1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
|
package dhcpv4
import (
"fmt"
"net"
)
// This option implements the server identifier option
// https://tools.ietf.org/html/rfc2132
// OptBroadcastAddress represents an option encapsulating the server identifier.
type OptBroadcastAddress struct {
BroadcastAddress net.IP
}
// ParseOptBroadcastAddress returns a new OptBroadcastAddress from a byte
// stream, or error if any.
func ParseOptBroadcastAddress(data []byte) (*OptBroadcastAddress, error) {
if len(data) < 2 {
return nil, ErrShortByteStream
}
code := OptionCode(data[0])
if code != OptionBroadcastAddress {
return nil, fmt.Errorf("expected code %v, got %v", OptionBroadcastAddress, code)
}
length := int(data[1])
if length != 4 {
return nil, fmt.Errorf("unexepcted length: expected 4, got %v", length)
}
if len(data) < 6 {
return nil, ErrShortByteStream
}
return &OptBroadcastAddress{BroadcastAddress: net.IP(data[2 : 2+length])}, nil
}
// Code returns the option code.
func (o *OptBroadcastAddress) Code() OptionCode {
return OptionBroadcastAddress
}
// ToBytes returns a serialized stream of bytes for this option.
func (o *OptBroadcastAddress) ToBytes() []byte {
ret := []byte{byte(o.Code()), byte(o.Length())}
return append(ret, o.BroadcastAddress.To4()...)
}
// String returns a human-readable string.
func (o *OptBroadcastAddress) String() string {
return fmt.Sprintf("Broadcast Address -> %v", o.BroadcastAddress.String())
}
// Length returns the length of the data portion (excluding option code an byte
// length).
func (o *OptBroadcastAddress) Length() int {
return len(o.BroadcastAddress.To4())
}
|