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package dhcpv6
import (
"fmt"
"net"
"github.com/insomniacslk/dhcp/rfc1035label"
"github.com/u-root/uio/uio"
)
// NTPSuboptionSrvAddr is NTP_SUBOPTION_SRV_ADDR according to RFC 5908.
type NTPSuboptionSrvAddr net.IP
// Code returns the suboption code.
func (n *NTPSuboptionSrvAddr) Code() OptionCode {
return NTPSuboptionSrvAddrCode
}
// ToBytes returns the byte serialization of the suboption.
func (n *NTPSuboptionSrvAddr) ToBytes() []byte {
buf := uio.NewBigEndianBuffer(nil)
buf.Write16(uint16(NTPSuboptionSrvAddrCode))
buf.Write16(uint16(net.IPv6len))
buf.WriteBytes(net.IP(*n).To16())
return buf.Data()
}
func (n *NTPSuboptionSrvAddr) String() string {
return fmt.Sprintf("Server Address: %s", net.IP(*n).String())
}
// NTPSuboptionMCAddr is NTP_SUBOPTION_MC_ADDR according to RFC 5908.
type NTPSuboptionMCAddr net.IP
// Code returns the suboption code.
func (n *NTPSuboptionMCAddr) Code() OptionCode {
return NTPSuboptionMCAddrCode
}
// ToBytes returns the byte serialization of the suboption.
func (n *NTPSuboptionMCAddr) ToBytes() []byte {
buf := uio.NewBigEndianBuffer(nil)
buf.Write16(uint16(NTPSuboptionMCAddrCode))
buf.Write16(uint16(net.IPv6len))
buf.WriteBytes(net.IP(*n).To16())
return buf.Data()
}
func (n *NTPSuboptionMCAddr) String() string {
return fmt.Sprintf("Multicast Address: %s", net.IP(*n).String())
}
// NTPSuboptionSrvFQDN is NTP_SUBOPTION_SRV_FQDN according to RFC 5908.
type NTPSuboptionSrvFQDN rfc1035label.Labels
// Code returns the suboption code.
func (n *NTPSuboptionSrvFQDN) Code() OptionCode {
return NTPSuboptionSrvFQDNCode
}
// ToBytes returns the byte serialization of the suboption.
func (n *NTPSuboptionSrvFQDN) ToBytes() []byte {
buf := uio.NewBigEndianBuffer(nil)
buf.Write16(uint16(NTPSuboptionSrvFQDNCode))
l := rfc1035label.Labels(*n)
buf.Write16(uint16(l.Length()))
buf.WriteBytes(l.ToBytes())
return buf.Data()
}
func (n *NTPSuboptionSrvFQDN) String() string {
l := rfc1035label.Labels(*n)
return fmt.Sprintf("Server FQDN: %s", l.String())
}
// NTPSuboptionSrvAddr is the value of NTP_SUBOPTION_SRV_ADDR according to RFC 5908.
const (
NTPSuboptionSrvAddrCode = OptionCode(1)
NTPSuboptionMCAddrCode = OptionCode(2)
NTPSuboptionSrvFQDNCode = OptionCode(3)
)
// parseNTPSuboption implements the OptionParser interface.
func parseNTPSuboption(code OptionCode, data []byte) (Option, error) {
//var o Options
buf := uio.NewBigEndianBuffer(data)
length := len(data)
data, err := buf.ReadN(length)
if err != nil {
return nil, fmt.Errorf("failed to read %d bytes for suboption: %w", length, err)
}
switch code {
case NTPSuboptionSrvAddrCode, NTPSuboptionMCAddrCode:
if length != net.IPv6len {
return nil, fmt.Errorf("invalid suboption length, want %d, got %d", net.IPv6len, length)
}
var so Option
switch code {
case NTPSuboptionSrvAddrCode:
sos := NTPSuboptionSrvAddr(data)
so = &sos
case NTPSuboptionMCAddrCode:
som := NTPSuboptionMCAddr(data)
so = &som
}
return so, nil
case NTPSuboptionSrvFQDNCode:
l, err := rfc1035label.FromBytes(data)
if err != nil {
return nil, fmt.Errorf("failed to parse rfc1035 labels: %w", err)
}
// TODO according to rfc3315, this label must not be compressed.
// Need to add support for compression detection to the
// `rfc1035label` package in order to do that.
so := NTPSuboptionSrvFQDN(*l)
return &so, nil
default:
gopt := OptionGeneric{OptionCode: code, OptionData: data}
return &gopt, nil
}
}
// ParseOptNTPServer parses a sequence of bytes into an OptNTPServer object.
func ParseOptNTPServer(data []byte) (*OptNTPServer, error) {
var so Options
if err := so.FromBytesWithParser(data, parseNTPSuboption); err != nil {
return nil, err
}
return &OptNTPServer{
Suboptions: so,
}, nil
}
// OptNTPServer is an option NTP server as defined by RFC 5908.
type OptNTPServer struct {
Suboptions Options
}
// Code returns the option code
func (op *OptNTPServer) Code() OptionCode {
return OptionNTPServer
}
// ToBytes returns the option serialized to bytes.
func (op *OptNTPServer) ToBytes() []byte {
buf := uio.NewBigEndianBuffer(nil)
for _, so := range op.Suboptions {
buf.WriteBytes(so.ToBytes())
}
return buf.Data()
}
func (op *OptNTPServer) String() string {
return fmt.Sprintf("NTP: %v", op.Suboptions)
}
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