parser

Documentation

Overview

Package netlink contains the bare minimum needed to partially parse netlink messages.

Index

• Constants
• Variables
• func Parse(raw inetdiag.RawInetDiagMsg) (*inetdiag.InetDiagMsg, error)
• type NetlinkMessage
• type NetlinkRouteAttr
  • func ParseRouteAttr(b []byte) ([]NetlinkRouteAttr, error)
• type NlMsghdr
• type RouteAttrValue
  • func (raw RouteAttrValue) CongestionAlgorithm() (string, bool)
• type RtAttr
• type Snapshot
  • func MakeSnapShot(msg *NetlinkMessage, skipLocal bool) (*Snapshot, error)

Constants

const (
	RTA_ALIGNTO    = 4
	SizeofNlMsghdr = 0x10
	SizeofNlAttr   = 0x4
	SizeofRtAttr   = 0x4

	EINVAL = syscall.Errno(0x16)
)

TODO - get these from sys/unix or syscall

Variables

var (
	ErrNotType20   = errors.New("NetlinkMessage wrong type")
	ErrParseFailed = errors.New("Unable to parse InetDiagMsg")
)

Error types.

Functions

func Parse

func Parse(raw inetdiag.RawInetDiagMsg) (*inetdiag.InetDiagMsg, error)

Parse returns the InetDiagMsg itself Modified from original to also return attribute data array.

Types

type NetlinkMessage

type NetlinkMessage = syscall.NetlinkMessage

type NetlinkRouteAttr

type NetlinkRouteAttr = syscall.NetlinkRouteAttr

func ParseRouteAttr

func ParseRouteAttr(b []byte) ([]NetlinkRouteAttr, error)

ParseRouteAttr parses a byte array into slice of NetlinkRouteAttr struct. Derived from "github.com/vishvananda/netlink/nl/nl_linux.go"

type NlMsghdr

type NlMsghdr = syscall.NlMsghdr

TODO use unix instead.

type RouteAttrValue

type RouteAttrValue []byte

RouteAttrValue is the type of RouteAttr.Value

func (RouteAttrValue) CongestionAlgorithm

func (raw RouteAttrValue) CongestionAlgorithm() (string, bool)

CongestionAlgorithm returns the congestion algorithm string INET_DIAG_CONG

type RtAttr

type RtAttr = syscall.RtAttr

type Snapshot

type Snapshot struct {
	// Timestamp of batch of messages containing this message.
	Timestamp time.Time

	// Bit field indicating whether each message type was observed.
	Observed uint32

	// Bit field indicating whether any message type was NOT fully parsed.
	// TODO - populate this field if any message is ignored, or not fully parsed.
	NotFullyParsed uint32

	// Info from struct inet_diag_msg, including socket_id;
	InetDiagMsg *inetdiag.InetDiagMsg

	SockInfo *inetdiag.SockID
	// From INET_DIAG_CONG message.
	CongestionAlgorithm string

	// See https://tools.ietf.org/html/rfc3168
	// TODO Do we need to record whether these are present and zero, vs absent?
	TOS     uint8
	TClass  uint8
	ClassID uint8

	// TODO Do we need to record present and zero, vs absent?
	Shutdown uint8

	// From INET_DIAG_PROTOCOL message.
	// TODO Do we need to record present and zero, vs absent?
	Protocol inetdiag.Protocol

	Mark uint32

	// TCPInfo contains data from struct tcp_info.
	TCPInfo *tcp.LinuxTCPInfo

	// Data obtained from INET_DIAG_MEMINFO.
	MemInfo *inetdiag.MemInfo

	// Data obtained from INET_DIAG_SKMEMINFO.
	SocketMem *inetdiag.SocketMemInfo

	VegasInfo *inetdiag.VegasInfo
	DCTCPInfo *inetdiag.DCTCPInfo
	BBRInfo   *inetdiag.BBRInfo
}

Snapshot contains all info gathered through netlink library.

func MakeSnapShot

func MakeSnapShot(msg *NetlinkMessage, skipLocal bool) (*Snapshot, error)

MakeArchivalRecord parses the NetlinkMessage into a ArchivalRecord. If skipLocal is true, it will return nil for loopback, local unicast, multicast, and unspecified connections. Note that Parse does not populate the Timestamp field, so caller should do so.