open-consul/vendor/github.com/hashicorp/go-sockaddr/ipv6addr.go

592 lines
16 KiB
Go

package sockaddr
import (
"bytes"
"encoding/binary"
"fmt"
"math/big"
"net"
)
type (
// IPv6Address is a named type representing an IPv6 address.
IPv6Address *big.Int
// IPv6Network is a named type representing an IPv6 network.
IPv6Network *big.Int
// IPv6Mask is a named type representing an IPv6 network mask.
IPv6Mask *big.Int
)
// IPv6HostPrefix is a constant represents a /128 IPv6 Prefix.
const IPv6HostPrefix = IPPrefixLen(128)
// ipv6HostMask is an unexported big.Int representing a /128 IPv6 address.
// This value must be a constant and always set to all ones.
var ipv6HostMask IPv6Mask
// ipv6AddrAttrMap is a map of the IPv6Addr type-specific attributes.
var ipv6AddrAttrMap map[AttrName]func(IPv6Addr) string
var ipv6AddrAttrs []AttrName
func init() {
biMask := new(big.Int)
biMask.SetBytes([]byte{
0xff, 0xff,
0xff, 0xff,
0xff, 0xff,
0xff, 0xff,
0xff, 0xff,
0xff, 0xff,
0xff, 0xff,
0xff, 0xff,
},
)
ipv6HostMask = IPv6Mask(biMask)
ipv6AddrInit()
}
// IPv6Addr implements a convenience wrapper around the union of Go's
// built-in net.IP and net.IPNet types. In UNIX-speak, IPv6Addr implements
// `sockaddr` when the the address family is set to AF_INET6
// (i.e. `sockaddr_in6`).
type IPv6Addr struct {
IPAddr
Address IPv6Address
Mask IPv6Mask
Port IPPort
}
// NewIPv6Addr creates an IPv6Addr from a string. String can be in the form of
// an an IPv6:port (e.g. `[2001:4860:0:2001::68]:80`, in which case the mask is
// assumed to be a /128), an IPv6 address (e.g. `2001:4860:0:2001::68`, also
// with a `/128` mask), an IPv6 CIDR (e.g. `2001:4860:0:2001::68/64`, which has
// its IP port initialized to zero). ipv6Str can not be a hostname.
//
// NOTE: Many net.*() routines will initialize and return an IPv4 address.
// Always test to make sure the address returned cannot be converted to a 4 byte
// array using To4().
func NewIPv6Addr(ipv6Str string) (IPv6Addr, error) {
v6Addr := false
LOOP:
for i := 0; i < len(ipv6Str); i++ {
switch ipv6Str[i] {
case '.':
break LOOP
case ':':
v6Addr = true
break LOOP
}
}
if !v6Addr {
return IPv6Addr{}, fmt.Errorf("Unable to resolve %+q as an IPv6 address, appears to be an IPv4 address", ipv6Str)
}
// Attempt to parse ipv6Str as a /128 host with a port number.
tcpAddr, err := net.ResolveTCPAddr("tcp6", ipv6Str)
if err == nil {
ipv6 := tcpAddr.IP.To16()
if ipv6 == nil {
return IPv6Addr{}, fmt.Errorf("Unable to resolve %+q as a 16byte IPv6 address", ipv6Str)
}
ipv6BigIntAddr := new(big.Int)
ipv6BigIntAddr.SetBytes(ipv6)
ipv6BigIntMask := new(big.Int)
ipv6BigIntMask.Set(ipv6HostMask)
ipv6Addr := IPv6Addr{
Address: IPv6Address(ipv6BigIntAddr),
Mask: IPv6Mask(ipv6BigIntMask),
Port: IPPort(tcpAddr.Port),
}
return ipv6Addr, nil
}
// Parse as a naked IPv6 address. Trim square brackets if present.
if len(ipv6Str) > 2 && ipv6Str[0] == '[' && ipv6Str[len(ipv6Str)-1] == ']' {
ipv6Str = ipv6Str[1 : len(ipv6Str)-1]
}
ip := net.ParseIP(ipv6Str)
if ip != nil {
ipv6 := ip.To16()
if ipv6 == nil {
return IPv6Addr{}, fmt.Errorf("Unable to string convert %+q to a 16byte IPv6 address", ipv6Str)
}
ipv6BigIntAddr := new(big.Int)
ipv6BigIntAddr.SetBytes(ipv6)
ipv6BigIntMask := new(big.Int)
ipv6BigIntMask.Set(ipv6HostMask)
return IPv6Addr{
Address: IPv6Address(ipv6BigIntAddr),
Mask: IPv6Mask(ipv6BigIntMask),
}, nil
}
// Parse as an IPv6 CIDR
ipAddr, network, err := net.ParseCIDR(ipv6Str)
if err == nil {
ipv6 := ipAddr.To16()
if ipv6 == nil {
return IPv6Addr{}, fmt.Errorf("Unable to convert %+q to a 16byte IPv6 address", ipv6Str)
}
ipv6BigIntAddr := new(big.Int)
ipv6BigIntAddr.SetBytes(ipv6)
ipv6BigIntMask := new(big.Int)
ipv6BigIntMask.SetBytes(network.Mask)
ipv6Addr := IPv6Addr{
Address: IPv6Address(ipv6BigIntAddr),
Mask: IPv6Mask(ipv6BigIntMask),
}
return ipv6Addr, nil
}
return IPv6Addr{}, fmt.Errorf("Unable to parse %+q to an IPv6 address: %v", ipv6Str, err)
}
// AddressBinString returns a string with the IPv6Addr's Address represented
// as a sequence of '0' and '1' characters. This method is useful for
// debugging or by operators who want to inspect an address.
func (ipv6 IPv6Addr) AddressBinString() string {
bi := big.Int(*ipv6.Address)
return fmt.Sprintf("%0128s", bi.Text(2))
}
// AddressHexString returns a string with the IPv6Addr address represented as
// a sequence of hex characters. This method is useful for debugging or by
// operators who want to inspect an address.
func (ipv6 IPv6Addr) AddressHexString() string {
bi := big.Int(*ipv6.Address)
return fmt.Sprintf("%032s", bi.Text(16))
}
// CmpAddress follows the Cmp() standard protocol and returns:
//
// - -1 If the receiver should sort first because its address is lower than arg
// - 0 if the SockAddr arg equal to the receiving IPv6Addr or the argument is of a
// different type.
// - 1 If the argument should sort first.
func (ipv6 IPv6Addr) CmpAddress(sa SockAddr) int {
ipv6b, ok := sa.(IPv6Addr)
if !ok {
return sortDeferDecision
}
ipv6aBigInt := new(big.Int)
ipv6aBigInt.Set(ipv6.Address)
ipv6bBigInt := new(big.Int)
ipv6bBigInt.Set(ipv6b.Address)
return ipv6aBigInt.Cmp(ipv6bBigInt)
}
// CmpPort follows the Cmp() standard protocol and returns:
//
// - -1 If the receiver should sort first because its port is lower than arg
// - 0 if the SockAddr arg's port number is equal to the receiving IPv6Addr,
// regardless of type.
// - 1 If the argument should sort first.
func (ipv6 IPv6Addr) CmpPort(sa SockAddr) int {
var saPort IPPort
switch v := sa.(type) {
case IPv4Addr:
saPort = v.Port
case IPv6Addr:
saPort = v.Port
default:
return sortDeferDecision
}
switch {
case ipv6.Port == saPort:
return sortDeferDecision
case ipv6.Port < saPort:
return sortReceiverBeforeArg
default:
return sortArgBeforeReceiver
}
}
// CmpRFC follows the Cmp() standard protocol and returns:
//
// - -1 If the receiver should sort first because it belongs to the RFC and its
// arg does not
// - 0 if the receiver and arg both belong to the same RFC or neither do.
// - 1 If the arg belongs to the RFC but receiver does not.
func (ipv6 IPv6Addr) CmpRFC(rfcNum uint, sa SockAddr) int {
recvInRFC := IsRFC(rfcNum, ipv6)
ipv6b, ok := sa.(IPv6Addr)
if !ok {
// If the receiver is part of the desired RFC and the SockAddr
// argument is not, sort receiver before the non-IPv6 SockAddr.
// Conversely, if the receiver is not part of the RFC, punt on
// sorting and leave it for the next sorter.
if recvInRFC {
return sortReceiverBeforeArg
} else {
return sortDeferDecision
}
}
argInRFC := IsRFC(rfcNum, ipv6b)
switch {
case (recvInRFC && argInRFC), (!recvInRFC && !argInRFC):
// If a and b both belong to the RFC, or neither belong to
// rfcNum, defer sorting to the next sorter.
return sortDeferDecision
case recvInRFC && !argInRFC:
return sortReceiverBeforeArg
default:
return sortArgBeforeReceiver
}
}
// Contains returns true if the SockAddr is contained within the receiver.
func (ipv6 IPv6Addr) Contains(sa SockAddr) bool {
ipv6b, ok := sa.(IPv6Addr)
if !ok {
return false
}
return ipv6.ContainsNetwork(ipv6b)
}
// ContainsAddress returns true if the IPv6Address is contained within the
// receiver.
func (ipv6 IPv6Addr) ContainsAddress(x IPv6Address) bool {
xAddr := IPv6Addr{
Address: x,
Mask: ipv6HostMask,
}
{
xIPv6 := xAddr.FirstUsable().(IPv6Addr)
yIPv6 := ipv6.FirstUsable().(IPv6Addr)
if xIPv6.CmpAddress(yIPv6) >= 1 {
return false
}
}
{
xIPv6 := xAddr.LastUsable().(IPv6Addr)
yIPv6 := ipv6.LastUsable().(IPv6Addr)
if xIPv6.CmpAddress(yIPv6) <= -1 {
return false
}
}
return true
}
// ContainsNetwork returns true if the network from IPv6Addr is contained within
// the receiver.
func (x IPv6Addr) ContainsNetwork(y IPv6Addr) bool {
{
xIPv6 := x.FirstUsable().(IPv6Addr)
yIPv6 := y.FirstUsable().(IPv6Addr)
if ret := xIPv6.CmpAddress(yIPv6); ret >= 1 {
return false
}
}
{
xIPv6 := x.LastUsable().(IPv6Addr)
yIPv6 := y.LastUsable().(IPv6Addr)
if ret := xIPv6.CmpAddress(yIPv6); ret <= -1 {
return false
}
}
return true
}
// DialPacketArgs returns the arguments required to be passed to
// net.DialUDP(). If the Mask of ipv6 is not a /128 or the Port is 0,
// DialPacketArgs() will fail. See Host() to create an IPv6Addr with its
// mask set to /128.
func (ipv6 IPv6Addr) DialPacketArgs() (network, dialArgs string) {
ipv6Mask := big.Int(*ipv6.Mask)
if ipv6Mask.Cmp(ipv6HostMask) != 0 || ipv6.Port == 0 {
return "udp6", ""
}
return "udp6", fmt.Sprintf("[%s]:%d", ipv6.NetIP().String(), ipv6.Port)
}
// DialStreamArgs returns the arguments required to be passed to
// net.DialTCP(). If the Mask of ipv6 is not a /128 or the Port is 0,
// DialStreamArgs() will fail. See Host() to create an IPv6Addr with its
// mask set to /128.
func (ipv6 IPv6Addr) DialStreamArgs() (network, dialArgs string) {
ipv6Mask := big.Int(*ipv6.Mask)
if ipv6Mask.Cmp(ipv6HostMask) != 0 || ipv6.Port == 0 {
return "tcp6", ""
}
return "tcp6", fmt.Sprintf("[%s]:%d", ipv6.NetIP().String(), ipv6.Port)
}
// Equal returns true if a SockAddr is equal to the receiving IPv4Addr.
func (ipv6a IPv6Addr) Equal(sa SockAddr) bool {
ipv6b, ok := sa.(IPv6Addr)
if !ok {
return false
}
if ipv6a.NetIP().String() != ipv6b.NetIP().String() {
return false
}
if ipv6a.NetIPNet().String() != ipv6b.NetIPNet().String() {
return false
}
if ipv6a.Port != ipv6b.Port {
return false
}
return true
}
// FirstUsable returns an IPv6Addr set to the first address following the
// network prefix. The first usable address in a network is normally the
// gateway and should not be used except by devices forwarding packets
// between two administratively distinct networks (i.e. a router). This
// function does not discriminate against first usable vs "first address that
// should be used." For example, FirstUsable() on "2001:0db8::0003/64" would
// return "2001:0db8::00011".
func (ipv6 IPv6Addr) FirstUsable() IPAddr {
return IPv6Addr{
Address: IPv6Address(ipv6.NetworkAddress()),
Mask: ipv6HostMask,
}
}
// Host returns a copy of ipv6 with its mask set to /128 so that it can be
// used by DialPacketArgs(), DialStreamArgs(), ListenPacketArgs(), or
// ListenStreamArgs().
func (ipv6 IPv6Addr) Host() IPAddr {
// Nothing should listen on a broadcast address.
return IPv6Addr{
Address: ipv6.Address,
Mask: ipv6HostMask,
Port: ipv6.Port,
}
}
// IPPort returns the Port number attached to the IPv6Addr
func (ipv6 IPv6Addr) IPPort() IPPort {
return ipv6.Port
}
// LastUsable returns the last address in a given network.
func (ipv6 IPv6Addr) LastUsable() IPAddr {
addr := new(big.Int)
addr.Set(ipv6.Address)
mask := new(big.Int)
mask.Set(ipv6.Mask)
negMask := new(big.Int)
negMask.Xor(ipv6HostMask, mask)
lastAddr := new(big.Int)
lastAddr.And(addr, mask)
lastAddr.Or(lastAddr, negMask)
return IPv6Addr{
Address: IPv6Address(lastAddr),
Mask: ipv6HostMask,
}
}
// ListenPacketArgs returns the arguments required to be passed to
// net.ListenUDP(). If the Mask of ipv6 is not a /128, ListenPacketArgs()
// will fail. See Host() to create an IPv6Addr with its mask set to /128.
func (ipv6 IPv6Addr) ListenPacketArgs() (network, listenArgs string) {
ipv6Mask := big.Int(*ipv6.Mask)
if ipv6Mask.Cmp(ipv6HostMask) != 0 {
return "udp6", ""
}
return "udp6", fmt.Sprintf("[%s]:%d", ipv6.NetIP().String(), ipv6.Port)
}
// ListenStreamArgs returns the arguments required to be passed to
// net.ListenTCP(). If the Mask of ipv6 is not a /128, ListenStreamArgs()
// will fail. See Host() to create an IPv6Addr with its mask set to /128.
func (ipv6 IPv6Addr) ListenStreamArgs() (network, listenArgs string) {
ipv6Mask := big.Int(*ipv6.Mask)
if ipv6Mask.Cmp(ipv6HostMask) != 0 {
return "tcp6", ""
}
return "tcp6", fmt.Sprintf("[%s]:%d", ipv6.NetIP().String(), ipv6.Port)
}
// Maskbits returns the number of network mask bits in a given IPv6Addr. For
// example, the Maskbits() of "2001:0db8::0003/64" would return 64.
func (ipv6 IPv6Addr) Maskbits() int {
maskOnes, _ := ipv6.NetIPNet().Mask.Size()
return maskOnes
}
// MustIPv6Addr is a helper method that must return an IPv6Addr or panic on
// invalid input.
func MustIPv6Addr(addr string) IPv6Addr {
ipv6, err := NewIPv6Addr(addr)
if err != nil {
panic(fmt.Sprintf("Unable to create an IPv6Addr from %+q: %v", addr, err))
}
return ipv6
}
// NetIP returns the address as a net.IP.
func (ipv6 IPv6Addr) NetIP() *net.IP {
return bigIntToNetIPv6(ipv6.Address)
}
// NetIPMask create a new net.IPMask from the IPv6Addr.
func (ipv6 IPv6Addr) NetIPMask() *net.IPMask {
ipv6Mask := make(net.IPMask, IPv6len)
m := big.Int(*ipv6.Mask)
copy(ipv6Mask, m.Bytes())
return &ipv6Mask
}
// Network returns a pointer to the net.IPNet within IPv4Addr receiver.
func (ipv6 IPv6Addr) NetIPNet() *net.IPNet {
ipv6net := &net.IPNet{}
ipv6net.IP = make(net.IP, IPv6len)
copy(ipv6net.IP, *ipv6.NetIP())
ipv6net.Mask = *ipv6.NetIPMask()
return ipv6net
}
// Network returns the network prefix or network address for a given network.
func (ipv6 IPv6Addr) Network() IPAddr {
return IPv6Addr{
Address: IPv6Address(ipv6.NetworkAddress()),
Mask: ipv6.Mask,
}
}
// NetworkAddress returns an IPv6Network of the IPv6Addr's network address.
func (ipv6 IPv6Addr) NetworkAddress() IPv6Network {
addr := new(big.Int)
addr.SetBytes((*ipv6.Address).Bytes())
mask := new(big.Int)
mask.SetBytes(*ipv6.NetIPMask())
netAddr := new(big.Int)
netAddr.And(addr, mask)
return IPv6Network(netAddr)
}
// Octets returns a slice of the 16 octets in an IPv6Addr's Address. The
// order of the bytes is big endian.
func (ipv6 IPv6Addr) Octets() []int {
x := make([]int, IPv6len)
for i, b := range *bigIntToNetIPv6(ipv6.Address) {
x[i] = int(b)
}
return x
}
// String returns a string representation of the IPv6Addr
func (ipv6 IPv6Addr) String() string {
if ipv6.Port != 0 {
return fmt.Sprintf("[%s]:%d", ipv6.NetIP().String(), ipv6.Port)
}
if ipv6.Maskbits() == 128 {
return ipv6.NetIP().String()
}
return fmt.Sprintf("%s/%d", ipv6.NetIP().String(), ipv6.Maskbits())
}
// Type is used as a type switch and returns TypeIPv6
func (IPv6Addr) Type() SockAddrType {
return TypeIPv6
}
// IPv6Attrs returns a list of attributes supported by the IPv6Addr type
func IPv6Attrs() []AttrName {
return ipv6AddrAttrs
}
// IPv6AddrAttr returns a string representation of an attribute for the given
// IPv6Addr.
func IPv6AddrAttr(ipv6 IPv6Addr, selector AttrName) string {
fn, found := ipv6AddrAttrMap[selector]
if !found {
return ""
}
return fn(ipv6)
}
// ipv6AddrInit is called once at init()
func ipv6AddrInit() {
// Sorted for human readability
ipv6AddrAttrs = []AttrName{
"size", // Same position as in IPv6 for output consistency
"uint128",
}
ipv6AddrAttrMap = map[AttrName]func(ipv6 IPv6Addr) string{
"size": func(ipv6 IPv6Addr) string {
netSize := big.NewInt(1)
netSize = netSize.Lsh(netSize, uint(IPv6len*8-ipv6.Maskbits()))
return netSize.Text(10)
},
"uint128": func(ipv6 IPv6Addr) string {
b := big.Int(*ipv6.Address)
return b.Text(10)
},
}
}
// bigIntToNetIPv6 is a helper function that correctly returns a net.IP with the
// correctly padded values.
func bigIntToNetIPv6(bi *big.Int) *net.IP {
x := make(net.IP, IPv6len)
ipv6Bytes := bi.Bytes()
// It's possibe for ipv6Bytes to be less than IPv6len bytes in size. If
// they are different sizes we to pad the size of response.
if len(ipv6Bytes) < IPv6len {
buf := new(bytes.Buffer)
buf.Grow(IPv6len)
for i := len(ipv6Bytes); i < IPv6len; i++ {
if err := binary.Write(buf, binary.BigEndian, byte(0)); err != nil {
panic(fmt.Sprintf("Unable to pad byte %d of input %v: %v", i, bi, err))
}
}
for _, b := range ipv6Bytes {
if err := binary.Write(buf, binary.BigEndian, b); err != nil {
panic(fmt.Sprintf("Unable to preserve endianness of input %v: %v", bi, err))
}
}
ipv6Bytes = buf.Bytes()
}
i := copy(x, ipv6Bytes)
if i != IPv6len {
panic("IPv6 wrong size")
}
return &x
}