flowclass/flowclass.go

package flowclass

import (
	"fmt"

	"idio.link/go/netaddr/v2"
	"idio.link/go/parser"
)

type FlowClass struct {
	// dstClasses indices correspond to ipps indices
	tree *parser.CSTNode
	srcs []*netaddr.NetAddr
	dsts [][]*netaddr.NetAddr
	ipps [][]IPP
}

func (fc *FlowClass) Compile(s string) error {
	err := fc.tree.Parse(s)
	if err != nil {
		return err
	}
	coalesced := fc.tree.Coalesce()
	fc.srcs = coalesced.srcs.(map[string]*netaddr.NetAddr)
	fc.dsts = coalesced.dsts.([]*DstSock)
	fc.tree = nil
	return nil
}

func (fc *FlowClass) Sources() []*netaddr.NetAddr {
	srcs := make([]*netaddr.NetAddr, len(fc.srcs))
	for i, e := range fc.srcs {
		tmp := *e
		srcs[i] = &tmp
	}
	return srcs
}

func (fc *FlowClass) Destinations() []*netaddr.NetAddr {
	dsts := make([]*netaddr.NetAddr, len(fc.dsts))
	for i, e := range fc.dstSocks {
		tmp := *e
		dsts[i] = &tmp
	}
	return dsts
}

type IPP interface {
	Name() string
	Decimal() ipProtocol
	String() string
}

/* If this is used to indicate ICMP with type of "any", how
 * do we represent this in port literals?
 */
type ipProtocol byte

func (p ipProtocol) Name() string {
	return ""
}

func (p ipProtocol) String() string {
	return fmt.Sprintf("%d", p)
}

func (p ipProtocol) Decimal() ipProtocol {
	return p
}

type ippICMP struct {
	icmpType byte
	code     byte
}

func (p ippICMP) Type() byte {
	return p.icmpType
}

func (p ippICMP) Code() byte {
	return p.code
}

func (p ippICMP) Name() string {
	return "icmp"
}

func (p ippICMP) Decimal() ipProtocol {
	return 1
}

func (p ippICMP) String() string {
	return fmt.Sprintf("%s(%d,%d)", p.Name(), p.Type(), p.Code())
}

type ippTCP struct {
	spt uint16
	dpt uint16
}

func (p ippTCP) Sport() uint16 {
	return p.spt
}

func (p ippTCP) Dport() uint16 {
	return p.dpt
}

func (p ippTCP) Name() string {
	return "tcp"
}

func (p ippTCP) Decimal() ipProtocol {
	return 6
}

func (p ippTCP) String() string {
	return fmt.Sprintf("%s(%d,%d)", p.Name(), p.Sport(), p.Dport())
}

type ippUDP struct {
	spt uint16
	dpt uint16
}

func (p ippUDP) Sport() uint16 {
	return p.spt
}

func (p ippUDP) Dport() uint16 {
	return p.dpt
}

func (p ippUDP) Name() string {
	return "udp"
}

func (p ippUDP) Decimal() ipProtocol {
	return 17
}

func (p ippUDP) String() string {
	return fmt.Sprintf("%s(%d,%d)", p.Name(), p.Sport(), p.Dport())
}