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|
package main
import (
"fmt"
// "log"
"github.com/insomniacslk/dhcp/dhcpv6"
)
// FSM from RFC 2131 Figure 5
type DHCP interface {
SendDiscover()
SendRequest()
}
type FSM struct {
state State
dhcp DHCP
}
type DHCPv4 struct {
}
func (f FSM) Init(d DHCP) {
fmt.Println("Init")
f.dhcp = d
f.state = stInit(f.dhcp, nil)
// go
}
func (f FSM) InputMessage() {
}
func (d DHCPv4) SendDiscover() {
}
type DHCPv6 struct {
}
func (d DHCPv6) SendDiscover() {
fmt.Println("SendDiscover")
}
func (d DHCPv6) SendRequest() {
fmt.Println("SendRequest")
}
type EventType uint8
const (
EventTypeNone EventType = 0
EventTypeMessage EventType = 1
EventTypeTimeoutT1 EventType = 2
EventTypeTimeoutT2 EventType = 3
EventTypeTimeoutLease EventType = 3
)
type Event interface {
Type() EventType
}
// type TimerType uint8
// const (
// TimerNone TimerType = 0
// TimerT1 TimerType = 1
// TimerT2 TimerType = 2
// TimerLease TimerType = 3
// )
// type EventTimeout struct {
// Event
// Timer TimerType
// }
type EventMessage struct {
Event
msg dhcpv6.Message
}
func (ev *EventMessage) Type() EventType {
return EventTypeMessage
}
func (ev *EventMessage) Msg() dhcpv6.Message {
return ev.msg
}
type State func (d DHCP, ev Event) (next State)
func stInit(d DHCP, ev Event) State {
// Send Discover
d.SendDiscover()
return stSelecting
}
func stSelecting(d DHCP, ev Event) State {
switch ev.Type() {
case EventTypeMessage:
msg := ev.(*EventMessage).Msg()
switch msg.Type() {
case dhcpv6.MessageTypeAdvertise:
// Select first offer
d.SendRequest()
return stRequesting
}
}
return stSelecting
}
func stRequesting(d DHCP, ev Event) State {
switch ev.Type() {
case EventTypeMessage:
msg := ev.(*EventMessage).Msg()
switch msg.Type() {
case dhcpv6.MessageTypeAdvertise:
// Discard
return stRequesting
case dhcpv6.MessageTypeReply:
// Record lease, set T1, T2
return stBound
case dhcpv6.MessageTypeNone: // FIXME NAK
// Send Decline
return stInit
}
}
return stRequesting
}
func stBound(d DHCP, ev Event) State {
switch ev.Type() {
case EventTypeTimeoutT1:
// Send Request
return stRenewing
case EventTypeMessage:
msg := ev.(*EventMessage).Msg()
switch msg.Type() {
case dhcpv6.MessageTypeAdvertise:
case dhcpv6.MessageTypeReply:
case dhcpv6.MessageTypeNone:
// TODO or NACK
// Send Decline
return stBound
}
}
return stBound
}
func stRenewing(d DHCP, ev Event) State {
// FIXME
switch ev.Type() {
case EventTypeTimeoutT2:
// Broadcast request?
return stRebinding
case EventTypeMessage:
msg := ev.(*EventMessage).Msg()
switch msg.Type() {
case dhcpv6.MessageTypeReply:
// Record lease, set T1, T2
return stBound
case dhcpv6.MessageTypeNone: // FIXME NAK
// HALT network
return stInit
}
}
return stRenewing
}
func stRebinding(d DHCP, ev Event) State {
switch ev.Type() {
case EventTypeTimeoutLease:
// Halt network
return stInit
case EventTypeMessage:
msg := ev.(*EventMessage).Msg()
switch msg.Type() {
case dhcpv6.MessageTypeReply:
// Record lease, set timers T1, T2
return stBound
case dhcpv6.MessageTypeNone: // FIXME NAK
// Halt network
return stInit
}
}
return stRebinding
}
|
