diag

README

diag

This is a work in progress version of diag. It provides a C-binding free API to the netlink based socket statistics system.

Example

package main

import (
	"fmt"
	"os"

	"github.com/florianl/go-diag"
)

func main() {
	// open a netlink socket
	nl, err := diag.Open(&diag.Config{})
	if err != nil {
		fmt.Fprintf(os.Stderr, "could not open netlink socket: %v\n", err)
		return
	}
	defer nl.Close()

	// Dump all TCP sockets
	tcpSockets, err := nl.TCP().Dump()
	if err != nil {
		fmt.Fprintf(os.Stderr, "could not dump data: %v\n", err)
		return
	}

    // Loop over tcpSockets and print out source- and destination IP with
    // the respective port information.
	for _, socket := range tcpSockets {
		src := diag.ToNetipAddr(socket.ID.Src)
		srcPort := diag.Ntohs(socket.ID.SPort)
		dst := diag.ToNetipAddr(socket.ID.Dst)
		dstPort := diag.Ntohs(socket.ID.DPort)
		fmt.Printf("%v:%d -> %v:%d\n", src, srcPort, dst, dstPort)
	}
}

Requirements

• A version of Go that is supported by upstream

Documentation

Index

• func Ntohs(in uint16) uint16
• func ToNetipAddr(in [4]uint32) netip.Addr
• type Attribute
• type BBRInfo
• type Config
• type DCTCPInfo
• type Diag
  • func Open(config *Config) (*Diag, error)
  • func (d *Diag) Close() error
  • func (d *Diag) Raw() *Raw
  • func (d *Diag) SetOption(o netlink.ConnOption, enable bool) error
  • func (d *Diag) TCP() *TCP
  • func (d *Diag) UDP() *UDP
• type DiagMsg
• type InetDiagReqV2
• type MemInfo
• type Object
• type Raw
  • func (r *Raw) Dump() ([]Object, error)
• type SockID
• type SockOpt
• type TCP
  • func (t *TCP) Dump() ([]Object, error)
• type UDP
  • func (u *UDP) Dump() ([]Object, error)
• type VegasInfo

Functions

func Ntohs

func Ntohs(in uint16) uint16

Ntohs converts in from network byte order to host byte order represenation.

func ToNetipAddr

func ToNetipAddr(in [4]uint32) netip.Addr

ToNetipAddr converts an IP in [4]uint32 representation to netip.Addr.

Types

type Attribute

type Attribute struct {
	MemInfo   *MemInfo
	VegasInfo *VegasInfo
	Cong      *string
	TOS       *uint8
	TClass    *uint8
	Shutdown  *uint8
	DCTCPInfo *DCTCPInfo
	Protocol  *uint8
	SKV6Only  *uint8
	Mark      *uint32
	BBRInfo   *BBRInfo
	ClassID   *uint32
	CGroupID  *uint64
	SockOpt   *SockOpt
}

Attribute contains various elements

type BBRInfo

type BBRInfo struct {
	BwLo       uint32
	BwHi       uint32
	MinRTT     uint32
	PacingGain uint32
	CwndGaing  uint32
}

Based on tcp_bbr_info

type Config

type Config struct {
	// NetNS defines the network namespace
	NetNS int
}

Config contains options for NETLINK_SOCK_DIAG

type DCTCPInfo

type DCTCPInfo struct {
	Enabeld uint16
	CeState uint16
	Alpha   uint32
	AbECN   uint32
	AbTot   uint32
}

Based on tcp_dctcp_info

type Diag

type Diag struct {
	// contains filtered or unexported fields
}

Diag represents a netlink wrapper

func Open

func Open(config *Config) (*Diag, error)

Open establishes a netlink socket for traffic control

func (*Diag) Close

func (d *Diag) Close() error

Close the connection

func (*Diag) Raw

func (d *Diag) Raw() *Raw

Raw allows to read and alter Raw socker information.

func (*Diag) SetOption

func (d *Diag) SetOption(o netlink.ConnOption, enable bool) error

SetOption allows to enable or disable netlink socket options.

func (*Diag) TCP

func (d *Diag) TCP() *TCP

TCP allows to read and alter TCP socker information.

func (*Diag) UDP

func (d *Diag) UDP() *UDP

UDP allows to read and alter UDP socker information.

type DiagMsg

type DiagMsg struct {
	Famiy   uint8
	State   uint8
	Timer   uint8
	Retrans uint8
	ID      SockID
	Expires uint32
	RQueue  uint32
	WQueue  uint32
	UID     uint32
	INode   uint32
}

Based on inet_diag_msg

type InetDiagReqV2

type InetDiagReqV2 struct {
	Family   uint8
	Protocol uint8
	Ext      uint8
	Pad      uint8
	States   uint32
	ID       SockID
}

Based on inet_diag_req_v2

type MemInfo

type MemInfo struct {
	RMem uint32
	WMem uint32
	FMem uint32
	TMem uint32
}

Based on inet_diag_meminfo

type Object

type Object struct {
	DiagMsg
	Attribute
}

Object represents a generic object

type Raw

type Raw struct {
	Diag
}

func (*Raw) Dump

func (r *Raw) Dump() ([]Object, error)

type SockID

type SockID struct {
	SPort  uint16    // in network byte order, use Ntohs() for host byte order
	DPort  uint16    // in network byte order, use Ntohs() for host byte order
	Src    [4]uint32 // use ToNetipAddr() for netip.Addr representation
	Dst    [4]uint32 // use ToNetipAddr() for netip.Addr representation
	If     uint32
	Cookie [2]uint32
}

Based on inet_diag_sockid

type SockOpt

type SockOpt struct {
	Bitfield1 uint8
	Bitfield2 uint8
}

Based on inet_diag_sockopt Bitfield1 and Bitfield2 are the Go representations for the following bit fields:

__u8  recverr:1,
      is_icsk:1,
      freebind:1,
      hdrincl:1,
      mc_loop:1,
      transparent:1,
      mc_all:1,
      nodefrag:1;
__u8  bind_address_no_port:1,
      recverr_rfc4884:1,
      defer_connect:1,
      unused:5;

type TCP

type TCP struct {
	Diag
}

func (*TCP) Dump

func (t *TCP) Dump() ([]Object, error)

type UDP

type UDP struct {
	Diag
}

func (*UDP) Dump

func (u *UDP) Dump() ([]Object, error)

type VegasInfo

type VegasInfo struct {
	Enabled uint32
	RttCnt  uint32
	Rtt     uint32
	MinRtt  uint32
}

Based on tcpvegas_info