diff options
| -rw-r--r-- | dhcpv6/dhcpv6.go | 65 |
1 files changed, 45 insertions, 20 deletions
diff --git a/dhcpv6/dhcpv6.go b/dhcpv6/dhcpv6.go index 79ae299..41fbda8 100644 --- a/dhcpv6/dhcpv6.go +++ b/dhcpv6/dhcpv6.go @@ -28,32 +28,57 @@ type DHCPv6 interface { // structures. This is used to simplify packet manipulation type Modifier func(d DHCPv6) DHCPv6 -func FromBytes(data []byte) (DHCPv6, error) { +// MessageFromBytes parses a DHCPv6 message from a byte stream. +func MessageFromBytes(data []byte) (*Message, error) { buf := uio.NewBigEndianBuffer(data) messageType := MessageType(buf.Read8()) if messageType == MessageTypeRelayForward || messageType == MessageTypeRelayReply { - d := RelayMessage{ - messageType: messageType, - hopCount: buf.Read8(), - } - d.linkAddr = net.IP(buf.CopyN(net.IPv6len)) - d.peerAddr = net.IP(buf.CopyN(net.IPv6len)) + return nil, fmt.Errorf("wrong message type") + } - // TODO fail if no OptRelayMessage is present - if err := d.options.FromBytes(buf.Data()); err != nil { - return nil, err - } - return &d, nil + d := &Message{ + messageType: messageType, + } + buf.ReadBytes(d.transactionID[:]) + if err := d.options.FromBytes(buf.Data()); err != nil { + return nil, err + } + return d, nil +} + +// RelayMessageFromBytes parses a relay message from a byte stream. +func RelayMessageFromBytes(data []byte) (*RelayMessage, error) { + buf := uio.NewBigEndianBuffer(data) + messageType := MessageType(buf.Read8()) + + if messageType != MessageTypeRelayForward && messageType != MessageTypeRelayReply { + return nil, fmt.Errorf("wrong message type") + } + + d := &RelayMessage{ + messageType: messageType, + hopCount: buf.Read8(), + } + d.linkAddr = net.IP(buf.CopyN(net.IPv6len)) + d.peerAddr = net.IP(buf.CopyN(net.IPv6len)) + + // TODO: fail if no OptRelayMessage is present. + if err := d.options.FromBytes(buf.Data()); err != nil { + return nil, err + } + return d, nil +} + +// FromBytes reads a DHCPv6 message from a byte stream. +func FromBytes(data []byte) (DHCPv6, error) { + buf := uio.NewBigEndianBuffer(data) + messageType := MessageType(buf.Read8()) + + if messageType == MessageTypeRelayForward || messageType == MessageTypeRelayReply { + return RelayMessageFromBytes(data) } else { - d := Message{ - messageType: messageType, - } - buf.ReadBytes(d.transactionID[:]) - if err := d.options.FromBytes(buf.Data()); err != nil { - return nil, err - } - return &d, nil + return MessageFromBytes(data) } } |