func (_ requestRebindState) do(ctx *dhcpContext) iState {
ipAddr := ctx.IpAddr.Load().(net.IP)
// Set up all the layers' fields we can.
eth := &layers.Ethernet{
SrcMAC: ctx.MacAddr,
DstMAC: arp.HwAddrBcast,
EthernetType: layers.EthernetTypeIPv4,
}
ipv4 := &layers.IPv4{
Version: 4,
TTL: 255,
Protocol: layers.IPProtocolUDP,
SrcIP: net.IPv4zero,
DstIP: net.IPv4bcast,
}
udp := &layers.UDP{
SrcPort: network.Bootpc,
DstPort: network.Bootps,
}
udp.SetNetworkLayerForChecksum(ipv4)
buf := network.GetBuffer()
defer network.ReleaseBuffer(buf)
request := new(dhcpv4.DhcpPacket)
request.ConstructWithPreAllocatedBuffer(buf, option.DHCPREQUEST)
request.SetXid(ctx.xid[:])
request.SetMacAddr(ctx.MacAddr)
opt50 := new(option.Option50RequestedIpAddress)
opt50.Construct(util.Convert4byteToUint32(ipAddr))
request.AddOption(opt50)
opt61 := new(option.Option61ClientIdentifier)
opt61.Construct(byte(1), ctx.MacAddr)
request.AddOption(opt61)
if DhcRelay {
request.SetGiAddr(ctx.giaddr)
request.AddOption(generateOption82(ctx.MacAddr))
}
if Option90 {
request.AddOption(generateOption90(ctx.login))
}
bootp := &layer.PayloadLayer{
Contents: request.Raw,
}
for {
// send request
for err := network.SentPacket(eth, ipv4, udp, bootp); err != nil; {
log.Println(ctx.MacAddr, "REBIND: error sending request", err)
time.Sleep(2 * time.Second)
}
var (
payload []byte
timeout time.Duration
deadline = time.Now().Add(2 * time.Second)
)
for {
timeout = deadline.Sub(time.Now())
select {
case <-time.After(timeout):
log.Println(ctx.MacAddr, "REBIND: timeout")
return timeoutRebindState{}
case payload = <-ctx.dhcpIn:
dp, err := dhcpv4.Parse(payload)
if err != nil {
// it is not DHCP packet...
continue
}
if !bytes.Equal(ctx.xid[:], dp.GetXid()) {
// bug of DHCP Server ?
log.Println(ctx.MacAddr, fmt.Sprintf("REBIND: unexpected xid [Expected: 0x%v] [Actual: 0x%v]", hex.EncodeToString(ctx.xid[:]), hex.EncodeToString(dp.GetXid())))
continue
}
if msgType, err := dp.GetTypeMessage(); err == nil {
switch msgType {
case option.DHCPACK:
ctx.t0, ctx.t1, ctx.t2 = extractAllLeaseTime(dp)
return sleepState{}
case option.DHCPNAK:
log.Println(ctx.MacAddr, "REBIND: receive NAK")
return discoverState{}
default:
log.Println(ctx.MacAddr, fmt.Sprintf("REBIND: unexpected message [Excpected: %s] [Actual: %s]", option.DHCPACK, msgType))
continue
}
} else {
log.Println(ctx.MacAddr, "REBIND: option 53 is missing")
continue
}
}
}
}
}
func fuzzParse(data []byte) (int, *DhcpPacket, option.SpecificOption) {
var o option.SpecificOption
p, err := Parse(data)
if err != nil {
if p != nil {
panic("packet != nil on error")
}
return 0, nil, o
}
if p == nil {
panic("packet == nil when no error")
}
if !p.ContainsMagicCookie() {
panic("No magic Cookie...")
}
if p.GetMacAddr() == nil {
panic("MacAddr is nil")
}
if len(p.GetMacAddr()) > 16 {
panic("MacAddr is greater than 16")
}
{ // option 53
opt := new(option.Option53MessageType)
if f, e := p.GetOption(opt); e == nil {
if f {
if opt.GetLength() != 1 {
panic("len opt53 != 1")
}
if len(opt.GetValue()) != int(opt.GetLength()) {
panic("len opt53 inconsistency")
}
o = opt
}
}
}
{ // option 51 and all TypeUint32 option type (e.g. option 54, option 58, option 59 ...)
opt := new(option.Option51IpAddressLeaseTime)
if f, e := p.GetOption(opt); e == nil {
if f {
if opt.GetLength() != 4 {
panic("len opt51 != 4")
}
if len(opt.GetValue()) != int(opt.GetLength()) {
panic("len opt51 inconsistency")
}
o = opt
}
}
}
{ // option 82
opt := new(option.Option82DhcpAgentOption)
if f, e := p.GetOption(opt); e == nil {
if f {
if len(opt.GetValue()) != int(opt.GetLength()) {
panic("len opt82 inconsistency")
}
{ // option 82.1
ssOpt := new(option.Option82_1CircuitId)
opt.GetSubOptions(ssOpt)
}
{ // option 82.2
ssOpt := new(option.Option82_2RemoteId)
opt.GetSubOptions(ssOpt)
}
{ // option 82.9
ssOpt := new(option.Option82_9VendorSpecificInformation)
_, _ = opt.GetSubOptions(ssOpt)
}
o = opt
}
}
}
{ // option 60 and all TypeString option type (option 15 ...)
opt := new(option.Option60VendorClassIdentifier)
if f, e := p.GetOption(opt); e == nil {
if f {
if len(opt.GetString()) != int(opt.GetLength()) {
panic("len opt60 inconsistency")
}
}
}
}
{ // option 6 and all TypeListUint32 option type (option 10, option 11 ...)
opt := new(option.Option6DomainNameServerOption)
if f, e := p.GetOption(opt); e == nil {
if f {
if len(opt.GetValue()) != int(opt.GetLength()) {
panic("len opt6 inconsistency")
}
}
}
}
{ // option 119
opt := new(option.Option119DomainSearch)
if f, e := p.GetOption(opt); e == nil {
if f {
_ = opt.GetSearchString()
}
}
}
{ // option 120
opt := new(option.Option120SipServers)
if f, e := p.GetOption(opt); e == nil {
if f {
switch opt.GetEnc() {
case option.ENC_FQDN:
fqdns, e := opt.GetFqdnList()
if e != nil && fqdns != nil {
panic("opt120 ENC_FQDN fqdns != nil on error")
}
case option.ENC_IP:
addrs, e := opt.GetIpAddresses()
if e != nil && addrs != nil {
panic("opt120 ENC_IP addrs != nil on error")
}
default:
panic("opt120 with ENC_UNKNOWN is not possible to have error == nil on p.GetOption(opt)")
}
}
}
}
{ // option 119
opt := new(option.Option119DomainSearch)
if f, e := p.GetOption(opt); e == nil {
if f {
_ = opt.GetSearchString()
}
}
}
{ // option 61
opt := new(option.Option61ClientIdentifier)
if f, e := p.GetOption(opt); e == nil {
if f {
_ = opt.GetClientIdentifier()
}
}
}
{ // option 77
opt := new(option.Option77UserClass)
if f, e := p.GetOption(opt); e == nil {
if f {
if len(opt.GetValue()) != int(opt.GetLength()) {
panic("len opt77 inconsistency")
}
for _, uc := range opt.UserClassDatas {
if len(uc.GetUcData()) != int(uc.GetUcLen()) {
panic("opt77 UserClass len inconsistency")
}
}
}
}
}
{ // option 90
opt := new(option.Option90Authentificiation)
if f, e := p.GetOption(opt); e == nil {
if f {
opt.GetProtocol()
opt.GetAlgorithm()
opt.GetRdm()
opt.GetReplayDetection()
opt.GetAuthenticationInformation()
}
}
}
{ // option 121
opt := new(option.Option121ClasslessStaticRoute)
p.GetOption(opt)
}
return 1, p, o
}