nat

Documentation

Index

• Constants
• func ParsePorts(portsStr string) ([]int, error)
• type Destination
  • func NewDestination(proto string, ip net.IP, ports []int) (Destination, error)
  • func (rk Destination) IP() net.IP
  • func (rk Destination) Ports() []int
  • func (rk Destination) Proto() string
  • func (rk Destination) String() string
• type FirewallRouter
  • func NewRouter(name string, localIPv4, localIPv6 net.IP) FirewallRouter
• type Route
  • func NewRoute(proto string, ip net.IP, ports []int, toPort int) (*Route, error)
  • func (e *Route) Equal(o *Route) bool
  • func (e *Route) String() string
• type Table

Constants

const SO_ORIGINAL_DST = 80

Functions

func ParsePorts

func ParsePorts(portsStr string) ([]int, error)

Types

type Destination

type Destination string

A Destination is an immutable value that is used as a key in the routing table and when sorting routes. The choice to use a single string was motivated by a desire to have a value that:

• can be ordered correctly (IPs or ports represented as a strings cannot)
• is compact and hence very efficient when lexically compared or when used as a hash key
• is immutable

func NewDestination

func NewDestination(proto string, ip net.IP, ports []int) (Destination, error)

NewDestination creates a new Destination. Valid protocols are "tcp" and "udp"

func (Destination) IP

func (rk Destination) IP() net.IP

IP Returns the IP-address

func (Destination) Ports

func (rk Destination) Ports() []int

Ports returns the ports, if any

func (Destination) Proto

func (rk Destination) Proto() string

Proto returns the protocol

func (Destination) String

func (rk Destination) String() string

String returns a string <proto>:<ip> and optionally a comma separated list of ports delimited by []

type FirewallRouter

type FirewallRouter interface {
	// Flush will flush any pending rule changes that needs to be committed
	Flush(ctx context.Context) error

	// Clear the given route. Returns true if the route was cleared and  false if no such route was found.
	Clear(ctx context.Context, route *Route) (bool, error)

	// Add the given route. If the route already exists and is different from the given route, it is
	// cleared before the new route is added. Returns true if the route was add and false if it was already present.
	Add(ctx context.Context, route *Route) (bool, error)

	// Disable the router.
	Disable(ctx context.Context) error

	// Enable the router
	Enable(ctx context.Context) error

	// Get the original destination for a connection that has been routed.
	GetOriginalDst(conn *net.TCPConn) (host string, err error)
}

FirewallRouter is an interface to what is essentially a routing table, but implemented in the firewall.

TODO(lukeshu): Why have we implemented the routing table in the firewall? Mostly historical reasons, and we should consider using the real routing table.

func NewRouter

func NewRouter(name string, localIPv4, localIPv6 net.IP) FirewallRouter

type Route

type Route struct {
	Destination
	ToPort int
}

func NewRoute

func NewRoute(proto string, ip net.IP, ports []int, toPort int) (*Route, error)

func (*Route) Equal

func (e *Route) Equal(o *Route) bool

func (*Route) String

func (e *Route) String() string

type Table

type Table struct {
	Name   string
	Routes []*Route
}