLabel = mplsLabel
flowMessage.MplsTtl = mplsTtl
return etherType, offset, err
}
func ParseIPv4(offset int, flowMessage *ProtoProducerMessage, data []byte) (nextHeader byte, newOffset int, err error) {
if len(data) >= offset+20 {
nextHeader = data[offset+9]
flowMessage.SrcAddr = data[offset+12 : offset+16]
flowMessage.DstAddr = data[offset+16 : offset+20]
tos := data[offset+1]
ttl := data[offset+8]
flowMessage.IpTos = uint32(tos)
flowMessage.IpTtl = uint32(ttl)
identification := binary.BigEndian.Uint16(data[offset+4 : offset+6])
fragOffset := binary.BigEndian.Uint16(data[offset+6 : offset+8]) // also includes flag
flowMessage.FragmentId = uint32(identification)
flowMessage.FragmentOffset = uint32(fragOffset) & 8191
flowMessage.IpFlags = uint32(fragOffset) >> 13
offset += 20
}
return nextHeader, offset, err
}
func ParseIPv6(offset int, flowMessage *ProtoProducerMessage, data []byte) (nextHeader byte, newOffset int, err error) {
if len(data) >= offset+40 {
nextHeader = data[offset+6]
flowMessage.SrcAddr = data[offset+8 : offset+24]
flowMessage.DstAddr = data[offset+24 : offset+40]
tostmp := uint32(binary.BigEndian.Uint16(data[offset : offset+2]))
tos := uint8(tostmp & 0x0ff0 >> 4)
ttl := data[offset+7]
flowMessage.IpTos = uint32(tos)
flowMessage.IpTtl = uint32(ttl)
flowLabel := binary.BigEndian.Uint32(data[offset : offset+4])
flowMessage.Ipv6FlowLabel = flowLabel & 0xFFFFF
offset += 40
}
return nextHeader, offset, err
}
func ParseIPv6Headers(nextHeader byte, offset int, flowMessage *ProtoProducerMessage, data []byte) (newNextHeader byte, newOffset int, err error) {
for {
if nextHeader == 44 && len(data) >= offset+8 {
nextHeader = data[offset]
fragOffset := binary.BigEndian.Uint16(data[offset+2 : offset+4]) // also includes flag
identification := binary.BigEndian.Uint32(data[offset+4 : offset+8])
flowMessage.FragmentId = identification
flowMessage.FragmentOffset = uint32(fragOffset) >> 3
flowMessage.IpFlags = uint32(fragOffset) & 7
offset += 8
} else {
break
}
}
return nextHeader, offset, err
}
func ParseTCP(offset int, flowMessage *ProtoProducerMessage, data []byte) (newOffset int, err error) {
if len(data) >= offset+13 {
srcPort := binary.BigEndian.Uint16(data[offset+0 : offset+2])
dstPort := binary.BigEndian.Uint16(data[offset+2 : offset+4])
flowMessage.SrcPort = uint32(srcPort)
flowMessage.DstPort = uint32(dstPort)
tcpflags := data[offset+13]
flowMessage.TcpFlags = uint32(tcpflags)
length := int(data[13]>>4) * 4
offset += length
}
return offset, err
}
func ParseUDP(offset int, flowMessage *ProtoProducerMessage, data []byte) (newOffset int, err error) {
if len(data) >= offset+4 {
srcPort := binary.BigEndian.Uint16(data[offset+0 : offset+2])
dstPort := binary.BigEndian.Uint16(data[offset+2 : offset+4])
flowMessage.SrcPort = uint32(srcPort)
flowMessage.DstPort = uint32(dstPort)
offset += 8
}
return offset, err
}
func ParseICMP(offset int, flowMessage *ProtoProducerMessage, data []byte) (newOffset int, err error) {
if len(data) >= offset+2 {
flowMessage.IcmpType = uint32(data[offset+0])
flowMessage.IcmpCode = uint32(data[offset+1])
offset += 8
}
return offset, err
}
func ParseICMPv6(offset int, flowMessage *ProtoProducerMessage, data []byte) (newOffset int, err error) {
if len(data) >= offset+2 {
flowMessage.IcmpType = uint32(data[offset+0])
flowMessage.IcmpCode = uint32(data[offset+1])
offset += 8
}
return offset, err
}
func IsMPLS(etherType []byte) bool {
if len(etherType) != 2 {
return false
}
return etherType[0] == 0x88 && etherType[1] == 0x47
}
func Is8021Q(etherType []byte) bool {
if len(etherType) != 2 {
return false
}
return etherType[0] == 0x81 && etherType[1] == 0x0
}
func IsIPv4(etherType []byte) bool {
if len(etherType) != 2 {
return false
}
return etherType[0] == 0x8 && etherType[1] == 0x0
}
func IsIPv6(etherType []byte) bool {
if len(etherType) != 2 {
return false
}
return etherType[0] == 0x86 && etherType[1] == 0xdd
}
func IsARP(etherType []byte) bool {
if len(etherType) != 2 {
return false
}
return etherType[0] == 0x8 && etherType[1] == 0x6
}
// Parses an entire stream consisting of multiple layers of protocols
// It picks the best field to map when multiple encapsulation of the same layer (eg: tunnels, extension headers, etc.)
func ParseEthernetHeader(flowMessage *ProtoProducerMessage, data []byte, config *SFlowMapper) (err error) {
var nextHeader byte
var offset int
var etherType []byte
for _, configLayer := range GetSFlowConfigLayer(config, "0") {
extracted := GetBytes(data, offset+configLayer.Offset, configLayer.Length)
if err := MapCustom(flowMessage, extracted, configLayer.MapConfigBase); err != nil {
return err
}
}
if etherType, offset, err = ParseEthernet(offset, flowMessage, data); err != nil {
return err
}
if len(etherType) != 2 {
return nil
}
encap := true
iterations := 0
for encap && iterations <= 1 {
encap = false
if Is8021Q(etherType) { // VLAN 802.1Q
if etherType, offset, err = Parse8021Q(offset, flowMessage, data); err != nil {
return err
}
}
if IsMPLS(etherType) { // MPLS
if etherType, offset, err = ParseMPLS(offset, flowMessage, data); err != nil {
return err
}
}
for _, configLayer := range GetSFlowConfigLayer(config, "3") {
extracted := GetBytes(data, offset*8+configLayer.Offset, configLayer.Length)
if err := MapCustom(flowMessage, extracted, configLayer.MapConfigBase); err != nil {
return err
}
}
if IsIPv4(etherType) { // IPv4
prevOffset := offset
if nextHeader, offset, err = ParseIPv4(offset, flowMessage, data); err != nil {
return err
}
for _, configLayer := range GetSFlowConfigLayer(config, "ipv4") {
extracted := GetBytes(data, prevOffset*8+configLayer.Offset, configLayer.Length)
if err := MapCustom(flowMessage, extracted, configLayer.MapConfigBase); err != nil {
return err
}
}
} else if IsIPv6(etherType) { // IPv6
prevOffset := offset
if nextHeader, offset, err = ParseIPv6(offset, flowMessage, data); err != nil {
return err
}
if nextHeader, offset, err = ParseIPv6Headers(nextHeader, offset, flowMessage, data); err != nil {
return err
}
for _, configLayer := range GetSFlowConfigLayer(config, "ipv6") {
extracted := GetBytes(data, prevOffset*8+configLayer.Offset, configLayer.Length)
if err := MapCustom(flowMessage, extracted, configLayer.MapConfigBase); err != nil {
return err
}
}
} else if IsARP(etherType) { // ARP
for _, configLayer := range GetSFlowConfigLayer(config, "arp") {
extracted := GetBytes(data, offset*8+configLayer.Offset, configLayer.Length)
if err := MapCustom(flowMessage, extracted, configLayer.MapConfigBase); err != nil {
return err
}
}
}
for _, configLayer := range GetSFlowConfigLayer(config, "4") {
extracted := GetBytes(data, offset*8+configLayer.Offset, configLayer.Length)
if err := MapCustom(flowMessage, extracted, configLayer.MapConfigBase); err != nil {
return err
}
}
var appOffset int // keeps track of the user payload
// Transport protocols
if nextHeader == 17 || nextHeader == 6 || nextHeader == 1 || nextHeader == 58 {
prevOffset := offset
if flowMessage.FragmentOffset == 0 {
if nextHeader == 17 { // UDP
if offset, err = ParseUDP(offset, flowMessage, data); err != nil {
return err
}
for _, configLayer := range GetSFlowConfigLayer(config, "udp") {
extracted := GetBytes(data, prevOffset*8+configLayer.Offset, configLayer.Length)
if err := MapCustom(flowMessage, extracted, configLayer.MapConfigBase); err != nil {
return err
}
}
} else if nextHeader == 6 { // TCP
if offset, err = ParseTCP(offset, flowMessage, data); err != nil {
return err
}
for _, configLayer := range GetSFlowConfigLayer(config, "tcp") {
extracted := GetBytes(data, prevOffset*8+configLayer.Offset, configLayer.Length)
if err := MapCustom(flowMessage, extracted, configLayer.MapConfigBase); err != nil {
return err
}
}
} else if nextHeader == 1 { // ICMP
if offset, err = ParseICMP(offset, flowMessage, data); err != nil {
return err
}
for _, configLayer := range GetSFlowConfigLayer(config, "icmp") {
extracted := GetBytes(data, prevOffset*8+configLayer.Offset, configLayer.Length)
if err := MapCustom(flowMessage, extracted, configLayer.MapConfigBase); err != nil {
return err
}
}
} else if nextHeader == 58 { // ICMPv6
if offset, err = ParseICMPv6(offset, flowMessage, data); err != nil {
return err
}
for _, configLayer := range GetSFlowConfigLayer(config, "icmp6") {
extracted := GetBytes(data, prevOffset*8+configLayer.Offset, configLayer.Length)
if err := MapCustom(flowMessage, extracted, configLayer.MapConfigBase); err != nil {
return err
}
}
}
}
appOffset = offset
}
// fetch data from the application/payload
if appOffset > 0 {
for _, configLayer := range GetSFlowConfigLayer(config, "7") {
customOffset := appOffset*8 + configLayer.Offset - int(flowMessage.FragmentOffset)*8 // allows user to get data from a fragment as well
// todo: check the calculation (might be off due to various header size)
extracted := GetBytes(data, customOffset, configLayer.Length)
if err := MapCustom(flowMessage, extracted, configLayer.MapConfigBase); err != nil {
return err
}
}
}
iterations++
}
if len(etherType) >= 2 {
flowMessage.Etype = uint32(binary.BigEndian.Uint16(etherType[0:2]))
}
flowMessage.Proto = uint32(nextHeader)
return nil
}
func ParseSampledHeaderConfig(flowMessage *ProtoProducerMessage, sampledHeader *sflow.SampledHeader, config *SFlowMapper) error {
data := (*sampledHeader).HeaderData
switch (*sampledHeader).Protocol {
case 1: // Ethernet
if err := ParseEthernetHeader(flowMessage, data, config); err != nil {
return err
}
}
return nil
}
func SearchSFlowSampleConfig(flowMessage *ProtoProducerMessage, flowSample interface{}, config *SFlowMapper) error {
var records []sflow.FlowRecord
flowMessage.Type = flowmessage.FlowMessage_SFLOW_5
switch flowSample := flowSample.(type) {
case sflow.FlowSample:
records = flowSample.Records
flowMessage.SamplingRate = uint64(flowSample.SamplingRate)
flowMessage.InIf = flowSample.Input
flowMessage.OutIf = flowSample.Output
case sflow.ExpandedFlowSample:
records = flowSample.Records
flowMessage.SamplingRate = uint64(flowSample.SamplingRate)
flowMessage.InIf = flowSample.InputIfValue
flowMessage.OutIf = flowSample.OutputIfValue
}
var ipNh, ipSrc, ipDst []byte
flowMessage.Packets = 1
for _, record := range records {
switch recordData := record.Data.(type) {
case sflow.SampledHeader:
flowMessage.Bytes = uint64(recordData.FrameLength)
if err := ParseSampledHeaderConfig(flowMessage, &recordData, config); err != nil { // todo: make function configurable
return err
}
case sflow.SampledIPv4:
ipSrc = recordData.SrcIP
ipDst = recordData.DstIP
flowMessage.SrcAddr = ipSrc
flowMessage.DstAddr = ipDst
flowMessage.Bytes = uint64(recordData.Length)
flowMessage.Proto = recordData.Protocol
flowMessage.SrcPort = recordData.SrcPort
flowMessage.DstPort = recordData.DstPort
flowMessage.IpTos = recordData.Tos
flowMessage.Etype = 0x800
case sflow.SampledIPv6:
ipSrc = recordData.SrcIP
ipDst = recordData.DstIP
flowMessage.SrcAddr = ipSrc
flowMessage.DstAddr = ipDst
flowMessage.Bytes = uint64(recordData.Length)
flowMessage.Proto = recordData.Protocol
flowMessage.SrcPort = recordData.SrcPort
flowMessage.DstPort = recordData.DstPort
flowMessage.IpTos = recordData.Priority
flowMessage.Etype = 0x86dd
case sflow.ExtendedRouter:
ipNh = recordData.NextHop
flowMessage.NextHop = ipNh
flowMessage.SrcNet = recordData.SrcMaskLen
flowMessage.DstNet = recordData.DstMaskLen
case sflow.ExtendedGateway:
ipNh = recordData.NextHop
flowMessage.BgpNextHop = ipNh
flowMessage.BgpCommunities = recordData.Communities
flowMessage.AsPath = recordData.ASPath
if len(recordData.ASPath) > 0 {
flowMessage.DstAs = recordData.ASPath[len(recordData.ASPath)-1]
flowMessage.NextHopAs = recordData.ASPath[0]
} else {
flowMessage.DstAs = recordData.AS
}
if recordData.SrcAS > 0 {
flowMessage.SrcAs = recordData.SrcAS
} else {
flowMessage.SrcAs = recordData.AS
}
case sflow.ExtendedSwitch:
flowMessage.SrcVlan = recordData.SrcVlan
flowMessage.DstVlan = recordData.DstVlan
}
}
return nil
}
func SearchSFlowSamplesConfig(samples []interface{}, config *SFlowMapper) (flowMessageSet []producer.ProducerMessage, err error) {
for _, flowSample := range samples {
fmsg := protoMessagePool.Get().(*ProtoProducerMessage)
fmsg.Reset()
if err := SearchSFlowSampleConfig(fmsg, flowSample, config); err != nil {
return nil, err
}
flowMessageSet = append(flowMessageSet, fmsg)
}
return flowMessageSet, nil
}
// Converts an sFlow message
func ProcessMessageSFlowConfig(packet *sflow.Packet, config *producerConfigMapped) (flowMessageSet []producer.ProducerMessage, err error) {
seqnum := packet.SequenceNumber
agent := packet.AgentIP
var cfg *SFlowMapper
if config != nil {
cfg = config.SFlow
}
flowSamples := GetSFlowFlowSamples(packet)
flowMessageSet, err = SearchSFlowSamplesConfig(flowSamples, cfg)
if err != nil {
return flowMessageSet, err
}
for _, msg := range flowMessageSet {
fmsg, ok := msg.(*ProtoProducerMessage)
if !ok {
continue
}
fmsg.SamplerAddress = agent
fmsg.SequenceNum = seqnum
}
return flowMessageSet, nil
}