mirror of
https://github.com/superseriousbusiness/gotosocial.git
synced 2024-12-04 22:20:53 +01:00
56 lines
1.5 KiB
Go
56 lines
1.5 KiB
Go
// Copyright 2014 The Go Authors. All rights reserved.
|
|
// Use of this source code is governed by a BSD-style
|
|
// license that can be found in the LICENSE file.
|
|
|
|
package ipv6
|
|
|
|
import (
|
|
"encoding/binary"
|
|
"fmt"
|
|
"net"
|
|
)
|
|
|
|
const (
|
|
Version = 6 // protocol version
|
|
HeaderLen = 40 // header length
|
|
)
|
|
|
|
// A Header represents an IPv6 base header.
|
|
type Header struct {
|
|
Version int // protocol version
|
|
TrafficClass int // traffic class
|
|
FlowLabel int // flow label
|
|
PayloadLen int // payload length
|
|
NextHeader int // next header
|
|
HopLimit int // hop limit
|
|
Src net.IP // source address
|
|
Dst net.IP // destination address
|
|
}
|
|
|
|
func (h *Header) String() string {
|
|
if h == nil {
|
|
return "<nil>"
|
|
}
|
|
return fmt.Sprintf("ver=%d tclass=%#x flowlbl=%#x payloadlen=%d nxthdr=%d hoplim=%d src=%v dst=%v", h.Version, h.TrafficClass, h.FlowLabel, h.PayloadLen, h.NextHeader, h.HopLimit, h.Src, h.Dst)
|
|
}
|
|
|
|
// ParseHeader parses b as an IPv6 base header.
|
|
func ParseHeader(b []byte) (*Header, error) {
|
|
if len(b) < HeaderLen {
|
|
return nil, errHeaderTooShort
|
|
}
|
|
h := &Header{
|
|
Version: int(b[0]) >> 4,
|
|
TrafficClass: int(b[0]&0x0f)<<4 | int(b[1])>>4,
|
|
FlowLabel: int(b[1]&0x0f)<<16 | int(b[2])<<8 | int(b[3]),
|
|
PayloadLen: int(binary.BigEndian.Uint16(b[4:6])),
|
|
NextHeader: int(b[6]),
|
|
HopLimit: int(b[7]),
|
|
}
|
|
h.Src = make(net.IP, net.IPv6len)
|
|
copy(h.Src, b[8:24])
|
|
h.Dst = make(net.IP, net.IPv6len)
|
|
copy(h.Dst, b[24:40])
|
|
return h, nil
|
|
}
|