forked from google/gopacket
/
sflow.go
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/
sflow.go
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// Copyright 2014 Google, Inc. All rights reserved.
//
// Use of this source code is governed by a BSD-style license
// that can be found in the LICENSE file in the root of the source
// tree.
/*
This layer decodes SFlow version 5 datagrams.
The specification can be found here: http://sflow.org/sflow_version_5.txt
Additional developer information about sflow can be found at:
http://sflow.org/developers/specifications.php
And SFlow in general:
http://sflow.org/index.php
Two forms of sample data are defined: compact and expanded. The
Specification has this to say:
Compact and expand forms of counter and flow samples are defined.
An agent must not mix compact/expanded encodings. If an agent
will never use ifIndex numbers >= 2^24 then it must use compact
encodings for all interfaces. Otherwise the expanded formats must
be used for all interfaces.
This decoder only supports the compact form, because that is the only
one for which data was avaialble.
The datagram is composed of one or more samples of type flow or counter,
and each sample is composed of one or more records describing the sample.
A sample is a single instance of sampled inforamtion, and each record in
the sample gives additional / supplimentary information about the sample.
The following sample record types are supported:
Raw Packet Header
opaque = flow_data; enterprise = 0; format = 1
Extended Switch Data
opaque = flow_data; enterprise = 0; format = 1001
Extended Router Data
opaque = flow_data; enterprise = 0; format = 1002
Extended Gateway Data
opaque = flow_data; enterprise = 0; format = 1003
Extended User Data
opaque = flow_data; enterprise = 0; format = 1004
Extended URL Data
opaque = flow_data; enterprise = 0; format = 1005
The following types of counter records are supported:
Generic Interface Counters - see RFC 2233
opaque = counter_data; enterprise = 0; format = 1
Ethernet Interface Counters - see RFC 2358
opaque = counter_data; enterprise = 0; format = 2
SFlow is encoded using XDR (RFC4506). There are a few places
where the standard 4-byte fields are partitioned into two
bitfields of different lengths. I'm not sure why the designers
chose to pack together two values like this in some places, and
in others they use the entire 4-byte value to store a number that
will never be more than a few bits. In any case, there are a couple
of types defined to handle the decoding of these bitfields, and
that's why they're there. */
package layers
import (
"encoding/binary"
"errors"
"fmt"
"net"
"github.com/google/gopacket"
)
// SFlowRecord holds both flow sample records and counter sample records.
// A Record is the structure that actually holds the sampled data
// and / or counters.
type SFlowRecord interface {
}
// SFlowDataSource encodes a 2-bit SFlowSourceFormat in its most significant
// 2 bits, and an SFlowSourceValue in its least significant 30 bits.
// These types and values define the meaning of the inteface information
// presented in the sample metadata.
type SFlowDataSource int32
func (sdc SFlowDataSource) decode() (SFlowSourceFormat, SFlowSourceValue) {
leftField := sdc >> 30
rightField := uint32(0x3FFFFFFF) & uint32(sdc)
return SFlowSourceFormat(leftField), SFlowSourceValue(rightField)
}
type SFlowDataSourceExpanded struct {
SourceIDClass SFlowSourceFormat
SourceIDIndex SFlowSourceValue
}
func (sdce SFlowDataSourceExpanded) decode() (SFlowSourceFormat, SFlowSourceValue) {
leftField := sdce.SourceIDClass >> 30
rightField := uint32(0x3FFFFFFF) & uint32(sdce.SourceIDIndex)
return SFlowSourceFormat(leftField), SFlowSourceValue(rightField)
}
type SFlowSourceFormat uint32
type SFlowSourceValue uint32
const (
SFlowTypeSingleInterface SFlowSourceFormat = 0
SFlowTypePacketDiscarded SFlowSourceFormat = 1
SFlowTypeMultipleDestinations SFlowSourceFormat = 2
)
func (sdf SFlowSourceFormat) String() string {
switch sdf {
case SFlowTypeSingleInterface:
return "Single Interface"
case SFlowTypePacketDiscarded:
return "Packet Discarded"
case SFlowTypeMultipleDestinations:
return "Multiple Destinations"
default:
return "UNKNOWN"
}
}
func decodeSFlow(data []byte, p gopacket.PacketBuilder) error {
s := &SFlowDatagram{}
err := s.DecodeFromBytes(data, p)
if err != nil {
return err
}
p.AddLayer(s)
p.SetApplicationLayer(s)
return nil
}
// SFlowDatagram is the outermost container which holds some basic information
// about the reporting agent, and holds at least one sample record
type SFlowDatagram struct {
BaseLayer
DatagramVersion uint32
AgentAddress net.IP
SubAgentID uint32
SequenceNumber uint32
AgentUptime uint32
SampleCount uint32
FlowSamples []SFlowFlowSample
CounterSamples []SFlowCounterSample
}
// An SFlow datagram's outer container has the following
// structure:
// 0 15 31
// +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+
// | int sFlow version (2|4|5) |
// +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+
// | int IP version of the Agent (1=v4|2=v6) |
// +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+
// / Agent IP address (v4=4byte|v6=16byte) /
// / /
// +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+
// | int sub agent id |
// +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+
// | int datagram sequence number |
// +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+
// | int switch uptime in ms |
// +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+
// | int n samples in datagram |
// +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+
// / n samples /
// / /
// +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+
// SFlowDataFormat encodes the EnterpriseID in the most
// significant 12 bits, and the SampleType in the least significant
// 20 bits.
type SFlowDataFormat uint32
func (sdf SFlowDataFormat) decode() (SFlowEnterpriseID, SFlowSampleType) {
leftField := sdf >> 12
rightField := uint32(0xFFF) & uint32(sdf)
return SFlowEnterpriseID(leftField), SFlowSampleType(rightField)
}
// SFlowEnterpriseID is used to differentiate between the
// official SFlow standard, and other, vendor-specific
// types of flow data. (Similiar to SNMP's enterprise MIB
// OIDs) Only the office SFlow Enterprise ID is decoded
// here.
type SFlowEnterpriseID uint32
const (
SFlowStandard SFlowEnterpriseID = 0
)
func (eid SFlowEnterpriseID) String() string {
switch eid {
case SFlowStandard:
return "Standard SFlow"
default:
return ""
}
}
func (eid SFlowEnterpriseID) GetType() SFlowEnterpriseID {
return SFlowStandard
}
// SFlowSampleType specifies the type of sample. Only flow samples
// and counter samples are supported
type SFlowSampleType uint32
const (
SFlowTypeFlowSample SFlowSampleType = 1
SFlowTypeCounterSample SFlowSampleType = 2
SFlowTypeExpandedFlowSample SFlowSampleType = 3
SFlowTypeExpandedCounterSample SFlowSampleType = 4
)
func (st SFlowSampleType) GetType() SFlowSampleType {
switch st {
case SFlowTypeFlowSample:
return SFlowTypeFlowSample
case SFlowTypeCounterSample:
return SFlowTypeCounterSample
case SFlowTypeExpandedFlowSample:
return SFlowTypeExpandedFlowSample
case SFlowTypeExpandedCounterSample:
return SFlowTypeExpandedCounterSample
default:
panic("Invalid Sample Type")
}
}
func (st SFlowSampleType) String() string {
switch st {
case SFlowTypeFlowSample:
return "Flow Sample"
case SFlowTypeCounterSample:
return "Counter Sample"
case SFlowTypeExpandedFlowSample:
return "Expanded Flow Sample"
case SFlowTypeExpandedCounterSample:
return "Expanded Counter Sample"
default:
return ""
}
}
func (s *SFlowDatagram) LayerType() gopacket.LayerType { return LayerTypeSFlow }
func (d *SFlowDatagram) Payload() []byte { return nil }
func (d *SFlowDatagram) CanDecode() gopacket.LayerClass { return LayerTypeSFlow }
func (d *SFlowDatagram) NextLayerType() gopacket.LayerType { return gopacket.LayerTypePayload }
// SFlowIPType determines what form the IP address being decoded will
// take. This is an XDR union type allowing for both IPv4 and IPv6
type SFlowIPType uint32
const (
SFlowIPv4 SFlowIPType = 1
SFlowIPv6 SFlowIPType = 2
)
func (s SFlowIPType) String() string {
switch s {
case SFlowIPv4:
return "IPv4"
case SFlowIPv6:
return "IPv6"
default:
return ""
}
}
func (s SFlowIPType) Length() int {
switch s {
case SFlowIPv4:
return 4
case SFlowIPv6:
return 16
default:
return 0
}
}
func (s *SFlowDatagram) DecodeFromBytes(data []byte, df gopacket.DecodeFeedback) error {
var agentAddressType SFlowIPType
data, s.DatagramVersion = data[4:], binary.BigEndian.Uint32(data[:4])
data, agentAddressType = data[4:], SFlowIPType(binary.BigEndian.Uint32(data[:4]))
data, s.AgentAddress = data[agentAddressType.Length():], data[:agentAddressType.Length()]
data, s.SubAgentID = data[4:], binary.BigEndian.Uint32(data[:4])
data, s.SequenceNumber = data[4:], binary.BigEndian.Uint32(data[:4])
data, s.AgentUptime = data[4:], binary.BigEndian.Uint32(data[:4])
data, s.SampleCount = data[4:], binary.BigEndian.Uint32(data[:4])
if s.SampleCount < 1 {
return fmt.Errorf("SFlow Datagram has invalid sample length: %d", s.SampleCount)
}
for i := uint32(0); i < s.SampleCount; i++ {
sdf := SFlowDataFormat(binary.BigEndian.Uint32(data[:4]))
_, sampleType := sdf.decode()
switch sampleType {
case SFlowTypeFlowSample:
if flowSample, err := decodeFlowSample(&data, false); err == nil {
s.FlowSamples = append(s.FlowSamples, flowSample)
} else {
return err
}
case SFlowTypeCounterSample:
if counterSample, err := decodeCounterSample(&data, false); err == nil {
s.CounterSamples = append(s.CounterSamples, counterSample)
} else {
return err
}
case SFlowTypeExpandedFlowSample:
if flowSample, err := decodeFlowSample(&data, true); err == nil {
s.FlowSamples = append(s.FlowSamples, flowSample)
} else {
return err
}
case SFlowTypeExpandedCounterSample:
if counterSample, err := decodeCounterSample(&data, true); err == nil {
s.CounterSamples = append(s.CounterSamples, counterSample)
} else {
return err
}
default:
return fmt.Errorf("Unsupported SFlow sample type %d", sampleType)
}
}
return nil
}
// SFlowFlowSample represents a sampled packet and contains
// one or more records describing the packet
type SFlowFlowSample struct {
EnterpriseID SFlowEnterpriseID
Format SFlowSampleType
SampleLength uint32
SequenceNumber uint32
SourceIDClass SFlowSourceFormat
SourceIDIndex SFlowSourceValue
SamplingRate uint32
SamplePool uint32
Dropped uint32
InputInterfaceFormat uint32
InputInterface uint32
OutputInterfaceFormat uint32
OutputInterface uint32
RecordCount uint32
Records []SFlowRecord
}
// Flow samples have the following structure. Note
// the bit fields to encode the Enterprise ID and the
// Flow record format: type 1
// 0 15 31
// +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+
// | 20 bit Interprise (0) |12 bit format |
// +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+
// | sample length |
// +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+
// | int sample sequence number |
// +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+
// |id type | src id index value |
// +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+
// | int sampling rate |
// +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+
// | int sample pool |
// +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+
// | int drops |
// +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+
// | int input ifIndex |
// +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+
// | int output ifIndex |
// +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+
// | int number of records |
// +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+
// / flow records /
// / /
// +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+
// Flow samples have the following structure.
// Flow record format: type 3
// 0 15 31
// +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+
// | 20 bit Interprise (0) |12 bit format |
// +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+
// | sample length |
// +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+
// | int sample sequence number |
// +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+
// | int src id type |
// +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+
// | int src id index value |
// +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+
// | int sampling rate |
// +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+
// | int sample pool |
// +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+
// | int drops |
// +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+
// | int input interface format |
// +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+
// | int input interface value |
// +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+
// | int output interface format |
// +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+
// | int output interface value |
// +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+
// | int number of records |
// +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+
// / flow records /
// / /
// +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+
type SFlowFlowDataFormat uint32
func (fdf SFlowFlowDataFormat) decode() (SFlowEnterpriseID, SFlowFlowRecordType) {
leftField := fdf >> 12
rightField := uint32(0xFFF) & uint32(fdf)
return SFlowEnterpriseID(leftField), SFlowFlowRecordType(rightField)
}
func (fs SFlowFlowSample) GetRecords() []SFlowRecord {
return fs.Records
}
func (fs SFlowFlowSample) GetType() SFlowSampleType {
return SFlowTypeFlowSample
}
func skipRecord(data *[]byte) {
recordLength := int(binary.BigEndian.Uint32((*data)[4:]))
*data = (*data)[(recordLength+((4-recordLength)%4))+8:]
}
func decodeFlowSample(data *[]byte, expanded bool) (SFlowFlowSample, error) {
s := SFlowFlowSample{}
var sdf SFlowDataFormat
*data, sdf = (*data)[4:], SFlowDataFormat(binary.BigEndian.Uint32((*data)[:4]))
var sdc SFlowDataSource
s.EnterpriseID, s.Format = sdf.decode()
*data, s.SampleLength = (*data)[4:], binary.BigEndian.Uint32((*data)[:4])
*data, s.SequenceNumber = (*data)[4:], binary.BigEndian.Uint32((*data)[:4])
if expanded {
*data, s.SourceIDClass = (*data)[4:], SFlowSourceFormat(binary.BigEndian.Uint32((*data)[:4]))
*data, s.SourceIDIndex = (*data)[4:], SFlowSourceValue(binary.BigEndian.Uint32((*data)[:4]))
} else {
*data, sdc = (*data)[4:], SFlowDataSource(binary.BigEndian.Uint32((*data)[:4]))
s.SourceIDClass, s.SourceIDIndex = sdc.decode()
}
*data, s.SamplingRate = (*data)[4:], binary.BigEndian.Uint32((*data)[:4])
*data, s.SamplePool = (*data)[4:], binary.BigEndian.Uint32((*data)[:4])
*data, s.Dropped = (*data)[4:], binary.BigEndian.Uint32((*data)[:4])
if expanded {
*data, s.InputInterfaceFormat = (*data)[4:], binary.BigEndian.Uint32((*data)[:4])
*data, s.InputInterface = (*data)[4:], binary.BigEndian.Uint32((*data)[:4])
*data, s.OutputInterfaceFormat = (*data)[4:], binary.BigEndian.Uint32((*data)[:4])
*data, s.OutputInterface = (*data)[4:], binary.BigEndian.Uint32((*data)[:4])
} else {
*data, s.InputInterface = (*data)[4:], binary.BigEndian.Uint32((*data)[:4])
*data, s.OutputInterface = (*data)[4:], binary.BigEndian.Uint32((*data)[:4])
}
*data, s.RecordCount = (*data)[4:], binary.BigEndian.Uint32((*data)[:4])
for i := uint32(0); i < s.RecordCount; i++ {
rdf := SFlowFlowDataFormat(binary.BigEndian.Uint32((*data)[:4]))
_, flowRecordType := rdf.decode()
switch flowRecordType {
case SFlowTypeRawPacketFlow:
if record, err := decodeRawPacketFlowRecord(data); err == nil {
s.Records = append(s.Records, record)
} else {
return s, err
}
case SFlowTypeExtendedUserFlow:
if record, err := decodeExtendedUserFlow(data); err == nil {
s.Records = append(s.Records, record)
} else {
return s, err
}
case SFlowTypeExtendedUrlFlow:
if record, err := decodeExtendedURLRecord(data); err == nil {
s.Records = append(s.Records, record)
} else {
return s, err
}
case SFlowTypeExtendedSwitchFlow:
if record, err := decodeExtendedSwitchFlowRecord(data); err == nil {
s.Records = append(s.Records, record)
} else {
return s, err
}
case SFlowTypeExtendedRouterFlow:
if record, err := decodeExtendedRouterFlowRecord(data); err == nil {
s.Records = append(s.Records, record)
} else {
return s, err
}
case SFlowTypeExtendedGatewayFlow:
if record, err := decodeExtendedGatewayFlowRecord(data); err == nil {
s.Records = append(s.Records, record)
} else {
return s, err
}
case SFlowTypeEthernetFrameFlow:
// TODO
skipRecord(data)
return s, errors.New("skipping TypeEthernetFrameFlow")
case SFlowTypeIpv4Flow:
// TODO
skipRecord(data)
return s, errors.New("skipping TypeIpv4Flow")
case SFlowTypeIpv6Flow:
// TODO
skipRecord(data)
return s, errors.New("skipping TypeIpv6Flow")
case SFlowTypeExtendedMlpsFlow:
// TODO
skipRecord(data)
return s, errors.New("skipping TypeExtendedMlpsFlow")
case SFlowTypeExtendedNatFlow:
// TODO
skipRecord(data)
return s, errors.New("skipping TypeExtendedNatFlow")
case SFlowTypeExtendedMlpsTunnelFlow:
// TODO
skipRecord(data)
return s, errors.New("skipping TypeExtendedMlpsTunnelFlow")
case SFlowTypeExtendedMlpsVcFlow:
// TODO
skipRecord(data)
return s, errors.New("skipping TypeExtendedMlpsVcFlow")
case SFlowTypeExtendedMlpsFecFlow:
// TODO
skipRecord(data)
return s, errors.New("skipping TypeExtendedMlpsFecFlow")
case SFlowTypeExtendedMlpsLvpFecFlow:
// TODO
skipRecord(data)
return s, errors.New("skipping TypeExtendedMlpsLvpFecFlow")
case SFlowTypeExtendedVlanFlow:
// TODO
skipRecord(data)
return s, errors.New("skipping TypeExtendedVlanFlow")
default:
return s, fmt.Errorf("Unsupported flow record type: %d", flowRecordType)
}
}
return s, nil
}
// Counter samples report information about various counter
// objects. Typically these are items like IfInOctets, or
// CPU / Memory stats, etc. SFlow will report these at regular
// intervals as configured on the agent. If one were sufficiently
// industrious, this could be used to replace the typical
// SNMP polling used for such things.
type SFlowCounterSample struct {
EnterpriseID SFlowEnterpriseID
Format SFlowSampleType
SampleLength uint32
SequenceNumber uint32
SourceIDClass SFlowSourceFormat
SourceIDIndex SFlowSourceValue
RecordCount uint32
Records []SFlowRecord
}
// Counter samples have the following structure:
// 0 15 31
// +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+
// | int sample sequence number |
// +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+
// |id type | src id index value |
// +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+
// | int number of records |
// +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+
// / counter records /
// / /
// +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+
type SFlowCounterDataFormat uint32
func (cdf SFlowCounterDataFormat) decode() (SFlowEnterpriseID, SFlowCounterRecordType) {
leftField := cdf >> 12
rightField := uint32(0xFFF) & uint32(cdf)
return SFlowEnterpriseID(leftField), SFlowCounterRecordType(rightField)
}
// GetRecords will return a slice of interface types
// representing records. A type switch can be used to
// get at the underlying SFlowCounterRecordType.
func (cs SFlowCounterSample) GetRecords() []SFlowRecord {
return cs.Records
}
// GetType will report the type of sample. Only the
// compact form of counter samples is supported
func (cs SFlowCounterSample) GetType() SFlowSampleType {
return SFlowTypeCounterSample
}
type SFlowCounterRecordType uint32
const (
SFlowTypeGenericInterfaceCounters SFlowCounterRecordType = 1
SFlowTypeEthernetInterfaceCounters SFlowCounterRecordType = 2
SFlowTypeTokenRingInterfaceCounters SFlowCounterRecordType = 3
SFlowType100BaseVGInterfaceCounters SFlowCounterRecordType = 4
SFlowTypeVLANCounters SFlowCounterRecordType = 5
SFlowTypeProcessorCounters SFlowCounterRecordType = 1001
)
func (cr SFlowCounterRecordType) String() string {
switch cr {
case SFlowTypeGenericInterfaceCounters:
return "Generic Interface Counters"
case SFlowTypeEthernetInterfaceCounters:
return "Ethernet Interface Counters"
case SFlowTypeTokenRingInterfaceCounters:
return "Token Ring Interface Counters"
case SFlowType100BaseVGInterfaceCounters:
return "100BaseVG Interface Counters"
case SFlowTypeVLANCounters:
return "VLAN Counters"
case SFlowTypeProcessorCounters:
return "Processor Counters"
default:
return ""
}
}
func decodeCounterSample(data *[]byte, expanded bool) (SFlowCounterSample, error) {
s := SFlowCounterSample{}
var sdc SFlowDataSource
var sdce SFlowDataSourceExpanded
var sdf SFlowDataFormat
*data, sdf = (*data)[4:], SFlowDataFormat(binary.BigEndian.Uint32((*data)[:4]))
s.EnterpriseID, s.Format = sdf.decode()
*data, s.SampleLength = (*data)[4:], binary.BigEndian.Uint32((*data)[:4])
*data, s.SequenceNumber = (*data)[4:], binary.BigEndian.Uint32((*data)[:4])
if expanded {
*data, sdce = (*data)[8:], SFlowDataSourceExpanded{SFlowSourceFormat(binary.BigEndian.Uint32((*data)[:4])), SFlowSourceValue(binary.BigEndian.Uint32((*data)[4:8]))}
s.SourceIDClass, s.SourceIDIndex = sdce.decode()
} else {
*data, sdc = (*data)[4:], SFlowDataSource(binary.BigEndian.Uint32((*data)[:4]))
s.SourceIDClass, s.SourceIDIndex = sdc.decode()
}
*data, s.RecordCount = (*data)[4:], binary.BigEndian.Uint32((*data)[:4])
for i := uint32(0); i < s.RecordCount; i++ {
cdf := SFlowCounterDataFormat(binary.BigEndian.Uint32((*data)[:4]))
_, counterRecordType := cdf.decode()
switch counterRecordType {
case SFlowTypeGenericInterfaceCounters:
if record, err := decodeGenericInterfaceCounters(data); err == nil {
s.Records = append(s.Records, record)
} else {
return s, err
}
case SFlowTypeEthernetInterfaceCounters:
if record, err := decodeEthernetCounters(data); err == nil {
s.Records = append(s.Records, record)
} else {
return s, err
}
case SFlowTypeTokenRingInterfaceCounters:
skipRecord(data)
return s, errors.New("skipping TypeTokenRingInterfaceCounters")
case SFlowType100BaseVGInterfaceCounters:
skipRecord(data)
return s, errors.New("skipping Type100BaseVGInterfaceCounters")
case SFlowTypeVLANCounters:
skipRecord(data)
return s, errors.New("skipping TypeVLANCounters")
case SFlowTypeProcessorCounters:
if record, err := decodeProcessorCounters(data); err == nil {
s.Records = append(s.Records, record)
} else {
return s, err
}
default:
return s, fmt.Errorf("Invalid counter record type: %d", counterRecordType)
}
}
return s, nil
}
// SFlowBaseFlowRecord holds the fields common to all records
// of type SFlowFlowRecordType
type SFlowBaseFlowRecord struct {
EnterpriseID SFlowEnterpriseID
Format SFlowFlowRecordType
FlowDataLength uint32
}
func (bfr SFlowBaseFlowRecord) GetType() SFlowFlowRecordType {
return bfr.Format
}
// SFlowFlowRecordType denotes what kind of Flow Record is
// represented. See RFC 3176
type SFlowFlowRecordType uint32
const (
SFlowTypeRawPacketFlow SFlowFlowRecordType = 1
SFlowTypeEthernetFrameFlow SFlowFlowRecordType = 2
SFlowTypeIpv4Flow SFlowFlowRecordType = 3
SFlowTypeIpv6Flow SFlowFlowRecordType = 4
SFlowTypeExtendedSwitchFlow SFlowFlowRecordType = 1001
SFlowTypeExtendedRouterFlow SFlowFlowRecordType = 1002
SFlowTypeExtendedGatewayFlow SFlowFlowRecordType = 1003
SFlowTypeExtendedUserFlow SFlowFlowRecordType = 1004
SFlowTypeExtendedUrlFlow SFlowFlowRecordType = 1005
SFlowTypeExtendedMlpsFlow SFlowFlowRecordType = 1006
SFlowTypeExtendedNatFlow SFlowFlowRecordType = 1007
SFlowTypeExtendedMlpsTunnelFlow SFlowFlowRecordType = 1008
SFlowTypeExtendedMlpsVcFlow SFlowFlowRecordType = 1009
SFlowTypeExtendedMlpsFecFlow SFlowFlowRecordType = 1010
SFlowTypeExtendedMlpsLvpFecFlow SFlowFlowRecordType = 1011
SFlowTypeExtendedVlanFlow SFlowFlowRecordType = 1012
)
func (rt SFlowFlowRecordType) String() string {
switch rt {
case SFlowTypeRawPacketFlow:
return "Raw Packet Flow Record"
case SFlowTypeEthernetFrameFlow:
return "Ethernet Frame Flow Record"
case SFlowTypeIpv4Flow:
return "IPv4 Flow Record"
case SFlowTypeIpv6Flow:
return "IPv6 Flow Record"
case SFlowTypeExtendedSwitchFlow:
return "Extended Switch Flow Record"
case SFlowTypeExtendedRouterFlow:
return "Extended Router Flow Record"
case SFlowTypeExtendedGatewayFlow:
return "Extended Gateway Flow Record"
case SFlowTypeExtendedUserFlow:
return "Extended User Flow Record"
case SFlowTypeExtendedUrlFlow:
return "Extended URL Flow Record"
case SFlowTypeExtendedMlpsFlow:
return "Extended MPLS Flow Record"
case SFlowTypeExtendedNatFlow:
return "Extended NAT Flow Record"
case SFlowTypeExtendedMlpsTunnelFlow:
return "Extended MPLS Tunnel Flow Record"
case SFlowTypeExtendedMlpsVcFlow:
return "Extended MPLS VC Flow Record"
case SFlowTypeExtendedMlpsFecFlow:
return "Extended MPLS FEC Flow Record"
case SFlowTypeExtendedMlpsLvpFecFlow:
return "Extended MPLS LVP FEC Flow Record"
case SFlowTypeExtendedVlanFlow:
return "Extended VLAN Flow Record"
default:
return ""
}
}
// SFlowRawPacketFlowRecords hold information about a sampled
// packet grabbed as it transited the agent. This is
// perhaps the most useful and interesting record type,
// as it holds the headers of the sampled packet and
// can be used to build up a complete picture of the
// traffic patterns on a network.
//
// The raw packet header is sent back into gopacket for
// decoding, and the resulting gopackt.Packet is stored
// in the Header member
type SFlowRawPacketFlowRecord struct {
SFlowBaseFlowRecord
HeaderProtocol SFlowRawHeaderProtocol
FrameLength uint32
PayloadRemoved uint32
HeaderLength uint32
Header gopacket.Packet
}
// Raw packet record types have the following structure:
// 0 15 31
// +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+
// | 20 bit Interprise (0) |12 bit format |
// +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+
// | record length |
// +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+
// | Header Protocol |
// +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+
// | Frame Length |
// +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+
// | Payload Removed |
// +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+
// | Header Length |
// +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+
// \ Header \
// \ \
// \ \
// +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+
type SFlowRawHeaderProtocol uint32
const (
SFlowProtoEthernet SFlowRawHeaderProtocol = 1
SFlowProtoISO88024 SFlowRawHeaderProtocol = 2
SFlowProtoISO88025 SFlowRawHeaderProtocol = 3
SFlowProtoFDDI SFlowRawHeaderProtocol = 4
SFlowProtoFrameRelay SFlowRawHeaderProtocol = 5
SFlowProtoX25 SFlowRawHeaderProtocol = 6
SFlowProtoPPP SFlowRawHeaderProtocol = 7
SFlowProtoSMDS SFlowRawHeaderProtocol = 8
SFlowProtoAAL5 SFlowRawHeaderProtocol = 9
SFlowProtoAAL5_IP SFlowRawHeaderProtocol = 10 /* e.g. Cisco AAL5 mux */
SFlowProtoIPv4 SFlowRawHeaderProtocol = 11
SFlowProtoIPv6 SFlowRawHeaderProtocol = 12
SFlowProtoMPLS SFlowRawHeaderProtocol = 13
SFlowProtoPOS SFlowRawHeaderProtocol = 14 /* RFC 1662, 2615 */
)
func (sfhp SFlowRawHeaderProtocol) String() string {
switch sfhp {
case SFlowProtoEthernet:
return "ETHERNET-ISO88023"
case SFlowProtoISO88024:
return "ISO88024-TOKENBUS"
case SFlowProtoISO88025:
return "ISO88025-TOKENRING"
case SFlowProtoFDDI:
return "FDDI"
case SFlowProtoFrameRelay:
return "FRAME-RELAY"
case SFlowProtoX25:
return "X25"
case SFlowProtoPPP:
return "PPP"
case SFlowProtoSMDS:
return "SMDS"
case SFlowProtoAAL5:
return "AAL5"
case SFlowProtoAAL5_IP:
return "AAL5-IP"
case SFlowProtoIPv4:
return "IPv4"
case SFlowProtoIPv6:
return "IPv6"
case SFlowProtoMPLS:
return "MPLS"
case SFlowProtoPOS:
return "POS"
}
return "UNKNOWN"
}
func decodeRawPacketFlowRecord(data *[]byte) (SFlowRawPacketFlowRecord, error) {
rec := SFlowRawPacketFlowRecord{}
header := []byte{}
var fdf SFlowFlowDataFormat
*data, fdf = (*data)[4:], SFlowFlowDataFormat(binary.BigEndian.Uint32((*data)[:4]))
rec.EnterpriseID, rec.Format = fdf.decode()
*data, rec.FlowDataLength = (*data)[4:], binary.BigEndian.Uint32((*data)[:4])
*data, rec.HeaderProtocol = (*data)[4:], SFlowRawHeaderProtocol(binary.BigEndian.Uint32((*data)[:4]))
*data, rec.FrameLength = (*data)[4:], binary.BigEndian.Uint32((*data)[:4])
*data, rec.PayloadRemoved = (*data)[4:], binary.BigEndian.Uint32((*data)[:4])
*data, rec.HeaderLength = (*data)[4:], binary.BigEndian.Uint32((*data)[:4])
headerLenWithPadding := int(rec.HeaderLength + ((4 - rec.HeaderLength) % 4))
*data, header = (*data)[headerLenWithPadding:], (*data)[:headerLenWithPadding]
rec.Header = gopacket.NewPacket(header, LayerTypeEthernet, gopacket.Default)
return rec, nil
}
// SFlowExtendedSwitchFlowRecord give additional information
// about the sampled packet if it's available. It's mainly
// useful for getting at the incoming and outgoing VLANs
// An agent may or may not provide this information.
type SFlowExtendedSwitchFlowRecord struct {
SFlowBaseFlowRecord
IncomingVLAN uint32
IncomingVLANPriority uint32
OutgoingVLAN uint32
OutgoingVLANPriority uint32
}
// Extended switch records have the following structure:
// 0 15 31
// +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+
// | 20 bit Interprise (0) |12 bit format |
// +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+
// | record length |
// +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+
// | Incoming VLAN |
// +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+
// | Incoming VLAN Priority |
// +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+
// | Outgoing VLAN |
// +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+
// | Outgoing VLAN Priority |
// +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+
func decodeExtendedSwitchFlowRecord(data *[]byte) (SFlowExtendedSwitchFlowRecord, error) {
es := SFlowExtendedSwitchFlowRecord{}
var fdf SFlowFlowDataFormat
*data, fdf = (*data)[4:], SFlowFlowDataFormat(binary.BigEndian.Uint32((*data)[:4]))
es.EnterpriseID, es.Format = fdf.decode()
*data, es.FlowDataLength = (*data)[4:], binary.BigEndian.Uint32((*data)[:4])
*data, es.IncomingVLAN = (*data)[4:], binary.BigEndian.Uint32((*data)[:4])
*data, es.IncomingVLANPriority = (*data)[4:], binary.BigEndian.Uint32((*data)[:4])
*data, es.OutgoingVLAN = (*data)[4:], binary.BigEndian.Uint32((*data)[:4])
*data, es.OutgoingVLANPriority = (*data)[4:], binary.BigEndian.Uint32((*data)[:4])
return es, nil
}
// SFlowExtendedRouterFlowRecord gives additional information
// about the layer 3 routing information used to forward
// the packet
type SFlowExtendedRouterFlowRecord struct {
SFlowBaseFlowRecord
NextHop net.IP
NextHopSourceMask uint32
NextHopDestinationMask uint32
}
// Extended router records have the following structure:
// 0 15 31
// +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+
// | 20 bit Interprise (0) |12 bit format |
// +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+
// | record length |
// +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+
// | Next Hop |
// +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+
// | Next Hop Source Mask |
// +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+
// | Next Hop Destination Mask |
// +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+
func decodeExtendedRouterFlowRecord(data *[]byte) (SFlowExtendedRouterFlowRecord, error) {
er := SFlowExtendedRouterFlowRecord{}
var fdf SFlowFlowDataFormat
*data, fdf = (*data)[4:], SFlowFlowDataFormat(binary.BigEndian.Uint32((*data)[:4]))
er.EnterpriseID, er.Format = fdf.decode()
*data, er.FlowDataLength = (*data)[4:], binary.BigEndian.Uint32((*data)[:4])
*data, er.NextHop = (*data)[4:], (*data)[:4]
*data, er.NextHopSourceMask = (*data)[4:], binary.BigEndian.Uint32((*data)[:4])
*data, er.NextHopDestinationMask = (*data)[4:], binary.BigEndian.Uint32((*data)[:4])
return er, nil
}
// SFlowExtendedGatewayFlowRecord describes information treasured by
// nework engineers everywhere: AS path information listing which
// BGP peer sent the packet, and various other BGP related info.
// This information is vital because it gives a picture of how much
// traffic is being sent from / received by various BGP peers.
// Extended gatway records have the following structure:
// 0 15 31
// +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+
// | 20 bit Interprise (0) |12 bit format |
// +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+
// | record length |
// +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+
// | Next Hop |
// +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+
// | AS |
// +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+
// | Source AS |
// +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+