Struct std::net::Ipv6Addr

pub struct Ipv6Addr { /* private fields */ }

An IPv6 address.

IPv6 addresses are defined as 128-bit integers in IETF RFC 4291. They are usually represented as eight 16-bit segments.

The size of an Ipv6Addr struct may vary depending on the target operating system.

Embedding IPv4 Addresses

See IpAddr for a type encompassing both IPv4 and IPv6 addresses.

To assist in the transition from IPv4 to IPv6 two types of IPv6 addresses that embed an IPv4 address were defined: IPv4-compatible and IPv4-mapped addresses. Of these IPv4-compatible addresses have been officially deprecated.

Both types of addresses are not assigned any special meaning by this implementation, other than what the relevant standards prescribe. This means that an address like ::ffff:127.0.0.1, while representing an IPv4 loopback address, is not itself an IPv6 loopback address; only ::1 is. To handle these so called “IPv4-in-IPv6” addresses, they have to first be converted to their canonical IPv4 address.

IPv4-Compatible IPv6 Addresses

IPv4-compatible IPv6 addresses are defined in IETF RFC 4291 Section 2.5.5.1, and have been officially deprecated. The RFC describes the format of an “IPv4-Compatible IPv6 address” as follows:

|                80 bits               | 16 |      32 bits        |
+--------------------------------------+--------------------------+
|0000..............................0000|0000|    IPv4 address     |
+--------------------------------------+----+---------------------+

So ::a.b.c.d would be an IPv4-compatible IPv6 address representing the IPv4 address a.b.c.d.

To convert from an IPv4 address to an IPv4-compatible IPv6 address, use Ipv4Addr::to_ipv6_compatible. Use Ipv6Addr::to_ipv4 to convert an IPv4-compatible IPv6 address to the canonical IPv4 address.

IPv4-Mapped IPv6 Addresses

IPv4-mapped IPv6 addresses are defined in IETF RFC 4291 Section 2.5.5.2. The RFC describes the format of an “IPv4-Mapped IPv6 address” as follows:

|                80 bits               | 16 |      32 bits        |
+--------------------------------------+--------------------------+
|0000..............................0000|FFFF|    IPv4 address     |
+--------------------------------------+----+---------------------+

So ::ffff:a.b.c.d would be an IPv4-mapped IPv6 address representing the IPv4 address a.b.c.d.

To convert from an IPv4 address to an IPv4-mapped IPv6 address, use Ipv4Addr::to_ipv6_mapped. Use Ipv6Addr::to_ipv4 to convert an IPv4-mapped IPv6 address to the canonical IPv4 address. Note that this will also convert the IPv6 loopback address ::1 to 0.0.0.1. Use Ipv6Addr::to_ipv4_mapped to avoid this.

Textual representation

Ipv6Addr provides a FromStr implementation. There are many ways to represent an IPv6 address in text, but in general, each segments is written in hexadecimal notation, and segments are separated by :. For more information, see IETF RFC 5952.

Examples

use std::net::Ipv6Addr;

let localhost = Ipv6Addr::new(0, 0, 0, 0, 0, 0, 0, 1);
assert_eq!("::1".parse(), Ok(localhost));
assert_eq!(localhost.is_loopback(), true);

Implementations

impl Ipv6Addr

pub const fn new(
    a: u16,
    b: u16,
    c: u16,
    d: u16,
    e: u16,
    f: u16,
    g: u16,
    h: u16
) -> Ipv6Addr

Creates a new IPv6 address from eight 16-bit segments.

The result will represent the IP address a:b:c:d:e:f:g:h.

Examples

use std::net::Ipv6Addr;

let addr = Ipv6Addr::new(0, 0, 0, 0, 0, 0xffff, 0xc00a, 0x2ff);

pub const LOCALHOST: Self = Ipv6Addr::new(0, 0, 0, 0, 0, 0, 0, 1)

An IPv6 address representing localhost: ::1.

Examples

use std::net::Ipv6Addr;

let addr = Ipv6Addr::LOCALHOST;
assert_eq!(addr, Ipv6Addr::new(0, 0, 0, 0, 0, 0, 0, 1));

pub const UNSPECIFIED: Self = Ipv6Addr::new(0, 0, 0, 0, 0, 0, 0, 0)

An IPv6 address representing the unspecified address: ::

Examples

use std::net::Ipv6Addr;

let addr = Ipv6Addr::UNSPECIFIED;
assert_eq!(addr, Ipv6Addr::new(0, 0, 0, 0, 0, 0, 0, 0));

pub const fn segments(&self) -> [u16; 8]

Returns the eight 16-bit segments that make up this address.

Examples

use std::net::Ipv6Addr;

assert_eq!(Ipv6Addr::new(0, 0, 0, 0, 0, 0xffff, 0xc00a, 0x2ff).segments(),
           [0, 0, 0, 0, 0, 0xffff, 0xc00a, 0x2ff]);

pub const fn is_unspecified(&self) -> bool

Returns true for the special ‘unspecified’ address (::).

This property is defined in IETF RFC 4291.

Examples

use std::net::Ipv6Addr;

assert_eq!(Ipv6Addr::new(0, 0, 0, 0, 0, 0xffff, 0xc00a, 0x2ff).is_unspecified(), false);
assert_eq!(Ipv6Addr::new(0, 0, 0, 0, 0, 0, 0, 0).is_unspecified(), true);

pub const fn is_loopback(&self) -> bool

Returns true if this is the loopback address (::1), as defined in IETF RFC 4291 section 2.5.3.

Contrary to IPv4, in IPv6 there is only one loopback address.

Examples

use std::net::Ipv6Addr;

assert_eq!(Ipv6Addr::new(0, 0, 0, 0, 0, 0xffff, 0xc00a, 0x2ff).is_loopback(), false);
assert_eq!(Ipv6Addr::new(0, 0, 0, 0, 0, 0, 0, 0x1).is_loopback(), true);

pub fn is_global(&self) -> bool

🔬 This is a nightly-only experimental API. (ip #27709)

Returns true if the address appears to be globally routable.

The following return false:

• the loopback address
• link-local and unique local unicast addresses
• interface-, link-, realm-, admin- and site-local multicast addresses

Examples

#![feature(ip)]

use std::net::Ipv6Addr;

assert_eq!(Ipv6Addr::new(0, 0, 0, 0, 0, 0xffff, 0xc00a, 0x2ff).is_global(), true);
assert_eq!(Ipv6Addr::new(0, 0, 0, 0, 0, 0, 0, 0x1).is_global(), false);
assert_eq!(Ipv6Addr::new(0, 0, 0x1c9, 0, 0, 0xafc8, 0, 0x1).is_global(), true);

pub fn is_unique_local(&self) -> bool

🔬 This is a nightly-only experimental API. (ip #27709)

Returns true if this is a unique local address (fc00::/7).

This property is defined in IETF RFC 4193.

Examples

#![feature(ip)]

use std::net::Ipv6Addr;

assert_eq!(Ipv6Addr::new(0, 0, 0, 0, 0, 0xffff, 0xc00a, 0x2ff).is_unique_local(), false);
assert_eq!(Ipv6Addr::new(0xfc02, 0, 0, 0, 0, 0, 0, 0).is_unique_local(), true);

pub fn is_unicast(&self) -> bool

🔬 This is a nightly-only experimental API. (ip #27709)

Returns true if this is a unicast address, as defined by IETF RFC 4291. Any address that is not a multicast address (ff00::/8) is unicast.

Examples

#![feature(ip)]

use std::net::Ipv6Addr;

// The unspecified and loopback addresses are unicast.
assert_eq!(Ipv6Addr::UNSPECIFIED.is_unicast(), true);
assert_eq!(Ipv6Addr::LOCALHOST.is_unicast(), true);

// Any address that is not a multicast address (`ff00::/8`) is unicast.
assert_eq!(Ipv6Addr::new(0x2001, 0xdb8, 0, 0, 0, 0, 0, 0).is_unicast(), true);
assert_eq!(Ipv6Addr::new(0xff00, 0, 0, 0, 0, 0, 0, 0).is_unicast(), false);

pub fn is_unicast_link_local(&self) -> bool

🔬 This is a nightly-only experimental API. (ip #27709)

Returns true if the address is a unicast address with link-local scope, as defined in RFC 4291.

A unicast address has link-local scope if it has the prefix fe80::/10, as per RFC 4291 section 2.4. Note that this encompasses more addresses than those defined in RFC 4291 section 2.5.6, which describes “Link-Local IPv6 Unicast Addresses” as having the following stricter format:

| 10 bits  |         54 bits         |          64 bits           |
+----------+-------------------------+----------------------------+
|1111111010|           0             |       interface ID         |
+----------+-------------------------+----------------------------+

So while currently the only addresses with link-local scope an application will encounter are all in fe80::/64, this might change in the future with the publication of new standards. More addresses in fe80::/10 could be allocated, and those addresses will have link-local scope.

Also note that while RFC 4291 section 2.5.3 mentions about the loopback address (::1) that “it is treated as having Link-Local scope”, this does not mean that the loopback address actually has link-local scope and this method will return false on it.

Examples

#![feature(ip)]

use std::net::Ipv6Addr;

// The loopback address (`::1`) does not actually have link-local scope.
assert_eq!(Ipv6Addr::LOCALHOST.is_unicast_link_local(), false);

// Only addresses in `fe80::/10` have link-local scope.
assert_eq!(Ipv6Addr::new(0x2001, 0xdb8, 0, 0, 0, 0, 0, 0).is_unicast_link_local(), false);
assert_eq!(Ipv6Addr::new(0xfe80, 0, 0, 0, 0, 0, 0, 0).is_unicast_link_local(), true);

// Addresses outside the stricter `fe80::/64` also have link-local scope.
assert_eq!(Ipv6Addr::new(0xfe80, 0, 0, 1, 0, 0, 0, 0).is_unicast_link_local(), true);
assert_eq!(Ipv6Addr::new(0xfe81, 0, 0, 0, 0, 0, 0, 0).is_unicast_link_local(), true);

pub fn is_documentation(&self) -> bool

🔬 This is a nightly-only experimental API. (ip #27709)

Returns true if this is an address reserved for documentation (2001:db8::/32).

This property is defined in IETF RFC 3849.

Examples

#![feature(ip)]

use std::net::Ipv6Addr;

assert_eq!(Ipv6Addr::new(0, 0, 0, 0, 0, 0xffff, 0xc00a, 0x2ff).is_documentation(), false);
assert_eq!(Ipv6Addr::new(0x2001, 0xdb8, 0, 0, 0, 0, 0, 0).is_documentation(), true);

pub const fn is_benchmarking(&self) -> bool

🔬 This is a nightly-only experimental API. (ip #27709)

Returns true if this is an address reserved for benchmarking (2001:2::/48).

This property is defined in IETF RFC 5180, where it is mistakenly specified as covering the range 2001:0200::/48. This is corrected in IETF RFC Errata 1752 to 2001:0002::/48.

#![feature(ip)]

use std::net::Ipv6Addr;

assert_eq!(Ipv6Addr::new(0, 0, 0, 0, 0, 0xffff, 0xc613, 0x0).is_benchmarking(), false);
assert_eq!(Ipv6Addr::new(0x2001, 0x2, 0, 0, 0, 0, 0, 0).is_benchmarking(), true);

pub fn is_unicast_global(&self) -> bool

🔬 This is a nightly-only experimental API. (ip #27709)

Returns true if the address is a globally routable unicast address.

The following return false:

• the loopback address
• the link-local addresses
• unique local addresses
• the unspecified address
• the address range reserved for documentation

This method returns true for site-local addresses as per RFC 4291 section 2.5.7

The special behavior of [the site-local unicast] prefix defined in [RFC3513] must no longer
be supported in new implementations (i.e., new implementations must treat this prefix as
Global Unicast).

Examples

#![feature(ip)]

use std::net::Ipv6Addr;

assert_eq!(Ipv6Addr::new(0x2001, 0xdb8, 0, 0, 0, 0, 0, 0).is_unicast_global(), false);
assert_eq!(Ipv6Addr::new(0, 0, 0, 0, 0, 0xffff, 0xc00a, 0x2ff).is_unicast_global(), true);

pub fn multicast_scope(&self) -> Option<Ipv6MulticastScope>

🔬 This is a nightly-only experimental API. (ip #27709)

Returns the address’s multicast scope if the address is multicast.

Examples

#![feature(ip)]

use std::net::{Ipv6Addr, Ipv6MulticastScope};

assert_eq!(
    Ipv6Addr::new(0xff0e, 0, 0, 0, 0, 0, 0, 0).multicast_scope(),
    Some(Ipv6MulticastScope::Global)
);
assert_eq!(Ipv6Addr::new(0, 0, 0, 0, 0, 0xffff, 0xc00a, 0x2ff).multicast_scope(), None);

pub const fn is_multicast(&self) -> bool

Returns true if this is a multicast address (ff00::/8).

This property is defined by IETF RFC 4291.

Examples

use std::net::Ipv6Addr;

assert_eq!(Ipv6Addr::new(0xff00, 0, 0, 0, 0, 0, 0, 0).is_multicast(), true);
assert_eq!(Ipv6Addr::new(0, 0, 0, 0, 0, 0xffff, 0xc00a, 0x2ff).is_multicast(), false);

pub fn to_ipv4_mapped(&self) -> Option<Ipv4Addr>

Converts this address to an IPv4 address if it’s an IPv4-mapped address, as defined in IETF RFC 4291 section 2.5.5.2, otherwise returns None.

::ffff:a.b.c.d becomes a.b.c.d. All addresses not starting with ::ffff will return None.

Examples

use std::net::{Ipv4Addr, Ipv6Addr};

assert_eq!(Ipv6Addr::new(0xff00, 0, 0, 0, 0, 0, 0, 0).to_ipv4_mapped(), None);
assert_eq!(Ipv6Addr::new(0, 0, 0, 0, 0, 0xffff, 0xc00a, 0x2ff).to_ipv4_mapped(),
           Some(Ipv4Addr::new(192, 10, 2, 255)));
assert_eq!(Ipv6Addr::new(0, 0, 0, 0, 0, 0, 0, 1).to_ipv4_mapped(), None);

pub const fn to_ipv4(&self) -> Option<Ipv4Addr>

Converts this address to an IPv4 address if it is either an IPv4-compatible address as defined in IETF RFC 4291 section 2.5.5.1, or an IPv4-mapped address as defined in IETF RFC 4291 section 2.5.5.2, otherwise returns None.

Note that this will return an IPv4 address for the IPv6 loopback address ::1. Use Ipv6Addr::to_ipv4_mapped to avoid this.

::a.b.c.d and ::ffff:a.b.c.d become a.b.c.d. ::1 becomes 0.0.0.1. All addresses not starting with either all zeroes or ::ffff will return None.

Examples

use std::net::{Ipv4Addr, Ipv6Addr};

assert_eq!(Ipv6Addr::new(0xff00, 0, 0, 0, 0, 0, 0, 0).to_ipv4(), None);
assert_eq!(Ipv6Addr::new(0, 0, 0, 0, 0, 0xffff, 0xc00a, 0x2ff).to_ipv4(),
           Some(Ipv4Addr::new(192, 10, 2, 255)));
assert_eq!(Ipv6Addr::new(0, 0, 0, 0, 0, 0, 0, 1).to_ipv4(),
           Some(Ipv4Addr::new(0, 0, 0, 1)));

pub fn to_canonical(&self) -> IpAddr

🔬 This is a nightly-only experimental API. (ip #27709)

Converts this address to an IpAddr::V4 if it is an IPv4-mapped addresses, otherwise it returns self wrapped in an IpAddr::V6.

Examples

#![feature(ip)]
use std::net::Ipv6Addr;

assert_eq!(Ipv6Addr::new(0, 0, 0, 0, 0, 0xffff, 0x7f00, 0x1).is_loopback(), false);
assert_eq!(Ipv6Addr::new(0, 0, 0, 0, 0, 0xffff, 0x7f00, 0x1).to_canonical().is_loopback(), true);

pub const fn octets(&self) -> [u8; 16]

Returns the sixteen eight-bit integers the IPv6 address consists of.

use std::net::Ipv6Addr;

assert_eq!(Ipv6Addr::new(0xff00, 0, 0, 0, 0, 0, 0, 0).octets(),
           [255, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0]);

Trait Implementations

impl Clone for Ipv6Addr

fn clone(&self) -> Ipv6Addr

Returns a copy of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl Debug for Ipv6Addr

fn fmt(&self, fmt: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl Display for Ipv6Addr

Write an Ipv6Addr, conforming to the canonical style described by RFC 5952.

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl From<[u16; 8]> for Ipv6Addr

fn from(segments: [u16; 8]) -> Ipv6Addr

Creates an Ipv6Addr from an eight element 16-bit array.

Examples

use std::net::Ipv6Addr;

let addr = Ipv6Addr::from([
    525u16, 524u16, 523u16, 522u16,
    521u16, 520u16, 519u16, 518u16,
]);
assert_eq!(
    Ipv6Addr::new(
        0x20d, 0x20c,
        0x20b, 0x20a,
        0x209, 0x208,
        0x207, 0x206
    ),
    addr
);

impl From<[u8; 16]> for Ipv6Addr

fn from(octets: [u8; 16]) -> Ipv6Addr

Creates an Ipv6Addr from a sixteen element byte array.

Examples

use std::net::Ipv6Addr;

let addr = Ipv6Addr::from([
    25u8, 24u8, 23u8, 22u8, 21u8, 20u8, 19u8, 18u8,
    17u8, 16u8, 15u8, 14u8, 13u8, 12u8, 11u8, 10u8,
]);
assert_eq!(
    Ipv6Addr::new(
        0x1918, 0x1716,
        0x1514, 0x1312,
        0x1110, 0x0f0e,
        0x0d0c, 0x0b0a
    ),
    addr
);

impl From<Ipv6Addr> for IpAddr

fn from(ipv6: Ipv6Addr) -> IpAddr

Copies this address to a new IpAddr::V6.

Examples

use std::net::{IpAddr, Ipv6Addr};

let addr = Ipv6Addr::new(0, 0, 0, 0, 0, 0xffff, 0xc00a, 0x2ff);

assert_eq!(
    IpAddr::V6(addr),
    IpAddr::from(addr)
);

impl From<Ipv6Addr> for u128

fn from(ip: Ipv6Addr) -> u128

Convert an Ipv6Addr into a host byte order u128.

Examples

use std::net::Ipv6Addr;

let addr = Ipv6Addr::new(
    0x1020, 0x3040, 0x5060, 0x7080,
    0x90A0, 0xB0C0, 0xD0E0, 0xF00D,
);
assert_eq!(0x102030405060708090A0B0C0D0E0F00D_u128, u128::from(addr));

impl From<u128> for Ipv6Addr

fn from(ip: u128) -> Ipv6Addr

Convert a host byte order u128 into an Ipv6Addr.

Examples

use std::net::Ipv6Addr;

let addr = Ipv6Addr::from(0x102030405060708090A0B0C0D0E0F00D_u128);
assert_eq!(
    Ipv6Addr::new(
        0x1020, 0x3040, 0x5060, 0x7080,
        0x90A0, 0xB0C0, 0xD0E0, 0xF00D,
    ),
    addr);

impl FromStr for Ipv6Addr

type Err = AddrParseError

The associated error which can be returned from parsing.

fn from_str(s: &str) -> Result<Ipv6Addr, AddrParseError>

Parses a string s to return a value of this type.

impl Hash for Ipv6Addr

fn hash<H: Hasher>(&self, s: &mut H)

Feeds this value into the given Hasher.

fn hash_slice<H>(data: &[Self], state: &mut H) where
    H: Hasher, 

Feeds a slice of this type into the given Hasher.

impl Ord for Ipv6Addr

fn cmp(&self, other: &Ipv6Addr) -> Ordering

This method returns an Ordering between self and other.

fn max(self, other: Self) -> Self

Compares and returns the maximum of two values.

fn min(self, other: Self) -> Self

Compares and returns the minimum of two values.

fn clamp(self, min: Self, max: Self) -> Self

Restrict a value to a certain interval.

impl PartialEq<IpAddr> for Ipv6Addr

fn eq(&self, other: &IpAddr) -> bool

This method tests for self and other values to be equal, and is used by ==.

fn ne(&self, other: &Rhs) -> bool

This method tests for !=.

impl PartialEq<Ipv6Addr> for Ipv6Addr

fn eq(&self, other: &Ipv6Addr) -> bool

This method tests for self and other values to be equal, and is used by ==.

fn ne(&self, other: &Rhs) -> bool

This method tests for !=.

impl PartialEq<Ipv6Addr> for IpAddr

fn eq(&self, other: &Ipv6Addr) -> bool

This method tests for self and other values to be equal, and is used by ==.

fn ne(&self, other: &Rhs) -> bool

This method tests for !=.

impl PartialOrd<IpAddr> for Ipv6Addr

fn partial_cmp(&self, other: &IpAddr) -> Option<Ordering>

This method returns an ordering between self and other values if one exists.

fn lt(&self, other: &Rhs) -> bool

This method tests less than (for self and other) and is used by the < operator.

fn le(&self, other: &Rhs) -> bool

This method tests less than or equal to (for self and other) and is used by the <= operator.

fn gt(&self, other: &Rhs) -> bool

This method tests greater than (for self and other) and is used by the > operator.

fn ge(&self, other: &Rhs) -> bool

This method tests greater than or equal to (for self and other) and is used by the >= operator.

impl PartialOrd<Ipv6Addr> for Ipv6Addr

fn partial_cmp(&self, other: &Ipv6Addr) -> Option<Ordering>

This method returns an ordering between self and other values if one exists.

fn lt(&self, other: &Rhs) -> bool

This method tests less than (for self and other) and is used by the < operator.

fn le(&self, other: &Rhs) -> bool

This method tests less than or equal to (for self and other) and is used by the <= operator.

fn gt(&self, other: &Rhs) -> bool

This method tests greater than (for self and other) and is used by the > operator.

fn ge(&self, other: &Rhs) -> bool

This method tests greater than or equal to (for self and other) and is used by the >= operator.

impl PartialOrd<Ipv6Addr> for IpAddr

fn partial_cmp(&self, other: &Ipv6Addr) -> Option<Ordering>

This method returns an ordering between self and other values if one exists.

fn lt(&self, other: &Rhs) -> bool

This method tests less than (for self and other) and is used by the < operator.

fn le(&self, other: &Rhs) -> bool

This method tests less than or equal to (for self and other) and is used by the <= operator.

fn gt(&self, other: &Rhs) -> bool

This method tests greater than (for self and other) and is used by the > operator.

fn ge(&self, other: &Rhs) -> bool

This method tests greater than or equal to (for self and other) and is used by the >= operator.

impl Copy for Ipv6Addr

impl Eq for Ipv6Addr