Adding upstream version 1.64.0+dfsg1.upstream/1.64.0+dfsg1

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

12 files changed, 8025 insertions, 0 deletions

diff --git a/library/std/src/net/addr.rs b/library/std/src/net/addr.rs
new file mode 100644
index 000000000..53fee952a
--- /dev/null
+++ b/library/std/src/net/addr.rs
@@ -0,0 +1,988 @@
+#[cfg(all(test, not(target_os = "emscripten")))]
+mod tests;
+
+use crate::cmp::Ordering;
+use crate::fmt;
+use crate::hash;
+use crate::io::{self, Write};
+use crate::iter;
+use crate::mem;
+use crate::net::{IpAddr, Ipv4Addr, Ipv6Addr};
+use crate::option;
+use crate::slice;
+use crate::sys::net::netc as c;
+use crate::sys_common::net::LookupHost;
+use crate::sys_common::{FromInner, IntoInner};
+use crate::vec;
+
+/// An internet socket address, either IPv4 or IPv6.
+///
+/// Internet socket addresses consist of an [IP address], a 16-bit port number, as well
+/// as possibly some version-dependent additional information. See [`SocketAddrV4`]'s and
+/// [`SocketAddrV6`]'s respective documentation for more details.
+///
+/// The size of a `SocketAddr` instance may vary depending on the target operating
+/// system.
+///
+/// [IP address]: IpAddr
+///
+/// # Examples
+///
+/// ```
+/// use std::net::{IpAddr, Ipv4Addr, SocketAddr};
+///
+/// let socket = SocketAddr::new(IpAddr::V4(Ipv4Addr::new(127, 0, 0, 1)), 8080);
+///
+/// assert_eq!("127.0.0.1:8080".parse(), Ok(socket));
+/// assert_eq!(socket.port(), 8080);
+/// assert_eq!(socket.is_ipv4(), true);
+/// ```
+#[derive(Copy, Clone, PartialEq, Eq, Hash, PartialOrd, Ord)]
+#[stable(feature = "rust1", since = "1.0.0")]
+pub enum SocketAddr {
+    /// An IPv4 socket address.
+    #[stable(feature = "rust1", since = "1.0.0")]
+    V4(#[stable(feature = "rust1", since = "1.0.0")] SocketAddrV4),
+    /// An IPv6 socket address.
+    #[stable(feature = "rust1", since = "1.0.0")]
+    V6(#[stable(feature = "rust1", since = "1.0.0")] SocketAddrV6),
+}
+
+/// An IPv4 socket address.
+///
+/// IPv4 socket addresses consist of an [`IPv4` address] and a 16-bit port number, as
+/// stated in [IETF RFC 793].
+///
+/// See [`SocketAddr`] for a type encompassing both IPv4 and IPv6 socket addresses.
+///
+/// The size of a `SocketAddrV4` struct may vary depending on the target operating
+/// system. Do not assume that this type has the same memory layout as the underlying
+/// system representation.
+///
+/// [IETF RFC 793]: https://tools.ietf.org/html/rfc793
+/// [`IPv4` address]: Ipv4Addr
+///
+/// # Examples
+///
+/// ```
+/// use std::net::{Ipv4Addr, SocketAddrV4};
+///
+/// let socket = SocketAddrV4::new(Ipv4Addr::new(127, 0, 0, 1), 8080);
+///
+/// assert_eq!("127.0.0.1:8080".parse(), Ok(socket));
+/// assert_eq!(socket.ip(), &Ipv4Addr::new(127, 0, 0, 1));
+/// assert_eq!(socket.port(), 8080);
+/// ```
+#[derive(Copy, Clone, Eq, PartialEq)]
+#[stable(feature = "rust1", since = "1.0.0")]
+pub struct SocketAddrV4 {
+    ip: Ipv4Addr,
+    port: u16,
+}
+
+/// An IPv6 socket address.
+///
+/// IPv6 socket addresses consist of an [`IPv6` address], a 16-bit port number, as well
+/// as fields containing the traffic class, the flow label, and a scope identifier
+/// (see [IETF RFC 2553, Section 3.3] for more details).
+///
+/// See [`SocketAddr`] for a type encompassing both IPv4 and IPv6 socket addresses.
+///
+/// The size of a `SocketAddrV6` struct may vary depending on the target operating
+/// system. Do not assume that this type has the same memory layout as the underlying
+/// system representation.
+///
+/// [IETF RFC 2553, Section 3.3]: https://tools.ietf.org/html/rfc2553#section-3.3
+/// [`IPv6` address]: Ipv6Addr
+///
+/// # Examples
+///
+/// ```
+/// use std::net::{Ipv6Addr, SocketAddrV6};
+///
+/// let socket = SocketAddrV6::new(Ipv6Addr::new(0x2001, 0xdb8, 0, 0, 0, 0, 0, 1), 8080, 0, 0);
+///
+/// assert_eq!("[2001:db8::1]:8080".parse(), Ok(socket));
+/// assert_eq!(socket.ip(), &Ipv6Addr::new(0x2001, 0xdb8, 0, 0, 0, 0, 0, 1));
+/// assert_eq!(socket.port(), 8080);
+/// ```
+#[derive(Copy, Clone, Eq, PartialEq)]
+#[stable(feature = "rust1", since = "1.0.0")]
+pub struct SocketAddrV6 {
+    ip: Ipv6Addr,
+    port: u16,
+    flowinfo: u32,
+    scope_id: u32,
+}
+
+impl SocketAddr {
+    /// Creates a new socket address from an [IP address] and a port number.
+    ///
+    /// [IP address]: IpAddr
+    ///
+    /// # Examples
+    ///
+    /// ```
+    /// use std::net::{IpAddr, Ipv4Addr, SocketAddr};
+    ///
+    /// let socket = SocketAddr::new(IpAddr::V4(Ipv4Addr::new(127, 0, 0, 1)), 8080);
+    /// assert_eq!(socket.ip(), IpAddr::V4(Ipv4Addr::new(127, 0, 0, 1)));
+    /// assert_eq!(socket.port(), 8080);
+    /// ```
+    #[stable(feature = "ip_addr", since = "1.7.0")]
+    #[must_use]
+    #[rustc_const_unstable(feature = "const_socketaddr", issue = "82485")]
+    pub const fn new(ip: IpAddr, port: u16) -> SocketAddr {
+        match ip {
+            IpAddr::V4(a) => SocketAddr::V4(SocketAddrV4::new(a, port)),
+            IpAddr::V6(a) => SocketAddr::V6(SocketAddrV6::new(a, port, 0, 0)),
+        }
+    }
+
+    /// Returns the IP address associated with this socket address.
+    ///
+    /// # Examples
+    ///
+    /// ```
+    /// use std::net::{IpAddr, Ipv4Addr, SocketAddr};
+    ///
+    /// let socket = SocketAddr::new(IpAddr::V4(Ipv4Addr::new(127, 0, 0, 1)), 8080);
+    /// assert_eq!(socket.ip(), IpAddr::V4(Ipv4Addr::new(127, 0, 0, 1)));
+    /// ```
+    #[must_use]
+    #[stable(feature = "ip_addr", since = "1.7.0")]
+    #[rustc_const_unstable(feature = "const_socketaddr", issue = "82485")]
+    pub const fn ip(&self) -> IpAddr {
+        match *self {
+            SocketAddr::V4(ref a) => IpAddr::V4(*a.ip()),
+            SocketAddr::V6(ref a) => IpAddr::V6(*a.ip()),
+        }
+    }
+
+    /// Changes the IP address associated with this socket address.
+    ///
+    /// # Examples
+    ///
+    /// ```
+    /// use std::net::{IpAddr, Ipv4Addr, SocketAddr};
+    ///
+    /// let mut socket = SocketAddr::new(IpAddr::V4(Ipv4Addr::new(127, 0, 0, 1)), 8080);
+    /// socket.set_ip(IpAddr::V4(Ipv4Addr::new(10, 10, 0, 1)));
+    /// assert_eq!(socket.ip(), IpAddr::V4(Ipv4Addr::new(10, 10, 0, 1)));
+    /// ```
+    #[stable(feature = "sockaddr_setters", since = "1.9.0")]
+    pub fn set_ip(&mut self, new_ip: IpAddr) {
+        // `match (*self, new_ip)` would have us mutate a copy of self only to throw it away.
+        match (self, new_ip) {
+            (&mut SocketAddr::V4(ref mut a), IpAddr::V4(new_ip)) => a.set_ip(new_ip),
+            (&mut SocketAddr::V6(ref mut a), IpAddr::V6(new_ip)) => a.set_ip(new_ip),
+            (self_, new_ip) => *self_ = Self::new(new_ip, self_.port()),
+        }
+    }
+
+    /// Returns the port number associated with this socket address.
+    ///
+    /// # Examples
+    ///
+    /// ```
+    /// use std::net::{IpAddr, Ipv4Addr, SocketAddr};
+    ///
+    /// let socket = SocketAddr::new(IpAddr::V4(Ipv4Addr::new(127, 0, 0, 1)), 8080);
+    /// assert_eq!(socket.port(), 8080);
+    /// ```
+    #[must_use]
+    #[stable(feature = "rust1", since = "1.0.0")]
+    #[rustc_const_unstable(feature = "const_socketaddr", issue = "82485")]
+    pub const fn port(&self) -> u16 {
+        match *self {
+            SocketAddr::V4(ref a) => a.port(),
+            SocketAddr::V6(ref a) => a.port(),
+        }
+    }
+
+    /// Changes the port number associated with this socket address.
+    ///
+    /// # Examples
+    ///
+    /// ```
+    /// use std::net::{IpAddr, Ipv4Addr, SocketAddr};
+    ///
+    /// let mut socket = SocketAddr::new(IpAddr::V4(Ipv4Addr::new(127, 0, 0, 1)), 8080);
+    /// socket.set_port(1025);
+    /// assert_eq!(socket.port(), 1025);
+    /// ```
+    #[stable(feature = "sockaddr_setters", since = "1.9.0")]
+    pub fn set_port(&mut self, new_port: u16) {
+        match *self {
+            SocketAddr::V4(ref mut a) => a.set_port(new_port),
+            SocketAddr::V6(ref mut a) => a.set_port(new_port),
+        }
+    }
+
+    /// Returns [`true`] if the [IP address] in this `SocketAddr` is an
+    /// [`IPv4` address], and [`false`] otherwise.
+    ///
+    /// [IP address]: IpAddr
+    /// [`IPv4` address]: IpAddr::V4
+    ///
+    /// # Examples
+    ///
+    /// ```
+    /// use std::net::{IpAddr, Ipv4Addr, SocketAddr};
+    ///
+    /// let socket = SocketAddr::new(IpAddr::V4(Ipv4Addr::new(127, 0, 0, 1)), 8080);
+    /// assert_eq!(socket.is_ipv4(), true);
+    /// assert_eq!(socket.is_ipv6(), false);
+    /// ```
+    #[must_use]
+    #[stable(feature = "sockaddr_checker", since = "1.16.0")]
+    #[rustc_const_unstable(feature = "const_socketaddr", issue = "82485")]
+    pub const fn is_ipv4(&self) -> bool {
+        matches!(*self, SocketAddr::V4(_))
+    }
+
+    /// Returns [`true`] if the [IP address] in this `SocketAddr` is an
+    /// [`IPv6` address], and [`false`] otherwise.
+    ///
+    /// [IP address]: IpAddr
+    /// [`IPv6` address]: IpAddr::V6
+    ///
+    /// # Examples
+    ///
+    /// ```
+    /// use std::net::{IpAddr, Ipv6Addr, SocketAddr};
+    ///
+    /// let socket = SocketAddr::new(IpAddr::V6(Ipv6Addr::new(0, 0, 0, 0, 0, 65535, 0, 1)), 8080);
+    /// assert_eq!(socket.is_ipv4(), false);
+    /// assert_eq!(socket.is_ipv6(), true);
+    /// ```
+    #[must_use]
+    #[stable(feature = "sockaddr_checker", since = "1.16.0")]
+    #[rustc_const_unstable(feature = "const_socketaddr", issue = "82485")]
+    pub const fn is_ipv6(&self) -> bool {
+        matches!(*self, SocketAddr::V6(_))
+    }
+}
+
+impl SocketAddrV4 {
+    /// Creates a new socket address from an [`IPv4` address] and a port number.
+    ///
+    /// [`IPv4` address]: Ipv4Addr
+    ///
+    /// # Examples
+    ///
+    /// ```
+    /// use std::net::{SocketAddrV4, Ipv4Addr};
+    ///
+    /// let socket = SocketAddrV4::new(Ipv4Addr::new(127, 0, 0, 1), 8080);
+    /// ```
+    #[stable(feature = "rust1", since = "1.0.0")]
+    #[must_use]
+    #[rustc_const_unstable(feature = "const_socketaddr", issue = "82485")]
+    pub const fn new(ip: Ipv4Addr, port: u16) -> SocketAddrV4 {
+        SocketAddrV4 { ip, port }
+    }
+
+    /// Returns the IP address associated with this socket address.
+    ///
+    /// # Examples
+    ///
+    /// ```
+    /// use std::net::{SocketAddrV4, Ipv4Addr};
+    ///
+    /// let socket = SocketAddrV4::new(Ipv4Addr::new(127, 0, 0, 1), 8080);
+    /// assert_eq!(socket.ip(), &Ipv4Addr::new(127, 0, 0, 1));
+    /// ```
+    #[must_use]
+    #[stable(feature = "rust1", since = "1.0.0")]
+    #[rustc_const_unstable(feature = "const_socketaddr", issue = "82485")]
+    pub const fn ip(&self) -> &Ipv4Addr {
+        &self.ip
+    }
+
+    /// Changes the IP address associated with this socket address.
+    ///
+    /// # Examples
+    ///
+    /// ```
+    /// use std::net::{SocketAddrV4, Ipv4Addr};
+    ///
+    /// let mut socket = SocketAddrV4::new(Ipv4Addr::new(127, 0, 0, 1), 8080);
+    /// socket.set_ip(Ipv4Addr::new(192, 168, 0, 1));
+    /// assert_eq!(socket.ip(), &Ipv4Addr::new(192, 168, 0, 1));
+    /// ```
+    #[stable(feature = "sockaddr_setters", since = "1.9.0")]
+    pub fn set_ip(&mut self, new_ip: Ipv4Addr) {
+        self.ip = new_ip;
+    }
+
+    /// Returns the port number associated with this socket address.
+    ///
+    /// # Examples
+    ///
+    /// ```
+    /// use std::net::{SocketAddrV4, Ipv4Addr};
+    ///
+    /// let socket = SocketAddrV4::new(Ipv4Addr::new(127, 0, 0, 1), 8080);
+    /// assert_eq!(socket.port(), 8080);
+    /// ```
+    #[must_use]
+    #[stable(feature = "rust1", since = "1.0.0")]
+    #[rustc_const_unstable(feature = "const_socketaddr", issue = "82485")]
+    pub const fn port(&self) -> u16 {
+        self.port
+    }
+
+    /// Changes the port number associated with this socket address.
+    ///
+    /// # Examples
+    ///
+    /// ```
+    /// use std::net::{SocketAddrV4, Ipv4Addr};
+    ///
+    /// let mut socket = SocketAddrV4::new(Ipv4Addr::new(127, 0, 0, 1), 8080);
+    /// socket.set_port(4242);
+    /// assert_eq!(socket.port(), 4242);
+    /// ```
+    #[stable(feature = "sockaddr_setters", since = "1.9.0")]
+    pub fn set_port(&mut self, new_port: u16) {
+        self.port = new_port;
+    }
+}
+
+impl SocketAddrV6 {
+    /// Creates a new socket address from an [`IPv6` address], a 16-bit port number,
+    /// and the `flowinfo` and `scope_id` fields.
+    ///
+    /// For more information on the meaning and layout of the `flowinfo` and `scope_id`
+    /// parameters, see [IETF RFC 2553, Section 3.3].
+    ///
+    /// [IETF RFC 2553, Section 3.3]: https://tools.ietf.org/html/rfc2553#section-3.3
+    /// [`IPv6` address]: Ipv6Addr
+    ///
+    /// # Examples
+    ///
+    /// ```
+    /// use std::net::{SocketAddrV6, Ipv6Addr};
+    ///
+    /// let socket = SocketAddrV6::new(Ipv6Addr::new(0, 0, 0, 0, 0, 0, 0, 1), 8080, 0, 0);
+    /// ```
+    #[stable(feature = "rust1", since = "1.0.0")]
+    #[must_use]
+    #[rustc_const_unstable(feature = "const_socketaddr", issue = "82485")]
+    pub const fn new(ip: Ipv6Addr, port: u16, flowinfo: u32, scope_id: u32) -> SocketAddrV6 {
+        SocketAddrV6 { ip, port, flowinfo, scope_id }
+    }
+
+    /// Returns the IP address associated with this socket address.
+    ///
+    /// # Examples
+    ///
+    /// ```
+    /// use std::net::{SocketAddrV6, Ipv6Addr};
+    ///
+    /// let socket = SocketAddrV6::new(Ipv6Addr::new(0, 0, 0, 0, 0, 0, 0, 1), 8080, 0, 0);
+    /// assert_eq!(socket.ip(), &Ipv6Addr::new(0, 0, 0, 0, 0, 0, 0, 1));
+    /// ```
+    #[must_use]
+    #[stable(feature = "rust1", since = "1.0.0")]
+    #[rustc_const_unstable(feature = "const_socketaddr", issue = "82485")]
+    pub const fn ip(&self) -> &Ipv6Addr {
+        &self.ip
+    }
+
+    /// Changes the IP address associated with this socket address.
+    ///
+    /// # Examples
+    ///
+    /// ```
+    /// use std::net::{SocketAddrV6, Ipv6Addr};
+    ///
+    /// let mut socket = SocketAddrV6::new(Ipv6Addr::new(0, 0, 0, 0, 0, 0, 0, 1), 8080, 0, 0);
+    /// socket.set_ip(Ipv6Addr::new(76, 45, 0, 0, 0, 0, 0, 0));
+    /// assert_eq!(socket.ip(), &Ipv6Addr::new(76, 45, 0, 0, 0, 0, 0, 0));
+    /// ```
+    #[stable(feature = "sockaddr_setters", since = "1.9.0")]
+    pub fn set_ip(&mut self, new_ip: Ipv6Addr) {
+        self.ip = new_ip;
+    }
+
+    /// Returns the port number associated with this socket address.
+    ///
+    /// # Examples
+    ///
+    /// ```
+    /// use std::net::{SocketAddrV6, Ipv6Addr};
+    ///
+    /// let socket = SocketAddrV6::new(Ipv6Addr::new(0, 0, 0, 0, 0, 0, 0, 1), 8080, 0, 0);
+    /// assert_eq!(socket.port(), 8080);
+    /// ```
+    #[must_use]
+    #[stable(feature = "rust1", since = "1.0.0")]
+    #[rustc_const_unstable(feature = "const_socketaddr", issue = "82485")]
+    pub const fn port(&self) -> u16 {
+        self.port
+    }
+
+    /// Changes the port number associated with this socket address.
+    ///
+    /// # Examples
+    ///
+    /// ```
+    /// use std::net::{SocketAddrV6, Ipv6Addr};
+    ///
+    /// let mut socket = SocketAddrV6::new(Ipv6Addr::new(0, 0, 0, 0, 0, 0, 0, 1), 8080, 0, 0);
+    /// socket.set_port(4242);
+    /// assert_eq!(socket.port(), 4242);
+    /// ```
+    #[stable(feature = "sockaddr_setters", since = "1.9.0")]
+    pub fn set_port(&mut self, new_port: u16) {
+        self.port = new_port;
+    }
+
+    /// Returns the flow information associated with this address.
+    ///
+    /// This information corresponds to the `sin6_flowinfo` field in C's `netinet/in.h`,
+    /// as specified in [IETF RFC 2553, Section 3.3].
+    /// It combines information about the flow label and the traffic class as specified
+    /// in [IETF RFC 2460], respectively [Section 6] and [Section 7].
+    ///
+    /// [IETF RFC 2553, Section 3.3]: https://tools.ietf.org/html/rfc2553#section-3.3
+    /// [IETF RFC 2460]: https://tools.ietf.org/html/rfc2460
+    /// [Section 6]: https://tools.ietf.org/html/rfc2460#section-6
+    /// [Section 7]: https://tools.ietf.org/html/rfc2460#section-7
+    ///
+    /// # Examples
+    ///
+    /// ```
+    /// use std::net::{SocketAddrV6, Ipv6Addr};
+    ///
+    /// let socket = SocketAddrV6::new(Ipv6Addr::new(0, 0, 0, 0, 0, 0, 0, 1), 8080, 10, 0);
+    /// assert_eq!(socket.flowinfo(), 10);
+    /// ```
+    #[must_use]
+    #[stable(feature = "rust1", since = "1.0.0")]
+    #[rustc_const_unstable(feature = "const_socketaddr", issue = "82485")]
+    pub const fn flowinfo(&self) -> u32 {
+        self.flowinfo
+    }
+
+    /// Changes the flow information associated with this socket address.
+    ///
+    /// See [`SocketAddrV6::flowinfo`]'s documentation for more details.
+    ///
+    /// # Examples
+    ///
+    /// ```
+    /// use std::net::{SocketAddrV6, Ipv6Addr};
+    ///
+    /// let mut socket = SocketAddrV6::new(Ipv6Addr::new(0, 0, 0, 0, 0, 0, 0, 1), 8080, 10, 0);
+    /// socket.set_flowinfo(56);
+    /// assert_eq!(socket.flowinfo(), 56);
+    /// ```
+    #[stable(feature = "sockaddr_setters", since = "1.9.0")]
+    pub fn set_flowinfo(&mut self, new_flowinfo: u32) {
+        self.flowinfo = new_flowinfo;
+    }
+
+    /// Returns the scope ID associated with this address.
+    ///
+    /// This information corresponds to the `sin6_scope_id` field in C's `netinet/in.h`,
+    /// as specified in [IETF RFC 2553, Section 3.3].
+    ///
+    /// [IETF RFC 2553, Section 3.3]: https://tools.ietf.org/html/rfc2553#section-3.3
+    ///
+    /// # Examples
+    ///
+    /// ```
+    /// use std::net::{SocketAddrV6, Ipv6Addr};
+    ///
+    /// let socket = SocketAddrV6::new(Ipv6Addr::new(0, 0, 0, 0, 0, 0, 0, 1), 8080, 0, 78);
+    /// assert_eq!(socket.scope_id(), 78);
+    /// ```
+    #[must_use]
+    #[stable(feature = "rust1", since = "1.0.0")]
+    #[rustc_const_unstable(feature = "const_socketaddr", issue = "82485")]
+    pub const fn scope_id(&self) -> u32 {
+        self.scope_id
+    }
+
+    /// Changes the scope ID associated with this socket address.
+    ///
+    /// See [`SocketAddrV6::scope_id`]'s documentation for more details.
+    ///
+    /// # Examples
+    ///
+    /// ```
+    /// use std::net::{SocketAddrV6, Ipv6Addr};
+    ///
+    /// let mut socket = SocketAddrV6::new(Ipv6Addr::new(0, 0, 0, 0, 0, 0, 0, 1), 8080, 0, 78);
+    /// socket.set_scope_id(42);
+    /// assert_eq!(socket.scope_id(), 42);
+    /// ```
+    #[stable(feature = "sockaddr_setters", since = "1.9.0")]
+    pub fn set_scope_id(&mut self, new_scope_id: u32) {
+        self.scope_id = new_scope_id;
+    }
+}
+
+impl FromInner<c::sockaddr_in> for SocketAddrV4 {
+    fn from_inner(addr: c::sockaddr_in) -> SocketAddrV4 {
+        SocketAddrV4 { ip: Ipv4Addr::from_inner(addr.sin_addr), port: u16::from_be(addr.sin_port) }
+    }
+}
+
+impl FromInner<c::sockaddr_in6> for SocketAddrV6 {
+    fn from_inner(addr: c::sockaddr_in6) -> SocketAddrV6 {
+        SocketAddrV6 {
+            ip: Ipv6Addr::from_inner(addr.sin6_addr),
+            port: u16::from_be(addr.sin6_port),
+            flowinfo: addr.sin6_flowinfo,
+            scope_id: addr.sin6_scope_id,
+        }
+    }
+}
+
+impl IntoInner<c::sockaddr_in> for SocketAddrV4 {
+    fn into_inner(self) -> c::sockaddr_in {
+        c::sockaddr_in {
+            sin_family: c::AF_INET as c::sa_family_t,
+            sin_port: self.port.to_be(),
+            sin_addr: self.ip.into_inner(),
+            ..unsafe { mem::zeroed() }
+        }
+    }
+}
+
+impl IntoInner<c::sockaddr_in6> for SocketAddrV6 {
+    fn into_inner(self) -> c::sockaddr_in6 {
+        c::sockaddr_in6 {
+            sin6_family: c::AF_INET6 as c::sa_family_t,
+            sin6_port: self.port.to_be(),
+            sin6_addr: self.ip.into_inner(),
+            sin6_flowinfo: self.flowinfo,
+            sin6_scope_id: self.scope_id,
+            ..unsafe { mem::zeroed() }
+        }
+    }
+}
+
+#[stable(feature = "ip_from_ip", since = "1.16.0")]
+impl From<SocketAddrV4> for SocketAddr {
+    /// Converts a [`SocketAddrV4`] into a [`SocketAddr::V4`].
+    fn from(sock4: SocketAddrV4) -> SocketAddr {
+        SocketAddr::V4(sock4)
+    }
+}
+
+#[stable(feature = "ip_from_ip", since = "1.16.0")]
+impl From<SocketAddrV6> for SocketAddr {
+    /// Converts a [`SocketAddrV6`] into a [`SocketAddr::V6`].
+    fn from(sock6: SocketAddrV6) -> SocketAddr {
+        SocketAddr::V6(sock6)
+    }
+}
+
+#[stable(feature = "addr_from_into_ip", since = "1.17.0")]
+impl<I: Into<IpAddr>> From<(I, u16)> for SocketAddr {
+    /// Converts a tuple struct (Into<[`IpAddr`]>, `u16`) into a [`SocketAddr`].
+    ///
+    /// This conversion creates a [`SocketAddr::V4`] for an [`IpAddr::V4`]
+    /// and creates a [`SocketAddr::V6`] for an [`IpAddr::V6`].
+    ///
+    /// `u16` is treated as port of the newly created [`SocketAddr`].
+    fn from(pieces: (I, u16)) -> SocketAddr {
+        SocketAddr::new(pieces.0.into(), pieces.1)
+    }
+}
+
+#[stable(feature = "rust1", since = "1.0.0")]
+impl fmt::Display for SocketAddr {
+    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
+        match *self {
+            SocketAddr::V4(ref a) => a.fmt(f),
+            SocketAddr::V6(ref a) => a.fmt(f),
+        }
+    }
+}
+
+#[stable(feature = "rust1", since = "1.0.0")]
+impl fmt::Debug for SocketAddr {
+    fn fmt(&self, fmt: &mut fmt::Formatter<'_>) -> fmt::Result {
+        fmt::Display::fmt(self, fmt)
+    }
+}
+
+#[stable(feature = "rust1", since = "1.0.0")]
+impl fmt::Display for SocketAddrV4 {
+    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
+        // Fast path: if there's no alignment stuff, write to the output buffer
+        // directly
+        if f.precision().is_none() && f.width().is_none() {
+            write!(f, "{}:{}", self.ip(), self.port())
+        } else {
+            const IPV4_SOCKET_BUF_LEN: usize = (3 * 4)  // the segments
+                + 3  // the separators
+                + 1 + 5; // the port
+            let mut buf = [0; IPV4_SOCKET_BUF_LEN];
+            let mut buf_slice = &mut buf[..];
+
+            // Unwrap is fine because writing to a sufficiently-sized
+            // buffer is infallible
+            write!(buf_slice, "{}:{}", self.ip(), self.port()).unwrap();
+            let len = IPV4_SOCKET_BUF_LEN - buf_slice.len();
+
+            // This unsafe is OK because we know what is being written to the buffer
+            let buf = unsafe { crate::str::from_utf8_unchecked(&buf[..len]) };
+            f.pad(buf)
+        }
+    }
+}
+
+#[stable(feature = "rust1", since = "1.0.0")]
+impl fmt::Debug for SocketAddrV4 {
+    fn fmt(&self, fmt: &mut fmt::Formatter<'_>) -> fmt::Result {
+        fmt::Display::fmt(self, fmt)
+    }
+}
+
+#[stable(feature = "rust1", since = "1.0.0")]
+impl fmt::Display for SocketAddrV6 {
+    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
+        // Fast path: if there's no alignment stuff, write to the output
+        // buffer directly
+        if f.precision().is_none() && f.width().is_none() {
+            match self.scope_id() {
+                0 => write!(f, "[{}]:{}", self.ip(), self.port()),
+                scope_id => write!(f, "[{}%{}]:{}", self.ip(), scope_id, self.port()),
+            }
+        } else {
+            const IPV6_SOCKET_BUF_LEN: usize = (4 * 8)  // The address
+            + 7  // The colon separators
+            + 2  // The brackets
+            + 1 + 10 // The scope id
+            + 1 + 5; // The port
+
+            let mut buf = [0; IPV6_SOCKET_BUF_LEN];
+            let mut buf_slice = &mut buf[..];
+
+            match self.scope_id() {
+                0 => write!(buf_slice, "[{}]:{}", self.ip(), self.port()),
+                scope_id => write!(buf_slice, "[{}%{}]:{}", self.ip(), scope_id, self.port()),
+            }
+            // Unwrap is fine because writing to a sufficiently-sized
+            // buffer is infallible
+            .unwrap();
+            let len = IPV6_SOCKET_BUF_LEN - buf_slice.len();
+
+            // This unsafe is OK because we know what is being written to the buffer
+            let buf = unsafe { crate::str::from_utf8_unchecked(&buf[..len]) };
+            f.pad(buf)
+        }
+    }
+}
+
+#[stable(feature = "rust1", since = "1.0.0")]
+impl fmt::Debug for SocketAddrV6 {
+    fn fmt(&self, fmt: &mut fmt::Formatter<'_>) -> fmt::Result {
+        fmt::Display::fmt(self, fmt)
+    }
+}
+
+#[stable(feature = "socketaddr_ordering", since = "1.45.0")]
+impl PartialOrd for SocketAddrV4 {
+    fn partial_cmp(&self, other: &SocketAddrV4) -> Option<Ordering> {
+        Some(self.cmp(other))
+    }
+}
+
+#[stable(feature = "socketaddr_ordering", since = "1.45.0")]
+impl PartialOrd for SocketAddrV6 {
+    fn partial_cmp(&self, other: &SocketAddrV6) -> Option<Ordering> {
+        Some(self.cmp(other))
+    }
+}
+
+#[stable(feature = "socketaddr_ordering", since = "1.45.0")]
+impl Ord for SocketAddrV4 {
+    fn cmp(&self, other: &SocketAddrV4) -> Ordering {
+        self.ip().cmp(other.ip()).then(self.port().cmp(&other.port()))
+    }
+}
+
+#[stable(feature = "socketaddr_ordering", since = "1.45.0")]
+impl Ord for SocketAddrV6 {
+    fn cmp(&self, other: &SocketAddrV6) -> Ordering {
+        self.ip().cmp(other.ip()).then(self.port().cmp(&other.port()))
+    }
+}
+
+#[stable(feature = "rust1", since = "1.0.0")]
+impl hash::Hash for SocketAddrV4 {
+    fn hash<H: hash::Hasher>(&self, s: &mut H) {
+        (self.port, self.ip).hash(s)
+    }
+}
+#[stable(feature = "rust1", since = "1.0.0")]
+impl hash::Hash for SocketAddrV6 {
+    fn hash<H: hash::Hasher>(&self, s: &mut H) {
+        (self.port, &self.ip, self.flowinfo, self.scope_id).hash(s)
+    }
+}
+
+/// A trait for objects which can be converted or resolved to one or more
+/// [`SocketAddr`] values.
+///
+/// This trait is used for generic address resolution when constructing network
+/// objects. By default it is implemented for the following types:
+///
+///  * [`SocketAddr`]: [`to_socket_addrs`] is the identity function.
+///
+///  * [`SocketAddrV4`], [`SocketAddrV6`], <code>([IpAddr], [u16])</code>,
+///    <code>([Ipv4Addr], [u16])</code>, <code>([Ipv6Addr], [u16])</code>:
+///    [`to_socket_addrs`] constructs a [`SocketAddr`] trivially.
+///
+///  * <code>(&[str], [u16])</code>: <code>&[str]</code> should be either a string representation
+///    of an [`IpAddr`] address as expected by [`FromStr`] implementation or a host
+///    name. [`u16`] is the port number.
+///
+///  * <code>&[str]</code>: the string should be either a string representation of a
+///    [`SocketAddr`] as expected by its [`FromStr`] implementation or a string like
+///    `<host_name>:<port>` pair where `<port>` is a [`u16`] value.
+///
+/// This trait allows constructing network objects like [`TcpStream`] or
+/// [`UdpSocket`] easily with values of various types for the bind/connection
+/// address. It is needed because sometimes one type is more appropriate than
+/// the other: for simple uses a string like `"localhost:12345"` is much nicer
+/// than manual construction of the corresponding [`SocketAddr`], but sometimes
+/// [`SocketAddr`] value is *the* main source of the address, and converting it to
+/// some other type (e.g., a string) just for it to be converted back to
+/// [`SocketAddr`] in constructor methods is pointless.
+///
+/// Addresses returned by the operating system that are not IP addresses are
+/// silently ignored.
+///
+/// [`FromStr`]: crate::str::FromStr "std::str::FromStr"
+/// [`TcpStream`]: crate::net::TcpStream "net::TcpStream"
+/// [`to_socket_addrs`]: ToSocketAddrs::to_socket_addrs
+/// [`UdpSocket`]: crate::net::UdpSocket "net::UdpSocket"
+///
+/// # Examples
+///
+/// Creating a [`SocketAddr`] iterator that yields one item:
+///
+/// ```
+/// use std::net::{ToSocketAddrs, SocketAddr};
+///
+/// let addr = SocketAddr::from(([127, 0, 0, 1], 443));
+/// let mut addrs_iter = addr.to_socket_addrs().unwrap();
+///
+/// assert_eq!(Some(addr), addrs_iter.next());
+/// assert!(addrs_iter.next().is_none());
+/// ```
+///
+/// Creating a [`SocketAddr`] iterator from a hostname:
+///
+/// ```no_run
+/// use std::net::{SocketAddr, ToSocketAddrs};
+///
+/// // assuming 'localhost' resolves to 127.0.0.1
+/// let mut addrs_iter = "localhost:443".to_socket_addrs().unwrap();
+/// assert_eq!(addrs_iter.next(), Some(SocketAddr::from(([127, 0, 0, 1], 443))));
+/// assert!(addrs_iter.next().is_none());
+///
+/// // assuming 'foo' does not resolve
+/// assert!("foo:443".to_socket_addrs().is_err());
+/// ```
+///
+/// Creating a [`SocketAddr`] iterator that yields multiple items:
+///
+/// ```
+/// use std::net::{SocketAddr, ToSocketAddrs};
+///
+/// let addr1 = SocketAddr::from(([0, 0, 0, 0], 80));
+/// let addr2 = SocketAddr::from(([127, 0, 0, 1], 443));
+/// let addrs = vec![addr1, addr2];
+///
+/// let mut addrs_iter = (&addrs[..]).to_socket_addrs().unwrap();
+///
+/// assert_eq!(Some(addr1), addrs_iter.next());
+/// assert_eq!(Some(addr2), addrs_iter.next());
+/// assert!(addrs_iter.next().is_none());
+/// ```
+///
+/// Attempting to create a [`SocketAddr`] iterator from an improperly formatted
+/// socket address `&str` (missing the port):
+///
+/// ```
+/// use std::io;
+/// use std::net::ToSocketAddrs;
+///
+/// let err = "127.0.0.1".to_socket_addrs().unwrap_err();
+/// assert_eq!(err.kind(), io::ErrorKind::InvalidInput);
+/// ```
+///
+/// [`TcpStream::connect`] is an example of an function that utilizes
+/// `ToSocketAddrs` as a trait bound on its parameter in order to accept
+/// different types:
+///
+/// ```no_run
+/// use std::net::{TcpStream, Ipv4Addr};
+///
+/// let stream = TcpStream::connect(("127.0.0.1", 443));
+/// // or
+/// let stream = TcpStream::connect("127.0.0.1:443");
+/// // or
+/// let stream = TcpStream::connect((Ipv4Addr::new(127, 0, 0, 1), 443));
+/// ```
+///
+/// [`TcpStream::connect`]: crate::net::TcpStream::connect
+#[stable(feature = "rust1", since = "1.0.0")]
+pub trait ToSocketAddrs {
+    /// Returned iterator over socket addresses which this type may correspond
+    /// to.
+    #[stable(feature = "rust1", since = "1.0.0")]
+    type Iter: Iterator<Item = SocketAddr>;
+
+    /// Converts this object to an iterator of resolved [`SocketAddr`]s.
+    ///
+    /// The returned iterator might not actually yield any values depending on the
+    /// outcome of any resolution performed.
+    ///
+    /// Note that this function may block the current thread while resolution is
+    /// performed.
+    #[stable(feature = "rust1", since = "1.0.0")]
+    fn to_socket_addrs(&self) -> io::Result<Self::Iter>;
+}
+
+#[stable(feature = "rust1", since = "1.0.0")]
+impl ToSocketAddrs for SocketAddr {
+    type Iter = option::IntoIter<SocketAddr>;
+    fn to_socket_addrs(&self) -> io::Result<option::IntoIter<SocketAddr>> {
+        Ok(Some(*self).into_iter())
+    }
+}
+
+#[stable(feature = "rust1", since = "1.0.0")]
+impl ToSocketAddrs for SocketAddrV4 {
+    type Iter = option::IntoIter<SocketAddr>;
+    fn to_socket_addrs(&self) -> io::Result<option::IntoIter<SocketAddr>> {
+        SocketAddr::V4(*self).to_socket_addrs()
+    }
+}
+
+#[stable(feature = "rust1", since = "1.0.0")]
+impl ToSocketAddrs for SocketAddrV6 {
+    type Iter = option::IntoIter<SocketAddr>;
+    fn to_socket_addrs(&self) -> io::Result<option::IntoIter<SocketAddr>> {
+        SocketAddr::V6(*self).to_socket_addrs()
+    }
+}
+
+#[stable(feature = "rust1", since = "1.0.0")]
+impl ToSocketAddrs for (IpAddr, u16) {
+    type Iter = option::IntoIter<SocketAddr>;
+    fn to_socket_addrs(&self) -> io::Result<option::IntoIter<SocketAddr>> {
+        let (ip, port) = *self;
+        match ip {
+            IpAddr::V4(ref a) => (*a, port).to_socket_addrs(),
+            IpAddr::V6(ref a) => (*a, port).to_socket_addrs(),
+        }
+    }
+}
+
+#[stable(feature = "rust1", since = "1.0.0")]
+impl ToSocketAddrs for (Ipv4Addr, u16) {
+    type Iter = option::IntoIter<SocketAddr>;
+    fn to_socket_addrs(&self) -> io::Result<option::IntoIter<SocketAddr>> {
+        let (ip, port) = *self;
+        SocketAddrV4::new(ip, port).to_socket_addrs()
+    }
+}
+
+#[stable(feature = "rust1", since = "1.0.0")]
+impl ToSocketAddrs for (Ipv6Addr, u16) {
+    type Iter = option::IntoIter<SocketAddr>;
+    fn to_socket_addrs(&self) -> io::Result<option::IntoIter<SocketAddr>> {
+        let (ip, port) = *self;
+        SocketAddrV6::new(ip, port, 0, 0).to_socket_addrs()
+    }
+}
+
+fn resolve_socket_addr(lh: LookupHost) -> io::Result<vec::IntoIter<SocketAddr>> {
+    let p = lh.port();
+    let v: Vec<_> = lh
+        .map(|mut a| {
+            a.set_port(p);
+            a
+        })
+        .collect();
+    Ok(v.into_iter())
+}
+
+#[stable(feature = "rust1", since = "1.0.0")]
+impl ToSocketAddrs for (&str, u16) {
+    type Iter = vec::IntoIter<SocketAddr>;
+    fn to_socket_addrs(&self) -> io::Result<vec::IntoIter<SocketAddr>> {
+        let (host, port) = *self;
+
+        // try to parse the host as a regular IP address first
+        if let Ok(addr) = host.parse::<Ipv4Addr>() {
+            let addr = SocketAddrV4::new(addr, port);
+            return Ok(vec![SocketAddr::V4(addr)].into_iter());
+        }
+        if let Ok(addr) = host.parse::<Ipv6Addr>() {
+            let addr = SocketAddrV6::new(addr, port, 0, 0);
+            return Ok(vec![SocketAddr::V6(addr)].into_iter());
+        }
+
+        resolve_socket_addr((host, port).try_into()?)
+    }
+}
+
+#[stable(feature = "string_u16_to_socket_addrs", since = "1.46.0")]
+impl ToSocketAddrs for (String, u16) {
+    type Iter = vec::IntoIter<SocketAddr>;
+    fn to_socket_addrs(&self) -> io::Result<vec::IntoIter<SocketAddr>> {
+        (&*self.0, self.1).to_socket_addrs()
+    }
+}
+
+// accepts strings like 'localhost:12345'
+#[stable(feature = "rust1", since = "1.0.0")]
+impl ToSocketAddrs for str {
+    type Iter = vec::IntoIter<SocketAddr>;
+    fn to_socket_addrs(&self) -> io::Result<vec::IntoIter<SocketAddr>> {
+        // try to parse as a regular SocketAddr first
+        if let Ok(addr) = self.parse() {
+            return Ok(vec![addr].into_iter());
+        }
+
+        resolve_socket_addr(self.try_into()?)
+    }
+}
+
+#[stable(feature = "slice_to_socket_addrs", since = "1.8.0")]
+impl<'a> ToSocketAddrs for &'a [SocketAddr] {
+    type Iter = iter::Cloned<slice::Iter<'a, SocketAddr>>;
+
+    fn to_socket_addrs(&self) -> io::Result<Self::Iter> {
+        Ok(self.iter().cloned())
+    }
+}
+
+#[stable(feature = "rust1", since = "1.0.0")]
+impl<T: ToSocketAddrs + ?Sized> ToSocketAddrs for &T {
+    type Iter = T::Iter;
+    fn to_socket_addrs(&self) -> io::Result<T::Iter> {
+        (**self).to_socket_addrs()
+    }
+}
+
+#[stable(feature = "string_to_socket_addrs", since = "1.16.0")]
+impl ToSocketAddrs for String {
+    type Iter = vec::IntoIter<SocketAddr>;
+    fn to_socket_addrs(&self) -> io::Result<vec::IntoIter<SocketAddr>> {
+        (&**self).to_socket_addrs()
+    }
+}
diff --git a/library/std/src/net/addr/tests.rs b/library/std/src/net/addr/tests.rs
new file mode 100644
index 000000000..585a17451
--- /dev/null
+++ b/library/std/src/net/addr/tests.rs
@@ -0,0 +1,237 @@
+use crate::net::test::{sa4, sa6, tsa};
+use crate::net::*;
+
+#[test]
+fn to_socket_addr_ipaddr_u16() {
+    let a = Ipv4Addr::new(77, 88, 21, 11);
+    let p = 12345;
+    let e = SocketAddr::V4(SocketAddrV4::new(a, p));
+    assert_eq!(Ok(vec![e]), tsa((a, p)));
+}
+
+#[test]
+fn to_socket_addr_str_u16() {
+    let a = sa4(Ipv4Addr::new(77, 88, 21, 11), 24352);
+    assert_eq!(Ok(vec![a]), tsa(("77.88.21.11", 24352)));
+
+    let a = sa6(Ipv6Addr::new(0x2a02, 0x6b8, 0, 1, 0, 0, 0, 1), 53);
+    assert_eq!(Ok(vec![a]), tsa(("2a02:6b8:0:1::1", 53)));
+
+    let a = sa4(Ipv4Addr::new(127, 0, 0, 1), 23924);
+    #[cfg(not(target_env = "sgx"))]
+    assert!(tsa(("localhost", 23924)).unwrap().contains(&a));
+    #[cfg(target_env = "sgx")]
+    let _ = a;
+}
+
+#[test]
+fn to_socket_addr_str() {
+    let a = sa4(Ipv4Addr::new(77, 88, 21, 11), 24352);
+    assert_eq!(Ok(vec![a]), tsa("77.88.21.11:24352"));
+
+    let a = sa6(Ipv6Addr::new(0x2a02, 0x6b8, 0, 1, 0, 0, 0, 1), 53);
+    assert_eq!(Ok(vec![a]), tsa("[2a02:6b8:0:1::1]:53"));
+
+    let a = sa4(Ipv4Addr::new(127, 0, 0, 1), 23924);
+    #[cfg(not(target_env = "sgx"))]
+    assert!(tsa("localhost:23924").unwrap().contains(&a));
+    #[cfg(target_env = "sgx")]
+    let _ = a;
+}
+
+#[test]
+fn to_socket_addr_string() {
+    let a = sa4(Ipv4Addr::new(77, 88, 21, 11), 24352);
+    assert_eq!(Ok(vec![a]), tsa(&*format!("{}:{}", "77.88.21.11", "24352")));
+    assert_eq!(Ok(vec![a]), tsa(&format!("{}:{}", "77.88.21.11", "24352")));
+    assert_eq!(Ok(vec![a]), tsa(format!("{}:{}", "77.88.21.11", "24352")));
+
+    let s = format!("{}:{}", "77.88.21.11", "24352");
+    assert_eq!(Ok(vec![a]), tsa(s));
+    // s has been moved into the tsa call
+}
+
+#[test]
+fn bind_udp_socket_bad() {
+    // rust-lang/rust#53957: This is a regression test for a parsing problem
+    // discovered as part of issue rust-lang/rust#23076, where we were
+    // incorrectly parsing invalid input and then that would result in a
+    // successful `UdpSocket` binding when we would expect failure.
+    //
+    // At one time, this test was written as a call to `tsa` with
+    // INPUT_23076. However, that structure yields an unreliable test,
+    // because it ends up passing junk input to the DNS server, and some DNS
+    // servers will respond with `Ok` to such input, with the ip address of
+    // the DNS server itself.
+    //
+    // This form of the test is more robust: even when the DNS server
+    // returns its own address, it is still an error to bind a UDP socket to
+    // a non-local address, and so we still get an error here in that case.
+
+    const INPUT_23076: &str = "1200::AB00:1234::2552:7777:1313:34300";
+
+    assert!(crate::net::UdpSocket::bind(INPUT_23076).is_err())
+}
+
+#[test]
+fn set_ip() {
+    fn ip4(low: u8) -> Ipv4Addr {
+        Ipv4Addr::new(77, 88, 21, low)
+    }
+    fn ip6(low: u16) -> Ipv6Addr {
+        Ipv6Addr::new(0x2a02, 0x6b8, 0, 1, 0, 0, 0, low)
+    }
+
+    let mut v4 = SocketAddrV4::new(ip4(11), 80);
+    assert_eq!(v4.ip(), &ip4(11));
+    v4.set_ip(ip4(12));
+    assert_eq!(v4.ip(), &ip4(12));
+
+    let mut addr = SocketAddr::V4(v4);
+    assert_eq!(addr.ip(), IpAddr::V4(ip4(12)));
+    addr.set_ip(IpAddr::V4(ip4(13)));
+    assert_eq!(addr.ip(), IpAddr::V4(ip4(13)));
+    addr.set_ip(IpAddr::V6(ip6(14)));
+    assert_eq!(addr.ip(), IpAddr::V6(ip6(14)));
+
+    let mut v6 = SocketAddrV6::new(ip6(1), 80, 0, 0);
+    assert_eq!(v6.ip(), &ip6(1));
+    v6.set_ip(ip6(2));
+    assert_eq!(v6.ip(), &ip6(2));
+
+    let mut addr = SocketAddr::V6(v6);
+    assert_eq!(addr.ip(), IpAddr::V6(ip6(2)));
+    addr.set_ip(IpAddr::V6(ip6(3)));
+    assert_eq!(addr.ip(), IpAddr::V6(ip6(3)));
+    addr.set_ip(IpAddr::V4(ip4(4)));
+    assert_eq!(addr.ip(), IpAddr::V4(ip4(4)));
+}
+
+#[test]
+fn set_port() {
+    let mut v4 = SocketAddrV4::new(Ipv4Addr::new(77, 88, 21, 11), 80);
+    assert_eq!(v4.port(), 80);
+    v4.set_port(443);
+    assert_eq!(v4.port(), 443);
+
+    let mut addr = SocketAddr::V4(v4);
+    assert_eq!(addr.port(), 443);
+    addr.set_port(8080);
+    assert_eq!(addr.port(), 8080);
+
+    let mut v6 = SocketAddrV6::new(Ipv6Addr::new(0x2a02, 0x6b8, 0, 1, 0, 0, 0, 1), 80, 0, 0);
+    assert_eq!(v6.port(), 80);
+    v6.set_port(443);
+    assert_eq!(v6.port(), 443);
+
+    let mut addr = SocketAddr::V6(v6);
+    assert_eq!(addr.port(), 443);
+    addr.set_port(8080);
+    assert_eq!(addr.port(), 8080);
+}
+
+#[test]
+fn set_flowinfo() {
+    let mut v6 = SocketAddrV6::new(Ipv6Addr::new(0x2a02, 0x6b8, 0, 1, 0, 0, 0, 1), 80, 10, 0);
+    assert_eq!(v6.flowinfo(), 10);
+    v6.set_flowinfo(20);
+    assert_eq!(v6.flowinfo(), 20);
+}
+
+#[test]
+fn set_scope_id() {
+    let mut v6 = SocketAddrV6::new(Ipv6Addr::new(0x2a02, 0x6b8, 0, 1, 0, 0, 0, 1), 80, 0, 10);
+    assert_eq!(v6.scope_id(), 10);
+    v6.set_scope_id(20);
+    assert_eq!(v6.scope_id(), 20);
+}
+
+#[test]
+fn is_v4() {
+    let v4 = SocketAddr::V4(SocketAddrV4::new(Ipv4Addr::new(77, 88, 21, 11), 80));
+    assert!(v4.is_ipv4());
+    assert!(!v4.is_ipv6());
+}
+
+#[test]
+fn is_v6() {
+    let v6 = SocketAddr::V6(SocketAddrV6::new(
+        Ipv6Addr::new(0x2a02, 0x6b8, 0, 1, 0, 0, 0, 1),
+        80,
+        10,
+        0,
+    ));
+    assert!(!v6.is_ipv4());
+    assert!(v6.is_ipv6());
+}
+
+#[test]
+fn socket_v4_to_str() {
+    let socket = SocketAddrV4::new(Ipv4Addr::new(192, 168, 0, 1), 8080);
+
+    assert_eq!(format!("{socket}"), "192.168.0.1:8080");
+    assert_eq!(format!("{socket:<20}"), "192.168.0.1:8080    ");
+    assert_eq!(format!("{socket:>20}"), "    192.168.0.1:8080");
+    assert_eq!(format!("{socket:^20}"), "  192.168.0.1:8080  ");
+    assert_eq!(format!("{socket:.10}"), "192.168.0.");
+}
+
+#[test]
+fn socket_v6_to_str() {
+    let mut socket = SocketAddrV6::new(Ipv6Addr::new(0x2a02, 0x6b8, 0, 1, 0, 0, 0, 1), 53, 0, 0);
+
+    assert_eq!(format!("{socket}"), "[2a02:6b8:0:1::1]:53");
+    assert_eq!(format!("{socket:<24}"), "[2a02:6b8:0:1::1]:53    ");
+    assert_eq!(format!("{socket:>24}"), "    [2a02:6b8:0:1::1]:53");
+    assert_eq!(format!("{socket:^24}"), "  [2a02:6b8:0:1::1]:53  ");
+    assert_eq!(format!("{socket:.15}"), "[2a02:6b8:0:1::");
+
+    socket.set_scope_id(5);
+
+    assert_eq!(format!("{socket}"), "[2a02:6b8:0:1::1%5]:53");
+    assert_eq!(format!("{socket:<24}"), "[2a02:6b8:0:1::1%5]:53  ");
+    assert_eq!(format!("{socket:>24}"), "  [2a02:6b8:0:1::1%5]:53");
+    assert_eq!(format!("{socket:^24}"), " [2a02:6b8:0:1::1%5]:53 ");
+    assert_eq!(format!("{socket:.18}"), "[2a02:6b8:0:1::1%5");
+}
+
+#[test]
+fn compare() {
+    let v4_1 = "224.120.45.1:23456".parse::<SocketAddrV4>().unwrap();
+    let v4_2 = "224.210.103.5:12345".parse::<SocketAddrV4>().unwrap();
+    let v4_3 = "224.210.103.5:23456".parse::<SocketAddrV4>().unwrap();
+    let v6_1 = "[2001:db8:f00::1002]:23456".parse::<SocketAddrV6>().unwrap();
+    let v6_2 = "[2001:db8:f00::2001]:12345".parse::<SocketAddrV6>().unwrap();
+    let v6_3 = "[2001:db8:f00::2001]:23456".parse::<SocketAddrV6>().unwrap();
+
+    // equality
+    assert_eq!(v4_1, v4_1);
+    assert_eq!(v6_1, v6_1);
+    assert_eq!(SocketAddr::V4(v4_1), SocketAddr::V4(v4_1));
+    assert_eq!(SocketAddr::V6(v6_1), SocketAddr::V6(v6_1));
+    assert!(v4_1 != v4_2);
+    assert!(v6_1 != v6_2);
+
+    // compare different addresses
+    assert!(v4_1 < v4_2);
+    assert!(v6_1 < v6_2);
+    assert!(v4_2 > v4_1);
+    assert!(v6_2 > v6_1);
+
+    // compare the same address with different ports
+    assert!(v4_2 < v4_3);
+    assert!(v6_2 < v6_3);
+    assert!(v4_3 > v4_2);
+    assert!(v6_3 > v6_2);
+
+    // compare different addresses with the same port
+    assert!(v4_1 < v4_3);
+    assert!(v6_1 < v6_3);
+    assert!(v4_3 > v4_1);
+    assert!(v6_3 > v6_1);
+
+    // compare with an inferred right-hand side
+    assert_eq!(v4_1, "224.120.45.1:23456".parse().unwrap());
+    assert_eq!(v6_1, "[2001:db8:f00::1002]:23456".parse().unwrap());
+    assert_eq!(SocketAddr::V4(v4_1), "224.120.45.1:23456".parse().unwrap());
+}
diff --git a/library/std/src/net/ip.rs b/library/std/src/net/ip.rs
new file mode 100644
index 000000000..41ca9ba84
--- /dev/null
+++ b/library/std/src/net/ip.rs
@@ -0,0 +1,2040 @@
+// Tests for this module
+#[cfg(all(test, not(target_os = "emscripten")))]
+mod tests;
+
+use crate::cmp::Ordering;
+use crate::fmt::{self, Write as FmtWrite};
+use crate::io::Write as IoWrite;
+use crate::mem::transmute;
+use crate::sys::net::netc as c;
+use crate::sys_common::{FromInner, IntoInner};
+
+/// An IP address, either IPv4 or IPv6.
+///
+/// This enum can contain either an [`Ipv4Addr`] or an [`Ipv6Addr`], see their
+/// respective documentation for more details.
+///
+/// # Examples
+///
+/// ```
+/// use std::net::{IpAddr, Ipv4Addr, Ipv6Addr};
+///
+/// let localhost_v4 = IpAddr::V4(Ipv4Addr::new(127, 0, 0, 1));
+/// let localhost_v6 = IpAddr::V6(Ipv6Addr::new(0, 0, 0, 0, 0, 0, 0, 1));
+///
+/// assert_eq!("127.0.0.1".parse(), Ok(localhost_v4));
+/// assert_eq!("::1".parse(), Ok(localhost_v6));
+///
+/// assert_eq!(localhost_v4.is_ipv6(), false);
+/// assert_eq!(localhost_v4.is_ipv4(), true);
+/// ```
+#[stable(feature = "ip_addr", since = "1.7.0")]
+#[derive(Copy, Clone, Eq, PartialEq, Hash, PartialOrd, Ord)]
+pub enum IpAddr {
+    /// An IPv4 address.
+    #[stable(feature = "ip_addr", since = "1.7.0")]
+    V4(#[stable(feature = "ip_addr", since = "1.7.0")] Ipv4Addr),
+    /// An IPv6 address.
+    #[stable(feature = "ip_addr", since = "1.7.0")]
+    V6(#[stable(feature = "ip_addr", since = "1.7.0")] Ipv6Addr),
+}
+
+/// An IPv4 address.
+///
+/// IPv4 addresses are defined as 32-bit integers in [IETF RFC 791].
+/// They are usually represented as four octets.
+///
+/// See [`IpAddr`] for a type encompassing both IPv4 and IPv6 addresses.
+///
+/// [IETF RFC 791]: https://tools.ietf.org/html/rfc791
+///
+/// # Textual representation
+///
+/// `Ipv4Addr` provides a [`FromStr`] implementation. The four octets are in decimal
+/// notation, divided by `.` (this is called "dot-decimal notation").
+/// Notably, octal numbers (which are indicated with a leading `0`) and hexadecimal numbers (which
+/// are indicated with a leading `0x`) are not allowed per [IETF RFC 6943].
+///
+/// [IETF RFC 6943]: https://tools.ietf.org/html/rfc6943#section-3.1.1
+/// [`FromStr`]: crate::str::FromStr
+///
+/// # Examples
+///
+/// ```
+/// use std::net::Ipv4Addr;
+///
+/// let localhost = Ipv4Addr::new(127, 0, 0, 1);
+/// assert_eq!("127.0.0.1".parse(), Ok(localhost));
+/// assert_eq!(localhost.is_loopback(), true);
+/// assert!("012.004.002.000".parse::<Ipv4Addr>().is_err()); // all octets are in octal
+/// assert!("0000000.0.0.0".parse::<Ipv4Addr>().is_err()); // first octet is a zero in octal
+/// assert!("0xcb.0x0.0x71.0x00".parse::<Ipv4Addr>().is_err()); // all octets are in hex
+/// ```
+#[derive(Copy, Clone, PartialEq, Eq, Hash)]
+#[stable(feature = "rust1", since = "1.0.0")]
+pub struct Ipv4Addr {
+    octets: [u8; 4],
+}
+
+/// An IPv6 address.
+///
+/// IPv6 addresses are defined as 128-bit integers in [IETF RFC 4291].
+/// They are usually represented as eight 16-bit segments.
+///
+/// [IETF RFC 4291]: https://tools.ietf.org/html/rfc4291
+///
+/// # 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:
+///
+/// ```text
+/// |                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.
+///
+/// [IETF RFC 4291 Section 2.5.5.1]: https://datatracker.ietf.org/doc/html/rfc4291#section-2.5.5.1
+///
+/// ### 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:
+///
+/// ```text
+/// |                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.
+///
+/// [IETF RFC 4291 Section 2.5.5.2]: https://datatracker.ietf.org/doc/html/rfc4291#section-2.5.5.2
+///
+/// # 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].
+///
+/// [`FromStr`]: crate::str::FromStr
+/// [IETF RFC 5952]: https://tools.ietf.org/html/rfc5952
+///
+/// # 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);
+/// ```
+#[derive(Copy, Clone, PartialEq, Eq, Hash)]
+#[stable(feature = "rust1", since = "1.0.0")]
+pub struct Ipv6Addr {
+    octets: [u8; 16],
+}
+
+/// Scope of an [IPv6 multicast address] as defined in [IETF RFC 7346 section 2].
+///
+/// # Stability Guarantees
+///
+/// Not all possible values for a multicast scope have been assigned.
+/// Future RFCs may introduce new scopes, which will be added as variants to this enum;
+/// because of this the enum is marked as `#[non_exhaustive]`.
+///
+/// # Examples
+/// ```
+/// #![feature(ip)]
+///
+/// use std::net::Ipv6Addr;
+/// use std::net::Ipv6MulticastScope::*;
+///
+/// // An IPv6 multicast address with global scope (`ff0e::`).
+/// let address = Ipv6Addr::new(0xff0e, 0, 0, 0, 0, 0, 0, 0);
+///
+/// // Will print "Global scope".
+/// match address.multicast_scope() {
+///     Some(InterfaceLocal) => println!("Interface-Local scope"),
+///     Some(LinkLocal) => println!("Link-Local scope"),
+///     Some(RealmLocal) => println!("Realm-Local scope"),
+///     Some(AdminLocal) => println!("Admin-Local scope"),
+///     Some(SiteLocal) => println!("Site-Local scope"),
+///     Some(OrganizationLocal) => println!("Organization-Local scope"),
+///     Some(Global) => println!("Global scope"),
+///     Some(_) => println!("Unknown scope"),
+///     None => println!("Not a multicast address!")
+/// }
+///
+/// ```
+///
+/// [IPv6 multicast address]: Ipv6Addr
+/// [IETF RFC 7346 section 2]: https://tools.ietf.org/html/rfc7346#section-2
+#[derive(Copy, PartialEq, Eq, Clone, Hash, Debug)]
+#[unstable(feature = "ip", issue = "27709")]
+#[non_exhaustive]
+pub enum Ipv6MulticastScope {
+    /// Interface-Local scope.
+    InterfaceLocal,
+    /// Link-Local scope.
+    LinkLocal,
+    /// Realm-Local scope.
+    RealmLocal,
+    /// Admin-Local scope.
+    AdminLocal,
+    /// Site-Local scope.
+    SiteLocal,
+    /// Organization-Local scope.
+    OrganizationLocal,
+    /// Global scope.
+    Global,
+}
+
+impl IpAddr {
+    /// Returns [`true`] for the special 'unspecified' address.
+    ///
+    /// See the documentation for [`Ipv4Addr::is_unspecified()`] and
+    /// [`Ipv6Addr::is_unspecified()`] for more details.
+    ///
+    /// # Examples
+    ///
+    /// ```
+    /// use std::net::{IpAddr, Ipv4Addr, Ipv6Addr};
+    ///
+    /// assert_eq!(IpAddr::V4(Ipv4Addr::new(0, 0, 0, 0)).is_unspecified(), true);
+    /// assert_eq!(IpAddr::V6(Ipv6Addr::new(0, 0, 0, 0, 0, 0, 0, 0)).is_unspecified(), true);
+    /// ```
+    #[rustc_const_stable(feature = "const_ip_50", since = "1.50.0")]
+    #[stable(feature = "ip_shared", since = "1.12.0")]
+    #[must_use]
+    #[inline]
+    pub const fn is_unspecified(&self) -> bool {
+        match self {
+            IpAddr::V4(ip) => ip.is_unspecified(),
+            IpAddr::V6(ip) => ip.is_unspecified(),
+        }
+    }
+
+    /// Returns [`true`] if this is a loopback address.
+    ///
+    /// See the documentation for [`Ipv4Addr::is_loopback()`] and
+    /// [`Ipv6Addr::is_loopback()`] for more details.
+    ///
+    /// # Examples
+    ///
+    /// ```
+    /// use std::net::{IpAddr, Ipv4Addr, Ipv6Addr};
+    ///
+    /// assert_eq!(IpAddr::V4(Ipv4Addr::new(127, 0, 0, 1)).is_loopback(), true);
+    /// assert_eq!(IpAddr::V6(Ipv6Addr::new(0, 0, 0, 0, 0, 0, 0, 0x1)).is_loopback(), true);
+    /// ```
+    #[rustc_const_stable(feature = "const_ip_50", since = "1.50.0")]
+    #[stable(feature = "ip_shared", since = "1.12.0")]
+    #[must_use]
+    #[inline]
+    pub const fn is_loopback(&self) -> bool {
+        match self {
+            IpAddr::V4(ip) => ip.is_loopback(),
+            IpAddr::V6(ip) => ip.is_loopback(),
+        }
+    }
+
+    /// Returns [`true`] if the address appears to be globally routable.
+    ///
+    /// See the documentation for [`Ipv4Addr::is_global()`] and
+    /// [`Ipv6Addr::is_global()`] for more details.
+    ///
+    /// # Examples
+    ///
+    /// ```
+    /// #![feature(ip)]
+    ///
+    /// use std::net::{IpAddr, Ipv4Addr, Ipv6Addr};
+    ///
+    /// assert_eq!(IpAddr::V4(Ipv4Addr::new(80, 9, 12, 3)).is_global(), true);
+    /// assert_eq!(IpAddr::V6(Ipv6Addr::new(0, 0, 0x1c9, 0, 0, 0xafc8, 0, 0x1)).is_global(), true);
+    /// ```
+    #[rustc_const_unstable(feature = "const_ip", issue = "76205")]
+    #[unstable(feature = "ip", issue = "27709")]
+    #[must_use]
+    #[inline]
+    pub const fn is_global(&self) -> bool {
+        match self {
+            IpAddr::V4(ip) => ip.is_global(),
+            IpAddr::V6(ip) => ip.is_global(),
+        }
+    }
+
+    /// Returns [`true`] if this is a multicast address.
+    ///
+    /// See the documentation for [`Ipv4Addr::is_multicast()`] and
+    /// [`Ipv6Addr::is_multicast()`] for more details.
+    ///
+    /// # Examples
+    ///
+    /// ```
+    /// use std::net::{IpAddr, Ipv4Addr, Ipv6Addr};
+    ///
+    /// assert_eq!(IpAddr::V4(Ipv4Addr::new(224, 254, 0, 0)).is_multicast(), true);
+    /// assert_eq!(IpAddr::V6(Ipv6Addr::new(0xff00, 0, 0, 0, 0, 0, 0, 0)).is_multicast(), true);
+    /// ```
+    #[rustc_const_stable(feature = "const_ip_50", since = "1.50.0")]
+    #[stable(feature = "ip_shared", since = "1.12.0")]
+    #[must_use]
+    #[inline]
+    pub const fn is_multicast(&self) -> bool {
+        match self {
+            IpAddr::V4(ip) => ip.is_multicast(),
+            IpAddr::V6(ip) => ip.is_multicast(),
+        }
+    }
+
+    /// Returns [`true`] if this address is in a range designated for documentation.
+    ///
+    /// See the documentation for [`Ipv4Addr::is_documentation()`] and
+    /// [`Ipv6Addr::is_documentation()`] for more details.
+    ///
+    /// # Examples
+    ///
+    /// ```
+    /// #![feature(ip)]
+    ///
+    /// use std::net::{IpAddr, Ipv4Addr, Ipv6Addr};
+    ///
+    /// assert_eq!(IpAddr::V4(Ipv4Addr::new(203, 0, 113, 6)).is_documentation(), true);
+    /// assert_eq!(
+    ///     IpAddr::V6(Ipv6Addr::new(0x2001, 0xdb8, 0, 0, 0, 0, 0, 0)).is_documentation(),
+    ///     true
+    /// );
+    /// ```
+    #[rustc_const_unstable(feature = "const_ip", issue = "76205")]
+    #[unstable(feature = "ip", issue = "27709")]
+    #[must_use]
+    #[inline]
+    pub const fn is_documentation(&self) -> bool {
+        match self {
+            IpAddr::V4(ip) => ip.is_documentation(),
+            IpAddr::V6(ip) => ip.is_documentation(),
+        }
+    }
+
+    /// Returns [`true`] if this address is in a range designated for benchmarking.
+    ///
+    /// See the documentation for [`Ipv4Addr::is_benchmarking()`] and
+    /// [`Ipv6Addr::is_benchmarking()`] for more details.
+    ///
+    /// # Examples
+    ///
+    /// ```
+    /// #![feature(ip)]
+    ///
+    /// use std::net::{IpAddr, Ipv4Addr, Ipv6Addr};
+    ///
+    /// assert_eq!(IpAddr::V4(Ipv4Addr::new(198, 19, 255, 255)).is_benchmarking(), true);
+    /// assert_eq!(IpAddr::V6(Ipv6Addr::new(0x2001, 0x2, 0, 0, 0, 0, 0, 0)).is_benchmarking(), true);
+    /// ```
+    #[unstable(feature = "ip", issue = "27709")]
+    #[must_use]
+    #[inline]
+    pub const fn is_benchmarking(&self) -> bool {
+        match self {
+            IpAddr::V4(ip) => ip.is_benchmarking(),
+            IpAddr::V6(ip) => ip.is_benchmarking(),
+        }
+    }
+
+    /// Returns [`true`] if this address is an [`IPv4` address], and [`false`]
+    /// otherwise.
+    ///
+    /// [`IPv4` address]: IpAddr::V4
+    ///
+    /// # Examples
+    ///
+    /// ```
+    /// use std::net::{IpAddr, Ipv4Addr, Ipv6Addr};
+    ///
+    /// assert_eq!(IpAddr::V4(Ipv4Addr::new(203, 0, 113, 6)).is_ipv4(), true);
+    /// assert_eq!(IpAddr::V6(Ipv6Addr::new(0x2001, 0xdb8, 0, 0, 0, 0, 0, 0)).is_ipv4(), false);
+    /// ```
+    #[rustc_const_stable(feature = "const_ip_50", since = "1.50.0")]
+    #[stable(feature = "ipaddr_checker", since = "1.16.0")]
+    #[must_use]
+    #[inline]
+    pub const fn is_ipv4(&self) -> bool {
+        matches!(self, IpAddr::V4(_))
+    }
+
+    /// Returns [`true`] if this address is an [`IPv6` address], and [`false`]
+    /// otherwise.
+    ///
+    /// [`IPv6` address]: IpAddr::V6
+    ///
+    /// # Examples
+    ///
+    /// ```
+    /// use std::net::{IpAddr, Ipv4Addr, Ipv6Addr};
+    ///
+    /// assert_eq!(IpAddr::V4(Ipv4Addr::new(203, 0, 113, 6)).is_ipv6(), false);
+    /// assert_eq!(IpAddr::V6(Ipv6Addr::new(0x2001, 0xdb8, 0, 0, 0, 0, 0, 0)).is_ipv6(), true);
+    /// ```
+    #[rustc_const_stable(feature = "const_ip_50", since = "1.50.0")]
+    #[stable(feature = "ipaddr_checker", since = "1.16.0")]
+    #[must_use]
+    #[inline]
+    pub const fn is_ipv6(&self) -> bool {
+        matches!(self, IpAddr::V6(_))
+    }
+
+    /// Converts this address to an `IpAddr::V4` if it is an IPv4-mapped IPv6 addresses, otherwise it
+    /// return `self` as-is.
+    ///
+    /// # Examples
+    ///
+    /// ```
+    /// #![feature(ip)]
+    /// use std::net::{IpAddr, Ipv4Addr, Ipv6Addr};
+    ///
+    /// assert_eq!(IpAddr::V4(Ipv4Addr::new(127, 0, 0, 1)).to_canonical().is_loopback(), true);
+    /// assert_eq!(IpAddr::V6(Ipv6Addr::new(0, 0, 0, 0, 0, 0xffff, 0x7f00, 0x1)).is_loopback(), false);
+    /// assert_eq!(IpAddr::V6(Ipv6Addr::new(0, 0, 0, 0, 0, 0xffff, 0x7f00, 0x1)).to_canonical().is_loopback(), true);
+    /// ```
+    #[inline]
+    #[must_use = "this returns the result of the operation, \
+                  without modifying the original"]
+    #[rustc_const_unstable(feature = "const_ip", issue = "76205")]
+    #[unstable(feature = "ip", issue = "27709")]
+    pub const fn to_canonical(&self) -> IpAddr {
+        match self {
+            &v4 @ IpAddr::V4(_) => v4,
+            IpAddr::V6(v6) => v6.to_canonical(),
+        }
+    }
+}
+
+impl Ipv4Addr {
+    /// Creates a new IPv4 address from four eight-bit octets.
+    ///
+    /// The result will represent the IP address `a`.`b`.`c`.`d`.
+    ///
+    /// # Examples
+    ///
+    /// ```
+    /// use std::net::Ipv4Addr;
+    ///
+    /// let addr = Ipv4Addr::new(127, 0, 0, 1);
+    /// ```
+    #[rustc_const_stable(feature = "const_ip_32", since = "1.32.0")]
+    #[stable(feature = "rust1", since = "1.0.0")]
+    #[must_use]
+    #[inline]
+    pub const fn new(a: u8, b: u8, c: u8, d: u8) -> Ipv4Addr {
+        Ipv4Addr { octets: [a, b, c, d] }
+    }
+
+    /// An IPv4 address with the address pointing to localhost: `127.0.0.1`
+    ///
+    /// # Examples
+    ///
+    /// ```
+    /// use std::net::Ipv4Addr;
+    ///
+    /// let addr = Ipv4Addr::LOCALHOST;
+    /// assert_eq!(addr, Ipv4Addr::new(127, 0, 0, 1));
+    /// ```
+    #[stable(feature = "ip_constructors", since = "1.30.0")]
+    pub const LOCALHOST: Self = Ipv4Addr::new(127, 0, 0, 1);
+
+    /// An IPv4 address representing an unspecified address: `0.0.0.0`
+    ///
+    /// This corresponds to the constant `INADDR_ANY` in other languages.
+    ///
+    /// # Examples
+    ///
+    /// ```
+    /// use std::net::Ipv4Addr;
+    ///
+    /// let addr = Ipv4Addr::UNSPECIFIED;
+    /// assert_eq!(addr, Ipv4Addr::new(0, 0, 0, 0));
+    /// ```
+    #[doc(alias = "INADDR_ANY")]
+    #[stable(feature = "ip_constructors", since = "1.30.0")]
+    pub const UNSPECIFIED: Self = Ipv4Addr::new(0, 0, 0, 0);
+
+    /// An IPv4 address representing the broadcast address: `255.255.255.255`
+    ///
+    /// # Examples
+    ///
+    /// ```
+    /// use std::net::Ipv4Addr;
+    ///
+    /// let addr = Ipv4Addr::BROADCAST;
+    /// assert_eq!(addr, Ipv4Addr::new(255, 255, 255, 255));
+    /// ```
+    #[stable(feature = "ip_constructors", since = "1.30.0")]
+    pub const BROADCAST: Self = Ipv4Addr::new(255, 255, 255, 255);
+
+    /// Returns the four eight-bit integers that make up this address.
+    ///
+    /// # Examples
+    ///
+    /// ```
+    /// use std::net::Ipv4Addr;
+    ///
+    /// let addr = Ipv4Addr::new(127, 0, 0, 1);
+    /// assert_eq!(addr.octets(), [127, 0, 0, 1]);
+    /// ```
+    #[rustc_const_stable(feature = "const_ip_50", since = "1.50.0")]
+    #[stable(feature = "rust1", since = "1.0.0")]
+    #[must_use]
+    #[inline]
+    pub const fn octets(&self) -> [u8; 4] {
+        self.octets
+    }
+
+    /// Returns [`true`] for the special 'unspecified' address (`0.0.0.0`).
+    ///
+    /// This property is defined in _UNIX Network Programming, Second Edition_,
+    /// W. Richard Stevens, p. 891; see also [ip7].
+    ///
+    /// [ip7]: https://man7.org/linux/man-pages/man7/ip.7.html
+    ///
+    /// # Examples
+    ///
+    /// ```
+    /// use std::net::Ipv4Addr;
+    ///
+    /// assert_eq!(Ipv4Addr::new(0, 0, 0, 0).is_unspecified(), true);
+    /// assert_eq!(Ipv4Addr::new(45, 22, 13, 197).is_unspecified(), false);
+    /// ```
+    #[rustc_const_stable(feature = "const_ip_32", since = "1.32.0")]
+    #[stable(feature = "ip_shared", since = "1.12.0")]
+    #[must_use]
+    #[inline]
+    pub const fn is_unspecified(&self) -> bool {
+        u32::from_be_bytes(self.octets) == 0
+    }
+
+    /// Returns [`true`] if this is a loopback address (`127.0.0.0/8`).
+    ///
+    /// This property is defined by [IETF RFC 1122].
+    ///
+    /// [IETF RFC 1122]: https://tools.ietf.org/html/rfc1122
+    ///
+    /// # Examples
+    ///
+    /// ```
+    /// use std::net::Ipv4Addr;
+    ///
+    /// assert_eq!(Ipv4Addr::new(127, 0, 0, 1).is_loopback(), true);
+    /// assert_eq!(Ipv4Addr::new(45, 22, 13, 197).is_loopback(), false);
+    /// ```
+    #[rustc_const_stable(feature = "const_ip_50", since = "1.50.0")]
+    #[stable(since = "1.7.0", feature = "ip_17")]
+    #[must_use]
+    #[inline]
+    pub const fn is_loopback(&self) -> bool {
+        self.octets()[0] == 127
+    }
+
+    /// Returns [`true`] if this is a private address.
+    ///
+    /// The private address ranges are defined in [IETF RFC 1918] and include:
+    ///
+    ///  - `10.0.0.0/8`
+    ///  - `172.16.0.0/12`
+    ///  - `192.168.0.0/16`
+    ///
+    /// [IETF RFC 1918]: https://tools.ietf.org/html/rfc1918
+    ///
+    /// # Examples
+    ///
+    /// ```
+    /// use std::net::Ipv4Addr;
+    ///
+    /// assert_eq!(Ipv4Addr::new(10, 0, 0, 1).is_private(), true);
+    /// assert_eq!(Ipv4Addr::new(10, 10, 10, 10).is_private(), true);
+    /// assert_eq!(Ipv4Addr::new(172, 16, 10, 10).is_private(), true);
+    /// assert_eq!(Ipv4Addr::new(172, 29, 45, 14).is_private(), true);
+    /// assert_eq!(Ipv4Addr::new(172, 32, 0, 2).is_private(), false);
+    /// assert_eq!(Ipv4Addr::new(192, 168, 0, 2).is_private(), true);
+    /// assert_eq!(Ipv4Addr::new(192, 169, 0, 2).is_private(), false);
+    /// ```
+    #[rustc_const_stable(feature = "const_ip_50", since = "1.50.0")]
+    #[stable(since = "1.7.0", feature = "ip_17")]
+    #[must_use]
+    #[inline]
+    pub const fn is_private(&self) -> bool {
+        match self.octets() {
+            [10, ..] => true,
+            [172, b, ..] if b >= 16 && b <= 31 => true,
+            [192, 168, ..] => true,
+            _ => false,
+        }
+    }
+
+    /// Returns [`true`] if the address is link-local (`169.254.0.0/16`).
+    ///
+    /// This property is defined by [IETF RFC 3927].
+    ///
+    /// [IETF RFC 3927]: https://tools.ietf.org/html/rfc3927
+    ///
+    /// # Examples
+    ///
+    /// ```
+    /// use std::net::Ipv4Addr;
+    ///
+    /// assert_eq!(Ipv4Addr::new(169, 254, 0, 0).is_link_local(), true);
+    /// assert_eq!(Ipv4Addr::new(169, 254, 10, 65).is_link_local(), true);
+    /// assert_eq!(Ipv4Addr::new(16, 89, 10, 65).is_link_local(), false);
+    /// ```
+    #[rustc_const_stable(feature = "const_ip_50", since = "1.50.0")]
+    #[stable(since = "1.7.0", feature = "ip_17")]
+    #[must_use]
+    #[inline]
+    pub const fn is_link_local(&self) -> bool {
+        matches!(self.octets(), [169, 254, ..])
+    }
+
+    /// Returns [`true`] if the address appears to be globally routable.
+    /// See [iana-ipv4-special-registry][ipv4-sr].
+    ///
+    /// The following return [`false`]:
+    ///
+    /// - private addresses (see [`Ipv4Addr::is_private()`])
+    /// - the loopback address (see [`Ipv4Addr::is_loopback()`])
+    /// - the link-local address (see [`Ipv4Addr::is_link_local()`])
+    /// - the broadcast address (see [`Ipv4Addr::is_broadcast()`])
+    /// - addresses used for documentation (see [`Ipv4Addr::is_documentation()`])
+    /// - the unspecified address (see [`Ipv4Addr::is_unspecified()`]), and the whole
+    ///   `0.0.0.0/8` block
+    /// - addresses reserved for future protocols, except
+    /// `192.0.0.9/32` and `192.0.0.10/32` which are globally routable
+    /// - addresses reserved for future use (see [`Ipv4Addr::is_reserved()`]
+    /// - addresses reserved for networking devices benchmarking (see
+    /// [`Ipv4Addr::is_benchmarking()`])
+    ///
+    /// [ipv4-sr]: https://www.iana.org/assignments/iana-ipv4-special-registry/iana-ipv4-special-registry.xhtml
+    ///
+    /// # Examples
+    ///
+    /// ```
+    /// #![feature(ip)]
+    ///
+    /// use std::net::Ipv4Addr;
+    ///
+    /// // private addresses are not global
+    /// assert_eq!(Ipv4Addr::new(10, 254, 0, 0).is_global(), false);
+    /// assert_eq!(Ipv4Addr::new(192, 168, 10, 65).is_global(), false);
+    /// assert_eq!(Ipv4Addr::new(172, 16, 10, 65).is_global(), false);
+    ///
+    /// // the 0.0.0.0/8 block is not global
+    /// assert_eq!(Ipv4Addr::new(0, 1, 2, 3).is_global(), false);
+    /// // in particular, the unspecified address is not global
+    /// assert_eq!(Ipv4Addr::new(0, 0, 0, 0).is_global(), false);
+    ///
+    /// // the loopback address is not global
+    /// assert_eq!(Ipv4Addr::new(127, 0, 0, 1).is_global(), false);
+    ///
+    /// // link local addresses are not global
+    /// assert_eq!(Ipv4Addr::new(169, 254, 45, 1).is_global(), false);
+    ///
+    /// // the broadcast address is not global
+    /// assert_eq!(Ipv4Addr::new(255, 255, 255, 255).is_global(), false);
+    ///
+    /// // the address space designated for documentation is not global
+    /// assert_eq!(Ipv4Addr::new(192, 0, 2, 255).is_global(), false);
+    /// assert_eq!(Ipv4Addr::new(198, 51, 100, 65).is_global(), false);
+    /// assert_eq!(Ipv4Addr::new(203, 0, 113, 6).is_global(), false);
+    ///
+    /// // shared addresses are not global
+    /// assert_eq!(Ipv4Addr::new(100, 100, 0, 0).is_global(), false);
+    ///
+    /// // addresses reserved for protocol assignment are not global
+    /// assert_eq!(Ipv4Addr::new(192, 0, 0, 0).is_global(), false);
+    /// assert_eq!(Ipv4Addr::new(192, 0, 0, 255).is_global(), false);
+    ///
+    /// // addresses reserved for future use are not global
+    /// assert_eq!(Ipv4Addr::new(250, 10, 20, 30).is_global(), false);
+    ///
+    /// // addresses reserved for network devices benchmarking are not global
+    /// assert_eq!(Ipv4Addr::new(198, 18, 0, 0).is_global(), false);
+    ///
+    /// // All the other addresses are global
+    /// assert_eq!(Ipv4Addr::new(1, 1, 1, 1).is_global(), true);
+    /// assert_eq!(Ipv4Addr::new(80, 9, 12, 3).is_global(), true);
+    /// ```
+    #[rustc_const_unstable(feature = "const_ipv4", issue = "76205")]
+    #[unstable(feature = "ip", issue = "27709")]
+    #[must_use]
+    #[inline]
+    pub const fn is_global(&self) -> bool {
+        // check if this address is 192.0.0.9 or 192.0.0.10. These addresses are the only two
+        // globally routable addresses in the 192.0.0.0/24 range.
+        if u32::from_be_bytes(self.octets()) == 0xc0000009
+            || u32::from_be_bytes(self.octets()) == 0xc000000a
+        {
+            return true;
+        }
+        !self.is_private()
+            && !self.is_loopback()
+            && !self.is_link_local()
+            && !self.is_broadcast()
+            && !self.is_documentation()
+            && !self.is_shared()
+            // addresses reserved for future protocols (`192.0.0.0/24`)
+            && !(self.octets()[0] == 192 && self.octets()[1] == 0 && self.octets()[2] == 0)
+            && !self.is_reserved()
+            && !self.is_benchmarking()
+            // Make sure the address is not in 0.0.0.0/8
+            && self.octets()[0] != 0
+    }
+
+    /// Returns [`true`] if this address is part of the Shared Address Space defined in
+    /// [IETF RFC 6598] (`100.64.0.0/10`).
+    ///
+    /// [IETF RFC 6598]: https://tools.ietf.org/html/rfc6598
+    ///
+    /// # Examples
+    ///
+    /// ```
+    /// #![feature(ip)]
+    /// use std::net::Ipv4Addr;
+    ///
+    /// assert_eq!(Ipv4Addr::new(100, 64, 0, 0).is_shared(), true);
+    /// assert_eq!(Ipv4Addr::new(100, 127, 255, 255).is_shared(), true);
+    /// assert_eq!(Ipv4Addr::new(100, 128, 0, 0).is_shared(), false);
+    /// ```
+    #[rustc_const_unstable(feature = "const_ipv4", issue = "76205")]
+    #[unstable(feature = "ip", issue = "27709")]
+    #[must_use]
+    #[inline]
+    pub const fn is_shared(&self) -> bool {
+        self.octets()[0] == 100 && (self.octets()[1] & 0b1100_0000 == 0b0100_0000)
+    }
+
+    /// Returns [`true`] if this address part of the `198.18.0.0/15` range, which is reserved for
+    /// network devices benchmarking. This range is defined in [IETF RFC 2544] as `192.18.0.0`
+    /// through `198.19.255.255` but [errata 423] corrects it to `198.18.0.0/15`.
+    ///
+    /// [IETF RFC 2544]: https://tools.ietf.org/html/rfc2544
+    /// [errata 423]: https://www.rfc-editor.org/errata/eid423
+    ///
+    /// # Examples
+    ///
+    /// ```
+    /// #![feature(ip)]
+    /// use std::net::Ipv4Addr;
+    ///
+    /// assert_eq!(Ipv4Addr::new(198, 17, 255, 255).is_benchmarking(), false);
+    /// assert_eq!(Ipv4Addr::new(198, 18, 0, 0).is_benchmarking(), true);
+    /// assert_eq!(Ipv4Addr::new(198, 19, 255, 255).is_benchmarking(), true);
+    /// assert_eq!(Ipv4Addr::new(198, 20, 0, 0).is_benchmarking(), false);
+    /// ```
+    #[rustc_const_unstable(feature = "const_ipv4", issue = "76205")]
+    #[unstable(feature = "ip", issue = "27709")]
+    #[must_use]
+    #[inline]
+    pub const fn is_benchmarking(&self) -> bool {
+        self.octets()[0] == 198 && (self.octets()[1] & 0xfe) == 18
+    }
+
+    /// Returns [`true`] if this address is reserved by IANA for future use. [IETF RFC 1112]
+    /// defines the block of reserved addresses as `240.0.0.0/4`. This range normally includes the
+    /// broadcast address `255.255.255.255`, but this implementation explicitly excludes it, since
+    /// it is obviously not reserved for future use.
+    ///
+    /// [IETF RFC 1112]: https://tools.ietf.org/html/rfc1112
+    ///
+    /// # Warning
+    ///
+    /// As IANA assigns new addresses, this method will be
+    /// updated. This may result in non-reserved addresses being
+    /// treated as reserved in code that relies on an outdated version
+    /// of this method.
+    ///
+    /// # Examples
+    ///
+    /// ```
+    /// #![feature(ip)]
+    /// use std::net::Ipv4Addr;
+    ///
+    /// assert_eq!(Ipv4Addr::new(240, 0, 0, 0).is_reserved(), true);
+    /// assert_eq!(Ipv4Addr::new(255, 255, 255, 254).is_reserved(), true);
+    ///
+    /// assert_eq!(Ipv4Addr::new(239, 255, 255, 255).is_reserved(), false);
+    /// // The broadcast address is not considered as reserved for future use by this implementation
+    /// assert_eq!(Ipv4Addr::new(255, 255, 255, 255).is_reserved(), false);
+    /// ```
+    #[rustc_const_unstable(feature = "const_ipv4", issue = "76205")]
+    #[unstable(feature = "ip", issue = "27709")]
+    #[must_use]
+    #[inline]
+    pub const fn is_reserved(&self) -> bool {
+        self.octets()[0] & 240 == 240 && !self.is_broadcast()
+    }
+
+    /// Returns [`true`] if this is a multicast address (`224.0.0.0/4`).
+    ///
+    /// Multicast addresses have a most significant octet between `224` and `239`,
+    /// and is defined by [IETF RFC 5771].
+    ///
+    /// [IETF RFC 5771]: https://tools.ietf.org/html/rfc5771
+    ///
+    /// # Examples
+    ///
+    /// ```
+    /// use std::net::Ipv4Addr;
+    ///
+    /// assert_eq!(Ipv4Addr::new(224, 254, 0, 0).is_multicast(), true);
+    /// assert_eq!(Ipv4Addr::new(236, 168, 10, 65).is_multicast(), true);
+    /// assert_eq!(Ipv4Addr::new(172, 16, 10, 65).is_multicast(), false);
+    /// ```
+    #[rustc_const_stable(feature = "const_ip_50", since = "1.50.0")]
+    #[stable(since = "1.7.0", feature = "ip_17")]
+    #[must_use]
+    #[inline]
+    pub const fn is_multicast(&self) -> bool {
+        self.octets()[0] >= 224 && self.octets()[0] <= 239
+    }
+
+    /// Returns [`true`] if this is a broadcast address (`255.255.255.255`).
+    ///
+    /// A broadcast address has all octets set to `255` as defined in [IETF RFC 919].
+    ///
+    /// [IETF RFC 919]: https://tools.ietf.org/html/rfc919
+    ///
+    /// # Examples
+    ///
+    /// ```
+    /// use std::net::Ipv4Addr;
+    ///
+    /// assert_eq!(Ipv4Addr::new(255, 255, 255, 255).is_broadcast(), true);
+    /// assert_eq!(Ipv4Addr::new(236, 168, 10, 65).is_broadcast(), false);
+    /// ```
+    #[rustc_const_stable(feature = "const_ip_50", since = "1.50.0")]
+    #[stable(since = "1.7.0", feature = "ip_17")]
+    #[must_use]
+    #[inline]
+    pub const fn is_broadcast(&self) -> bool {
+        u32::from_be_bytes(self.octets()) == u32::from_be_bytes(Self::BROADCAST.octets())
+    }
+
+    /// Returns [`true`] if this address is in a range designated for documentation.
+    ///
+    /// This is defined in [IETF RFC 5737]:
+    ///
+    /// - `192.0.2.0/24` (TEST-NET-1)
+    /// - `198.51.100.0/24` (TEST-NET-2)
+    /// - `203.0.113.0/24` (TEST-NET-3)
+    ///
+    /// [IETF RFC 5737]: https://tools.ietf.org/html/rfc5737
+    ///
+    /// # Examples
+    ///
+    /// ```
+    /// use std::net::Ipv4Addr;
+    ///
+    /// assert_eq!(Ipv4Addr::new(192, 0, 2, 255).is_documentation(), true);
+    /// assert_eq!(Ipv4Addr::new(198, 51, 100, 65).is_documentation(), true);
+    /// assert_eq!(Ipv4Addr::new(203, 0, 113, 6).is_documentation(), true);
+    /// assert_eq!(Ipv4Addr::new(193, 34, 17, 19).is_documentation(), false);
+    /// ```
+    #[rustc_const_stable(feature = "const_ip_50", since = "1.50.0")]
+    #[stable(since = "1.7.0", feature = "ip_17")]
+    #[must_use]
+    #[inline]
+    pub const fn is_documentation(&self) -> bool {
+        matches!(self.octets(), [192, 0, 2, _] | [198, 51, 100, _] | [203, 0, 113, _])
+    }
+
+    /// Converts this address to an [IPv4-compatible] [`IPv6` address].
+    ///
+    /// `a.b.c.d` becomes `::a.b.c.d`
+    ///
+    /// Note that IPv4-compatible addresses have been officially deprecated.
+    /// If you don't explicitly need an IPv4-compatible address for legacy reasons, consider using `to_ipv6_mapped` instead.
+    ///
+    /// [IPv4-compatible]: Ipv6Addr#ipv4-compatible-ipv6-addresses
+    /// [`IPv6` address]: Ipv6Addr
+    ///
+    /// # Examples
+    ///
+    /// ```
+    /// use std::net::{Ipv4Addr, Ipv6Addr};
+    ///
+    /// assert_eq!(
+    ///     Ipv4Addr::new(192, 0, 2, 255).to_ipv6_compatible(),
+    ///     Ipv6Addr::new(0, 0, 0, 0, 0, 0, 0xc000, 0x2ff)
+    /// );
+    /// ```
+    #[rustc_const_stable(feature = "const_ip_50", since = "1.50.0")]
+    #[stable(feature = "rust1", since = "1.0.0")]
+    #[must_use = "this returns the result of the operation, \
+                  without modifying the original"]
+    #[inline]
+    pub const fn to_ipv6_compatible(&self) -> Ipv6Addr {
+        let [a, b, c, d] = self.octets();
+        Ipv6Addr { octets: [0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, a, b, c, d] }
+    }
+
+    /// Converts this address to an [IPv4-mapped] [`IPv6` address].
+    ///
+    /// `a.b.c.d` becomes `::ffff:a.b.c.d`
+    ///
+    /// [IPv4-mapped]: Ipv6Addr#ipv4-mapped-ipv6-addresses
+    /// [`IPv6` address]: Ipv6Addr
+    ///
+    /// # Examples
+    ///
+    /// ```
+    /// use std::net::{Ipv4Addr, Ipv6Addr};
+    ///
+    /// assert_eq!(Ipv4Addr::new(192, 0, 2, 255).to_ipv6_mapped(),
+    ///            Ipv6Addr::new(0, 0, 0, 0, 0, 0xffff, 0xc000, 0x2ff));
+    /// ```
+    #[rustc_const_stable(feature = "const_ip_50", since = "1.50.0")]
+    #[stable(feature = "rust1", since = "1.0.0")]
+    #[must_use = "this returns the result of the operation, \
+                  without modifying the original"]
+    #[inline]
+    pub const fn to_ipv6_mapped(&self) -> Ipv6Addr {
+        let [a, b, c, d] = self.octets();
+        Ipv6Addr { octets: [0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0xFF, 0xFF, a, b, c, d] }
+    }
+}
+
+#[stable(feature = "ip_addr", since = "1.7.0")]
+impl fmt::Display for IpAddr {
+    fn fmt(&self, fmt: &mut fmt::Formatter<'_>) -> fmt::Result {
+        match self {
+            IpAddr::V4(ip) => ip.fmt(fmt),
+            IpAddr::V6(ip) => ip.fmt(fmt),
+        }
+    }
+}
+
+#[stable(feature = "ip_addr", since = "1.7.0")]
+impl fmt::Debug for IpAddr {
+    fn fmt(&self, fmt: &mut fmt::Formatter<'_>) -> fmt::Result {
+        fmt::Display::fmt(self, fmt)
+    }
+}
+
+#[stable(feature = "ip_from_ip", since = "1.16.0")]
+impl From<Ipv4Addr> for IpAddr {
+    /// Copies this address to a new `IpAddr::V4`.
+    ///
+    /// # Examples
+    ///
+    /// ```
+    /// use std::net::{IpAddr, Ipv4Addr};
+    ///
+    /// let addr = Ipv4Addr::new(127, 0, 0, 1);
+    ///
+    /// assert_eq!(
+    ///     IpAddr::V4(addr),
+    ///     IpAddr::from(addr)
+    /// )
+    /// ```
+    #[inline]
+    fn from(ipv4: Ipv4Addr) -> IpAddr {
+        IpAddr::V4(ipv4)
+    }
+}
+
+#[stable(feature = "ip_from_ip", since = "1.16.0")]
+impl From<Ipv6Addr> for 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)
+    /// );
+    /// ```
+    #[inline]
+    fn from(ipv6: Ipv6Addr) -> IpAddr {
+        IpAddr::V6(ipv6)
+    }
+}
+
+#[stable(feature = "rust1", since = "1.0.0")]
+impl fmt::Display for Ipv4Addr {
+    fn fmt(&self, fmt: &mut fmt::Formatter<'_>) -> fmt::Result {
+        let octets = self.octets();
+        // Fast Path: if there's no alignment stuff, write directly to the buffer
+        if fmt.precision().is_none() && fmt.width().is_none() {
+            write!(fmt, "{}.{}.{}.{}", octets[0], octets[1], octets[2], octets[3])
+        } else {
+            const IPV4_BUF_LEN: usize = 15; // Long enough for the longest possible IPv4 address
+            let mut buf = [0u8; IPV4_BUF_LEN];
+            let mut buf_slice = &mut buf[..];
+
+            // Note: The call to write should never fail, hence the unwrap
+            write!(buf_slice, "{}.{}.{}.{}", octets[0], octets[1], octets[2], octets[3]).unwrap();
+            let len = IPV4_BUF_LEN - buf_slice.len();
+
+            // This unsafe is OK because we know what is being written to the buffer
+            let buf = unsafe { crate::str::from_utf8_unchecked(&buf[..len]) };
+            fmt.pad(buf)
+        }
+    }
+}
+
+#[stable(feature = "rust1", since = "1.0.0")]
+impl fmt::Debug for Ipv4Addr {
+    fn fmt(&self, fmt: &mut fmt::Formatter<'_>) -> fmt::Result {
+        fmt::Display::fmt(self, fmt)
+    }
+}
+
+#[stable(feature = "ip_cmp", since = "1.16.0")]
+impl PartialEq<Ipv4Addr> for IpAddr {
+    #[inline]
+    fn eq(&self, other: &Ipv4Addr) -> bool {
+        match self {
+            IpAddr::V4(v4) => v4 == other,
+            IpAddr::V6(_) => false,
+        }
+    }
+}
+
+#[stable(feature = "ip_cmp", since = "1.16.0")]
+impl PartialEq<IpAddr> for Ipv4Addr {
+    #[inline]
+    fn eq(&self, other: &IpAddr) -> bool {
+        match other {
+            IpAddr::V4(v4) => self == v4,
+            IpAddr::V6(_) => false,
+        }
+    }
+}
+
+#[stable(feature = "rust1", since = "1.0.0")]
+impl PartialOrd for Ipv4Addr {
+    #[inline]
+    fn partial_cmp(&self, other: &Ipv4Addr) -> Option<Ordering> {
+        Some(self.cmp(other))
+    }
+}
+
+#[stable(feature = "ip_cmp", since = "1.16.0")]
+impl PartialOrd<Ipv4Addr> for IpAddr {
+    #[inline]
+    fn partial_cmp(&self, other: &Ipv4Addr) -> Option<Ordering> {
+        match self {
+            IpAddr::V4(v4) => v4.partial_cmp(other),
+            IpAddr::V6(_) => Some(Ordering::Greater),
+        }
+    }
+}
+
+#[stable(feature = "ip_cmp", since = "1.16.0")]
+impl PartialOrd<IpAddr> for Ipv4Addr {
+    #[inline]
+    fn partial_cmp(&self, other: &IpAddr) -> Option<Ordering> {
+        match other {
+            IpAddr::V4(v4) => self.partial_cmp(v4),
+            IpAddr::V6(_) => Some(Ordering::Less),
+        }
+    }
+}
+
+#[stable(feature = "rust1", since = "1.0.0")]
+impl Ord for Ipv4Addr {
+    #[inline]
+    fn cmp(&self, other: &Ipv4Addr) -> Ordering {
+        self.octets.cmp(&other.octets)
+    }
+}
+
+impl IntoInner<c::in_addr> for Ipv4Addr {
+    #[inline]
+    fn into_inner(self) -> c::in_addr {
+        // `s_addr` is stored as BE on all machines and the array is in BE order.
+        // So the native endian conversion method is used so that it's never swapped.
+        c::in_addr { s_addr: u32::from_ne_bytes(self.octets) }
+    }
+}
+impl FromInner<c::in_addr> for Ipv4Addr {
+    fn from_inner(addr: c::in_addr) -> Ipv4Addr {
+        Ipv4Addr { octets: addr.s_addr.to_ne_bytes() }
+    }
+}
+
+#[stable(feature = "ip_u32", since = "1.1.0")]
+impl From<Ipv4Addr> for u32 {
+    /// Converts an `Ipv4Addr` into a host byte order `u32`.
+    ///
+    /// # Examples
+    ///
+    /// ```
+    /// use std::net::Ipv4Addr;
+    ///
+    /// let addr = Ipv4Addr::new(0x12, 0x34, 0x56, 0x78);
+    /// assert_eq!(0x12345678, u32::from(addr));
+    /// ```
+    #[inline]
+    fn from(ip: Ipv4Addr) -> u32 {
+        u32::from_be_bytes(ip.octets)
+    }
+}
+
+#[stable(feature = "ip_u32", since = "1.1.0")]
+impl From<u32> for Ipv4Addr {
+    /// Converts a host byte order `u32` into an `Ipv4Addr`.
+    ///
+    /// # Examples
+    ///
+    /// ```
+    /// use std::net::Ipv4Addr;
+    ///
+    /// let addr = Ipv4Addr::from(0x12345678);
+    /// assert_eq!(Ipv4Addr::new(0x12, 0x34, 0x56, 0x78), addr);
+    /// ```
+    #[inline]
+    fn from(ip: u32) -> Ipv4Addr {
+        Ipv4Addr { octets: ip.to_be_bytes() }
+    }
+}
+
+#[stable(feature = "from_slice_v4", since = "1.9.0")]
+impl From<[u8; 4]> for Ipv4Addr {
+    /// Creates an `Ipv4Addr` from a four element byte array.
+    ///
+    /// # Examples
+    ///
+    /// ```
+    /// use std::net::Ipv4Addr;
+    ///
+    /// let addr = Ipv4Addr::from([13u8, 12u8, 11u8, 10u8]);
+    /// assert_eq!(Ipv4Addr::new(13, 12, 11, 10), addr);
+    /// ```
+    #[inline]
+    fn from(octets: [u8; 4]) -> Ipv4Addr {
+        Ipv4Addr { octets }
+    }
+}
+
+#[stable(feature = "ip_from_slice", since = "1.17.0")]
+impl From<[u8; 4]> for IpAddr {
+    /// Creates an `IpAddr::V4` from a four element byte array.
+    ///
+    /// # Examples
+    ///
+    /// ```
+    /// use std::net::{IpAddr, Ipv4Addr};
+    ///
+    /// let addr = IpAddr::from([13u8, 12u8, 11u8, 10u8]);
+    /// assert_eq!(IpAddr::V4(Ipv4Addr::new(13, 12, 11, 10)), addr);
+    /// ```
+    #[inline]
+    fn from(octets: [u8; 4]) -> IpAddr {
+        IpAddr::V4(Ipv4Addr::from(octets))
+    }
+}
+
+impl 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);
+    /// ```
+    #[rustc_const_stable(feature = "const_ip_32", since = "1.32.0")]
+    #[stable(feature = "rust1", since = "1.0.0")]
+    #[must_use]
+    #[inline]
+    pub const fn new(a: u16, b: u16, c: u16, d: u16, e: u16, f: u16, g: u16, h: u16) -> Ipv6Addr {
+        let addr16 = [
+            a.to_be(),
+            b.to_be(),
+            c.to_be(),
+            d.to_be(),
+            e.to_be(),
+            f.to_be(),
+            g.to_be(),
+            h.to_be(),
+        ];
+        Ipv6Addr {
+            // All elements in `addr16` are big endian.
+            // SAFETY: `[u16; 8]` is always safe to transmute to `[u8; 16]`.
+            octets: unsafe { transmute::<_, [u8; 16]>(addr16) },
+        }
+    }
+
+    /// 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));
+    /// ```
+    #[stable(feature = "ip_constructors", since = "1.30.0")]
+    pub const LOCALHOST: Self = Ipv6Addr::new(0, 0, 0, 0, 0, 0, 0, 1);
+
+    /// 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));
+    /// ```
+    #[stable(feature = "ip_constructors", since = "1.30.0")]
+    pub const UNSPECIFIED: Self = Ipv6Addr::new(0, 0, 0, 0, 0, 0, 0, 0);
+
+    /// 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]);
+    /// ```
+    #[rustc_const_stable(feature = "const_ip_50", since = "1.50.0")]
+    #[stable(feature = "rust1", since = "1.0.0")]
+    #[must_use]
+    #[inline]
+    pub const fn segments(&self) -> [u16; 8] {
+        // All elements in `self.octets` must be big endian.
+        // SAFETY: `[u8; 16]` is always safe to transmute to `[u16; 8]`.
+        let [a, b, c, d, e, f, g, h] = unsafe { transmute::<_, [u16; 8]>(self.octets) };
+        // We want native endian u16
+        [
+            u16::from_be(a),
+            u16::from_be(b),
+            u16::from_be(c),
+            u16::from_be(d),
+            u16::from_be(e),
+            u16::from_be(f),
+            u16::from_be(g),
+            u16::from_be(h),
+        ]
+    }
+
+    /// Returns [`true`] for the special 'unspecified' address (`::`).
+    ///
+    /// This property is defined in [IETF RFC 4291].
+    ///
+    /// [IETF RFC 4291]: https://tools.ietf.org/html/rfc4291
+    ///
+    /// # 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);
+    /// ```
+    #[rustc_const_stable(feature = "const_ip_50", since = "1.50.0")]
+    #[stable(since = "1.7.0", feature = "ip_17")]
+    #[must_use]
+    #[inline]
+    pub const fn is_unspecified(&self) -> bool {
+        u128::from_be_bytes(self.octets()) == u128::from_be_bytes(Ipv6Addr::UNSPECIFIED.octets())
+    }
+
+    /// 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.
+    ///
+    /// [loopback address]: Ipv6Addr::LOCALHOST
+    /// [IETF RFC 4291 section 2.5.3]: https://tools.ietf.org/html/rfc4291#section-2.5.3
+    ///
+    /// # 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);
+    /// ```
+    #[rustc_const_stable(feature = "const_ip_50", since = "1.50.0")]
+    #[stable(since = "1.7.0", feature = "ip_17")]
+    #[must_use]
+    #[inline]
+    pub const fn is_loopback(&self) -> bool {
+        u128::from_be_bytes(self.octets()) == u128::from_be_bytes(Ipv6Addr::LOCALHOST.octets())
+    }
+
+    /// 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);
+    /// ```
+    #[rustc_const_unstable(feature = "const_ipv6", issue = "76205")]
+    #[unstable(feature = "ip", issue = "27709")]
+    #[must_use]
+    #[inline]
+    pub const fn is_global(&self) -> bool {
+        match self.multicast_scope() {
+            Some(Ipv6MulticastScope::Global) => true,
+            None => self.is_unicast_global(),
+            _ => false,
+        }
+    }
+
+    /// Returns [`true`] if this is a unique local address (`fc00::/7`).
+    ///
+    /// This property is defined in [IETF RFC 4193].
+    ///
+    /// [IETF RFC 4193]: https://tools.ietf.org/html/rfc4193
+    ///
+    /// # 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);
+    /// ```
+    #[rustc_const_unstable(feature = "const_ipv6", issue = "76205")]
+    #[unstable(feature = "ip", issue = "27709")]
+    #[must_use]
+    #[inline]
+    pub const fn is_unique_local(&self) -> bool {
+        (self.segments()[0] & 0xfe00) == 0xfc00
+    }
+
+    /// 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.
+    ///
+    /// [IETF RFC 4291]: https://tools.ietf.org/html/rfc4291
+    /// [multicast address]: Ipv6Addr::is_multicast
+    ///
+    /// # 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);
+    /// ```
+    #[rustc_const_unstable(feature = "const_ipv6", issue = "76205")]
+    #[unstable(feature = "ip", issue = "27709")]
+    #[must_use]
+    #[inline]
+    pub const fn is_unicast(&self) -> bool {
+        !self.is_multicast()
+    }
+
+    /// 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:
+    ///
+    /// ```text
+    /// | 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.
+    ///
+    /// [RFC 4291]: https://tools.ietf.org/html/rfc4291
+    /// [RFC 4291 section 2.4]: https://tools.ietf.org/html/rfc4291#section-2.4
+    /// [RFC 4291 section 2.5.3]: https://tools.ietf.org/html/rfc4291#section-2.5.3
+    /// [RFC 4291 section 2.5.6]: https://tools.ietf.org/html/rfc4291#section-2.5.6
+    /// [loopback address]: Ipv6Addr::LOCALHOST
+    ///
+    /// # 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);
+    /// ```
+    #[rustc_const_unstable(feature = "const_ipv6", issue = "76205")]
+    #[unstable(feature = "ip", issue = "27709")]
+    #[must_use]
+    #[inline]
+    pub const fn is_unicast_link_local(&self) -> bool {
+        (self.segments()[0] & 0xffc0) == 0xfe80
+    }
+
+    /// Returns [`true`] if this is an address reserved for documentation
+    /// (`2001:db8::/32`).
+    ///
+    /// This property is defined in [IETF RFC 3849].
+    ///
+    /// [IETF RFC 3849]: https://tools.ietf.org/html/rfc3849
+    ///
+    /// # 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);
+    /// ```
+    #[rustc_const_unstable(feature = "const_ipv6", issue = "76205")]
+    #[unstable(feature = "ip", issue = "27709")]
+    #[must_use]
+    #[inline]
+    pub const fn is_documentation(&self) -> bool {
+        (self.segments()[0] == 0x2001) && (self.segments()[1] == 0xdb8)
+    }
+
+    /// 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`.
+    ///
+    /// [IETF RFC 5180]: https://tools.ietf.org/html/rfc5180
+    /// [IETF RFC Errata 1752]: https://www.rfc-editor.org/errata_search.php?eid=1752
+    ///
+    /// ```
+    /// #![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);
+    /// ```
+    #[unstable(feature = "ip", issue = "27709")]
+    #[must_use]
+    #[inline]
+    pub const fn is_benchmarking(&self) -> bool {
+        (self.segments()[0] == 0x2001) && (self.segments()[1] == 0x2) && (self.segments()[2] == 0)
+    }
+
+    /// 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]
+    ///
+    /// ```no_rust
+    /// 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).
+    /// ```
+    ///
+    /// [RFC 4291 section 2.5.7]: https://tools.ietf.org/html/rfc4291#section-2.5.7
+    ///
+    /// # 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);
+    /// ```
+    #[rustc_const_unstable(feature = "const_ipv6", issue = "76205")]
+    #[unstable(feature = "ip", issue = "27709")]
+    #[must_use]
+    #[inline]
+    pub const fn is_unicast_global(&self) -> bool {
+        self.is_unicast()
+            && !self.is_loopback()
+            && !self.is_unicast_link_local()
+            && !self.is_unique_local()
+            && !self.is_unspecified()
+            && !self.is_documentation()
+    }
+
+    /// 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);
+    /// ```
+    #[rustc_const_unstable(feature = "const_ipv6", issue = "76205")]
+    #[unstable(feature = "ip", issue = "27709")]
+    #[must_use]
+    #[inline]
+    pub const fn multicast_scope(&self) -> Option<Ipv6MulticastScope> {
+        if self.is_multicast() {
+            match self.segments()[0] & 0x000f {
+                1 => Some(Ipv6MulticastScope::InterfaceLocal),
+                2 => Some(Ipv6MulticastScope::LinkLocal),
+                3 => Some(Ipv6MulticastScope::RealmLocal),
+                4 => Some(Ipv6MulticastScope::AdminLocal),
+                5 => Some(Ipv6MulticastScope::SiteLocal),
+                8 => Some(Ipv6MulticastScope::OrganizationLocal),
+                14 => Some(Ipv6MulticastScope::Global),
+                _ => None,
+            }
+        } else {
+            None
+        }
+    }
+
+    /// Returns [`true`] if this is a multicast address (`ff00::/8`).
+    ///
+    /// This property is defined by [IETF RFC 4291].
+    ///
+    /// [IETF RFC 4291]: https://tools.ietf.org/html/rfc4291
+    ///
+    /// # 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);
+    /// ```
+    #[rustc_const_stable(feature = "const_ip_50", since = "1.50.0")]
+    #[stable(since = "1.7.0", feature = "ip_17")]
+    #[must_use]
+    #[inline]
+    pub const fn is_multicast(&self) -> bool {
+        (self.segments()[0] & 0xff00) == 0xff00
+    }
+
+    /// 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`.
+    ///
+    /// [`IPv4` address]: Ipv4Addr
+    /// [IPv4-mapped]: Ipv6Addr
+    /// [IETF RFC 4291 section 2.5.5.2]: https://tools.ietf.org/html/rfc4291#section-2.5.5.2
+    ///
+    /// # 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);
+    /// ```
+    #[rustc_const_unstable(feature = "const_ipv6", issue = "76205")]
+    #[stable(feature = "ipv6_to_ipv4_mapped", since = "1.63.0")]
+    #[must_use = "this returns the result of the operation, \
+                  without modifying the original"]
+    #[inline]
+    pub const fn to_ipv4_mapped(&self) -> Option<Ipv4Addr> {
+        match self.octets() {
+            [0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0xff, 0xff, a, b, c, d] => {
+                Some(Ipv4Addr::new(a, b, c, d))
+            }
+            _ => None,
+        }
+    }
+
+    /// 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`.
+    ///
+    /// [`IPv4` address]: Ipv4Addr
+    /// [IPv4-compatible]: Ipv6Addr#ipv4-compatible-ipv6-addresses
+    /// [IPv4-mapped]: Ipv6Addr#ipv4-mapped-ipv6-addresses
+    /// [IETF RFC 4291 section 2.5.5.1]: https://tools.ietf.org/html/rfc4291#section-2.5.5.1
+    /// [IETF RFC 4291 section 2.5.5.2]: https://tools.ietf.org/html/rfc4291#section-2.5.5.2
+    ///
+    /// # 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)));
+    /// ```
+    #[rustc_const_stable(feature = "const_ip_50", since = "1.50.0")]
+    #[stable(feature = "rust1", since = "1.0.0")]
+    #[must_use = "this returns the result of the operation, \
+                  without modifying the original"]
+    #[inline]
+    pub const fn to_ipv4(&self) -> Option<Ipv4Addr> {
+        if let [0, 0, 0, 0, 0, 0 | 0xffff, ab, cd] = self.segments() {
+            let [a, b] = ab.to_be_bytes();
+            let [c, d] = cd.to_be_bytes();
+            Some(Ipv4Addr::new(a, b, c, d))
+        } else {
+            None
+        }
+    }
+
+    /// 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);
+    /// ```
+    #[rustc_const_unstable(feature = "const_ipv6", issue = "76205")]
+    #[unstable(feature = "ip", issue = "27709")]
+    #[must_use = "this returns the result of the operation, \
+                  without modifying the original"]
+    #[inline]
+    pub const fn to_canonical(&self) -> IpAddr {
+        if let Some(mapped) = self.to_ipv4_mapped() {
+            return IpAddr::V4(mapped);
+        }
+        IpAddr::V6(*self)
+    }
+
+    /// 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]);
+    /// ```
+    #[rustc_const_stable(feature = "const_ip_32", since = "1.32.0")]
+    #[stable(feature = "ipv6_to_octets", since = "1.12.0")]
+    #[must_use]
+    #[inline]
+    pub const fn octets(&self) -> [u8; 16] {
+        self.octets
+    }
+}
+
+/// Write an Ipv6Addr, conforming to the canonical style described by
+/// [RFC 5952](https://tools.ietf.org/html/rfc5952).
+#[stable(feature = "rust1", since = "1.0.0")]
+impl fmt::Display for Ipv6Addr {
+    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
+        // If there are no alignment requirements, write out the IP address to
+        // f. Otherwise, write it to a local buffer, then use f.pad.
+        if f.precision().is_none() && f.width().is_none() {
+            let segments = self.segments();
+
+            // Special case for :: and ::1; otherwise they get written with the
+            // IPv4 formatter
+            if self.is_unspecified() {
+                f.write_str("::")
+            } else if self.is_loopback() {
+                f.write_str("::1")
+            } else if let Some(ipv4) = self.to_ipv4() {
+                match segments[5] {
+                    // IPv4 Compatible address
+                    0 => write!(f, "::{}", ipv4),
+                    // IPv4 Mapped address
+                    0xffff => write!(f, "::ffff:{}", ipv4),
+                    _ => unreachable!(),
+                }
+            } else {
+                #[derive(Copy, Clone, Default)]
+                struct Span {
+                    start: usize,
+                    len: usize,
+                }
+
+                // Find the inner 0 span
+                let zeroes = {
+                    let mut longest = Span::default();
+                    let mut current = Span::default();
+
+                    for (i, &segment) in segments.iter().enumerate() {
+                        if segment == 0 {
+                            if current.len == 0 {
+                                current.start = i;
+                            }
+
+                            current.len += 1;
+
+                            if current.len > longest.len {
+                                longest = current;
+                            }
+                        } else {
+                            current = Span::default();
+                        }
+                    }
+
+                    longest
+                };
+
+                /// Write a colon-separated part of the address
+                #[inline]
+                fn fmt_subslice(f: &mut fmt::Formatter<'_>, chunk: &[u16]) -> fmt::Result {
+                    if let Some((first, tail)) = chunk.split_first() {
+                        write!(f, "{:x}", first)?;
+                        for segment in tail {
+                            f.write_char(':')?;
+                            write!(f, "{:x}", segment)?;
+                        }
+                    }
+                    Ok(())
+                }
+
+                if zeroes.len > 1 {
+                    fmt_subslice(f, &segments[..zeroes.start])?;
+                    f.write_str("::")?;
+                    fmt_subslice(f, &segments[zeroes.start + zeroes.len..])
+                } else {
+                    fmt_subslice(f, &segments)
+                }
+            }
+        } else {
+            // Slow path: write the address to a local buffer, then use f.pad.
+            // Defined recursively by using the fast path to write to the
+            // buffer.
+
+            // This is the largest possible size of an IPv6 address
+            const IPV6_BUF_LEN: usize = (4 * 8) + 7;
+            let mut buf = [0u8; IPV6_BUF_LEN];
+            let mut buf_slice = &mut buf[..];
+
+            // Note: This call to write should never fail, so unwrap is okay.
+            write!(buf_slice, "{}", self).unwrap();
+            let len = IPV6_BUF_LEN - buf_slice.len();
+
+            // This is safe because we know exactly what can be in this buffer
+            let buf = unsafe { crate::str::from_utf8_unchecked(&buf[..len]) };
+            f.pad(buf)
+        }
+    }
+}
+
+#[stable(feature = "rust1", since = "1.0.0")]
+impl fmt::Debug for Ipv6Addr {
+    fn fmt(&self, fmt: &mut fmt::Formatter<'_>) -> fmt::Result {
+        fmt::Display::fmt(self, fmt)
+    }
+}
+
+#[stable(feature = "ip_cmp", since = "1.16.0")]
+impl PartialEq<IpAddr> for Ipv6Addr {
+    #[inline]
+    fn eq(&self, other: &IpAddr) -> bool {
+        match other {
+            IpAddr::V4(_) => false,
+            IpAddr::V6(v6) => self == v6,
+        }
+    }
+}
+
+#[stable(feature = "ip_cmp", since = "1.16.0")]
+impl PartialEq<Ipv6Addr> for IpAddr {
+    #[inline]
+    fn eq(&self, other: &Ipv6Addr) -> bool {
+        match self {
+            IpAddr::V4(_) => false,
+            IpAddr::V6(v6) => v6 == other,
+        }
+    }
+}
+
+#[stable(feature = "rust1", since = "1.0.0")]
+impl PartialOrd for Ipv6Addr {
+    #[inline]
+    fn partial_cmp(&self, other: &Ipv6Addr) -> Option<Ordering> {
+        Some(self.cmp(other))
+    }
+}
+
+#[stable(feature = "ip_cmp", since = "1.16.0")]
+impl PartialOrd<Ipv6Addr> for IpAddr {
+    #[inline]
+    fn partial_cmp(&self, other: &Ipv6Addr) -> Option<Ordering> {
+        match self {
+            IpAddr::V4(_) => Some(Ordering::Less),
+            IpAddr::V6(v6) => v6.partial_cmp(other),
+        }
+    }
+}
+
+#[stable(feature = "ip_cmp", since = "1.16.0")]
+impl PartialOrd<IpAddr> for Ipv6Addr {
+    #[inline]
+    fn partial_cmp(&self, other: &IpAddr) -> Option<Ordering> {
+        match other {
+            IpAddr::V4(_) => Some(Ordering::Greater),
+            IpAddr::V6(v6) => self.partial_cmp(v6),
+        }
+    }
+}
+
+#[stable(feature = "rust1", since = "1.0.0")]
+impl Ord for Ipv6Addr {
+    #[inline]
+    fn cmp(&self, other: &Ipv6Addr) -> Ordering {
+        self.segments().cmp(&other.segments())
+    }
+}
+
+impl IntoInner<c::in6_addr> for Ipv6Addr {
+    fn into_inner(self) -> c::in6_addr {
+        c::in6_addr { s6_addr: self.octets }
+    }
+}
+impl FromInner<c::in6_addr> for Ipv6Addr {
+    #[inline]
+    fn from_inner(addr: c::in6_addr) -> Ipv6Addr {
+        Ipv6Addr { octets: addr.s6_addr }
+    }
+}
+
+#[stable(feature = "i128", since = "1.26.0")]
+impl From<Ipv6Addr> for 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));
+    /// ```
+    #[inline]
+    fn from(ip: Ipv6Addr) -> u128 {
+        u128::from_be_bytes(ip.octets)
+    }
+}
+#[stable(feature = "i128", since = "1.26.0")]
+impl From<u128> for 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);
+    /// ```
+    #[inline]
+    fn from(ip: u128) -> Ipv6Addr {
+        Ipv6Addr::from(ip.to_be_bytes())
+    }
+}
+
+#[stable(feature = "ipv6_from_octets", since = "1.9.0")]
+impl From<[u8; 16]> for 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
+    /// );
+    /// ```
+    #[inline]
+    fn from(octets: [u8; 16]) -> Ipv6Addr {
+        Ipv6Addr { octets }
+    }
+}
+
+#[stable(feature = "ipv6_from_segments", since = "1.16.0")]
+impl From<[u16; 8]> for 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
+    /// );
+    /// ```
+    #[inline]
+    fn from(segments: [u16; 8]) -> Ipv6Addr {
+        let [a, b, c, d, e, f, g, h] = segments;
+        Ipv6Addr::new(a, b, c, d, e, f, g, h)
+    }
+}
+
+#[stable(feature = "ip_from_slice", since = "1.17.0")]
+impl From<[u8; 16]> for IpAddr {
+    /// Creates an `IpAddr::V6` from a sixteen element byte array.
+    ///
+    /// # Examples
+    ///
+    /// ```
+    /// use std::net::{IpAddr, Ipv6Addr};
+    ///
+    /// let addr = IpAddr::from([
+    ///     25u8, 24u8, 23u8, 22u8, 21u8, 20u8, 19u8, 18u8,
+    ///     17u8, 16u8, 15u8, 14u8, 13u8, 12u8, 11u8, 10u8,
+    /// ]);
+    /// assert_eq!(
+    ///     IpAddr::V6(Ipv6Addr::new(
+    ///         0x1918, 0x1716,
+    ///         0x1514, 0x1312,
+    ///         0x1110, 0x0f0e,
+    ///         0x0d0c, 0x0b0a
+    ///     )),
+    ///     addr
+    /// );
+    /// ```
+    #[inline]
+    fn from(octets: [u8; 16]) -> IpAddr {
+        IpAddr::V6(Ipv6Addr::from(octets))
+    }
+}
+
+#[stable(feature = "ip_from_slice", since = "1.17.0")]
+impl From<[u16; 8]> for IpAddr {
+    /// Creates an `IpAddr::V6` from an eight element 16-bit array.
+    ///
+    /// # Examples
+    ///
+    /// ```
+    /// use std::net::{IpAddr, Ipv6Addr};
+    ///
+    /// let addr = IpAddr::from([
+    ///     525u16, 524u16, 523u16, 522u16,
+    ///     521u16, 520u16, 519u16, 518u16,
+    /// ]);
+    /// assert_eq!(
+    ///     IpAddr::V6(Ipv6Addr::new(
+    ///         0x20d, 0x20c,
+    ///         0x20b, 0x20a,
+    ///         0x209, 0x208,
+    ///         0x207, 0x206
+    ///     )),
+    ///     addr
+    /// );
+    /// ```
+    #[inline]
+    fn from(segments: [u16; 8]) -> IpAddr {
+        IpAddr::V6(Ipv6Addr::from(segments))
+    }
+}
diff --git a/library/std/src/net/ip/tests.rs b/library/std/src/net/ip/tests.rs
new file mode 100644
index 000000000..c29509331
--- /dev/null
+++ b/library/std/src/net/ip/tests.rs
@@ -0,0 +1,969 @@
+use crate::net::test::{sa4, sa6, tsa};
+use crate::net::*;
+use crate::str::FromStr;
+
+#[test]
+fn test_from_str_ipv4() {
+    assert_eq!(Ok(Ipv4Addr::new(127, 0, 0, 1)), "127.0.0.1".parse());
+    assert_eq!(Ok(Ipv4Addr::new(255, 255, 255, 255)), "255.255.255.255".parse());
+    assert_eq!(Ok(Ipv4Addr::new(0, 0, 0, 0)), "0.0.0.0".parse());
+
+    // out of range
+    let none: Option<Ipv4Addr> = "256.0.0.1".parse().ok();
+    assert_eq!(None, none);
+    // too short
+    let none: Option<Ipv4Addr> = "255.0.0".parse().ok();
+    assert_eq!(None, none);
+    // too long
+    let none: Option<Ipv4Addr> = "255.0.0.1.2".parse().ok();
+    assert_eq!(None, none);
+    // no number between dots
+    let none: Option<Ipv4Addr> = "255.0..1".parse().ok();
+    assert_eq!(None, none);
+    // octal
+    let none: Option<Ipv4Addr> = "255.0.0.01".parse().ok();
+    assert_eq!(None, none);
+    // octal zero
+    let none: Option<Ipv4Addr> = "255.0.0.00".parse().ok();
+    assert_eq!(None, none);
+    let none: Option<Ipv4Addr> = "255.0.00.0".parse().ok();
+    assert_eq!(None, none);
+}
+
+#[test]
+fn test_from_str_ipv6() {
+    assert_eq!(Ok(Ipv6Addr::new(0, 0, 0, 0, 0, 0, 0, 0)), "0:0:0:0:0:0:0:0".parse());
+    assert_eq!(Ok(Ipv6Addr::new(0, 0, 0, 0, 0, 0, 0, 1)), "0:0:0:0:0:0:0:1".parse());
+
+    assert_eq!(Ok(Ipv6Addr::new(0, 0, 0, 0, 0, 0, 0, 1)), "::1".parse());
+    assert_eq!(Ok(Ipv6Addr::new(0, 0, 0, 0, 0, 0, 0, 0)), "::".parse());
+
+    assert_eq!(Ok(Ipv6Addr::new(0x2a02, 0x6b8, 0, 0, 0, 0, 0x11, 0x11)), "2a02:6b8::11:11".parse());
+
+    // too long group
+    let none: Option<Ipv6Addr> = "::00000".parse().ok();
+    assert_eq!(None, none);
+    // too short
+    let none: Option<Ipv6Addr> = "1:2:3:4:5:6:7".parse().ok();
+    assert_eq!(None, none);
+    // too long
+    let none: Option<Ipv6Addr> = "1:2:3:4:5:6:7:8:9".parse().ok();
+    assert_eq!(None, none);
+    // triple colon
+    let none: Option<Ipv6Addr> = "1:2:::6:7:8".parse().ok();
+    assert_eq!(None, none);
+    // two double colons
+    let none: Option<Ipv6Addr> = "1:2::6::8".parse().ok();
+    assert_eq!(None, none);
+    // `::` indicating zero groups of zeros
+    let none: Option<Ipv6Addr> = "1:2:3:4::5:6:7:8".parse().ok();
+    assert_eq!(None, none);
+}
+
+#[test]
+fn test_from_str_ipv4_in_ipv6() {
+    assert_eq!(Ok(Ipv6Addr::new(0, 0, 0, 0, 0, 0, 49152, 545)), "::192.0.2.33".parse());
+    assert_eq!(Ok(Ipv6Addr::new(0, 0, 0, 0, 0, 0xFFFF, 49152, 545)), "::FFFF:192.0.2.33".parse());
+    assert_eq!(
+        Ok(Ipv6Addr::new(0x64, 0xff9b, 0, 0, 0, 0, 49152, 545)),
+        "64:ff9b::192.0.2.33".parse()
+    );
+    assert_eq!(
+        Ok(Ipv6Addr::new(0x2001, 0xdb8, 0x122, 0xc000, 0x2, 0x2100, 49152, 545)),
+        "2001:db8:122:c000:2:2100:192.0.2.33".parse()
+    );
+
+    // colon after v4
+    let none: Option<Ipv4Addr> = "::127.0.0.1:".parse().ok();
+    assert_eq!(None, none);
+    // not enough groups
+    let none: Option<Ipv6Addr> = "1:2:3:4:5:127.0.0.1".parse().ok();
+    assert_eq!(None, none);
+    // too many groups
+    let none: Option<Ipv6Addr> = "1:2:3:4:5:6:7:127.0.0.1".parse().ok();
+    assert_eq!(None, none);
+}
+
+#[test]
+fn test_from_str_socket_addr() {
+    assert_eq!(Ok(sa4(Ipv4Addr::new(77, 88, 21, 11), 80)), "77.88.21.11:80".parse());
+    assert_eq!(Ok(SocketAddrV4::new(Ipv4Addr::new(77, 88, 21, 11), 80)), "77.88.21.11:80".parse());
+    assert_eq!(
+        Ok(sa6(Ipv6Addr::new(0x2a02, 0x6b8, 0, 1, 0, 0, 0, 1), 53)),
+        "[2a02:6b8:0:1::1]:53".parse()
+    );
+    assert_eq!(
+        Ok(SocketAddrV6::new(Ipv6Addr::new(0x2a02, 0x6b8, 0, 1, 0, 0, 0, 1), 53, 0, 0)),
+        "[2a02:6b8:0:1::1]:53".parse()
+    );
+    assert_eq!(Ok(sa6(Ipv6Addr::new(0, 0, 0, 0, 0, 0, 0x7F00, 1), 22)), "[::127.0.0.1]:22".parse());
+    assert_eq!(
+        Ok(SocketAddrV6::new(Ipv6Addr::new(0, 0, 0, 0, 0, 0, 0x7F00, 1), 22, 0, 0)),
+        "[::127.0.0.1]:22".parse()
+    );
+
+    // without port
+    let none: Option<SocketAddr> = "127.0.0.1".parse().ok();
+    assert_eq!(None, none);
+    // without port
+    let none: Option<SocketAddr> = "127.0.0.1:".parse().ok();
+    assert_eq!(None, none);
+    // wrong brackets around v4
+    let none: Option<SocketAddr> = "[127.0.0.1]:22".parse().ok();
+    assert_eq!(None, none);
+    // port out of range
+    let none: Option<SocketAddr> = "127.0.0.1:123456".parse().ok();
+    assert_eq!(None, none);
+}
+
+#[test]
+fn ipv4_addr_to_string() {
+    assert_eq!(Ipv4Addr::new(127, 0, 0, 1).to_string(), "127.0.0.1");
+    // Short address
+    assert_eq!(Ipv4Addr::new(1, 1, 1, 1).to_string(), "1.1.1.1");
+    // Long address
+    assert_eq!(Ipv4Addr::new(127, 127, 127, 127).to_string(), "127.127.127.127");
+
+    // Test padding
+    assert_eq!(&format!("{:16}", Ipv4Addr::new(1, 1, 1, 1)), "1.1.1.1         ");
+    assert_eq!(&format!("{:>16}", Ipv4Addr::new(1, 1, 1, 1)), "         1.1.1.1");
+}
+
+#[test]
+fn ipv6_addr_to_string() {
+    // ipv4-mapped address
+    let a1 = Ipv6Addr::new(0, 0, 0, 0, 0, 0xffff, 0xc000, 0x280);
+    assert_eq!(a1.to_string(), "::ffff:192.0.2.128");
+
+    // ipv4-compatible address
+    let a1 = Ipv6Addr::new(0, 0, 0, 0, 0, 0, 0xc000, 0x280);
+    assert_eq!(a1.to_string(), "::192.0.2.128");
+
+    // v6 address with no zero segments
+    assert_eq!(Ipv6Addr::new(8, 9, 10, 11, 12, 13, 14, 15).to_string(), "8:9:a:b:c:d:e:f");
+
+    // longest possible IPv6 length
+    assert_eq!(
+        Ipv6Addr::new(0x1111, 0x2222, 0x3333, 0x4444, 0x5555, 0x6666, 0x7777, 0x8888).to_string(),
+        "1111:2222:3333:4444:5555:6666:7777:8888"
+    );
+    // padding
+    assert_eq!(&format!("{:20}", Ipv6Addr::new(1, 2, 3, 4, 5, 6, 7, 8)), "1:2:3:4:5:6:7:8     ");
+    assert_eq!(&format!("{:>20}", Ipv6Addr::new(1, 2, 3, 4, 5, 6, 7, 8)), "     1:2:3:4:5:6:7:8");
+
+    // reduce a single run of zeros
+    assert_eq!(
+        "ae::ffff:102:304",
+        Ipv6Addr::new(0xae, 0, 0, 0, 0, 0xffff, 0x0102, 0x0304).to_string()
+    );
+
+    // don't reduce just a single zero segment
+    assert_eq!("1:2:3:4:5:6:0:8", Ipv6Addr::new(1, 2, 3, 4, 5, 6, 0, 8).to_string());
+
+    // 'any' address
+    assert_eq!("::", Ipv6Addr::new(0, 0, 0, 0, 0, 0, 0, 0).to_string());
+
+    // loopback address
+    assert_eq!("::1", Ipv6Addr::new(0, 0, 0, 0, 0, 0, 0, 1).to_string());
+
+    // ends in zeros
+    assert_eq!("1::", Ipv6Addr::new(1, 0, 0, 0, 0, 0, 0, 0).to_string());
+
+    // two runs of zeros, second one is longer
+    assert_eq!("1:0:0:4::8", Ipv6Addr::new(1, 0, 0, 4, 0, 0, 0, 8).to_string());
+
+    // two runs of zeros, equal length
+    assert_eq!("1::4:5:0:0:8", Ipv6Addr::new(1, 0, 0, 4, 5, 0, 0, 8).to_string());
+
+    // don't prefix `0x` to each segment in `dbg!`.
+    assert_eq!("1::4:5:0:0:8", &format!("{:#?}", Ipv6Addr::new(1, 0, 0, 4, 5, 0, 0, 8)));
+}
+
+#[test]
+fn ipv4_to_ipv6() {
+    assert_eq!(
+        Ipv6Addr::new(0, 0, 0, 0, 0, 0xffff, 0x1234, 0x5678),
+        Ipv4Addr::new(0x12, 0x34, 0x56, 0x78).to_ipv6_mapped()
+    );
+    assert_eq!(
+        Ipv6Addr::new(0, 0, 0, 0, 0, 0, 0x1234, 0x5678),
+        Ipv4Addr::new(0x12, 0x34, 0x56, 0x78).to_ipv6_compatible()
+    );
+}
+
+#[test]
+fn ipv6_to_ipv4_mapped() {
+    assert_eq!(
+        Ipv6Addr::new(0, 0, 0, 0, 0, 0xffff, 0x1234, 0x5678).to_ipv4_mapped(),
+        Some(Ipv4Addr::new(0x12, 0x34, 0x56, 0x78))
+    );
+    assert_eq!(Ipv6Addr::new(0, 0, 0, 0, 0, 0, 0x1234, 0x5678).to_ipv4_mapped(), None);
+}
+
+#[test]
+fn ipv6_to_ipv4() {
+    assert_eq!(
+        Ipv6Addr::new(0, 0, 0, 0, 0, 0xffff, 0x1234, 0x5678).to_ipv4(),
+        Some(Ipv4Addr::new(0x12, 0x34, 0x56, 0x78))
+    );
+    assert_eq!(
+        Ipv6Addr::new(0, 0, 0, 0, 0, 0, 0x1234, 0x5678).to_ipv4(),
+        Some(Ipv4Addr::new(0x12, 0x34, 0x56, 0x78))
+    );
+    assert_eq!(Ipv6Addr::new(0, 0, 1, 0, 0, 0, 0x1234, 0x5678).to_ipv4(), None);
+}
+
+#[test]
+fn ip_properties() {
+    macro_rules! ip {
+        ($s:expr) => {
+            IpAddr::from_str($s).unwrap()
+        };
+    }
+
+    macro_rules! check {
+        ($s:expr) => {
+            check!($s, 0);
+        };
+
+        ($s:expr, $mask:expr) => {{
+            let unspec: u8 = 1 << 0;
+            let loopback: u8 = 1 << 1;
+            let global: u8 = 1 << 2;
+            let multicast: u8 = 1 << 3;
+            let doc: u8 = 1 << 4;
+            let benchmarking: u8 = 1 << 5;
+
+            if ($mask & unspec) == unspec {
+                assert!(ip!($s).is_unspecified());
+            } else {
+                assert!(!ip!($s).is_unspecified());
+            }
+
+            if ($mask & loopback) == loopback {
+                assert!(ip!($s).is_loopback());
+            } else {
+                assert!(!ip!($s).is_loopback());
+            }
+
+            if ($mask & global) == global {
+                assert!(ip!($s).is_global());
+            } else {
+                assert!(!ip!($s).is_global());
+            }
+
+            if ($mask & multicast) == multicast {
+                assert!(ip!($s).is_multicast());
+            } else {
+                assert!(!ip!($s).is_multicast());
+            }
+
+            if ($mask & doc) == doc {
+                assert!(ip!($s).is_documentation());
+            } else {
+                assert!(!ip!($s).is_documentation());
+            }
+
+            if ($mask & benchmarking) == benchmarking {
+                assert!(ip!($s).is_benchmarking());
+            } else {
+                assert!(!ip!($s).is_benchmarking());
+            }
+        }};
+    }
+
+    let unspec: u8 = 1 << 0;
+    let loopback: u8 = 1 << 1;
+    let global: u8 = 1 << 2;
+    let multicast: u8 = 1 << 3;
+    let doc: u8 = 1 << 4;
+    let benchmarking: u8 = 1 << 5;
+
+    check!("0.0.0.0", unspec);
+    check!("0.0.0.1");
+    check!("0.1.0.0");
+    check!("10.9.8.7");
+    check!("127.1.2.3", loopback);
+    check!("172.31.254.253");
+    check!("169.254.253.242");
+    check!("192.0.2.183", doc);
+    check!("192.1.2.183", global);
+    check!("192.168.254.253");
+    check!("198.51.100.0", doc);
+    check!("203.0.113.0", doc);
+    check!("203.2.113.0", global);
+    check!("224.0.0.0", global | multicast);
+    check!("239.255.255.255", global | multicast);
+    check!("255.255.255.255");
+    // make sure benchmarking addresses are not global
+    check!("198.18.0.0", benchmarking);
+    check!("198.18.54.2", benchmarking);
+    check!("198.19.255.255", benchmarking);
+    // make sure addresses reserved for protocol assignment are not global
+    check!("192.0.0.0");
+    check!("192.0.0.255");
+    check!("192.0.0.100");
+    // make sure reserved addresses are not global
+    check!("240.0.0.0");
+    check!("251.54.1.76");
+    check!("254.255.255.255");
+    // make sure shared addresses are not global
+    check!("100.64.0.0");
+    check!("100.127.255.255");
+    check!("100.100.100.0");
+
+    check!("::", unspec);
+    check!("::1", loopback);
+    check!("::0.0.0.2", global);
+    check!("1::", global);
+    check!("fc00::");
+    check!("fdff:ffff::");
+    check!("fe80:ffff::");
+    check!("febf:ffff::");
+    check!("fec0::", global);
+    check!("ff01::", multicast);
+    check!("ff02::", multicast);
+    check!("ff03::", multicast);
+    check!("ff04::", multicast);
+    check!("ff05::", multicast);
+    check!("ff08::", multicast);
+    check!("ff0e::", global | multicast);
+    check!("2001:db8:85a3::8a2e:370:7334", doc);
+    check!("2001:2::ac32:23ff:21", global | benchmarking);
+    check!("102:304:506:708:90a:b0c:d0e:f10", global);
+}
+
+#[test]
+fn ipv4_properties() {
+    macro_rules! ip {
+        ($s:expr) => {
+            Ipv4Addr::from_str($s).unwrap()
+        };
+    }
+
+    macro_rules! check {
+        ($s:expr) => {
+            check!($s, 0);
+        };
+
+        ($s:expr, $mask:expr) => {{
+            let unspec: u16 = 1 << 0;
+            let loopback: u16 = 1 << 1;
+            let private: u16 = 1 << 2;
+            let link_local: u16 = 1 << 3;
+            let global: u16 = 1 << 4;
+            let multicast: u16 = 1 << 5;
+            let broadcast: u16 = 1 << 6;
+            let documentation: u16 = 1 << 7;
+            let benchmarking: u16 = 1 << 8;
+            let reserved: u16 = 1 << 10;
+            let shared: u16 = 1 << 11;
+
+            if ($mask & unspec) == unspec {
+                assert!(ip!($s).is_unspecified());
+            } else {
+                assert!(!ip!($s).is_unspecified());
+            }
+
+            if ($mask & loopback) == loopback {
+                assert!(ip!($s).is_loopback());
+            } else {
+                assert!(!ip!($s).is_loopback());
+            }
+
+            if ($mask & private) == private {
+                assert!(ip!($s).is_private());
+            } else {
+                assert!(!ip!($s).is_private());
+            }
+
+            if ($mask & link_local) == link_local {
+                assert!(ip!($s).is_link_local());
+            } else {
+                assert!(!ip!($s).is_link_local());
+            }
+
+            if ($mask & global) == global {
+                assert!(ip!($s).is_global());
+            } else {
+                assert!(!ip!($s).is_global());
+            }
+
+            if ($mask & multicast) == multicast {
+                assert!(ip!($s).is_multicast());
+            } else {
+                assert!(!ip!($s).is_multicast());
+            }
+
+            if ($mask & broadcast) == broadcast {
+                assert!(ip!($s).is_broadcast());
+            } else {
+                assert!(!ip!($s).is_broadcast());
+            }
+
+            if ($mask & documentation) == documentation {
+                assert!(ip!($s).is_documentation());
+            } else {
+                assert!(!ip!($s).is_documentation());
+            }
+
+            if ($mask & benchmarking) == benchmarking {
+                assert!(ip!($s).is_benchmarking());
+            } else {
+                assert!(!ip!($s).is_benchmarking());
+            }
+
+            if ($mask & reserved) == reserved {
+                assert!(ip!($s).is_reserved());
+            } else {
+                assert!(!ip!($s).is_reserved());
+            }
+
+            if ($mask & shared) == shared {
+                assert!(ip!($s).is_shared());
+            } else {
+                assert!(!ip!($s).is_shared());
+            }
+        }};
+    }
+
+    let unspec: u16 = 1 << 0;
+    let loopback: u16 = 1 << 1;
+    let private: u16 = 1 << 2;
+    let link_local: u16 = 1 << 3;
+    let global: u16 = 1 << 4;
+    let multicast: u16 = 1 << 5;
+    let broadcast: u16 = 1 << 6;
+    let documentation: u16 = 1 << 7;
+    let benchmarking: u16 = 1 << 8;
+    let reserved: u16 = 1 << 10;
+    let shared: u16 = 1 << 11;
+
+    check!("0.0.0.0", unspec);
+    check!("0.0.0.1");
+    check!("0.1.0.0");
+    check!("10.9.8.7", private);
+    check!("127.1.2.3", loopback);
+    check!("172.31.254.253", private);
+    check!("169.254.253.242", link_local);
+    check!("192.0.2.183", documentation);
+    check!("192.1.2.183", global);
+    check!("192.168.254.253", private);
+    check!("198.51.100.0", documentation);
+    check!("203.0.113.0", documentation);
+    check!("203.2.113.0", global);
+    check!("224.0.0.0", global | multicast);
+    check!("239.255.255.255", global | multicast);
+    check!("255.255.255.255", broadcast);
+    check!("198.18.0.0", benchmarking);
+    check!("198.18.54.2", benchmarking);
+    check!("198.19.255.255", benchmarking);
+    check!("192.0.0.0");
+    check!("192.0.0.255");
+    check!("192.0.0.100");
+    check!("240.0.0.0", reserved);
+    check!("251.54.1.76", reserved);
+    check!("254.255.255.255", reserved);
+    check!("100.64.0.0", shared);
+    check!("100.127.255.255", shared);
+    check!("100.100.100.0", shared);
+}
+
+#[test]
+fn ipv6_properties() {
+    macro_rules! ip {
+        ($s:expr) => {
+            Ipv6Addr::from_str($s).unwrap()
+        };
+    }
+
+    macro_rules! check {
+        ($s:expr, &[$($octet:expr),*], $mask:expr) => {
+            assert_eq!($s, ip!($s).to_string());
+            let octets = &[$($octet),*];
+            assert_eq!(&ip!($s).octets(), octets);
+            assert_eq!(Ipv6Addr::from(*octets), ip!($s));
+
+            let unspecified: u32 = 1 << 0;
+            let loopback: u32 = 1 << 1;
+            let unique_local: u32 = 1 << 2;
+            let global: u32 = 1 << 3;
+            let unicast_link_local: u32 = 1 << 4;
+            let unicast_global: u32 = 1 << 7;
+            let documentation: u32 = 1 << 8;
+            let benchmarking: u32 = 1 << 16;
+            let multicast_interface_local: u32 = 1 << 9;
+            let multicast_link_local: u32 = 1 << 10;
+            let multicast_realm_local: u32 = 1 << 11;
+            let multicast_admin_local: u32 = 1 << 12;
+            let multicast_site_local: u32 = 1 << 13;
+            let multicast_organization_local: u32 = 1 << 14;
+            let multicast_global: u32 = 1 << 15;
+            let multicast: u32 = multicast_interface_local
+                | multicast_admin_local
+                | multicast_global
+                | multicast_link_local
+                | multicast_realm_local
+                | multicast_site_local
+                | multicast_organization_local;
+
+            if ($mask & unspecified) == unspecified {
+                assert!(ip!($s).is_unspecified());
+            } else {
+                assert!(!ip!($s).is_unspecified());
+            }
+            if ($mask & loopback) == loopback {
+                assert!(ip!($s).is_loopback());
+            } else {
+                assert!(!ip!($s).is_loopback());
+            }
+            if ($mask & unique_local) == unique_local {
+                assert!(ip!($s).is_unique_local());
+            } else {
+                assert!(!ip!($s).is_unique_local());
+            }
+            if ($mask & global) == global {
+                assert!(ip!($s).is_global());
+            } else {
+                assert!(!ip!($s).is_global());
+            }
+            if ($mask & unicast_link_local) == unicast_link_local {
+                assert!(ip!($s).is_unicast_link_local());
+            } else {
+                assert!(!ip!($s).is_unicast_link_local());
+            }
+            if ($mask & unicast_global) == unicast_global {
+                assert!(ip!($s).is_unicast_global());
+            } else {
+                assert!(!ip!($s).is_unicast_global());
+            }
+            if ($mask & documentation) == documentation {
+                assert!(ip!($s).is_documentation());
+            } else {
+                assert!(!ip!($s).is_documentation());
+            }
+            if ($mask & benchmarking) == benchmarking {
+                assert!(ip!($s).is_benchmarking());
+            } else {
+                assert!(!ip!($s).is_benchmarking());
+            }
+            if ($mask & multicast) != 0 {
+                assert!(ip!($s).multicast_scope().is_some());
+                assert!(ip!($s).is_multicast());
+            } else {
+                assert!(ip!($s).multicast_scope().is_none());
+                assert!(!ip!($s).is_multicast());
+            }
+            if ($mask & multicast_interface_local) == multicast_interface_local {
+                assert_eq!(ip!($s).multicast_scope().unwrap(),
+                           Ipv6MulticastScope::InterfaceLocal);
+            }
+            if ($mask & multicast_link_local) == multicast_link_local {
+                assert_eq!(ip!($s).multicast_scope().unwrap(),
+                           Ipv6MulticastScope::LinkLocal);
+            }
+            if ($mask & multicast_realm_local) == multicast_realm_local {
+                assert_eq!(ip!($s).multicast_scope().unwrap(),
+                           Ipv6MulticastScope::RealmLocal);
+            }
+            if ($mask & multicast_admin_local) == multicast_admin_local {
+                assert_eq!(ip!($s).multicast_scope().unwrap(),
+                           Ipv6MulticastScope::AdminLocal);
+            }
+            if ($mask & multicast_site_local) == multicast_site_local {
+                assert_eq!(ip!($s).multicast_scope().unwrap(),
+                           Ipv6MulticastScope::SiteLocal);
+            }
+            if ($mask & multicast_organization_local) == multicast_organization_local {
+                assert_eq!(ip!($s).multicast_scope().unwrap(),
+                           Ipv6MulticastScope::OrganizationLocal);
+            }
+            if ($mask & multicast_global) == multicast_global {
+                assert_eq!(ip!($s).multicast_scope().unwrap(),
+                           Ipv6MulticastScope::Global);
+            }
+        }
+    }
+
+    let unspecified: u32 = 1 << 0;
+    let loopback: u32 = 1 << 1;
+    let unique_local: u32 = 1 << 2;
+    let global: u32 = 1 << 3;
+    let unicast_link_local: u32 = 1 << 4;
+    let unicast_global: u32 = 1 << 7;
+    let documentation: u32 = 1 << 8;
+    let benchmarking: u32 = 1 << 16;
+    let multicast_interface_local: u32 = 1 << 9;
+    let multicast_link_local: u32 = 1 << 10;
+    let multicast_realm_local: u32 = 1 << 11;
+    let multicast_admin_local: u32 = 1 << 12;
+    let multicast_site_local: u32 = 1 << 13;
+    let multicast_organization_local: u32 = 1 << 14;
+    let multicast_global: u32 = 1 << 15;
+
+    check!("::", &[0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0], unspecified);
+
+    check!("::1", &[0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1], loopback);
+
+    check!("::0.0.0.2", &[0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 2], global | unicast_global);
+
+    check!("1::", &[0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0], global | unicast_global);
+
+    check!("fc00::", &[0xfc, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0], unique_local);
+
+    check!(
+        "fdff:ffff::",
+        &[0xfd, 0xff, 0xff, 0xff, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0],
+        unique_local
+    );
+
+    check!(
+        "fe80:ffff::",
+        &[0xfe, 0x80, 0xff, 0xff, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0],
+        unicast_link_local
+    );
+
+    check!("fe80::", &[0xfe, 0x80, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0], unicast_link_local);
+
+    check!(
+        "febf:ffff::",
+        &[0xfe, 0xbf, 0xff, 0xff, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0],
+        unicast_link_local
+    );
+
+    check!("febf::", &[0xfe, 0xbf, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0], unicast_link_local);
+
+    check!(
+        "febf:ffff:ffff:ffff:ffff:ffff:ffff:ffff",
+        &[
+            0xfe, 0xbf, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff,
+            0xff, 0xff
+        ],
+        unicast_link_local
+    );
+
+    check!(
+        "fe80::ffff:ffff:ffff:ffff",
+        &[
+            0xfe, 0x80, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff,
+            0xff, 0xff
+        ],
+        unicast_link_local
+    );
+
+    check!(
+        "fe80:0:0:1::",
+        &[0xfe, 0x80, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0],
+        unicast_link_local
+    );
+
+    check!(
+        "fec0::",
+        &[0xfe, 0xc0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0],
+        unicast_global | global
+    );
+
+    check!(
+        "ff01::",
+        &[0xff, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0],
+        multicast_interface_local
+    );
+
+    check!("ff02::", &[0xff, 2, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0], multicast_link_local);
+
+    check!("ff03::", &[0xff, 3, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0], multicast_realm_local);
+
+    check!("ff04::", &[0xff, 4, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0], multicast_admin_local);
+
+    check!("ff05::", &[0xff, 5, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0], multicast_site_local);
+
+    check!(
+        "ff08::",
+        &[0xff, 8, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0],
+        multicast_organization_local
+    );
+
+    check!(
+        "ff0e::",
+        &[0xff, 0xe, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0],
+        multicast_global | global
+    );
+
+    check!(
+        "2001:db8:85a3::8a2e:370:7334",
+        &[0x20, 1, 0xd, 0xb8, 0x85, 0xa3, 0, 0, 0, 0, 0x8a, 0x2e, 3, 0x70, 0x73, 0x34],
+        documentation
+    );
+
+    check!(
+        "2001:2::ac32:23ff:21",
+        &[0x20, 1, 0, 2, 0, 0, 0, 0, 0, 0, 0xac, 0x32, 0x23, 0xff, 0, 0x21],
+        global | unicast_global | benchmarking
+    );
+
+    check!(
+        "102:304:506:708:90a:b0c:d0e:f10",
+        &[1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16],
+        global | unicast_global
+    );
+}
+
+#[test]
+fn to_socket_addr_socketaddr() {
+    let a = sa4(Ipv4Addr::new(77, 88, 21, 11), 12345);
+    assert_eq!(Ok(vec![a]), tsa(a));
+}
+
+#[test]
+fn test_ipv4_to_int() {
+    let a = Ipv4Addr::new(0x11, 0x22, 0x33, 0x44);
+    assert_eq!(u32::from(a), 0x11223344);
+}
+
+#[test]
+fn test_int_to_ipv4() {
+    let a = Ipv4Addr::new(0x11, 0x22, 0x33, 0x44);
+    assert_eq!(Ipv4Addr::from(0x11223344), a);
+}
+
+#[test]
+fn test_ipv6_to_int() {
+    let a = Ipv6Addr::new(0x1122, 0x3344, 0x5566, 0x7788, 0x99aa, 0xbbcc, 0xddee, 0xff11);
+    assert_eq!(u128::from(a), 0x112233445566778899aabbccddeeff11u128);
+}
+
+#[test]
+fn test_int_to_ipv6() {
+    let a = Ipv6Addr::new(0x1122, 0x3344, 0x5566, 0x7788, 0x99aa, 0xbbcc, 0xddee, 0xff11);
+    assert_eq!(Ipv6Addr::from(0x112233445566778899aabbccddeeff11u128), a);
+}
+
+#[test]
+fn ipv4_from_constructors() {
+    assert_eq!(Ipv4Addr::LOCALHOST, Ipv4Addr::new(127, 0, 0, 1));
+    assert!(Ipv4Addr::LOCALHOST.is_loopback());
+    assert_eq!(Ipv4Addr::UNSPECIFIED, Ipv4Addr::new(0, 0, 0, 0));
+    assert!(Ipv4Addr::UNSPECIFIED.is_unspecified());
+    assert_eq!(Ipv4Addr::BROADCAST, Ipv4Addr::new(255, 255, 255, 255));
+    assert!(Ipv4Addr::BROADCAST.is_broadcast());
+}
+
+#[test]
+fn ipv6_from_constructors() {
+    assert_eq!(Ipv6Addr::LOCALHOST, Ipv6Addr::new(0, 0, 0, 0, 0, 0, 0, 1));
+    assert!(Ipv6Addr::LOCALHOST.is_loopback());
+    assert_eq!(Ipv6Addr::UNSPECIFIED, Ipv6Addr::new(0, 0, 0, 0, 0, 0, 0, 0));
+    assert!(Ipv6Addr::UNSPECIFIED.is_unspecified());
+}
+
+#[test]
+fn ipv4_from_octets() {
+    assert_eq!(Ipv4Addr::from([127, 0, 0, 1]), Ipv4Addr::new(127, 0, 0, 1))
+}
+
+#[test]
+fn ipv6_from_segments() {
+    let from_u16s =
+        Ipv6Addr::from([0x0011, 0x2233, 0x4455, 0x6677, 0x8899, 0xaabb, 0xccdd, 0xeeff]);
+    let new = Ipv6Addr::new(0x0011, 0x2233, 0x4455, 0x6677, 0x8899, 0xaabb, 0xccdd, 0xeeff);
+    assert_eq!(new, from_u16s);
+}
+
+#[test]
+fn ipv6_from_octets() {
+    let from_u16s =
+        Ipv6Addr::from([0x0011, 0x2233, 0x4455, 0x6677, 0x8899, 0xaabb, 0xccdd, 0xeeff]);
+    let from_u8s = Ipv6Addr::from([
+        0x00, 0x11, 0x22, 0x33, 0x44, 0x55, 0x66, 0x77, 0x88, 0x99, 0xaa, 0xbb, 0xcc, 0xdd, 0xee,
+        0xff,
+    ]);
+    assert_eq!(from_u16s, from_u8s);
+}
+
+#[test]
+fn cmp() {
+    let v41 = Ipv4Addr::new(100, 64, 3, 3);
+    let v42 = Ipv4Addr::new(192, 0, 2, 2);
+    let v61 = "2001:db8:f00::1002".parse::<Ipv6Addr>().unwrap();
+    let v62 = "2001:db8:f00::2001".parse::<Ipv6Addr>().unwrap();
+    assert!(v41 < v42);
+    assert!(v61 < v62);
+
+    assert_eq!(v41, IpAddr::V4(v41));
+    assert_eq!(v61, IpAddr::V6(v61));
+    assert!(v41 != IpAddr::V4(v42));
+    assert!(v61 != IpAddr::V6(v62));
+
+    assert!(v41 < IpAddr::V4(v42));
+    assert!(v61 < IpAddr::V6(v62));
+    assert!(IpAddr::V4(v41) < v42);
+    assert!(IpAddr::V6(v61) < v62);
+
+    assert!(v41 < IpAddr::V6(v61));
+    assert!(IpAddr::V4(v41) < v61);
+}
+
+#[test]
+fn is_v4() {
+    let ip = IpAddr::V4(Ipv4Addr::new(100, 64, 3, 3));
+    assert!(ip.is_ipv4());
+    assert!(!ip.is_ipv6());
+}
+
+#[test]
+fn is_v6() {
+    let ip = IpAddr::V6(Ipv6Addr::new(0, 0, 0, 0, 0, 0xffff, 0x1234, 0x5678));
+    assert!(!ip.is_ipv4());
+    assert!(ip.is_ipv6());
+}
+
+#[test]
+fn ipv4_const() {
+    // test that the methods of `Ipv4Addr` are usable in a const context
+
+    const IP_ADDRESS: Ipv4Addr = Ipv4Addr::new(127, 0, 0, 1);
+    assert_eq!(IP_ADDRESS, Ipv4Addr::LOCALHOST);
+
+    const OCTETS: [u8; 4] = IP_ADDRESS.octets();
+    assert_eq!(OCTETS, [127, 0, 0, 1]);
+
+    const IS_UNSPECIFIED: bool = IP_ADDRESS.is_unspecified();
+    assert!(!IS_UNSPECIFIED);
+
+    const IS_LOOPBACK: bool = IP_ADDRESS.is_loopback();
+    assert!(IS_LOOPBACK);
+
+    const IS_PRIVATE: bool = IP_ADDRESS.is_private();
+    assert!(!IS_PRIVATE);
+
+    const IS_LINK_LOCAL: bool = IP_ADDRESS.is_link_local();
+    assert!(!IS_LINK_LOCAL);
+
+    const IS_GLOBAL: bool = IP_ADDRESS.is_global();
+    assert!(!IS_GLOBAL);
+
+    const IS_SHARED: bool = IP_ADDRESS.is_shared();
+    assert!(!IS_SHARED);
+
+    const IS_BENCHMARKING: bool = IP_ADDRESS.is_benchmarking();
+    assert!(!IS_BENCHMARKING);
+
+    const IS_RESERVED: bool = IP_ADDRESS.is_reserved();
+    assert!(!IS_RESERVED);
+
+    const IS_MULTICAST: bool = IP_ADDRESS.is_multicast();
+    assert!(!IS_MULTICAST);
+
+    const IS_BROADCAST: bool = IP_ADDRESS.is_broadcast();
+    assert!(!IS_BROADCAST);
+
+    const IS_DOCUMENTATION: bool = IP_ADDRESS.is_documentation();
+    assert!(!IS_DOCUMENTATION);
+
+    const IP_V6_COMPATIBLE: Ipv6Addr = IP_ADDRESS.to_ipv6_compatible();
+    assert_eq!(
+        IP_V6_COMPATIBLE,
+        Ipv6Addr::from([0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 127, 0, 0, 1])
+    );
+
+    const IP_V6_MAPPED: Ipv6Addr = IP_ADDRESS.to_ipv6_mapped();
+    assert_eq!(
+        IP_V6_MAPPED,
+        Ipv6Addr::from([0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 255, 255, 127, 0, 0, 1])
+    );
+}
+
+#[test]
+fn ipv6_const() {
+    // test that the methods of `Ipv6Addr` are usable in a const context
+
+    const IP_ADDRESS: Ipv6Addr = Ipv6Addr::new(0, 0, 0, 0, 0, 0, 0, 1);
+    assert_eq!(IP_ADDRESS, Ipv6Addr::LOCALHOST);
+
+    const SEGMENTS: [u16; 8] = IP_ADDRESS.segments();
+    assert_eq!(SEGMENTS, [0, 0, 0, 0, 0, 0, 0, 1]);
+
+    const OCTETS: [u8; 16] = IP_ADDRESS.octets();
+    assert_eq!(OCTETS, [0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1]);
+
+    const IS_UNSPECIFIED: bool = IP_ADDRESS.is_unspecified();
+    assert!(!IS_UNSPECIFIED);
+
+    const IS_LOOPBACK: bool = IP_ADDRESS.is_loopback();
+    assert!(IS_LOOPBACK);
+
+    const IS_GLOBAL: bool = IP_ADDRESS.is_global();
+    assert!(!IS_GLOBAL);
+
+    const IS_UNIQUE_LOCAL: bool = IP_ADDRESS.is_unique_local();
+    assert!(!IS_UNIQUE_LOCAL);
+
+    const IS_UNICAST_LINK_LOCAL: bool = IP_ADDRESS.is_unicast_link_local();
+    assert!(!IS_UNICAST_LINK_LOCAL);
+
+    const IS_DOCUMENTATION: bool = IP_ADDRESS.is_documentation();
+    assert!(!IS_DOCUMENTATION);
+
+    const IS_BENCHMARKING: bool = IP_ADDRESS.is_benchmarking();
+    assert!(!IS_BENCHMARKING);
+
+    const IS_UNICAST_GLOBAL: bool = IP_ADDRESS.is_unicast_global();
+    assert!(!IS_UNICAST_GLOBAL);
+
+    const MULTICAST_SCOPE: Option<Ipv6MulticastScope> = IP_ADDRESS.multicast_scope();
+    assert_eq!(MULTICAST_SCOPE, None);
+
+    const IS_MULTICAST: bool = IP_ADDRESS.is_multicast();
+    assert!(!IS_MULTICAST);
+
+    const IP_V4: Option<Ipv4Addr> = IP_ADDRESS.to_ipv4();
+    assert_eq!(IP_V4.unwrap(), Ipv4Addr::new(0, 0, 0, 1));
+}
+
+#[test]
+fn ip_const() {
+    // test that the methods of `IpAddr` are usable in a const context
+
+    const IP_ADDRESS: IpAddr = IpAddr::V4(Ipv4Addr::LOCALHOST);
+
+    const IS_UNSPECIFIED: bool = IP_ADDRESS.is_unspecified();
+    assert!(!IS_UNSPECIFIED);
+
+    const IS_LOOPBACK: bool = IP_ADDRESS.is_loopback();
+    assert!(IS_LOOPBACK);
+
+    const IS_GLOBAL: bool = IP_ADDRESS.is_global();
+    assert!(!IS_GLOBAL);
+
+    const IS_MULTICAST: bool = IP_ADDRESS.is_multicast();
+    assert!(!IS_MULTICAST);
+
+    const IS_IP_V4: bool = IP_ADDRESS.is_ipv4();
+    assert!(IS_IP_V4);
+
+    const IS_IP_V6: bool = IP_ADDRESS.is_ipv6();
+    assert!(!IS_IP_V6);
+}
+
+#[test]
+fn structural_match() {
+    // test that all IP types can be structurally matched upon
+
+    const IPV4: Ipv4Addr = Ipv4Addr::LOCALHOST;
+    match IPV4 {
+        Ipv4Addr::LOCALHOST => {}
+        _ => unreachable!(),
+    }
+
+    const IPV6: Ipv6Addr = Ipv6Addr::LOCALHOST;
+    match IPV6 {
+        Ipv6Addr::LOCALHOST => {}
+        _ => unreachable!(),
+    }
+
+    const IP: IpAddr = IpAddr::V4(Ipv4Addr::LOCALHOST);
+    match IP {
+        IpAddr::V4(Ipv4Addr::LOCALHOST) => {}
+        _ => unreachable!(),
+    }
+}
diff --git a/library/std/src/net/mod.rs b/library/std/src/net/mod.rs
new file mode 100644
index 000000000..e7a40bdaf
--- /dev/null
+++ b/library/std/src/net/mod.rs
@@ -0,0 +1,90 @@
+//! Networking primitives for TCP/UDP communication.
+//!
+//! This module provides networking functionality for the Transmission Control and User
+//! Datagram Protocols, as well as types for IP and socket addresses.
+//!
+//! # Organization
+//!
+//! * [`TcpListener`] and [`TcpStream`] provide functionality for communication over TCP
+//! * [`UdpSocket`] provides functionality for communication over UDP
+//! * [`IpAddr`] represents IP addresses of either IPv4 or IPv6; [`Ipv4Addr`] and
+//!   [`Ipv6Addr`] are respectively IPv4 and IPv6 addresses
+//! * [`SocketAddr`] represents socket addresses of either IPv4 or IPv6; [`SocketAddrV4`]
+//!   and [`SocketAddrV6`] are respectively IPv4 and IPv6 socket addresses
+//! * [`ToSocketAddrs`] is a trait that used for generic address resolution when interacting
+//!   with networking objects like [`TcpListener`], [`TcpStream`] or [`UdpSocket`]
+//! * Other types are return or parameter types for various methods in this module
+//!
+//! Rust disables inheritance of socket objects to child processes by default when possible.  For
+//! example, through the use of the `CLOEXEC` flag in UNIX systems or the `HANDLE_FLAG_INHERIT`
+//! flag on Windows.
+
+#![stable(feature = "rust1", since = "1.0.0")]
+
+use crate::io::{self, ErrorKind};
+
+#[stable(feature = "rust1", since = "1.0.0")]
+pub use self::addr::{SocketAddr, SocketAddrV4, SocketAddrV6, ToSocketAddrs};
+#[stable(feature = "rust1", since = "1.0.0")]
+pub use self::ip::{IpAddr, Ipv4Addr, Ipv6Addr, Ipv6MulticastScope};
+#[stable(feature = "rust1", since = "1.0.0")]
+pub use self::parser::AddrParseError;
+#[unstable(feature = "tcplistener_into_incoming", issue = "88339")]
+pub use self::tcp::IntoIncoming;
+#[stable(feature = "rust1", since = "1.0.0")]
+pub use self::tcp::{Incoming, TcpListener, TcpStream};
+#[stable(feature = "rust1", since = "1.0.0")]
+pub use self::udp::UdpSocket;
+
+mod addr;
+mod ip;
+mod parser;
+mod tcp;
+#[cfg(test)]
+mod test;
+mod udp;
+
+/// Possible values which can be passed to the [`TcpStream::shutdown`] method.
+#[derive(Copy, Clone, PartialEq, Eq, Debug)]
+#[stable(feature = "rust1", since = "1.0.0")]
+pub enum Shutdown {
+    /// The reading portion of the [`TcpStream`] should be shut down.
+    ///
+    /// All currently blocked and future [reads] will return <code>[Ok]\(0)</code>.
+    ///
+    /// [reads]: crate::io::Read "io::Read"
+    #[stable(feature = "rust1", since = "1.0.0")]
+    Read,
+    /// The writing portion of the [`TcpStream`] should be shut down.
+    ///
+    /// All currently blocked and future [writes] will return an error.
+    ///
+    /// [writes]: crate::io::Write "io::Write"
+    #[stable(feature = "rust1", since = "1.0.0")]
+    Write,
+    /// Both the reading and the writing portions of the [`TcpStream`] should be shut down.
+    ///
+    /// See [`Shutdown::Read`] and [`Shutdown::Write`] for more information.
+    #[stable(feature = "rust1", since = "1.0.0")]
+    Both,
+}
+
+fn each_addr<A: ToSocketAddrs, F, T>(addr: A, mut f: F) -> io::Result<T>
+where
+    F: FnMut(io::Result<&SocketAddr>) -> io::Result<T>,
+{
+    let addrs = match addr.to_socket_addrs() {
+        Ok(addrs) => addrs,
+        Err(e) => return f(Err(e)),
+    };
+    let mut last_err = None;
+    for addr in addrs {
+        match f(Ok(&addr)) {
+            Ok(l) => return Ok(l),
+            Err(e) => last_err = Some(e),
+        }
+    }
+    Err(last_err.unwrap_or_else(|| {
+        io::const_io_error!(ErrorKind::InvalidInput, "could not resolve to any addresses")
+    }))
+}
diff --git a/library/std/src/net/parser.rs b/library/std/src/net/parser.rs
new file mode 100644
index 000000000..069b66099
--- /dev/null
+++ b/library/std/src/net/parser.rs
@@ -0,0 +1,388 @@
+//! A private parser implementation of IPv4, IPv6, and socket addresses.
+//!
+//! This module is "publicly exported" through the `FromStr` implementations
+//! below.
+
+#[cfg(test)]
+mod tests;
+
+use crate::error::Error;
+use crate::fmt;
+use crate::net::{IpAddr, Ipv4Addr, Ipv6Addr, SocketAddr, SocketAddrV4, SocketAddrV6};
+use crate::str::FromStr;
+
+trait ReadNumberHelper: crate::marker::Sized {
+    const ZERO: Self;
+    fn checked_mul(&self, other: u32) -> Option<Self>;
+    fn checked_add(&self, other: u32) -> Option<Self>;
+}
+
+macro_rules! impl_helper {
+    ($($t:ty)*) => ($(impl ReadNumberHelper for $t {
+        const ZERO: Self = 0;
+        #[inline]
+        fn checked_mul(&self, other: u32) -> Option<Self> {
+            Self::checked_mul(*self, other.try_into().ok()?)
+        }
+        #[inline]
+        fn checked_add(&self, other: u32) -> Option<Self> {
+            Self::checked_add(*self, other.try_into().ok()?)
+        }
+    })*)
+}
+
+impl_helper! { u8 u16 u32 }
+
+struct Parser<'a> {
+    // Parsing as ASCII, so can use byte array.
+    state: &'a [u8],
+}
+
+impl<'a> Parser<'a> {
+    fn new(input: &'a str) -> Parser<'a> {
+        Parser { state: input.as_bytes() }
+    }
+
+    /// Run a parser, and restore the pre-parse state if it fails.
+    fn read_atomically<T, F>(&mut self, inner: F) -> Option<T>
+    where
+        F: FnOnce(&mut Parser<'_>) -> Option<T>,
+    {
+        let state = self.state;
+        let result = inner(self);
+        if result.is_none() {
+            self.state = state;
+        }
+        result
+    }
+
+    /// Run a parser, but fail if the entire input wasn't consumed.
+    /// Doesn't run atomically.
+    fn parse_with<T, F>(&mut self, inner: F, kind: AddrKind) -> Result<T, AddrParseError>
+    where
+        F: FnOnce(&mut Parser<'_>) -> Option<T>,
+    {
+        let result = inner(self);
+        if self.state.is_empty() { result } else { None }.ok_or(AddrParseError(kind))
+    }
+
+    /// Peek the next character from the input
+    fn peek_char(&self) -> Option<char> {
+        self.state.first().map(|&b| char::from(b))
+    }
+
+    /// Read the next character from the input
+    fn read_char(&mut self) -> Option<char> {
+        self.state.split_first().map(|(&b, tail)| {
+            self.state = tail;
+            char::from(b)
+        })
+    }
+
+    #[must_use]
+    /// Read the next character from the input if it matches the target.
+    fn read_given_char(&mut self, target: char) -> Option<()> {
+        self.read_atomically(|p| {
+            p.read_char().and_then(|c| if c == target { Some(()) } else { None })
+        })
+    }
+
+    /// Helper for reading separators in an indexed loop. Reads the separator
+    /// character iff index > 0, then runs the parser. When used in a loop,
+    /// the separator character will only be read on index > 0 (see
+    /// read_ipv4_addr for an example)
+    fn read_separator<T, F>(&mut self, sep: char, index: usize, inner: F) -> Option<T>
+    where
+        F: FnOnce(&mut Parser<'_>) -> Option<T>,
+    {
+        self.read_atomically(move |p| {
+            if index > 0 {
+                p.read_given_char(sep)?;
+            }
+            inner(p)
+        })
+    }
+
+    // Read a number off the front of the input in the given radix, stopping
+    // at the first non-digit character or eof. Fails if the number has more
+    // digits than max_digits or if there is no number.
+    fn read_number<T: ReadNumberHelper>(
+        &mut self,
+        radix: u32,
+        max_digits: Option<usize>,
+        allow_zero_prefix: bool,
+    ) -> Option<T> {
+        self.read_atomically(move |p| {
+            let mut result = T::ZERO;
+            let mut digit_count = 0;
+            let has_leading_zero = p.peek_char() == Some('0');
+
+            while let Some(digit) = p.read_atomically(|p| p.read_char()?.to_digit(radix)) {
+                result = result.checked_mul(radix)?;
+                result = result.checked_add(digit)?;
+                digit_count += 1;
+                if let Some(max_digits) = max_digits {
+                    if digit_count > max_digits {
+                        return None;
+                    }
+                }
+            }
+
+            if digit_count == 0 {
+                None
+            } else if !allow_zero_prefix && has_leading_zero && digit_count > 1 {
+                None
+            } else {
+                Some(result)
+            }
+        })
+    }
+
+    /// Read an IPv4 address.
+    fn read_ipv4_addr(&mut self) -> Option<Ipv4Addr> {
+        self.read_atomically(|p| {
+            let mut groups = [0; 4];
+
+            for (i, slot) in groups.iter_mut().enumerate() {
+                *slot = p.read_separator('.', i, |p| {
+                    // Disallow octal number in IP string.
+                    // https://tools.ietf.org/html/rfc6943#section-3.1.1
+                    p.read_number(10, Some(3), false)
+                })?;
+            }
+
+            Some(groups.into())
+        })
+    }
+
+    /// Read an IPv6 Address.
+    fn read_ipv6_addr(&mut self) -> Option<Ipv6Addr> {
+        /// Read a chunk of an IPv6 address into `groups`. Returns the number
+        /// of groups read, along with a bool indicating if an embedded
+        /// trailing IPv4 address was read. Specifically, read a series of
+        /// colon-separated IPv6 groups (0x0000 - 0xFFFF), with an optional
+        /// trailing embedded IPv4 address.
+        fn read_groups(p: &mut Parser<'_>, groups: &mut [u16]) -> (usize, bool) {
+            let limit = groups.len();
+
+            for (i, slot) in groups.iter_mut().enumerate() {
+                // Try to read a trailing embedded IPv4 address. There must be
+                // at least two groups left.
+                if i < limit - 1 {
+                    let ipv4 = p.read_separator(':', i, |p| p.read_ipv4_addr());
+
+                    if let Some(v4_addr) = ipv4 {
+                        let [one, two, three, four] = v4_addr.octets();
+                        groups[i + 0] = u16::from_be_bytes([one, two]);
+                        groups[i + 1] = u16::from_be_bytes([three, four]);
+                        return (i + 2, true);
+                    }
+                }
+
+                let group = p.read_separator(':', i, |p| p.read_number(16, Some(4), true));
+
+                match group {
+                    Some(g) => *slot = g,
+                    None => return (i, false),
+                }
+            }
+            (groups.len(), false)
+        }
+
+        self.read_atomically(|p| {
+            // Read the front part of the address; either the whole thing, or up
+            // to the first ::
+            let mut head = [0; 8];
+            let (head_size, head_ipv4) = read_groups(p, &mut head);
+
+            if head_size == 8 {
+                return Some(head.into());
+            }
+
+            // IPv4 part is not allowed before `::`
+            if head_ipv4 {
+                return None;
+            }
+
+            // Read `::` if previous code parsed less than 8 groups.
+            // `::` indicates one or more groups of 16 bits of zeros.
+            p.read_given_char(':')?;
+            p.read_given_char(':')?;
+
+            // Read the back part of the address. The :: must contain at least one
+            // set of zeroes, so our max length is 7.
+            let mut tail = [0; 7];
+            let limit = 8 - (head_size + 1);
+            let (tail_size, _) = read_groups(p, &mut tail[..limit]);
+
+            // Concat the head and tail of the IP address
+            head[(8 - tail_size)..8].copy_from_slice(&tail[..tail_size]);
+
+            Some(head.into())
+        })
+    }
+
+    /// Read an IP Address, either IPv4 or IPv6.
+    fn read_ip_addr(&mut self) -> Option<IpAddr> {
+        self.read_ipv4_addr().map(IpAddr::V4).or_else(move || self.read_ipv6_addr().map(IpAddr::V6))
+    }
+
+    /// Read a `:` followed by a port in base 10.
+    fn read_port(&mut self) -> Option<u16> {
+        self.read_atomically(|p| {
+            p.read_given_char(':')?;
+            p.read_number(10, None, true)
+        })
+    }
+
+    /// Read a `%` followed by a scope ID in base 10.
+    fn read_scope_id(&mut self) -> Option<u32> {
+        self.read_atomically(|p| {
+            p.read_given_char('%')?;
+            p.read_number(10, None, true)
+        })
+    }
+
+    /// Read an IPv4 address with a port.
+    fn read_socket_addr_v4(&mut self) -> Option<SocketAddrV4> {
+        self.read_atomically(|p| {
+            let ip = p.read_ipv4_addr()?;
+            let port = p.read_port()?;
+            Some(SocketAddrV4::new(ip, port))
+        })
+    }
+
+    /// Read an IPv6 address with a port.
+    fn read_socket_addr_v6(&mut self) -> Option<SocketAddrV6> {
+        self.read_atomically(|p| {
+            p.read_given_char('[')?;
+            let ip = p.read_ipv6_addr()?;
+            let scope_id = p.read_scope_id().unwrap_or(0);
+            p.read_given_char(']')?;
+
+            let port = p.read_port()?;
+            Some(SocketAddrV6::new(ip, port, 0, scope_id))
+        })
+    }
+
+    /// Read an IP address with a port
+    fn read_socket_addr(&mut self) -> Option<SocketAddr> {
+        self.read_socket_addr_v4()
+            .map(SocketAddr::V4)
+            .or_else(|| self.read_socket_addr_v6().map(SocketAddr::V6))
+    }
+}
+
+#[stable(feature = "ip_addr", since = "1.7.0")]
+impl FromStr for IpAddr {
+    type Err = AddrParseError;
+    fn from_str(s: &str) -> Result<IpAddr, AddrParseError> {
+        Parser::new(s).parse_with(|p| p.read_ip_addr(), AddrKind::Ip)
+    }
+}
+
+#[stable(feature = "rust1", since = "1.0.0")]
+impl FromStr for Ipv4Addr {
+    type Err = AddrParseError;
+    fn from_str(s: &str) -> Result<Ipv4Addr, AddrParseError> {
+        // don't try to parse if too long
+        if s.len() > 15 {
+            Err(AddrParseError(AddrKind::Ipv4))
+        } else {
+            Parser::new(s).parse_with(|p| p.read_ipv4_addr(), AddrKind::Ipv4)
+        }
+    }
+}
+
+#[stable(feature = "rust1", since = "1.0.0")]
+impl FromStr for Ipv6Addr {
+    type Err = AddrParseError;
+    fn from_str(s: &str) -> Result<Ipv6Addr, AddrParseError> {
+        Parser::new(s).parse_with(|p| p.read_ipv6_addr(), AddrKind::Ipv6)
+    }
+}
+
+#[stable(feature = "socket_addr_from_str", since = "1.5.0")]
+impl FromStr for SocketAddrV4 {
+    type Err = AddrParseError;
+    fn from_str(s: &str) -> Result<SocketAddrV4, AddrParseError> {
+        Parser::new(s).parse_with(|p| p.read_socket_addr_v4(), AddrKind::SocketV4)
+    }
+}
+
+#[stable(feature = "socket_addr_from_str", since = "1.5.0")]
+impl FromStr for SocketAddrV6 {
+    type Err = AddrParseError;
+    fn from_str(s: &str) -> Result<SocketAddrV6, AddrParseError> {
+        Parser::new(s).parse_with(|p| p.read_socket_addr_v6(), AddrKind::SocketV6)
+    }
+}
+
+#[stable(feature = "rust1", since = "1.0.0")]
+impl FromStr for SocketAddr {
+    type Err = AddrParseError;
+    fn from_str(s: &str) -> Result<SocketAddr, AddrParseError> {
+        Parser::new(s).parse_with(|p| p.read_socket_addr(), AddrKind::Socket)
+    }
+}
+
+#[derive(Debug, Clone, PartialEq, Eq)]
+enum AddrKind {
+    Ip,
+    Ipv4,
+    Ipv6,
+    Socket,
+    SocketV4,
+    SocketV6,
+}
+
+/// An error which can be returned when parsing an IP address or a socket address.
+///
+/// This error is used as the error type for the [`FromStr`] implementation for
+/// [`IpAddr`], [`Ipv4Addr`], [`Ipv6Addr`], [`SocketAddr`], [`SocketAddrV4`], and
+/// [`SocketAddrV6`].
+///
+/// # Potential causes
+///
+/// `AddrParseError` may be thrown because the provided string does not parse as the given type,
+/// often because it includes information only handled by a different address type.
+///
+/// ```should_panic
+/// use std::net::IpAddr;
+/// let _foo: IpAddr = "127.0.0.1:8080".parse().expect("Cannot handle the socket port");
+/// ```
+///
+/// [`IpAddr`] doesn't handle the port. Use [`SocketAddr`] instead.
+///
+/// ```
+/// use std::net::SocketAddr;
+///
+/// // No problem, the `panic!` message has disappeared.
+/// let _foo: SocketAddr = "127.0.0.1:8080".parse().expect("unreachable panic");
+/// ```
+#[stable(feature = "rust1", since = "1.0.0")]
+#[derive(Debug, Clone, PartialEq, Eq)]
+pub struct AddrParseError(AddrKind);
+
+#[stable(feature = "addr_parse_error_error", since = "1.4.0")]
+impl fmt::Display for AddrParseError {
+    #[allow(deprecated, deprecated_in_future)]
+    fn fmt(&self, fmt: &mut fmt::Formatter<'_>) -> fmt::Result {
+        fmt.write_str(self.description())
+    }
+}
+
+#[stable(feature = "addr_parse_error_error", since = "1.4.0")]
+impl Error for AddrParseError {
+    #[allow(deprecated)]
+    fn description(&self) -> &str {
+        match self.0 {
+            AddrKind::Ip => "invalid IP address syntax",
+            AddrKind::Ipv4 => "invalid IPv4 address syntax",
+            AddrKind::Ipv6 => "invalid IPv6 address syntax",
+            AddrKind::Socket => "invalid socket address syntax",
+            AddrKind::SocketV4 => "invalid IPv4 socket address syntax",
+            AddrKind::SocketV6 => "invalid IPv6 socket address syntax",
+        }
+    }
+}
diff --git a/library/std/src/net/parser/tests.rs b/library/std/src/net/parser/tests.rs
new file mode 100644
index 000000000..6d2d48eca
--- /dev/null
+++ b/library/std/src/net/parser/tests.rs
@@ -0,0 +1,149 @@
+// FIXME: These tests are all excellent candidates for AFL fuzz testing
+use crate::net::{IpAddr, Ipv4Addr, Ipv6Addr, SocketAddr, SocketAddrV4, SocketAddrV6};
+use crate::str::FromStr;
+
+const PORT: u16 = 8080;
+const SCOPE_ID: u32 = 1337;
+
+const IPV4: Ipv4Addr = Ipv4Addr::new(192, 168, 0, 1);
+const IPV4_STR: &str = "192.168.0.1";
+const IPV4_STR_PORT: &str = "192.168.0.1:8080";
+const IPV4_STR_WITH_OCTAL: &str = "0127.0.0.1";
+const IPV4_STR_WITH_HEX: &str = "0x10.0.0.1";
+
+const IPV6: Ipv6Addr = Ipv6Addr::new(0x2001, 0xdb8, 0, 0, 0, 0, 0xc0a8, 0x1);
+const IPV6_STR_FULL: &str = "2001:db8:0:0:0:0:c0a8:1";
+const IPV6_STR_COMPRESS: &str = "2001:db8::c0a8:1";
+const IPV6_STR_V4: &str = "2001:db8::192.168.0.1";
+const IPV6_STR_V4_WITH_OCTAL: &str = "2001:db8::0127.0.0.1";
+const IPV6_STR_V4_WITH_HEX: &str = "2001:db8::0x10.0.0.1";
+const IPV6_STR_PORT: &str = "[2001:db8::c0a8:1]:8080";
+const IPV6_STR_PORT_SCOPE_ID: &str = "[2001:db8::c0a8:1%1337]:8080";
+
+#[test]
+fn parse_ipv4() {
+    let result: Ipv4Addr = IPV4_STR.parse().unwrap();
+    assert_eq!(result, IPV4);
+
+    assert!(Ipv4Addr::from_str(IPV4_STR_PORT).is_err());
+    assert!(Ipv4Addr::from_str(IPV4_STR_WITH_OCTAL).is_err());
+    assert!(Ipv4Addr::from_str(IPV4_STR_WITH_HEX).is_err());
+    assert!(Ipv4Addr::from_str(IPV6_STR_FULL).is_err());
+    assert!(Ipv4Addr::from_str(IPV6_STR_COMPRESS).is_err());
+    assert!(Ipv4Addr::from_str(IPV6_STR_V4).is_err());
+    assert!(Ipv4Addr::from_str(IPV6_STR_PORT).is_err());
+}
+
+#[test]
+fn parse_ipv6() {
+    let result: Ipv6Addr = IPV6_STR_FULL.parse().unwrap();
+    assert_eq!(result, IPV6);
+
+    let result: Ipv6Addr = IPV6_STR_COMPRESS.parse().unwrap();
+    assert_eq!(result, IPV6);
+
+    let result: Ipv6Addr = IPV6_STR_V4.parse().unwrap();
+    assert_eq!(result, IPV6);
+
+    assert!(Ipv6Addr::from_str(IPV6_STR_V4_WITH_OCTAL).is_err());
+    assert!(Ipv6Addr::from_str(IPV6_STR_V4_WITH_HEX).is_err());
+    assert!(Ipv6Addr::from_str(IPV4_STR).is_err());
+    assert!(Ipv6Addr::from_str(IPV4_STR_PORT).is_err());
+    assert!(Ipv6Addr::from_str(IPV6_STR_PORT).is_err());
+}
+
+#[test]
+fn parse_ip() {
+    let result: IpAddr = IPV4_STR.parse().unwrap();
+    assert_eq!(result, IpAddr::from(IPV4));
+
+    let result: IpAddr = IPV6_STR_FULL.parse().unwrap();
+    assert_eq!(result, IpAddr::from(IPV6));
+
+    let result: IpAddr = IPV6_STR_COMPRESS.parse().unwrap();
+    assert_eq!(result, IpAddr::from(IPV6));
+
+    let result: IpAddr = IPV6_STR_V4.parse().unwrap();
+    assert_eq!(result, IpAddr::from(IPV6));
+
+    assert!(IpAddr::from_str(IPV4_STR_PORT).is_err());
+    assert!(IpAddr::from_str(IPV6_STR_PORT).is_err());
+}
+
+#[test]
+fn parse_socket_v4() {
+    let result: SocketAddrV4 = IPV4_STR_PORT.parse().unwrap();
+    assert_eq!(result, SocketAddrV4::new(IPV4, PORT));
+
+    assert!(SocketAddrV4::from_str(IPV4_STR).is_err());
+    assert!(SocketAddrV4::from_str(IPV6_STR_FULL).is_err());
+    assert!(SocketAddrV4::from_str(IPV6_STR_COMPRESS).is_err());
+    assert!(SocketAddrV4::from_str(IPV6_STR_V4).is_err());
+    assert!(SocketAddrV4::from_str(IPV6_STR_PORT).is_err());
+}
+
+#[test]
+fn parse_socket_v6() {
+    assert_eq!(IPV6_STR_PORT.parse(), Ok(SocketAddrV6::new(IPV6, PORT, 0, 0)));
+    assert_eq!(IPV6_STR_PORT_SCOPE_ID.parse(), Ok(SocketAddrV6::new(IPV6, PORT, 0, SCOPE_ID)));
+
+    assert!(SocketAddrV6::from_str(IPV4_STR).is_err());
+    assert!(SocketAddrV6::from_str(IPV4_STR_PORT).is_err());
+    assert!(SocketAddrV6::from_str(IPV6_STR_FULL).is_err());
+    assert!(SocketAddrV6::from_str(IPV6_STR_COMPRESS).is_err());
+    assert!(SocketAddrV6::from_str(IPV6_STR_V4).is_err());
+}
+
+#[test]
+fn parse_socket() {
+    let result: SocketAddr = IPV4_STR_PORT.parse().unwrap();
+    assert_eq!(result, SocketAddr::from((IPV4, PORT)));
+
+    let result: SocketAddr = IPV6_STR_PORT.parse().unwrap();
+    assert_eq!(result, SocketAddr::from((IPV6, PORT)));
+
+    assert!(SocketAddr::from_str(IPV4_STR).is_err());
+    assert!(SocketAddr::from_str(IPV6_STR_FULL).is_err());
+    assert!(SocketAddr::from_str(IPV6_STR_COMPRESS).is_err());
+    assert!(SocketAddr::from_str(IPV6_STR_V4).is_err());
+}
+
+#[test]
+fn ipv6_corner_cases() {
+    let result: Ipv6Addr = "1::".parse().unwrap();
+    assert_eq!(result, Ipv6Addr::new(1, 0, 0, 0, 0, 0, 0, 0));
+
+    let result: Ipv6Addr = "1:1::".parse().unwrap();
+    assert_eq!(result, Ipv6Addr::new(1, 1, 0, 0, 0, 0, 0, 0));
+
+    let result: Ipv6Addr = "::1".parse().unwrap();
+    assert_eq!(result, Ipv6Addr::new(0, 0, 0, 0, 0, 0, 0, 1));
+
+    let result: Ipv6Addr = "::1:1".parse().unwrap();
+    assert_eq!(result, Ipv6Addr::new(0, 0, 0, 0, 0, 0, 1, 1));
+
+    let result: Ipv6Addr = "::".parse().unwrap();
+    assert_eq!(result, Ipv6Addr::new(0, 0, 0, 0, 0, 0, 0, 0));
+
+    let result: Ipv6Addr = "::192.168.0.1".parse().unwrap();
+    assert_eq!(result, Ipv6Addr::new(0, 0, 0, 0, 0, 0, 0xc0a8, 0x1));
+
+    let result: Ipv6Addr = "::1:192.168.0.1".parse().unwrap();
+    assert_eq!(result, Ipv6Addr::new(0, 0, 0, 0, 0, 1, 0xc0a8, 0x1));
+
+    let result: Ipv6Addr = "1:1:1:1:1:1:192.168.0.1".parse().unwrap();
+    assert_eq!(result, Ipv6Addr::new(1, 1, 1, 1, 1, 1, 0xc0a8, 0x1));
+}
+
+// Things that might not seem like failures but are
+#[test]
+fn ipv6_corner_failures() {
+    // No IP address before the ::
+    assert!(Ipv6Addr::from_str("1:192.168.0.1::").is_err());
+
+    // :: must have at least 1 set of zeroes
+    assert!(Ipv6Addr::from_str("1:1:1:1::1:1:1:1").is_err());
+
+    // Need brackets for a port
+    assert!(SocketAddrV6::from_str("1:1:1:1:1:1:1:1:8080").is_err());
+}
diff --git a/library/std/src/net/tcp.rs b/library/std/src/net/tcp.rs
new file mode 100644
index 000000000..69b72a81c
--- /dev/null
+++ b/library/std/src/net/tcp.rs
@@ -0,0 +1,1050 @@
+#![deny(unsafe_op_in_unsafe_fn)]
+
+#[cfg(all(test, not(target_os = "emscripten")))]
+mod tests;
+
+use crate::io::prelude::*;
+
+use crate::fmt;
+use crate::io::{self, IoSlice, IoSliceMut};
+use crate::iter::FusedIterator;
+use crate::net::{Shutdown, SocketAddr, ToSocketAddrs};
+use crate::sys_common::net as net_imp;
+use crate::sys_common::{AsInner, FromInner, IntoInner};
+use crate::time::Duration;
+
+/// A TCP stream between a local and a remote socket.
+///
+/// After creating a `TcpStream` by either [`connect`]ing to a remote host or
+/// [`accept`]ing a connection on a [`TcpListener`], data can be transmitted
+/// by [reading] and [writing] to it.
+///
+/// The connection will be closed when the value is dropped. The reading and writing
+/// portions of the connection can also be shut down individually with the [`shutdown`]
+/// method.
+///
+/// The Transmission Control Protocol is specified in [IETF RFC 793].
+///
+/// [`accept`]: TcpListener::accept
+/// [`connect`]: TcpStream::connect
+/// [IETF RFC 793]: https://tools.ietf.org/html/rfc793
+/// [reading]: Read
+/// [`shutdown`]: TcpStream::shutdown
+/// [writing]: Write
+///
+/// # Examples
+///
+/// ```no_run
+/// use std::io::prelude::*;
+/// use std::net::TcpStream;
+///
+/// fn main() -> std::io::Result<()> {
+///     let mut stream = TcpStream::connect("127.0.0.1:34254")?;
+///
+///     stream.write(&[1])?;
+///     stream.read(&mut [0; 128])?;
+///     Ok(())
+/// } // the stream is closed here
+/// ```
+#[stable(feature = "rust1", since = "1.0.0")]
+pub struct TcpStream(net_imp::TcpStream);
+
+/// A TCP socket server, listening for connections.
+///
+/// After creating a `TcpListener` by [`bind`]ing it to a socket address, it listens
+/// for incoming TCP connections. These can be accepted by calling [`accept`] or by
+/// iterating over the [`Incoming`] iterator returned by [`incoming`][`TcpListener::incoming`].
+///
+/// The socket will be closed when the value is dropped.
+///
+/// The Transmission Control Protocol is specified in [IETF RFC 793].
+///
+/// [`accept`]: TcpListener::accept
+/// [`bind`]: TcpListener::bind
+/// [IETF RFC 793]: https://tools.ietf.org/html/rfc793
+///
+/// # Examples
+///
+/// ```no_run
+/// use std::net::{TcpListener, TcpStream};
+///
+/// fn handle_client(stream: TcpStream) {
+///     // ...
+/// }
+///
+/// fn main() -> std::io::Result<()> {
+///     let listener = TcpListener::bind("127.0.0.1:80")?;
+///
+///     // accept connections and process them serially
+///     for stream in listener.incoming() {
+///         handle_client(stream?);
+///     }
+///     Ok(())
+/// }
+/// ```
+#[stable(feature = "rust1", since = "1.0.0")]
+pub struct TcpListener(net_imp::TcpListener);
+
+/// An iterator that infinitely [`accept`]s connections on a [`TcpListener`].
+///
+/// This `struct` is created by the [`TcpListener::incoming`] method.
+/// See its documentation for more.
+///
+/// [`accept`]: TcpListener::accept
+#[must_use = "iterators are lazy and do nothing unless consumed"]
+#[stable(feature = "rust1", since = "1.0.0")]
+#[derive(Debug)]
+pub struct Incoming<'a> {
+    listener: &'a TcpListener,
+}
+
+/// An iterator that infinitely [`accept`]s connections on a [`TcpListener`].
+///
+/// This `struct` is created by the [`TcpListener::into_incoming`] method.
+/// See its documentation for more.
+///
+/// [`accept`]: TcpListener::accept
+#[derive(Debug)]
+#[unstable(feature = "tcplistener_into_incoming", issue = "88339")]
+pub struct IntoIncoming {
+    listener: TcpListener,
+}
+
+impl TcpStream {
+    /// Opens a TCP connection to a remote host.
+    ///
+    /// `addr` is an address of the remote host. Anything which implements
+    /// [`ToSocketAddrs`] trait can be supplied for the address; see this trait
+    /// documentation for concrete examples.
+    ///
+    /// If `addr` yields multiple addresses, `connect` will be attempted with
+    /// each of the addresses until a connection is successful. If none of
+    /// the addresses result in a successful connection, the error returned from
+    /// the last connection attempt (the last address) is returned.
+    ///
+    /// # Examples
+    ///
+    /// Open a TCP connection to `127.0.0.1:8080`:
+    ///
+    /// ```no_run
+    /// use std::net::TcpStream;
+    ///
+    /// if let Ok(stream) = TcpStream::connect("127.0.0.1:8080") {
+    ///     println!("Connected to the server!");
+    /// } else {
+    ///     println!("Couldn't connect to server...");
+    /// }
+    /// ```
+    ///
+    /// Open a TCP connection to `127.0.0.1:8080`. If the connection fails, open
+    /// a TCP connection to `127.0.0.1:8081`:
+    ///
+    /// ```no_run
+    /// use std::net::{SocketAddr, TcpStream};
+    ///
+    /// let addrs = [
+    ///     SocketAddr::from(([127, 0, 0, 1], 8080)),
+    ///     SocketAddr::from(([127, 0, 0, 1], 8081)),
+    /// ];
+    /// if let Ok(stream) = TcpStream::connect(&addrs[..]) {
+    ///     println!("Connected to the server!");
+    /// } else {
+    ///     println!("Couldn't connect to server...");
+    /// }
+    /// ```
+    #[stable(feature = "rust1", since = "1.0.0")]
+    pub fn connect<A: ToSocketAddrs>(addr: A) -> io::Result<TcpStream> {
+        super::each_addr(addr, net_imp::TcpStream::connect).map(TcpStream)
+    }
+
+    /// Opens a TCP connection to a remote host with a timeout.
+    ///
+    /// Unlike `connect`, `connect_timeout` takes a single [`SocketAddr`] since
+    /// timeout must be applied to individual addresses.
+    ///
+    /// It is an error to pass a zero `Duration` to this function.
+    ///
+    /// Unlike other methods on `TcpStream`, this does not correspond to a
+    /// single system call. It instead calls `connect` in nonblocking mode and
+    /// then uses an OS-specific mechanism to await the completion of the
+    /// connection request.
+    #[stable(feature = "tcpstream_connect_timeout", since = "1.21.0")]
+    pub fn connect_timeout(addr: &SocketAddr, timeout: Duration) -> io::Result<TcpStream> {
+        net_imp::TcpStream::connect_timeout(addr, timeout).map(TcpStream)
+    }
+
+    /// Returns the socket address of the remote peer of this TCP connection.
+    ///
+    /// # Examples
+    ///
+    /// ```no_run
+    /// use std::net::{Ipv4Addr, SocketAddr, SocketAddrV4, TcpStream};
+    ///
+    /// let stream = TcpStream::connect("127.0.0.1:8080")
+    ///                        .expect("Couldn't connect to the server...");
+    /// assert_eq!(stream.peer_addr().unwrap(),
+    ///            SocketAddr::V4(SocketAddrV4::new(Ipv4Addr::new(127, 0, 0, 1), 8080)));
+    /// ```
+    #[stable(feature = "rust1", since = "1.0.0")]
+    pub fn peer_addr(&self) -> io::Result<SocketAddr> {
+        self.0.peer_addr()
+    }
+
+    /// Returns the socket address of the local half of this TCP connection.
+    ///
+    /// # Examples
+    ///
+    /// ```no_run
+    /// use std::net::{IpAddr, Ipv4Addr, TcpStream};
+    ///
+    /// let stream = TcpStream::connect("127.0.0.1:8080")
+    ///                        .expect("Couldn't connect to the server...");
+    /// assert_eq!(stream.local_addr().unwrap().ip(),
+    ///            IpAddr::V4(Ipv4Addr::new(127, 0, 0, 1)));
+    /// ```
+    #[stable(feature = "rust1", since = "1.0.0")]
+    pub fn local_addr(&self) -> io::Result<SocketAddr> {
+        self.0.socket_addr()
+    }
+
+    /// Shuts down the read, write, or both halves of this connection.
+    ///
+    /// This function will cause all pending and future I/O on the specified
+    /// portions to return immediately with an appropriate value (see the
+    /// documentation of [`Shutdown`]).
+    ///
+    /// # Platform-specific behavior
+    ///
+    /// Calling this function multiple times may result in different behavior,
+    /// depending on the operating system. On Linux, the second call will
+    /// return `Ok(())`, but on macOS, it will return `ErrorKind::NotConnected`.
+    /// This may change in the future.
+    ///
+    /// # Examples
+    ///
+    /// ```no_run
+    /// use std::net::{Shutdown, TcpStream};
+    ///
+    /// let stream = TcpStream::connect("127.0.0.1:8080")
+    ///                        .expect("Couldn't connect to the server...");
+    /// stream.shutdown(Shutdown::Both).expect("shutdown call failed");
+    /// ```
+    #[stable(feature = "rust1", since = "1.0.0")]
+    pub fn shutdown(&self, how: Shutdown) -> io::Result<()> {
+        self.0.shutdown(how)
+    }
+
+    /// Creates a new independently owned handle to the underlying socket.
+    ///
+    /// The returned `TcpStream` is a reference to the same stream that this
+    /// object references. Both handles will read and write the same stream of
+    /// data, and options set on one stream will be propagated to the other
+    /// stream.
+    ///
+    /// # Examples
+    ///
+    /// ```no_run
+    /// use std::net::TcpStream;
+    ///
+    /// let stream = TcpStream::connect("127.0.0.1:8080")
+    ///                        .expect("Couldn't connect to the server...");
+    /// let stream_clone = stream.try_clone().expect("clone failed...");
+    /// ```
+    #[stable(feature = "rust1", since = "1.0.0")]
+    pub fn try_clone(&self) -> io::Result<TcpStream> {
+        self.0.duplicate().map(TcpStream)
+    }
+
+    /// Sets the read timeout to the timeout specified.
+    ///
+    /// If the value specified is [`None`], then [`read`] calls will block
+    /// indefinitely. An [`Err`] is returned if the zero [`Duration`] is
+    /// passed to this method.
+    ///
+    /// # Platform-specific behavior
+    ///
+    /// Platforms may return a different error code whenever a read times out as
+    /// a result of setting this option. For example Unix typically returns an
+    /// error of the kind [`WouldBlock`], but Windows may return [`TimedOut`].
+    ///
+    /// [`read`]: Read::read
+    /// [`WouldBlock`]: io::ErrorKind::WouldBlock
+    /// [`TimedOut`]: io::ErrorKind::TimedOut
+    ///
+    /// # Examples
+    ///
+    /// ```no_run
+    /// use std::net::TcpStream;
+    ///
+    /// let stream = TcpStream::connect("127.0.0.1:8080")
+    ///                        .expect("Couldn't connect to the server...");
+    /// stream.set_read_timeout(None).expect("set_read_timeout call failed");
+    /// ```
+    ///
+    /// An [`Err`] is returned if the zero [`Duration`] is passed to this
+    /// method:
+    ///
+    /// ```no_run
+    /// use std::io;
+    /// use std::net::TcpStream;
+    /// use std::time::Duration;
+    ///
+    /// let stream = TcpStream::connect("127.0.0.1:8080").unwrap();
+    /// let result = stream.set_read_timeout(Some(Duration::new(0, 0)));
+    /// let err = result.unwrap_err();
+    /// assert_eq!(err.kind(), io::ErrorKind::InvalidInput)
+    /// ```
+    #[stable(feature = "socket_timeout", since = "1.4.0")]
+    pub fn set_read_timeout(&self, dur: Option<Duration>) -> io::Result<()> {
+        self.0.set_read_timeout(dur)
+    }
+
+    /// Sets the write timeout to the timeout specified.
+    ///
+    /// If the value specified is [`None`], then [`write`] calls will block
+    /// indefinitely. An [`Err`] is returned if the zero [`Duration`] is
+    /// passed to this method.
+    ///
+    /// # Platform-specific behavior
+    ///
+    /// Platforms may return a different error code whenever a write times out
+    /// as a result of setting this option. For example Unix typically returns
+    /// an error of the kind [`WouldBlock`], but Windows may return [`TimedOut`].
+    ///
+    /// [`write`]: Write::write
+    /// [`WouldBlock`]: io::ErrorKind::WouldBlock
+    /// [`TimedOut`]: io::ErrorKind::TimedOut
+    ///
+    /// # Examples
+    ///
+    /// ```no_run
+    /// use std::net::TcpStream;
+    ///
+    /// let stream = TcpStream::connect("127.0.0.1:8080")
+    ///                        .expect("Couldn't connect to the server...");
+    /// stream.set_write_timeout(None).expect("set_write_timeout call failed");
+    /// ```
+    ///
+    /// An [`Err`] is returned if the zero [`Duration`] is passed to this
+    /// method:
+    ///
+    /// ```no_run
+    /// use std::io;
+    /// use std::net::TcpStream;
+    /// use std::time::Duration;
+    ///
+    /// let stream = TcpStream::connect("127.0.0.1:8080").unwrap();
+    /// let result = stream.set_write_timeout(Some(Duration::new(0, 0)));
+    /// let err = result.unwrap_err();
+    /// assert_eq!(err.kind(), io::ErrorKind::InvalidInput)
+    /// ```
+    #[stable(feature = "socket_timeout", since = "1.4.0")]
+    pub fn set_write_timeout(&self, dur: Option<Duration>) -> io::Result<()> {
+        self.0.set_write_timeout(dur)
+    }
+
+    /// Returns the read timeout of this socket.
+    ///
+    /// If the timeout is [`None`], then [`read`] calls will block indefinitely.
+    ///
+    /// # Platform-specific behavior
+    ///
+    /// Some platforms do not provide access to the current timeout.
+    ///
+    /// [`read`]: Read::read
+    ///
+    /// # Examples
+    ///
+    /// ```no_run
+    /// use std::net::TcpStream;
+    ///
+    /// let stream = TcpStream::connect("127.0.0.1:8080")
+    ///                        .expect("Couldn't connect to the server...");
+    /// stream.set_read_timeout(None).expect("set_read_timeout call failed");
+    /// assert_eq!(stream.read_timeout().unwrap(), None);
+    /// ```
+    #[stable(feature = "socket_timeout", since = "1.4.0")]
+    pub fn read_timeout(&self) -> io::Result<Option<Duration>> {
+        self.0.read_timeout()
+    }
+
+    /// Returns the write timeout of this socket.
+    ///
+    /// If the timeout is [`None`], then [`write`] calls will block indefinitely.
+    ///
+    /// # Platform-specific behavior
+    ///
+    /// Some platforms do not provide access to the current timeout.
+    ///
+    /// [`write`]: Write::write
+    ///
+    /// # Examples
+    ///
+    /// ```no_run
+    /// use std::net::TcpStream;
+    ///
+    /// let stream = TcpStream::connect("127.0.0.1:8080")
+    ///                        .expect("Couldn't connect to the server...");
+    /// stream.set_write_timeout(None).expect("set_write_timeout call failed");
+    /// assert_eq!(stream.write_timeout().unwrap(), None);
+    /// ```
+    #[stable(feature = "socket_timeout", since = "1.4.0")]
+    pub fn write_timeout(&self) -> io::Result<Option<Duration>> {
+        self.0.write_timeout()
+    }
+
+    /// Receives data on the socket from the remote address to which it is
+    /// connected, without removing that data from the queue. On success,
+    /// returns the number of bytes peeked.
+    ///
+    /// Successive calls return the same data. This is accomplished by passing
+    /// `MSG_PEEK` as a flag to the underlying `recv` system call.
+    ///
+    /// # Examples
+    ///
+    /// ```no_run
+    /// use std::net::TcpStream;
+    ///
+    /// let stream = TcpStream::connect("127.0.0.1:8000")
+    ///                        .expect("Couldn't connect to the server...");
+    /// let mut buf = [0; 10];
+    /// let len = stream.peek(&mut buf).expect("peek failed");
+    /// ```
+    #[stable(feature = "peek", since = "1.18.0")]
+    pub fn peek(&self, buf: &mut [u8]) -> io::Result<usize> {
+        self.0.peek(buf)
+    }
+
+    /// Sets the value of the `SO_LINGER` option on this socket.
+    ///
+    /// This value controls how the socket is closed when data remains
+    /// to be sent. If `SO_LINGER` is set, the socket will remain open
+    /// for the specified duration as the system attempts to send pending data.
+    /// Otherwise, the system may close the socket immediately, or wait for a
+    /// default timeout.
+    ///
+    /// # Examples
+    ///
+    /// ```no_run
+    /// #![feature(tcp_linger)]
+    ///
+    /// use std::net::TcpStream;
+    /// use std::time::Duration;
+    ///
+    /// let stream = TcpStream::connect("127.0.0.1:8080")
+    ///                        .expect("Couldn't connect to the server...");
+    /// stream.set_linger(Some(Duration::from_secs(0))).expect("set_linger call failed");
+    /// ```
+    #[unstable(feature = "tcp_linger", issue = "88494")]
+    pub fn set_linger(&self, linger: Option<Duration>) -> io::Result<()> {
+        self.0.set_linger(linger)
+    }
+
+    /// Gets the value of the `SO_LINGER` option on this socket.
+    ///
+    /// For more information about this option, see [`TcpStream::set_linger`].
+    ///
+    /// # Examples
+    ///
+    /// ```no_run
+    /// #![feature(tcp_linger)]
+    ///
+    /// use std::net::TcpStream;
+    /// use std::time::Duration;
+    ///
+    /// let stream = TcpStream::connect("127.0.0.1:8080")
+    ///                        .expect("Couldn't connect to the server...");
+    /// stream.set_linger(Some(Duration::from_secs(0))).expect("set_linger call failed");
+    /// assert_eq!(stream.linger().unwrap(), Some(Duration::from_secs(0)));
+    /// ```
+    #[unstable(feature = "tcp_linger", issue = "88494")]
+    pub fn linger(&self) -> io::Result<Option<Duration>> {
+        self.0.linger()
+    }
+
+    /// Sets the value of the `TCP_NODELAY` option on this socket.
+    ///
+    /// If set, this option disables the Nagle algorithm. This means that
+    /// segments are always sent as soon as possible, even if there is only a
+    /// small amount of data. When not set, data is buffered until there is a
+    /// sufficient amount to send out, thereby avoiding the frequent sending of
+    /// small packets.
+    ///
+    /// # Examples
+    ///
+    /// ```no_run
+    /// use std::net::TcpStream;
+    ///
+    /// let stream = TcpStream::connect("127.0.0.1:8080")
+    ///                        .expect("Couldn't connect to the server...");
+    /// stream.set_nodelay(true).expect("set_nodelay call failed");
+    /// ```
+    #[stable(feature = "net2_mutators", since = "1.9.0")]
+    pub fn set_nodelay(&self, nodelay: bool) -> io::Result<()> {
+        self.0.set_nodelay(nodelay)
+    }
+
+    /// Gets the value of the `TCP_NODELAY` option on this socket.
+    ///
+    /// For more information about this option, see [`TcpStream::set_nodelay`].
+    ///
+    /// # Examples
+    ///
+    /// ```no_run
+    /// use std::net::TcpStream;
+    ///
+    /// let stream = TcpStream::connect("127.0.0.1:8080")
+    ///                        .expect("Couldn't connect to the server...");
+    /// stream.set_nodelay(true).expect("set_nodelay call failed");
+    /// assert_eq!(stream.nodelay().unwrap_or(false), true);
+    /// ```
+    #[stable(feature = "net2_mutators", since = "1.9.0")]
+    pub fn nodelay(&self) -> io::Result<bool> {
+        self.0.nodelay()
+    }
+
+    /// Sets the value for the `IP_TTL` option on this socket.
+    ///
+    /// This value sets the time-to-live field that is used in every packet sent
+    /// from this socket.
+    ///
+    /// # Examples
+    ///
+    /// ```no_run
+    /// use std::net::TcpStream;
+    ///
+    /// let stream = TcpStream::connect("127.0.0.1:8080")
+    ///                        .expect("Couldn't connect to the server...");
+    /// stream.set_ttl(100).expect("set_ttl call failed");
+    /// ```
+    #[stable(feature = "net2_mutators", since = "1.9.0")]
+    pub fn set_ttl(&self, ttl: u32) -> io::Result<()> {
+        self.0.set_ttl(ttl)
+    }
+
+    /// Gets the value of the `IP_TTL` option for this socket.
+    ///
+    /// For more information about this option, see [`TcpStream::set_ttl`].
+    ///
+    /// # Examples
+    ///
+    /// ```no_run
+    /// use std::net::TcpStream;
+    ///
+    /// let stream = TcpStream::connect("127.0.0.1:8080")
+    ///                        .expect("Couldn't connect to the server...");
+    /// stream.set_ttl(100).expect("set_ttl call failed");
+    /// assert_eq!(stream.ttl().unwrap_or(0), 100);
+    /// ```
+    #[stable(feature = "net2_mutators", since = "1.9.0")]
+    pub fn ttl(&self) -> io::Result<u32> {
+        self.0.ttl()
+    }
+
+    /// Gets the value of the `SO_ERROR` option on this socket.
+    ///
+    /// This will retrieve the stored error in the underlying socket, clearing
+    /// the field in the process. This can be useful for checking errors between
+    /// calls.
+    ///
+    /// # Examples
+    ///
+    /// ```no_run
+    /// use std::net::TcpStream;
+    ///
+    /// let stream = TcpStream::connect("127.0.0.1:8080")
+    ///                        .expect("Couldn't connect to the server...");
+    /// stream.take_error().expect("No error was expected...");
+    /// ```
+    #[stable(feature = "net2_mutators", since = "1.9.0")]
+    pub fn take_error(&self) -> io::Result<Option<io::Error>> {
+        self.0.take_error()
+    }
+
+    /// Moves this TCP stream into or out of nonblocking mode.
+    ///
+    /// This will result in `read`, `write`, `recv` and `send` operations
+    /// becoming nonblocking, i.e., immediately returning from their calls.
+    /// If the IO operation is successful, `Ok` is returned and no further
+    /// action is required. If the IO operation could not be completed and needs
+    /// to be retried, an error with kind [`io::ErrorKind::WouldBlock`] is
+    /// returned.
+    ///
+    /// On Unix platforms, calling this method corresponds to calling `fcntl`
+    /// `FIONBIO`. On Windows calling this method corresponds to calling
+    /// `ioctlsocket` `FIONBIO`.
+    ///
+    /// # Examples
+    ///
+    /// Reading bytes from a TCP stream in non-blocking mode:
+    ///
+    /// ```no_run
+    /// use std::io::{self, Read};
+    /// use std::net::TcpStream;
+    ///
+    /// let mut stream = TcpStream::connect("127.0.0.1:7878")
+    ///     .expect("Couldn't connect to the server...");
+    /// stream.set_nonblocking(true).expect("set_nonblocking call failed");
+    ///
+    /// # fn wait_for_fd() { unimplemented!() }
+    /// let mut buf = vec![];
+    /// loop {
+    ///     match stream.read_to_end(&mut buf) {
+    ///         Ok(_) => break,
+    ///         Err(ref e) if e.kind() == io::ErrorKind::WouldBlock => {
+    ///             // wait until network socket is ready, typically implemented
+    ///             // via platform-specific APIs such as epoll or IOCP
+    ///             wait_for_fd();
+    ///         }
+    ///         Err(e) => panic!("encountered IO error: {e}"),
+    ///     };
+    /// };
+    /// println!("bytes: {buf:?}");
+    /// ```
+    #[stable(feature = "net2_mutators", since = "1.9.0")]
+    pub fn set_nonblocking(&self, nonblocking: bool) -> io::Result<()> {
+        self.0.set_nonblocking(nonblocking)
+    }
+}
+
+// In addition to the `impl`s here, `TcpStream` also has `impl`s for
+// `AsFd`/`From<OwnedFd>`/`Into<OwnedFd>` and
+// `AsRawFd`/`IntoRawFd`/`FromRawFd`, on Unix and WASI, and
+// `AsSocket`/`From<OwnedSocket>`/`Into<OwnedSocket>` and
+// `AsRawSocket`/`IntoRawSocket`/`FromRawSocket` on Windows.
+
+#[stable(feature = "rust1", since = "1.0.0")]
+impl Read for TcpStream {
+    fn read(&mut self, buf: &mut [u8]) -> io::Result<usize> {
+        self.0.read(buf)
+    }
+
+    fn read_vectored(&mut self, bufs: &mut [IoSliceMut<'_>]) -> io::Result<usize> {
+        self.0.read_vectored(bufs)
+    }
+
+    #[inline]
+    fn is_read_vectored(&self) -> bool {
+        self.0.is_read_vectored()
+    }
+}
+#[stable(feature = "rust1", since = "1.0.0")]
+impl Write for TcpStream {
+    fn write(&mut self, buf: &[u8]) -> io::Result<usize> {
+        self.0.write(buf)
+    }
+
+    fn write_vectored(&mut self, bufs: &[IoSlice<'_>]) -> io::Result<usize> {
+        self.0.write_vectored(bufs)
+    }
+
+    #[inline]
+    fn is_write_vectored(&self) -> bool {
+        self.0.is_write_vectored()
+    }
+
+    fn flush(&mut self) -> io::Result<()> {
+        Ok(())
+    }
+}
+#[stable(feature = "rust1", since = "1.0.0")]
+impl Read for &TcpStream {
+    fn read(&mut self, buf: &mut [u8]) -> io::Result<usize> {
+        self.0.read(buf)
+    }
+
+    fn read_vectored(&mut self, bufs: &mut [IoSliceMut<'_>]) -> io::Result<usize> {
+        self.0.read_vectored(bufs)
+    }
+
+    #[inline]
+    fn is_read_vectored(&self) -> bool {
+        self.0.is_read_vectored()
+    }
+}
+#[stable(feature = "rust1", since = "1.0.0")]
+impl Write for &TcpStream {
+    fn write(&mut self, buf: &[u8]) -> io::Result<usize> {
+        self.0.write(buf)
+    }
+
+    fn write_vectored(&mut self, bufs: &[IoSlice<'_>]) -> io::Result<usize> {
+        self.0.write_vectored(bufs)
+    }
+
+    #[inline]
+    fn is_write_vectored(&self) -> bool {
+        self.0.is_write_vectored()
+    }
+
+    fn flush(&mut self) -> io::Result<()> {
+        Ok(())
+    }
+}
+
+impl AsInner<net_imp::TcpStream> for TcpStream {
+    fn as_inner(&self) -> &net_imp::TcpStream {
+        &self.0
+    }
+}
+
+impl FromInner<net_imp::TcpStream> for TcpStream {
+    fn from_inner(inner: net_imp::TcpStream) -> TcpStream {
+        TcpStream(inner)
+    }
+}
+
+impl IntoInner<net_imp::TcpStream> for TcpStream {
+    fn into_inner(self) -> net_imp::TcpStream {
+        self.0
+    }
+}
+
+#[stable(feature = "rust1", since = "1.0.0")]
+impl fmt::Debug for TcpStream {
+    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
+        self.0.fmt(f)
+    }
+}
+
+impl TcpListener {
+    /// Creates a new `TcpListener` which will be bound to the specified
+    /// address.
+    ///
+    /// The returned listener is ready for accepting connections.
+    ///
+    /// Binding with a port number of 0 will request that the OS assigns a port
+    /// to this listener. The port allocated can be queried via the
+    /// [`TcpListener::local_addr`] method.
+    ///
+    /// The address type can be any implementor of [`ToSocketAddrs`] trait. See
+    /// its documentation for concrete examples.
+    ///
+    /// If `addr` yields multiple addresses, `bind` will be attempted with
+    /// each of the addresses until one succeeds and returns the listener. If
+    /// none of the addresses succeed in creating a listener, the error returned
+    /// from the last attempt (the last address) is returned.
+    ///
+    /// # Examples
+    ///
+    /// Creates a TCP listener bound to `127.0.0.1:80`:
+    ///
+    /// ```no_run
+    /// use std::net::TcpListener;
+    ///
+    /// let listener = TcpListener::bind("127.0.0.1:80").unwrap();
+    /// ```
+    ///
+    /// Creates a TCP listener bound to `127.0.0.1:80`. If that fails, create a
+    /// TCP listener bound to `127.0.0.1:443`:
+    ///
+    /// ```no_run
+    /// use std::net::{SocketAddr, TcpListener};
+    ///
+    /// let addrs = [
+    ///     SocketAddr::from(([127, 0, 0, 1], 80)),
+    ///     SocketAddr::from(([127, 0, 0, 1], 443)),
+    /// ];
+    /// let listener = TcpListener::bind(&addrs[..]).unwrap();
+    /// ```
+    #[stable(feature = "rust1", since = "1.0.0")]
+    pub fn bind<A: ToSocketAddrs>(addr: A) -> io::Result<TcpListener> {
+        super::each_addr(addr, net_imp::TcpListener::bind).map(TcpListener)
+    }
+
+    /// Returns the local socket address of this listener.
+    ///
+    /// # Examples
+    ///
+    /// ```no_run
+    /// use std::net::{Ipv4Addr, SocketAddr, SocketAddrV4, TcpListener};
+    ///
+    /// let listener = TcpListener::bind("127.0.0.1:8080").unwrap();
+    /// assert_eq!(listener.local_addr().unwrap(),
+    ///            SocketAddr::V4(SocketAddrV4::new(Ipv4Addr::new(127, 0, 0, 1), 8080)));
+    /// ```
+    #[stable(feature = "rust1", since = "1.0.0")]
+    pub fn local_addr(&self) -> io::Result<SocketAddr> {
+        self.0.socket_addr()
+    }
+
+    /// Creates a new independently owned handle to the underlying socket.
+    ///
+    /// The returned [`TcpListener`] is a reference to the same socket that this
+    /// object references. Both handles can be used to accept incoming
+    /// connections and options set on one listener will affect the other.
+    ///
+    /// # Examples
+    ///
+    /// ```no_run
+    /// use std::net::TcpListener;
+    ///
+    /// let listener = TcpListener::bind("127.0.0.1:8080").unwrap();
+    /// let listener_clone = listener.try_clone().unwrap();
+    /// ```
+    #[stable(feature = "rust1", since = "1.0.0")]
+    pub fn try_clone(&self) -> io::Result<TcpListener> {
+        self.0.duplicate().map(TcpListener)
+    }
+
+    /// Accept a new incoming connection from this listener.
+    ///
+    /// This function will block the calling thread until a new TCP connection
+    /// is established. When established, the corresponding [`TcpStream`] and the
+    /// remote peer's address will be returned.
+    ///
+    /// # Examples
+    ///
+    /// ```no_run
+    /// use std::net::TcpListener;
+    ///
+    /// let listener = TcpListener::bind("127.0.0.1:8080").unwrap();
+    /// match listener.accept() {
+    ///     Ok((_socket, addr)) => println!("new client: {addr:?}"),
+    ///     Err(e) => println!("couldn't get client: {e:?}"),
+    /// }
+    /// ```
+    #[stable(feature = "rust1", since = "1.0.0")]
+    pub fn accept(&self) -> io::Result<(TcpStream, SocketAddr)> {
+        // On WASM, `TcpStream` is uninhabited (as it's unsupported) and so
+        // the `a` variable here is technically unused.
+        #[cfg_attr(target_arch = "wasm32", allow(unused_variables))]
+        self.0.accept().map(|(a, b)| (TcpStream(a), b))
+    }
+
+    /// Returns an iterator over the connections being received on this
+    /// listener.
+    ///
+    /// The returned iterator will never return [`None`] and will also not yield
+    /// the peer's [`SocketAddr`] structure. Iterating over it is equivalent to
+    /// calling [`TcpListener::accept`] in a loop.
+    ///
+    /// # Examples
+    ///
+    /// ```no_run
+    /// use std::net::{TcpListener, TcpStream};
+    ///
+    /// fn handle_connection(stream: TcpStream) {
+    ///    //...
+    /// }
+    ///
+    /// fn main() -> std::io::Result<()> {
+    ///     let listener = TcpListener::bind("127.0.0.1:80").unwrap();
+    ///
+    ///     for stream in listener.incoming() {
+    ///         match stream {
+    ///             Ok(stream) => {
+    ///                 handle_connection(stream);
+    ///             }
+    ///             Err(e) => { /* connection failed */ }
+    ///         }
+    ///     }
+    ///     Ok(())
+    /// }
+    /// ```
+    #[stable(feature = "rust1", since = "1.0.0")]
+    pub fn incoming(&self) -> Incoming<'_> {
+        Incoming { listener: self }
+    }
+
+    /// Turn this into an iterator over the connections being received on this
+    /// listener.
+    ///
+    /// The returned iterator will never return [`None`] and will also not yield
+    /// the peer's [`SocketAddr`] structure. Iterating over it is equivalent to
+    /// calling [`TcpListener::accept`] in a loop.
+    ///
+    /// # Examples
+    ///
+    /// ```no_run
+    /// #![feature(tcplistener_into_incoming)]
+    /// use std::net::{TcpListener, TcpStream};
+    ///
+    /// fn listen_on(port: u16) -> impl Iterator<Item = TcpStream> {
+    ///     let listener = TcpListener::bind("127.0.0.1:80").unwrap();
+    ///     listener.into_incoming()
+    ///         .filter_map(Result::ok) /* Ignore failed connections */
+    /// }
+    ///
+    /// fn main() -> std::io::Result<()> {
+    ///     for stream in listen_on(80) {
+    ///         /* handle the connection here */
+    ///     }
+    ///     Ok(())
+    /// }
+    /// ```
+    #[must_use = "`self` will be dropped if the result is not used"]
+    #[unstable(feature = "tcplistener_into_incoming", issue = "88339")]
+    pub fn into_incoming(self) -> IntoIncoming {
+        IntoIncoming { listener: self }
+    }
+
+    /// Sets the value for the `IP_TTL` option on this socket.
+    ///
+    /// This value sets the time-to-live field that is used in every packet sent
+    /// from this socket.
+    ///
+    /// # Examples
+    ///
+    /// ```no_run
+    /// use std::net::TcpListener;
+    ///
+    /// let listener = TcpListener::bind("127.0.0.1:80").unwrap();
+    /// listener.set_ttl(100).expect("could not set TTL");
+    /// ```
+    #[stable(feature = "net2_mutators", since = "1.9.0")]
+    pub fn set_ttl(&self, ttl: u32) -> io::Result<()> {
+        self.0.set_ttl(ttl)
+    }
+
+    /// Gets the value of the `IP_TTL` option for this socket.
+    ///
+    /// For more information about this option, see [`TcpListener::set_ttl`].
+    ///
+    /// # Examples
+    ///
+    /// ```no_run
+    /// use std::net::TcpListener;
+    ///
+    /// let listener = TcpListener::bind("127.0.0.1:80").unwrap();
+    /// listener.set_ttl(100).expect("could not set TTL");
+    /// assert_eq!(listener.ttl().unwrap_or(0), 100);
+    /// ```
+    #[stable(feature = "net2_mutators", since = "1.9.0")]
+    pub fn ttl(&self) -> io::Result<u32> {
+        self.0.ttl()
+    }
+
+    #[stable(feature = "net2_mutators", since = "1.9.0")]
+    #[deprecated(since = "1.16.0", note = "this option can only be set before the socket is bound")]
+    #[allow(missing_docs)]
+    pub fn set_only_v6(&self, only_v6: bool) -> io::Result<()> {
+        self.0.set_only_v6(only_v6)
+    }
+
+    #[stable(feature = "net2_mutators", since = "1.9.0")]
+    #[deprecated(since = "1.16.0", note = "this option can only be set before the socket is bound")]
+    #[allow(missing_docs)]
+    pub fn only_v6(&self) -> io::Result<bool> {
+        self.0.only_v6()
+    }
+
+    /// Gets the value of the `SO_ERROR` option on this socket.
+    ///
+    /// This will retrieve the stored error in the underlying socket, clearing
+    /// the field in the process. This can be useful for checking errors between
+    /// calls.
+    ///
+    /// # Examples
+    ///
+    /// ```no_run
+    /// use std::net::TcpListener;
+    ///
+    /// let listener = TcpListener::bind("127.0.0.1:80").unwrap();
+    /// listener.take_error().expect("No error was expected");
+    /// ```
+    #[stable(feature = "net2_mutators", since = "1.9.0")]
+    pub fn take_error(&self) -> io::Result<Option<io::Error>> {
+        self.0.take_error()
+    }
+
+    /// Moves this TCP stream into or out of nonblocking mode.
+    ///
+    /// This will result in the `accept` operation becoming nonblocking,
+    /// i.e., immediately returning from their calls. If the IO operation is
+    /// successful, `Ok` is returned and no further action is required. If the
+    /// IO operation could not be completed and needs to be retried, an error
+    /// with kind [`io::ErrorKind::WouldBlock`] is returned.
+    ///
+    /// On Unix platforms, calling this method corresponds to calling `fcntl`
+    /// `FIONBIO`. On Windows calling this method corresponds to calling
+    /// `ioctlsocket` `FIONBIO`.
+    ///
+    /// # Examples
+    ///
+    /// Bind a TCP listener to an address, listen for connections, and read
+    /// bytes in nonblocking mode:
+    ///
+    /// ```no_run
+    /// use std::io;
+    /// use std::net::TcpListener;
+    ///
+    /// let listener = TcpListener::bind("127.0.0.1:7878").unwrap();
+    /// listener.set_nonblocking(true).expect("Cannot set non-blocking");
+    ///
+    /// # fn wait_for_fd() { unimplemented!() }
+    /// # fn handle_connection(stream: std::net::TcpStream) { unimplemented!() }
+    /// for stream in listener.incoming() {
+    ///     match stream {
+    ///         Ok(s) => {
+    ///             // do something with the TcpStream
+    ///             handle_connection(s);
+    ///         }
+    ///         Err(ref e) if e.kind() == io::ErrorKind::WouldBlock => {
+    ///             // wait until network socket is ready, typically implemented
+    ///             // via platform-specific APIs such as epoll or IOCP
+    ///             wait_for_fd();
+    ///             continue;
+    ///         }
+    ///         Err(e) => panic!("encountered IO error: {e}"),
+    ///     }
+    /// }
+    /// ```
+    #[stable(feature = "net2_mutators", since = "1.9.0")]
+    pub fn set_nonblocking(&self, nonblocking: bool) -> io::Result<()> {
+        self.0.set_nonblocking(nonblocking)
+    }
+}
+
+// In addition to the `impl`s here, `TcpListener` also has `impl`s for
+// `AsFd`/`From<OwnedFd>`/`Into<OwnedFd>` and
+// `AsRawFd`/`IntoRawFd`/`FromRawFd`, on Unix and WASI, and
+// `AsSocket`/`From<OwnedSocket>`/`Into<OwnedSocket>` and
+// `AsRawSocket`/`IntoRawSocket`/`FromRawSocket` on Windows.
+
+#[stable(feature = "rust1", since = "1.0.0")]
+impl<'a> Iterator for Incoming<'a> {
+    type Item = io::Result<TcpStream>;
+    fn next(&mut self) -> Option<io::Result<TcpStream>> {
+        Some(self.listener.accept().map(|p| p.0))
+    }
+}
+
+#[stable(feature = "tcp_listener_incoming_fused_iterator", since = "1.64.0")]
+impl FusedIterator for Incoming<'_> {}
+
+#[unstable(feature = "tcplistener_into_incoming", issue = "88339")]
+impl Iterator for IntoIncoming {
+    type Item = io::Result<TcpStream>;
+    fn next(&mut self) -> Option<io::Result<TcpStream>> {
+        Some(self.listener.accept().map(|p| p.0))
+    }
+}
+
+#[unstable(feature = "tcplistener_into_incoming", issue = "88339")]
+impl FusedIterator for IntoIncoming {}
+
+impl AsInner<net_imp::TcpListener> for TcpListener {
+    fn as_inner(&self) -> &net_imp::TcpListener {
+        &self.0
+    }
+}
+
+impl FromInner<net_imp::TcpListener> for TcpListener {
+    fn from_inner(inner: net_imp::TcpListener) -> TcpListener {
+        TcpListener(inner)
+    }
+}
+
+impl IntoInner<net_imp::TcpListener> for TcpListener {
+    fn into_inner(self) -> net_imp::TcpListener {
+        self.0
+    }
+}
+
+#[stable(feature = "rust1", since = "1.0.0")]
+impl fmt::Debug for TcpListener {
+    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
+        self.0.fmt(f)
+    }
+}
diff --git a/library/std/src/net/tcp/tests.rs b/library/std/src/net/tcp/tests.rs
new file mode 100644
index 000000000..8c0adcfb0
--- /dev/null
+++ b/library/std/src/net/tcp/tests.rs
@@ -0,0 +1,876 @@
+use crate::fmt;
+use crate::io::prelude::*;
+use crate::io::{ErrorKind, IoSlice, IoSliceMut};
+use crate::net::test::{next_test_ip4, next_test_ip6};
+use crate::net::*;
+use crate::sync::mpsc::channel;
+use crate::thread;
+use crate::time::{Duration, Instant};
+
+fn each_ip(f: &mut dyn FnMut(SocketAddr)) {
+    f(next_test_ip4());
+    f(next_test_ip6());
+}
+
+macro_rules! t {
+    ($e:expr) => {
+        match $e {
+            Ok(t) => t,
+            Err(e) => panic!("received error for `{}`: {}", stringify!($e), e),
+        }
+    };
+}
+
+#[test]
+fn bind_error() {
+    match TcpListener::bind("1.1.1.1:9999") {
+        Ok(..) => panic!(),
+        Err(e) => assert_eq!(e.kind(), ErrorKind::AddrNotAvailable),
+    }
+}
+
+#[test]
+fn connect_error() {
+    match TcpStream::connect("0.0.0.0:1") {
+        Ok(..) => panic!(),
+        Err(e) => assert!(
+            e.kind() == ErrorKind::ConnectionRefused
+                || e.kind() == ErrorKind::InvalidInput
+                || e.kind() == ErrorKind::AddrInUse
+                || e.kind() == ErrorKind::AddrNotAvailable,
+            "bad error: {} {:?}",
+            e,
+            e.kind()
+        ),
+    }
+}
+
+#[test]
+fn listen_localhost() {
+    let socket_addr = next_test_ip4();
+    let listener = t!(TcpListener::bind(&socket_addr));
+
+    let _t = thread::spawn(move || {
+        let mut stream = t!(TcpStream::connect(&("localhost", socket_addr.port())));
+        t!(stream.write(&[144]));
+    });
+
+    let mut stream = t!(listener.accept()).0;
+    let mut buf = [0];
+    t!(stream.read(&mut buf));
+    assert!(buf[0] == 144);
+}
+
+#[test]
+fn connect_loopback() {
+    each_ip(&mut |addr| {
+        let acceptor = t!(TcpListener::bind(&addr));
+
+        let _t = thread::spawn(move || {
+            let host = match addr {
+                SocketAddr::V4(..) => "127.0.0.1",
+                SocketAddr::V6(..) => "::1",
+            };
+            let mut stream = t!(TcpStream::connect(&(host, addr.port())));
+            t!(stream.write(&[66]));
+        });
+
+        let mut stream = t!(acceptor.accept()).0;
+        let mut buf = [0];
+        t!(stream.read(&mut buf));
+        assert!(buf[0] == 66);
+    })
+}
+
+#[test]
+fn smoke_test() {
+    each_ip(&mut |addr| {
+        let acceptor = t!(TcpListener::bind(&addr));
+
+        let (tx, rx) = channel();
+        let _t = thread::spawn(move || {
+            let mut stream = t!(TcpStream::connect(&addr));
+            t!(stream.write(&[99]));
+            tx.send(t!(stream.local_addr())).unwrap();
+        });
+
+        let (mut stream, addr) = t!(acceptor.accept());
+        let mut buf = [0];
+        t!(stream.read(&mut buf));
+        assert!(buf[0] == 99);
+        assert_eq!(addr, t!(rx.recv()));
+    })
+}
+
+#[test]
+fn read_eof() {
+    each_ip(&mut |addr| {
+        let acceptor = t!(TcpListener::bind(&addr));
+
+        let _t = thread::spawn(move || {
+            let _stream = t!(TcpStream::connect(&addr));
+            // Close
+        });
+
+        let mut stream = t!(acceptor.accept()).0;
+        let mut buf = [0];
+        let nread = t!(stream.read(&mut buf));
+        assert_eq!(nread, 0);
+        let nread = t!(stream.read(&mut buf));
+        assert_eq!(nread, 0);
+    })
+}
+
+#[test]
+fn write_close() {
+    each_ip(&mut |addr| {
+        let acceptor = t!(TcpListener::bind(&addr));
+
+        let (tx, rx) = channel();
+        let _t = thread::spawn(move || {
+            drop(t!(TcpStream::connect(&addr)));
+            tx.send(()).unwrap();
+        });
+
+        let mut stream = t!(acceptor.accept()).0;
+        rx.recv().unwrap();
+        let buf = [0];
+        match stream.write(&buf) {
+            Ok(..) => {}
+            Err(e) => {
+                assert!(
+                    e.kind() == ErrorKind::ConnectionReset
+                        || e.kind() == ErrorKind::BrokenPipe
+                        || e.kind() == ErrorKind::ConnectionAborted,
+                    "unknown error: {e}"
+                );
+            }
+        }
+    })
+}
+
+#[test]
+fn multiple_connect_serial() {
+    each_ip(&mut |addr| {
+        let max = 10;
+        let acceptor = t!(TcpListener::bind(&addr));
+
+        let _t = thread::spawn(move || {
+            for _ in 0..max {
+                let mut stream = t!(TcpStream::connect(&addr));
+                t!(stream.write(&[99]));
+            }
+        });
+
+        for stream in acceptor.incoming().take(max) {
+            let mut stream = t!(stream);
+            let mut buf = [0];
+            t!(stream.read(&mut buf));
+            assert_eq!(buf[0], 99);
+        }
+    })
+}
+
+#[test]
+fn multiple_connect_interleaved_greedy_schedule() {
+    const MAX: usize = 10;
+    each_ip(&mut |addr| {
+        let acceptor = t!(TcpListener::bind(&addr));
+
+        let _t = thread::spawn(move || {
+            let acceptor = acceptor;
+            for (i, stream) in acceptor.incoming().enumerate().take(MAX) {
+                // Start another thread to handle the connection
+                let _t = thread::spawn(move || {
+                    let mut stream = t!(stream);
+                    let mut buf = [0];
+                    t!(stream.read(&mut buf));
+                    assert!(buf[0] == i as u8);
+                });
+            }
+        });
+
+        connect(0, addr);
+    });
+
+    fn connect(i: usize, addr: SocketAddr) {
+        if i == MAX {
+            return;
+        }
+
+        let t = thread::spawn(move || {
+            let mut stream = t!(TcpStream::connect(&addr));
+            // Connect again before writing
+            connect(i + 1, addr);
+            t!(stream.write(&[i as u8]));
+        });
+        t.join().ok().expect("thread panicked");
+    }
+}
+
+#[test]
+fn multiple_connect_interleaved_lazy_schedule() {
+    const MAX: usize = 10;
+    each_ip(&mut |addr| {
+        let acceptor = t!(TcpListener::bind(&addr));
+
+        let _t = thread::spawn(move || {
+            for stream in acceptor.incoming().take(MAX) {
+                // Start another thread to handle the connection
+                let _t = thread::spawn(move || {
+                    let mut stream = t!(stream);
+                    let mut buf = [0];
+                    t!(stream.read(&mut buf));
+                    assert!(buf[0] == 99);
+                });
+            }
+        });
+
+        connect(0, addr);
+    });
+
+    fn connect(i: usize, addr: SocketAddr) {
+        if i == MAX {
+            return;
+        }
+
+        let t = thread::spawn(move || {
+            let mut stream = t!(TcpStream::connect(&addr));
+            connect(i + 1, addr);
+            t!(stream.write(&[99]));
+        });
+        t.join().ok().expect("thread panicked");
+    }
+}
+
+#[test]
+fn socket_and_peer_name() {
+    each_ip(&mut |addr| {
+        let listener = t!(TcpListener::bind(&addr));
+        let so_name = t!(listener.local_addr());
+        assert_eq!(addr, so_name);
+        let _t = thread::spawn(move || {
+            t!(listener.accept());
+        });
+
+        let stream = t!(TcpStream::connect(&addr));
+        assert_eq!(addr, t!(stream.peer_addr()));
+    })
+}
+
+#[test]
+fn partial_read() {
+    each_ip(&mut |addr| {
+        let (tx, rx) = channel();
+        let srv = t!(TcpListener::bind(&addr));
+        let _t = thread::spawn(move || {
+            let mut cl = t!(srv.accept()).0;
+            cl.write(&[10]).unwrap();
+            let mut b = [0];
+            t!(cl.read(&mut b));
+            tx.send(()).unwrap();
+        });
+
+        let mut c = t!(TcpStream::connect(&addr));
+        let mut b = [0; 10];
+        assert_eq!(c.read(&mut b).unwrap(), 1);
+        t!(c.write(&[1]));
+        rx.recv().unwrap();
+    })
+}
+
+#[test]
+fn read_vectored() {
+    each_ip(&mut |addr| {
+        let srv = t!(TcpListener::bind(&addr));
+        let mut s1 = t!(TcpStream::connect(&addr));
+        let mut s2 = t!(srv.accept()).0;
+
+        let len = s1.write(&[10, 11, 12]).unwrap();
+        assert_eq!(len, 3);
+
+        let mut a = [];
+        let mut b = [0];
+        let mut c = [0; 3];
+        let len = t!(s2.read_vectored(&mut [
+            IoSliceMut::new(&mut a),
+            IoSliceMut::new(&mut b),
+            IoSliceMut::new(&mut c)
+        ],));
+        assert!(len > 0);
+        assert_eq!(b, [10]);
+        // some implementations don't support readv, so we may only fill the first buffer
+        assert!(len == 1 || c == [11, 12, 0]);
+    })
+}
+
+#[test]
+fn write_vectored() {
+    each_ip(&mut |addr| {
+        let srv = t!(TcpListener::bind(&addr));
+        let mut s1 = t!(TcpStream::connect(&addr));
+        let mut s2 = t!(srv.accept()).0;
+
+        let a = [];
+        let b = [10];
+        let c = [11, 12];
+        t!(s1.write_vectored(&[IoSlice::new(&a), IoSlice::new(&b), IoSlice::new(&c)]));
+
+        let mut buf = [0; 4];
+        let len = t!(s2.read(&mut buf));
+        // some implementations don't support writev, so we may only write the first buffer
+        if len == 1 {
+            assert_eq!(buf, [10, 0, 0, 0]);
+        } else {
+            assert_eq!(len, 3);
+            assert_eq!(buf, [10, 11, 12, 0]);
+        }
+    })
+}
+
+#[test]
+fn double_bind() {
+    each_ip(&mut |addr| {
+        let listener1 = t!(TcpListener::bind(&addr));
+        match TcpListener::bind(&addr) {
+            Ok(listener2) => panic!(
+                "This system (perhaps due to options set by TcpListener::bind) \
+                 permits double binding: {:?} and {:?}",
+                listener1, listener2
+            ),
+            Err(e) => {
+                assert!(
+                    e.kind() == ErrorKind::ConnectionRefused
+                        || e.kind() == ErrorKind::Uncategorized
+                        || e.kind() == ErrorKind::AddrInUse,
+                    "unknown error: {} {:?}",
+                    e,
+                    e.kind()
+                );
+            }
+        }
+    })
+}
+
+#[test]
+fn tcp_clone_smoke() {
+    each_ip(&mut |addr| {
+        let acceptor = t!(TcpListener::bind(&addr));
+
+        let _t = thread::spawn(move || {
+            let mut s = t!(TcpStream::connect(&addr));
+            let mut buf = [0, 0];
+            assert_eq!(s.read(&mut buf).unwrap(), 1);
+            assert_eq!(buf[0], 1);
+            t!(s.write(&[2]));
+        });
+
+        let mut s1 = t!(acceptor.accept()).0;
+        let s2 = t!(s1.try_clone());
+
+        let (tx1, rx1) = channel();
+        let (tx2, rx2) = channel();
+        let _t = thread::spawn(move || {
+            let mut s2 = s2;
+            rx1.recv().unwrap();
+            t!(s2.write(&[1]));
+            tx2.send(()).unwrap();
+        });
+        tx1.send(()).unwrap();
+        let mut buf = [0, 0];
+        assert_eq!(s1.read(&mut buf).unwrap(), 1);
+        rx2.recv().unwrap();
+    })
+}
+
+#[test]
+fn tcp_clone_two_read() {
+    each_ip(&mut |addr| {
+        let acceptor = t!(TcpListener::bind(&addr));
+        let (tx1, rx) = channel();
+        let tx2 = tx1.clone();
+
+        let _t = thread::spawn(move || {
+            let mut s = t!(TcpStream::connect(&addr));
+            t!(s.write(&[1]));
+            rx.recv().unwrap();
+            t!(s.write(&[2]));
+            rx.recv().unwrap();
+        });
+
+        let mut s1 = t!(acceptor.accept()).0;
+        let s2 = t!(s1.try_clone());
+
+        let (done, rx) = channel();
+        let _t = thread::spawn(move || {
+            let mut s2 = s2;
+            let mut buf = [0, 0];
+            t!(s2.read(&mut buf));
+            tx2.send(()).unwrap();
+            done.send(()).unwrap();
+        });
+        let mut buf = [0, 0];
+        t!(s1.read(&mut buf));
+        tx1.send(()).unwrap();
+
+        rx.recv().unwrap();
+    })
+}
+
+#[test]
+fn tcp_clone_two_write() {
+    each_ip(&mut |addr| {
+        let acceptor = t!(TcpListener::bind(&addr));
+
+        let _t = thread::spawn(move || {
+            let mut s = t!(TcpStream::connect(&addr));
+            let mut buf = [0, 1];
+            t!(s.read(&mut buf));
+            t!(s.read(&mut buf));
+        });
+
+        let mut s1 = t!(acceptor.accept()).0;
+        let s2 = t!(s1.try_clone());
+
+        let (done, rx) = channel();
+        let _t = thread::spawn(move || {
+            let mut s2 = s2;
+            t!(s2.write(&[1]));
+            done.send(()).unwrap();
+        });
+        t!(s1.write(&[2]));
+
+        rx.recv().unwrap();
+    })
+}
+
+#[test]
+// FIXME: https://github.com/fortanix/rust-sgx/issues/110
+#[cfg_attr(target_env = "sgx", ignore)]
+fn shutdown_smoke() {
+    each_ip(&mut |addr| {
+        let a = t!(TcpListener::bind(&addr));
+        let _t = thread::spawn(move || {
+            let mut c = t!(a.accept()).0;
+            let mut b = [0];
+            assert_eq!(c.read(&mut b).unwrap(), 0);
+            t!(c.write(&[1]));
+        });
+
+        let mut s = t!(TcpStream::connect(&addr));
+        t!(s.shutdown(Shutdown::Write));
+        assert!(s.write(&[1]).is_err());
+        let mut b = [0, 0];
+        assert_eq!(t!(s.read(&mut b)), 1);
+        assert_eq!(b[0], 1);
+    })
+}
+
+#[test]
+// FIXME: https://github.com/fortanix/rust-sgx/issues/110
+#[cfg_attr(target_env = "sgx", ignore)]
+fn close_readwrite_smoke() {
+    each_ip(&mut |addr| {
+        let a = t!(TcpListener::bind(&addr));
+        let (tx, rx) = channel::<()>();
+        let _t = thread::spawn(move || {
+            let _s = t!(a.accept());
+            let _ = rx.recv();
+        });
+
+        let mut b = [0];
+        let mut s = t!(TcpStream::connect(&addr));
+        let mut s2 = t!(s.try_clone());
+
+        // closing should prevent reads/writes
+        t!(s.shutdown(Shutdown::Write));
+        assert!(s.write(&[0]).is_err());
+        t!(s.shutdown(Shutdown::Read));
+        assert_eq!(s.read(&mut b).unwrap(), 0);
+
+        // closing should affect previous handles
+        assert!(s2.write(&[0]).is_err());
+        assert_eq!(s2.read(&mut b).unwrap(), 0);
+
+        // closing should affect new handles
+        let mut s3 = t!(s.try_clone());
+        assert!(s3.write(&[0]).is_err());
+        assert_eq!(s3.read(&mut b).unwrap(), 0);
+
+        // make sure these don't die
+        let _ = s2.shutdown(Shutdown::Read);
+        let _ = s2.shutdown(Shutdown::Write);
+        let _ = s3.shutdown(Shutdown::Read);
+        let _ = s3.shutdown(Shutdown::Write);
+        drop(tx);
+    })
+}
+
+#[test]
+#[cfg_attr(target_env = "sgx", ignore)]
+fn close_read_wakes_up() {
+    each_ip(&mut |addr| {
+        let a = t!(TcpListener::bind(&addr));
+        let (tx1, rx) = channel::<()>();
+        let _t = thread::spawn(move || {
+            let _s = t!(a.accept());
+            let _ = rx.recv();
+        });
+
+        let s = t!(TcpStream::connect(&addr));
+        let s2 = t!(s.try_clone());
+        let (tx, rx) = channel();
+        let _t = thread::spawn(move || {
+            let mut s2 = s2;
+            assert_eq!(t!(s2.read(&mut [0])), 0);
+            tx.send(()).unwrap();
+        });
+        // this should wake up the child thread
+        t!(s.shutdown(Shutdown::Read));
+
+        // this test will never finish if the child doesn't wake up
+        rx.recv().unwrap();
+        drop(tx1);
+    })
+}
+
+#[test]
+fn clone_while_reading() {
+    each_ip(&mut |addr| {
+        let accept = t!(TcpListener::bind(&addr));
+
+        // Enqueue a thread to write to a socket
+        let (tx, rx) = channel();
+        let (txdone, rxdone) = channel();
+        let txdone2 = txdone.clone();
+        let _t = thread::spawn(move || {
+            let mut tcp = t!(TcpStream::connect(&addr));
+            rx.recv().unwrap();
+            t!(tcp.write(&[0]));
+            txdone2.send(()).unwrap();
+        });
+
+        // Spawn off a reading clone
+        let tcp = t!(accept.accept()).0;
+        let tcp2 = t!(tcp.try_clone());
+        let txdone3 = txdone.clone();
+        let _t = thread::spawn(move || {
+            let mut tcp2 = tcp2;
+            t!(tcp2.read(&mut [0]));
+            txdone3.send(()).unwrap();
+        });
+
+        // Try to ensure that the reading clone is indeed reading
+        for _ in 0..50 {
+            thread::yield_now();
+        }
+
+        // clone the handle again while it's reading, then let it finish the
+        // read.
+        let _ = t!(tcp.try_clone());
+        tx.send(()).unwrap();
+        rxdone.recv().unwrap();
+        rxdone.recv().unwrap();
+    })
+}
+
+#[test]
+fn clone_accept_smoke() {
+    each_ip(&mut |addr| {
+        let a = t!(TcpListener::bind(&addr));
+        let a2 = t!(a.try_clone());
+
+        let _t = thread::spawn(move || {
+            let _ = TcpStream::connect(&addr);
+        });
+        let _t = thread::spawn(move || {
+            let _ = TcpStream::connect(&addr);
+        });
+
+        t!(a.accept());
+        t!(a2.accept());
+    })
+}
+
+#[test]
+fn clone_accept_concurrent() {
+    each_ip(&mut |addr| {
+        let a = t!(TcpListener::bind(&addr));
+        let a2 = t!(a.try_clone());
+
+        let (tx, rx) = channel();
+        let tx2 = tx.clone();
+
+        let _t = thread::spawn(move || {
+            tx.send(t!(a.accept())).unwrap();
+        });
+        let _t = thread::spawn(move || {
+            tx2.send(t!(a2.accept())).unwrap();
+        });
+
+        let _t = thread::spawn(move || {
+            let _ = TcpStream::connect(&addr);
+        });
+        let _t = thread::spawn(move || {
+            let _ = TcpStream::connect(&addr);
+        });
+
+        rx.recv().unwrap();
+        rx.recv().unwrap();
+    })
+}
+
+#[test]
+fn debug() {
+    #[cfg(not(target_env = "sgx"))]
+    fn render_socket_addr<'a>(addr: &'a SocketAddr) -> impl fmt::Debug + 'a {
+        addr
+    }
+    #[cfg(target_env = "sgx")]
+    fn render_socket_addr<'a>(addr: &'a SocketAddr) -> impl fmt::Debug + 'a {
+        addr.to_string()
+    }
+
+    #[cfg(target_env = "sgx")]
+    use crate::os::fortanix_sgx::io::AsRawFd;
+    #[cfg(unix)]
+    use crate::os::unix::io::AsRawFd;
+    #[cfg(not(windows))]
+    fn render_inner(addr: &dyn AsRawFd) -> impl fmt::Debug {
+        addr.as_raw_fd()
+    }
+    #[cfg(windows)]
+    fn render_inner(addr: &dyn crate::os::windows::io::AsRawSocket) -> impl fmt::Debug {
+        addr.as_raw_socket()
+    }
+
+    let inner_name = if cfg!(windows) { "socket" } else { "fd" };
+    let socket_addr = next_test_ip4();
+
+    let listener = t!(TcpListener::bind(&socket_addr));
+    let compare = format!(
+        "TcpListener {{ addr: {:?}, {}: {:?} }}",
+        render_socket_addr(&socket_addr),
+        inner_name,
+        render_inner(&listener)
+    );
+    assert_eq!(format!("{listener:?}"), compare);
+
+    let stream = t!(TcpStream::connect(&("localhost", socket_addr.port())));
+    let compare = format!(
+        "TcpStream {{ addr: {:?}, peer: {:?}, {}: {:?} }}",
+        render_socket_addr(&stream.local_addr().unwrap()),
+        render_socket_addr(&stream.peer_addr().unwrap()),
+        inner_name,
+        render_inner(&stream)
+    );
+    assert_eq!(format!("{stream:?}"), compare);
+}
+
+// FIXME: re-enabled openbsd tests once their socket timeout code
+//        no longer has rounding errors.
+// VxWorks ignores SO_SNDTIMEO.
+#[cfg_attr(any(target_os = "netbsd", target_os = "openbsd", target_os = "vxworks"), ignore)]
+#[cfg_attr(target_env = "sgx", ignore)] // FIXME: https://github.com/fortanix/rust-sgx/issues/31
+#[test]
+fn timeouts() {
+    let addr = next_test_ip4();
+    let listener = t!(TcpListener::bind(&addr));
+
+    let stream = t!(TcpStream::connect(&("localhost", addr.port())));
+    let dur = Duration::new(15410, 0);
+
+    assert_eq!(None, t!(stream.read_timeout()));
+
+    t!(stream.set_read_timeout(Some(dur)));
+    assert_eq!(Some(dur), t!(stream.read_timeout()));
+
+    assert_eq!(None, t!(stream.write_timeout()));
+
+    t!(stream.set_write_timeout(Some(dur)));
+    assert_eq!(Some(dur), t!(stream.write_timeout()));
+
+    t!(stream.set_read_timeout(None));
+    assert_eq!(None, t!(stream.read_timeout()));
+
+    t!(stream.set_write_timeout(None));
+    assert_eq!(None, t!(stream.write_timeout()));
+    drop(listener);
+}
+
+#[test]
+#[cfg_attr(target_env = "sgx", ignore)] // FIXME: https://github.com/fortanix/rust-sgx/issues/31
+fn test_read_timeout() {
+    let addr = next_test_ip4();
+    let listener = t!(TcpListener::bind(&addr));
+
+    let mut stream = t!(TcpStream::connect(&("localhost", addr.port())));
+    t!(stream.set_read_timeout(Some(Duration::from_millis(1000))));
+
+    let mut buf = [0; 10];
+    let start = Instant::now();
+    let kind = stream.read_exact(&mut buf).err().expect("expected error").kind();
+    assert!(
+        kind == ErrorKind::WouldBlock || kind == ErrorKind::TimedOut,
+        "unexpected_error: {:?}",
+        kind
+    );
+    assert!(start.elapsed() > Duration::from_millis(400));
+    drop(listener);
+}
+
+#[test]
+#[cfg_attr(target_env = "sgx", ignore)] // FIXME: https://github.com/fortanix/rust-sgx/issues/31
+fn test_read_with_timeout() {
+    let addr = next_test_ip4();
+    let listener = t!(TcpListener::bind(&addr));
+
+    let mut stream = t!(TcpStream::connect(&("localhost", addr.port())));
+    t!(stream.set_read_timeout(Some(Duration::from_millis(1000))));
+
+    let mut other_end = t!(listener.accept()).0;
+    t!(other_end.write_all(b"hello world"));
+
+    let mut buf = [0; 11];
+    t!(stream.read(&mut buf));
+    assert_eq!(b"hello world", &buf[..]);
+
+    let start = Instant::now();
+    let kind = stream.read_exact(&mut buf).err().expect("expected error").kind();
+    assert!(
+        kind == ErrorKind::WouldBlock || kind == ErrorKind::TimedOut,
+        "unexpected_error: {:?}",
+        kind
+    );
+    assert!(start.elapsed() > Duration::from_millis(400));
+    drop(listener);
+}
+
+// Ensure the `set_read_timeout` and `set_write_timeout` calls return errors
+// when passed zero Durations
+#[test]
+fn test_timeout_zero_duration() {
+    let addr = next_test_ip4();
+
+    let listener = t!(TcpListener::bind(&addr));
+    let stream = t!(TcpStream::connect(&addr));
+
+    let result = stream.set_write_timeout(Some(Duration::new(0, 0)));
+    let err = result.unwrap_err();
+    assert_eq!(err.kind(), ErrorKind::InvalidInput);
+
+    let result = stream.set_read_timeout(Some(Duration::new(0, 0)));
+    let err = result.unwrap_err();
+    assert_eq!(err.kind(), ErrorKind::InvalidInput);
+
+    drop(listener);
+}
+
+#[test]
+#[cfg_attr(target_env = "sgx", ignore)]
+fn linger() {
+    let addr = next_test_ip4();
+    let _listener = t!(TcpListener::bind(&addr));
+
+    let stream = t!(TcpStream::connect(&("localhost", addr.port())));
+
+    assert_eq!(None, t!(stream.linger()));
+    t!(stream.set_linger(Some(Duration::from_secs(1))));
+    assert_eq!(Some(Duration::from_secs(1)), t!(stream.linger()));
+    t!(stream.set_linger(None));
+    assert_eq!(None, t!(stream.linger()));
+}
+
+#[test]
+#[cfg_attr(target_env = "sgx", ignore)]
+fn nodelay() {
+    let addr = next_test_ip4();
+    let _listener = t!(TcpListener::bind(&addr));
+
+    let stream = t!(TcpStream::connect(&("localhost", addr.port())));
+
+    assert_eq!(false, t!(stream.nodelay()));
+    t!(stream.set_nodelay(true));
+    assert_eq!(true, t!(stream.nodelay()));
+    t!(stream.set_nodelay(false));
+    assert_eq!(false, t!(stream.nodelay()));
+}
+
+#[test]
+#[cfg_attr(target_env = "sgx", ignore)]
+fn ttl() {
+    let ttl = 100;
+
+    let addr = next_test_ip4();
+    let listener = t!(TcpListener::bind(&addr));
+
+    t!(listener.set_ttl(ttl));
+    assert_eq!(ttl, t!(listener.ttl()));
+
+    let stream = t!(TcpStream::connect(&("localhost", addr.port())));
+
+    t!(stream.set_ttl(ttl));
+    assert_eq!(ttl, t!(stream.ttl()));
+}
+
+#[test]
+#[cfg_attr(target_env = "sgx", ignore)]
+fn set_nonblocking() {
+    let addr = next_test_ip4();
+    let listener = t!(TcpListener::bind(&addr));
+
+    t!(listener.set_nonblocking(true));
+    t!(listener.set_nonblocking(false));
+
+    let mut stream = t!(TcpStream::connect(&("localhost", addr.port())));
+
+    t!(stream.set_nonblocking(false));
+    t!(stream.set_nonblocking(true));
+
+    let mut buf = [0];
+    match stream.read(&mut buf) {
+        Ok(_) => panic!("expected error"),
+        Err(ref e) if e.kind() == ErrorKind::WouldBlock => {}
+        Err(e) => panic!("unexpected error {e}"),
+    }
+}
+
+#[test]
+#[cfg_attr(target_env = "sgx", ignore)] // FIXME: https://github.com/fortanix/rust-sgx/issues/31
+fn peek() {
+    each_ip(&mut |addr| {
+        let (txdone, rxdone) = channel();
+
+        let srv = t!(TcpListener::bind(&addr));
+        let _t = thread::spawn(move || {
+            let mut cl = t!(srv.accept()).0;
+            cl.write(&[1, 3, 3, 7]).unwrap();
+            t!(rxdone.recv());
+        });
+
+        let mut c = t!(TcpStream::connect(&addr));
+        let mut b = [0; 10];
+        for _ in 1..3 {
+            let len = c.peek(&mut b).unwrap();
+            assert_eq!(len, 4);
+        }
+        let len = c.read(&mut b).unwrap();
+        assert_eq!(len, 4);
+
+        t!(c.set_nonblocking(true));
+        match c.peek(&mut b) {
+            Ok(_) => panic!("expected error"),
+            Err(ref e) if e.kind() == ErrorKind::WouldBlock => {}
+            Err(e) => panic!("unexpected error {e}"),
+        }
+        t!(txdone.send(()));
+    })
+}
+
+#[test]
+#[cfg_attr(target_env = "sgx", ignore)] // FIXME: https://github.com/fortanix/rust-sgx/issues/31
+fn connect_timeout_valid() {
+    let listener = TcpListener::bind("127.0.0.1:0").unwrap();
+    let addr = listener.local_addr().unwrap();
+    TcpStream::connect_timeout(&addr, Duration::from_secs(2)).unwrap();
+}
diff --git a/library/std/src/net/test.rs b/library/std/src/net/test.rs
new file mode 100644
index 000000000..37937b5ea
--- /dev/null
+++ b/library/std/src/net/test.rs
@@ -0,0 +1,60 @@
+#![allow(warnings)] // not used on emscripten
+
+use crate::env;
+use crate::net::{Ipv4Addr, Ipv6Addr, SocketAddr, SocketAddrV4, SocketAddrV6, ToSocketAddrs};
+use crate::sync::atomic::{AtomicUsize, Ordering};
+
+static PORT: AtomicUsize = AtomicUsize::new(0);
+
+pub fn next_test_ip4() -> SocketAddr {
+    let port = PORT.fetch_add(1, Ordering::SeqCst) as u16 + base_port();
+    SocketAddr::V4(SocketAddrV4::new(Ipv4Addr::new(127, 0, 0, 1), port))
+}
+
+pub fn next_test_ip6() -> SocketAddr {
+    let port = PORT.fetch_add(1, Ordering::SeqCst) as u16 + base_port();
+    SocketAddr::V6(SocketAddrV6::new(Ipv6Addr::new(0, 0, 0, 0, 0, 0, 0, 1), port, 0, 0))
+}
+
+pub fn sa4(a: Ipv4Addr, p: u16) -> SocketAddr {
+    SocketAddr::V4(SocketAddrV4::new(a, p))
+}
+
+pub fn sa6(a: Ipv6Addr, p: u16) -> SocketAddr {
+    SocketAddr::V6(SocketAddrV6::new(a, p, 0, 0))
+}
+
+pub fn tsa<A: ToSocketAddrs>(a: A) -> Result<Vec<SocketAddr>, String> {
+    match a.to_socket_addrs() {
+        Ok(a) => Ok(a.collect()),
+        Err(e) => Err(e.to_string()),
+    }
+}
+
+// The bots run multiple builds at the same time, and these builds
+// all want to use ports. This function figures out which workspace
+// it is running in and assigns a port range based on it.
+fn base_port() -> u16 {
+    let cwd = if cfg!(target_env = "sgx") {
+        String::from("sgx")
+    } else {
+        env::current_dir().unwrap().into_os_string().into_string().unwrap()
+    };
+    let dirs = [
+        "32-opt",
+        "32-nopt",
+        "musl-64-opt",
+        "cross-opt",
+        "64-opt",
+        "64-nopt",
+        "64-opt-vg",
+        "64-debug-opt",
+        "all-opt",
+        "snap3",
+        "dist",
+        "sgx",
+    ];
+    dirs.iter().enumerate().find(|&(_, dir)| cwd.contains(dir)).map(|p| p.0).unwrap_or(0) as u16
+        * 1000
+        + 19600
+}
diff --git a/library/std/src/net/udp.rs b/library/std/src/net/udp.rs
new file mode 100644
index 000000000..864e1b0f3
--- /dev/null
+++ b/library/std/src/net/udp.rs
@@ -0,0 +1,813 @@
+#[cfg(all(test, not(any(target_os = "emscripten", target_env = "sgx"))))]
+mod tests;
+
+use crate::fmt;
+use crate::io::{self, ErrorKind};
+use crate::net::{Ipv4Addr, Ipv6Addr, SocketAddr, ToSocketAddrs};
+use crate::sys_common::net as net_imp;
+use crate::sys_common::{AsInner, FromInner, IntoInner};
+use crate::time::Duration;
+
+/// A UDP socket.
+///
+/// After creating a `UdpSocket` by [`bind`]ing it to a socket address, data can be
+/// [sent to] and [received from] any other socket address.
+///
+/// Although UDP is a connectionless protocol, this implementation provides an interface
+/// to set an address where data should be sent and received from. After setting a remote
+/// address with [`connect`], data can be sent to and received from that address with
+/// [`send`] and [`recv`].
+///
+/// As stated in the User Datagram Protocol's specification in [IETF RFC 768], UDP is
+/// an unordered, unreliable protocol; refer to [`TcpListener`] and [`TcpStream`] for TCP
+/// primitives.
+///
+/// [`bind`]: UdpSocket::bind
+/// [`connect`]: UdpSocket::connect
+/// [IETF RFC 768]: https://tools.ietf.org/html/rfc768
+/// [`recv`]: UdpSocket::recv
+/// [received from]: UdpSocket::recv_from
+/// [`send`]: UdpSocket::send
+/// [sent to]: UdpSocket::send_to
+/// [`TcpListener`]: crate::net::TcpListener
+/// [`TcpStream`]: crate::net::TcpStream
+///
+/// # Examples
+///
+/// ```no_run
+/// use std::net::UdpSocket;
+///
+/// fn main() -> std::io::Result<()> {
+///     {
+///         let socket = UdpSocket::bind("127.0.0.1:34254")?;
+///
+///         // Receives a single datagram message on the socket. If `buf` is too small to hold
+///         // the message, it will be cut off.
+///         let mut buf = [0; 10];
+///         let (amt, src) = socket.recv_from(&mut buf)?;
+///
+///         // Redeclare `buf` as slice of the received data and send reverse data back to origin.
+///         let buf = &mut buf[..amt];
+///         buf.reverse();
+///         socket.send_to(buf, &src)?;
+///     } // the socket is closed here
+///     Ok(())
+/// }
+/// ```
+#[stable(feature = "rust1", since = "1.0.0")]
+pub struct UdpSocket(net_imp::UdpSocket);
+
+impl UdpSocket {
+    /// Creates a UDP socket from the given address.
+    ///
+    /// The address type can be any implementor of [`ToSocketAddrs`] trait. See
+    /// its documentation for concrete examples.
+    ///
+    /// If `addr` yields multiple addresses, `bind` will be attempted with
+    /// each of the addresses until one succeeds and returns the socket. If none
+    /// of the addresses succeed in creating a socket, the error returned from
+    /// the last attempt (the last address) is returned.
+    ///
+    /// # Examples
+    ///
+    /// Creates a UDP socket bound to `127.0.0.1:3400`:
+    ///
+    /// ```no_run
+    /// use std::net::UdpSocket;
+    ///
+    /// let socket = UdpSocket::bind("127.0.0.1:3400").expect("couldn't bind to address");
+    /// ```
+    ///
+    /// Creates a UDP socket bound to `127.0.0.1:3400`. If the socket cannot be
+    /// bound to that address, create a UDP socket bound to `127.0.0.1:3401`:
+    ///
+    /// ```no_run
+    /// use std::net::{SocketAddr, UdpSocket};
+    ///
+    /// let addrs = [
+    ///     SocketAddr::from(([127, 0, 0, 1], 3400)),
+    ///     SocketAddr::from(([127, 0, 0, 1], 3401)),
+    /// ];
+    /// let socket = UdpSocket::bind(&addrs[..]).expect("couldn't bind to address");
+    /// ```
+    #[stable(feature = "rust1", since = "1.0.0")]
+    pub fn bind<A: ToSocketAddrs>(addr: A) -> io::Result<UdpSocket> {
+        super::each_addr(addr, net_imp::UdpSocket::bind).map(UdpSocket)
+    }
+
+    /// Receives a single datagram message on the socket. On success, returns the number
+    /// of bytes read and the origin.
+    ///
+    /// The function must be called with valid byte array `buf` of sufficient size to
+    /// hold the message bytes. If a message is too long to fit in the supplied buffer,
+    /// excess bytes may be discarded.
+    ///
+    /// # Examples
+    ///
+    /// ```no_run
+    /// use std::net::UdpSocket;
+    ///
+    /// let socket = UdpSocket::bind("127.0.0.1:34254").expect("couldn't bind to address");
+    /// let mut buf = [0; 10];
+    /// let (number_of_bytes, src_addr) = socket.recv_from(&mut buf)
+    ///                                         .expect("Didn't receive data");
+    /// let filled_buf = &mut buf[..number_of_bytes];
+    /// ```
+    #[stable(feature = "rust1", since = "1.0.0")]
+    pub fn recv_from(&self, buf: &mut [u8]) -> io::Result<(usize, SocketAddr)> {
+        self.0.recv_from(buf)
+    }
+
+    /// Receives a single datagram message on the socket, without removing it from the
+    /// queue. On success, returns the number of bytes read and the origin.
+    ///
+    /// The function must be called with valid byte array `buf` of sufficient size to
+    /// hold the message bytes. If a message is too long to fit in the supplied buffer,
+    /// excess bytes may be discarded.
+    ///
+    /// Successive calls return the same data. This is accomplished by passing
+    /// `MSG_PEEK` as a flag to the underlying `recvfrom` system call.
+    ///
+    /// Do not use this function to implement busy waiting, instead use `libc::poll` to
+    /// synchronize IO events on one or more sockets.
+    ///
+    /// # Examples
+    ///
+    /// ```no_run
+    /// use std::net::UdpSocket;
+    ///
+    /// let socket = UdpSocket::bind("127.0.0.1:34254").expect("couldn't bind to address");
+    /// let mut buf = [0; 10];
+    /// let (number_of_bytes, src_addr) = socket.peek_from(&mut buf)
+    ///                                         .expect("Didn't receive data");
+    /// let filled_buf = &mut buf[..number_of_bytes];
+    /// ```
+    #[stable(feature = "peek", since = "1.18.0")]
+    pub fn peek_from(&self, buf: &mut [u8]) -> io::Result<(usize, SocketAddr)> {
+        self.0.peek_from(buf)
+    }
+
+    /// Sends data on the socket to the given address. On success, returns the
+    /// number of bytes written.
+    ///
+    /// Address type can be any implementor of [`ToSocketAddrs`] trait. See its
+    /// documentation for concrete examples.
+    ///
+    /// It is possible for `addr` to yield multiple addresses, but `send_to`
+    /// will only send data to the first address yielded by `addr`.
+    ///
+    /// This will return an error when the IP version of the local socket
+    /// does not match that returned from [`ToSocketAddrs`].
+    ///
+    /// See [Issue #34202] for more details.
+    ///
+    /// # Examples
+    ///
+    /// ```no_run
+    /// use std::net::UdpSocket;
+    ///
+    /// let socket = UdpSocket::bind("127.0.0.1:34254").expect("couldn't bind to address");
+    /// socket.send_to(&[0; 10], "127.0.0.1:4242").expect("couldn't send data");
+    /// ```
+    ///
+    /// [Issue #34202]: https://github.com/rust-lang/rust/issues/34202
+    #[stable(feature = "rust1", since = "1.0.0")]
+    pub fn send_to<A: ToSocketAddrs>(&self, buf: &[u8], addr: A) -> io::Result<usize> {
+        match addr.to_socket_addrs()?.next() {
+            Some(addr) => self.0.send_to(buf, &addr),
+            None => {
+                Err(io::const_io_error!(ErrorKind::InvalidInput, "no addresses to send data to"))
+            }
+        }
+    }
+
+    /// Returns the socket address of the remote peer this socket was connected to.
+    ///
+    /// # Examples
+    ///
+    /// ```no_run
+    /// use std::net::{Ipv4Addr, SocketAddr, SocketAddrV4, UdpSocket};
+    ///
+    /// let socket = UdpSocket::bind("127.0.0.1:34254").expect("couldn't bind to address");
+    /// socket.connect("192.168.0.1:41203").expect("couldn't connect to address");
+    /// assert_eq!(socket.peer_addr().unwrap(),
+    ///            SocketAddr::V4(SocketAddrV4::new(Ipv4Addr::new(192, 168, 0, 1), 41203)));
+    /// ```
+    ///
+    /// If the socket isn't connected, it will return a [`NotConnected`] error.
+    ///
+    /// [`NotConnected`]: io::ErrorKind::NotConnected
+    ///
+    /// ```no_run
+    /// use std::net::UdpSocket;
+    ///
+    /// let socket = UdpSocket::bind("127.0.0.1:34254").expect("couldn't bind to address");
+    /// assert_eq!(socket.peer_addr().unwrap_err().kind(),
+    ///            std::io::ErrorKind::NotConnected);
+    /// ```
+    #[stable(feature = "udp_peer_addr", since = "1.40.0")]
+    pub fn peer_addr(&self) -> io::Result<SocketAddr> {
+        self.0.peer_addr()
+    }
+
+    /// Returns the socket address that this socket was created from.
+    ///
+    /// # Examples
+    ///
+    /// ```no_run
+    /// use std::net::{Ipv4Addr, SocketAddr, SocketAddrV4, UdpSocket};
+    ///
+    /// let socket = UdpSocket::bind("127.0.0.1:34254").expect("couldn't bind to address");
+    /// assert_eq!(socket.local_addr().unwrap(),
+    ///            SocketAddr::V4(SocketAddrV4::new(Ipv4Addr::new(127, 0, 0, 1), 34254)));
+    /// ```
+    #[stable(feature = "rust1", since = "1.0.0")]
+    pub fn local_addr(&self) -> io::Result<SocketAddr> {
+        self.0.socket_addr()
+    }
+
+    /// Creates a new independently owned handle to the underlying socket.
+    ///
+    /// The returned `UdpSocket` is a reference to the same socket that this
+    /// object references. Both handles will read and write the same port, and
+    /// options set on one socket will be propagated to the other.
+    ///
+    /// # Examples
+    ///
+    /// ```no_run
+    /// use std::net::UdpSocket;
+    ///
+    /// let socket = UdpSocket::bind("127.0.0.1:34254").expect("couldn't bind to address");
+    /// let socket_clone = socket.try_clone().expect("couldn't clone the socket");
+    /// ```
+    #[stable(feature = "rust1", since = "1.0.0")]
+    pub fn try_clone(&self) -> io::Result<UdpSocket> {
+        self.0.duplicate().map(UdpSocket)
+    }
+
+    /// Sets the read timeout to the timeout specified.
+    ///
+    /// If the value specified is [`None`], then [`read`] calls will block
+    /// indefinitely. An [`Err`] is returned if the zero [`Duration`] is
+    /// passed to this method.
+    ///
+    /// # Platform-specific behavior
+    ///
+    /// Platforms may return a different error code whenever a read times out as
+    /// a result of setting this option. For example Unix typically returns an
+    /// error of the kind [`WouldBlock`], but Windows may return [`TimedOut`].
+    ///
+    /// [`read`]: io::Read::read
+    /// [`WouldBlock`]: io::ErrorKind::WouldBlock
+    /// [`TimedOut`]: io::ErrorKind::TimedOut
+    ///
+    /// # Examples
+    ///
+    /// ```no_run
+    /// use std::net::UdpSocket;
+    ///
+    /// let socket = UdpSocket::bind("127.0.0.1:34254").expect("couldn't bind to address");
+    /// socket.set_read_timeout(None).expect("set_read_timeout call failed");
+    /// ```
+    ///
+    /// An [`Err`] is returned if the zero [`Duration`] is passed to this
+    /// method:
+    ///
+    /// ```no_run
+    /// use std::io;
+    /// use std::net::UdpSocket;
+    /// use std::time::Duration;
+    ///
+    /// let socket = UdpSocket::bind("127.0.0.1:34254").unwrap();
+    /// let result = socket.set_read_timeout(Some(Duration::new(0, 0)));
+    /// let err = result.unwrap_err();
+    /// assert_eq!(err.kind(), io::ErrorKind::InvalidInput)
+    /// ```
+    #[stable(feature = "socket_timeout", since = "1.4.0")]
+    pub fn set_read_timeout(&self, dur: Option<Duration>) -> io::Result<()> {
+        self.0.set_read_timeout(dur)
+    }
+
+    /// Sets the write timeout to the timeout specified.
+    ///
+    /// If the value specified is [`None`], then [`write`] calls will block
+    /// indefinitely. An [`Err`] is returned if the zero [`Duration`] is
+    /// passed to this method.
+    ///
+    /// # Platform-specific behavior
+    ///
+    /// Platforms may return a different error code whenever a write times out
+    /// as a result of setting this option. For example Unix typically returns
+    /// an error of the kind [`WouldBlock`], but Windows may return [`TimedOut`].
+    ///
+    /// [`write`]: io::Write::write
+    /// [`WouldBlock`]: io::ErrorKind::WouldBlock
+    /// [`TimedOut`]: io::ErrorKind::TimedOut
+    ///
+    /// # Examples
+    ///
+    /// ```no_run
+    /// use std::net::UdpSocket;
+    ///
+    /// let socket = UdpSocket::bind("127.0.0.1:34254").expect("couldn't bind to address");
+    /// socket.set_write_timeout(None).expect("set_write_timeout call failed");
+    /// ```
+    ///
+    /// An [`Err`] is returned if the zero [`Duration`] is passed to this
+    /// method:
+    ///
+    /// ```no_run
+    /// use std::io;
+    /// use std::net::UdpSocket;
+    /// use std::time::Duration;
+    ///
+    /// let socket = UdpSocket::bind("127.0.0.1:34254").unwrap();
+    /// let result = socket.set_write_timeout(Some(Duration::new(0, 0)));
+    /// let err = result.unwrap_err();
+    /// assert_eq!(err.kind(), io::ErrorKind::InvalidInput)
+    /// ```
+    #[stable(feature = "socket_timeout", since = "1.4.0")]
+    pub fn set_write_timeout(&self, dur: Option<Duration>) -> io::Result<()> {
+        self.0.set_write_timeout(dur)
+    }
+
+    /// Returns the read timeout of this socket.
+    ///
+    /// If the timeout is [`None`], then [`read`] calls will block indefinitely.
+    ///
+    /// [`read`]: io::Read::read
+    ///
+    /// # Examples
+    ///
+    /// ```no_run
+    /// use std::net::UdpSocket;
+    ///
+    /// let socket = UdpSocket::bind("127.0.0.1:34254").expect("couldn't bind to address");
+    /// socket.set_read_timeout(None).expect("set_read_timeout call failed");
+    /// assert_eq!(socket.read_timeout().unwrap(), None);
+    /// ```
+    #[stable(feature = "socket_timeout", since = "1.4.0")]
+    pub fn read_timeout(&self) -> io::Result<Option<Duration>> {
+        self.0.read_timeout()
+    }
+
+    /// Returns the write timeout of this socket.
+    ///
+    /// If the timeout is [`None`], then [`write`] calls will block indefinitely.
+    ///
+    /// [`write`]: io::Write::write
+    ///
+    /// # Examples
+    ///
+    /// ```no_run
+    /// use std::net::UdpSocket;
+    ///
+    /// let socket = UdpSocket::bind("127.0.0.1:34254").expect("couldn't bind to address");
+    /// socket.set_write_timeout(None).expect("set_write_timeout call failed");
+    /// assert_eq!(socket.write_timeout().unwrap(), None);
+    /// ```
+    #[stable(feature = "socket_timeout", since = "1.4.0")]
+    pub fn write_timeout(&self) -> io::Result<Option<Duration>> {
+        self.0.write_timeout()
+    }
+
+    /// Sets the value of the `SO_BROADCAST` option for this socket.
+    ///
+    /// When enabled, this socket is allowed to send packets to a broadcast
+    /// address.
+    ///
+    /// # Examples
+    ///
+    /// ```no_run
+    /// use std::net::UdpSocket;
+    ///
+    /// let socket = UdpSocket::bind("127.0.0.1:34254").expect("couldn't bind to address");
+    /// socket.set_broadcast(false).expect("set_broadcast call failed");
+    /// ```
+    #[stable(feature = "net2_mutators", since = "1.9.0")]
+    pub fn set_broadcast(&self, broadcast: bool) -> io::Result<()> {
+        self.0.set_broadcast(broadcast)
+    }
+
+    /// Gets the value of the `SO_BROADCAST` option for this socket.
+    ///
+    /// For more information about this option, see [`UdpSocket::set_broadcast`].
+    ///
+    /// # Examples
+    ///
+    /// ```no_run
+    /// use std::net::UdpSocket;
+    ///
+    /// let socket = UdpSocket::bind("127.0.0.1:34254").expect("couldn't bind to address");
+    /// socket.set_broadcast(false).expect("set_broadcast call failed");
+    /// assert_eq!(socket.broadcast().unwrap(), false);
+    /// ```
+    #[stable(feature = "net2_mutators", since = "1.9.0")]
+    pub fn broadcast(&self) -> io::Result<bool> {
+        self.0.broadcast()
+    }
+
+    /// Sets the value of the `IP_MULTICAST_LOOP` option for this socket.
+    ///
+    /// If enabled, multicast packets will be looped back to the local socket.
+    /// Note that this might not have any effect on IPv6 sockets.
+    ///
+    /// # Examples
+    ///
+    /// ```no_run
+    /// use std::net::UdpSocket;
+    ///
+    /// let socket = UdpSocket::bind("127.0.0.1:34254").expect("couldn't bind to address");
+    /// socket.set_multicast_loop_v4(false).expect("set_multicast_loop_v4 call failed");
+    /// ```
+    #[stable(feature = "net2_mutators", since = "1.9.0")]
+    pub fn set_multicast_loop_v4(&self, multicast_loop_v4: bool) -> io::Result<()> {
+        self.0.set_multicast_loop_v4(multicast_loop_v4)
+    }
+
+    /// Gets the value of the `IP_MULTICAST_LOOP` option for this socket.
+    ///
+    /// For more information about this option, see [`UdpSocket::set_multicast_loop_v4`].
+    ///
+    /// # Examples
+    ///
+    /// ```no_run
+    /// use std::net::UdpSocket;
+    ///
+    /// let socket = UdpSocket::bind("127.0.0.1:34254").expect("couldn't bind to address");
+    /// socket.set_multicast_loop_v4(false).expect("set_multicast_loop_v4 call failed");
+    /// assert_eq!(socket.multicast_loop_v4().unwrap(), false);
+    /// ```
+    #[stable(feature = "net2_mutators", since = "1.9.0")]
+    pub fn multicast_loop_v4(&self) -> io::Result<bool> {
+        self.0.multicast_loop_v4()
+    }
+
+    /// Sets the value of the `IP_MULTICAST_TTL` option for this socket.
+    ///
+    /// Indicates the time-to-live value of outgoing multicast packets for
+    /// this socket. The default value is 1 which means that multicast packets
+    /// don't leave the local network unless explicitly requested.
+    ///
+    /// Note that this might not have any effect on IPv6 sockets.
+    ///
+    /// # Examples
+    ///
+    /// ```no_run
+    /// use std::net::UdpSocket;
+    ///
+    /// let socket = UdpSocket::bind("127.0.0.1:34254").expect("couldn't bind to address");
+    /// socket.set_multicast_ttl_v4(42).expect("set_multicast_ttl_v4 call failed");
+    /// ```
+    #[stable(feature = "net2_mutators", since = "1.9.0")]
+    pub fn set_multicast_ttl_v4(&self, multicast_ttl_v4: u32) -> io::Result<()> {
+        self.0.set_multicast_ttl_v4(multicast_ttl_v4)
+    }
+
+    /// Gets the value of the `IP_MULTICAST_TTL` option for this socket.
+    ///
+    /// For more information about this option, see [`UdpSocket::set_multicast_ttl_v4`].
+    ///
+    /// # Examples
+    ///
+    /// ```no_run
+    /// use std::net::UdpSocket;
+    ///
+    /// let socket = UdpSocket::bind("127.0.0.1:34254").expect("couldn't bind to address");
+    /// socket.set_multicast_ttl_v4(42).expect("set_multicast_ttl_v4 call failed");
+    /// assert_eq!(socket.multicast_ttl_v4().unwrap(), 42);
+    /// ```
+    #[stable(feature = "net2_mutators", since = "1.9.0")]
+    pub fn multicast_ttl_v4(&self) -> io::Result<u32> {
+        self.0.multicast_ttl_v4()
+    }
+
+    /// Sets the value of the `IPV6_MULTICAST_LOOP` option for this socket.
+    ///
+    /// Controls whether this socket sees the multicast packets it sends itself.
+    /// Note that this might not have any affect on IPv4 sockets.
+    ///
+    /// # Examples
+    ///
+    /// ```no_run
+    /// use std::net::UdpSocket;
+    ///
+    /// let socket = UdpSocket::bind("127.0.0.1:34254").expect("couldn't bind to address");
+    /// socket.set_multicast_loop_v6(false).expect("set_multicast_loop_v6 call failed");
+    /// ```
+    #[stable(feature = "net2_mutators", since = "1.9.0")]
+    pub fn set_multicast_loop_v6(&self, multicast_loop_v6: bool) -> io::Result<()> {
+        self.0.set_multicast_loop_v6(multicast_loop_v6)
+    }
+
+    /// Gets the value of the `IPV6_MULTICAST_LOOP` option for this socket.
+    ///
+    /// For more information about this option, see [`UdpSocket::set_multicast_loop_v6`].
+    ///
+    /// # Examples
+    ///
+    /// ```no_run
+    /// use std::net::UdpSocket;
+    ///
+    /// let socket = UdpSocket::bind("127.0.0.1:34254").expect("couldn't bind to address");
+    /// socket.set_multicast_loop_v6(false).expect("set_multicast_loop_v6 call failed");
+    /// assert_eq!(socket.multicast_loop_v6().unwrap(), false);
+    /// ```
+    #[stable(feature = "net2_mutators", since = "1.9.0")]
+    pub fn multicast_loop_v6(&self) -> io::Result<bool> {
+        self.0.multicast_loop_v6()
+    }
+
+    /// Sets the value for the `IP_TTL` option on this socket.
+    ///
+    /// This value sets the time-to-live field that is used in every packet sent
+    /// from this socket.
+    ///
+    /// # Examples
+    ///
+    /// ```no_run
+    /// use std::net::UdpSocket;
+    ///
+    /// let socket = UdpSocket::bind("127.0.0.1:34254").expect("couldn't bind to address");
+    /// socket.set_ttl(42).expect("set_ttl call failed");
+    /// ```
+    #[stable(feature = "net2_mutators", since = "1.9.0")]
+    pub fn set_ttl(&self, ttl: u32) -> io::Result<()> {
+        self.0.set_ttl(ttl)
+    }
+
+    /// Gets the value of the `IP_TTL` option for this socket.
+    ///
+    /// For more information about this option, see [`UdpSocket::set_ttl`].
+    ///
+    /// # Examples
+    ///
+    /// ```no_run
+    /// use std::net::UdpSocket;
+    ///
+    /// let socket = UdpSocket::bind("127.0.0.1:34254").expect("couldn't bind to address");
+    /// socket.set_ttl(42).expect("set_ttl call failed");
+    /// assert_eq!(socket.ttl().unwrap(), 42);
+    /// ```
+    #[stable(feature = "net2_mutators", since = "1.9.0")]
+    pub fn ttl(&self) -> io::Result<u32> {
+        self.0.ttl()
+    }
+
+    /// Executes an operation of the `IP_ADD_MEMBERSHIP` type.
+    ///
+    /// This function specifies a new multicast group for this socket to join.
+    /// The address must be a valid multicast address, and `interface` is the
+    /// address of the local interface with which the system should join the
+    /// multicast group. If it's equal to `INADDR_ANY` then an appropriate
+    /// interface is chosen by the system.
+    #[stable(feature = "net2_mutators", since = "1.9.0")]
+    pub fn join_multicast_v4(&self, multiaddr: &Ipv4Addr, interface: &Ipv4Addr) -> io::Result<()> {
+        self.0.join_multicast_v4(multiaddr, interface)
+    }
+
+    /// Executes an operation of the `IPV6_ADD_MEMBERSHIP` type.
+    ///
+    /// This function specifies a new multicast group for this socket to join.
+    /// The address must be a valid multicast address, and `interface` is the
+    /// index of the interface to join/leave (or 0 to indicate any interface).
+    #[stable(feature = "net2_mutators", since = "1.9.0")]
+    pub fn join_multicast_v6(&self, multiaddr: &Ipv6Addr, interface: u32) -> io::Result<()> {
+        self.0.join_multicast_v6(multiaddr, interface)
+    }
+
+    /// Executes an operation of the `IP_DROP_MEMBERSHIP` type.
+    ///
+    /// For more information about this option, see [`UdpSocket::join_multicast_v4`].
+    #[stable(feature = "net2_mutators", since = "1.9.0")]
+    pub fn leave_multicast_v4(&self, multiaddr: &Ipv4Addr, interface: &Ipv4Addr) -> io::Result<()> {
+        self.0.leave_multicast_v4(multiaddr, interface)
+    }
+
+    /// Executes an operation of the `IPV6_DROP_MEMBERSHIP` type.
+    ///
+    /// For more information about this option, see [`UdpSocket::join_multicast_v6`].
+    #[stable(feature = "net2_mutators", since = "1.9.0")]
+    pub fn leave_multicast_v6(&self, multiaddr: &Ipv6Addr, interface: u32) -> io::Result<()> {
+        self.0.leave_multicast_v6(multiaddr, interface)
+    }
+
+    /// Gets the value of the `SO_ERROR` option on this socket.
+    ///
+    /// This will retrieve the stored error in the underlying socket, clearing
+    /// the field in the process. This can be useful for checking errors between
+    /// calls.
+    ///
+    /// # Examples
+    ///
+    /// ```no_run
+    /// use std::net::UdpSocket;
+    ///
+    /// let socket = UdpSocket::bind("127.0.0.1:34254").expect("couldn't bind to address");
+    /// match socket.take_error() {
+    ///     Ok(Some(error)) => println!("UdpSocket error: {error:?}"),
+    ///     Ok(None) => println!("No error"),
+    ///     Err(error) => println!("UdpSocket.take_error failed: {error:?}"),
+    /// }
+    /// ```
+    #[stable(feature = "net2_mutators", since = "1.9.0")]
+    pub fn take_error(&self) -> io::Result<Option<io::Error>> {
+        self.0.take_error()
+    }
+
+    /// Connects this UDP socket to a remote address, allowing the `send` and
+    /// `recv` syscalls to be used to send data and also applies filters to only
+    /// receive data from the specified address.
+    ///
+    /// If `addr` yields multiple addresses, `connect` will be attempted with
+    /// each of the addresses until the underlying OS function returns no
+    /// error. Note that usually, a successful `connect` call does not specify
+    /// that there is a remote server listening on the port, rather, such an
+    /// error would only be detected after the first send. If the OS returns an
+    /// error for each of the specified addresses, the error returned from the
+    /// last connection attempt (the last address) is returned.
+    ///
+    /// # Examples
+    ///
+    /// Creates a UDP socket bound to `127.0.0.1:3400` and connect the socket to
+    /// `127.0.0.1:8080`:
+    ///
+    /// ```no_run
+    /// use std::net::UdpSocket;
+    ///
+    /// let socket = UdpSocket::bind("127.0.0.1:3400").expect("couldn't bind to address");
+    /// socket.connect("127.0.0.1:8080").expect("connect function failed");
+    /// ```
+    ///
+    /// Unlike in the TCP case, passing an array of addresses to the `connect`
+    /// function of a UDP socket is not a useful thing to do: The OS will be
+    /// unable to determine whether something is listening on the remote
+    /// address without the application sending data.
+    #[stable(feature = "net2_mutators", since = "1.9.0")]
+    pub fn connect<A: ToSocketAddrs>(&self, addr: A) -> io::Result<()> {
+        super::each_addr(addr, |addr| self.0.connect(addr))
+    }
+
+    /// Sends data on the socket to the remote address to which it is connected.
+    ///
+    /// [`UdpSocket::connect`] will connect this socket to a remote address. This
+    /// method will fail if the socket is not connected.
+    ///
+    /// # Examples
+    ///
+    /// ```no_run
+    /// use std::net::UdpSocket;
+    ///
+    /// let socket = UdpSocket::bind("127.0.0.1:34254").expect("couldn't bind to address");
+    /// socket.connect("127.0.0.1:8080").expect("connect function failed");
+    /// socket.send(&[0, 1, 2]).expect("couldn't send message");
+    /// ```
+    #[stable(feature = "net2_mutators", since = "1.9.0")]
+    pub fn send(&self, buf: &[u8]) -> io::Result<usize> {
+        self.0.send(buf)
+    }
+
+    /// Receives a single datagram message on the socket from the remote address to
+    /// which it is connected. On success, returns the number of bytes read.
+    ///
+    /// The function must be called with valid byte array `buf` of sufficient size to
+    /// hold the message bytes. If a message is too long to fit in the supplied buffer,
+    /// excess bytes may be discarded.
+    ///
+    /// [`UdpSocket::connect`] will connect this socket to a remote address. This
+    /// method will fail if the socket is not connected.
+    ///
+    /// # Examples
+    ///
+    /// ```no_run
+    /// use std::net::UdpSocket;
+    ///
+    /// let socket = UdpSocket::bind("127.0.0.1:34254").expect("couldn't bind to address");
+    /// socket.connect("127.0.0.1:8080").expect("connect function failed");
+    /// let mut buf = [0; 10];
+    /// match socket.recv(&mut buf) {
+    ///     Ok(received) => println!("received {received} bytes {:?}", &buf[..received]),
+    ///     Err(e) => println!("recv function failed: {e:?}"),
+    /// }
+    /// ```
+    #[stable(feature = "net2_mutators", since = "1.9.0")]
+    pub fn recv(&self, buf: &mut [u8]) -> io::Result<usize> {
+        self.0.recv(buf)
+    }
+
+    /// Receives single datagram on the socket from the remote address to which it is
+    /// connected, without removing the message from input queue. On success, returns
+    /// the number of bytes peeked.
+    ///
+    /// The function must be called with valid byte array `buf` of sufficient size to
+    /// hold the message bytes. If a message is too long to fit in the supplied buffer,
+    /// excess bytes may be discarded.
+    ///
+    /// Successive calls return the same data. This is accomplished by passing
+    /// `MSG_PEEK` as a flag to the underlying `recv` system call.
+    ///
+    /// Do not use this function to implement busy waiting, instead use `libc::poll` to
+    /// synchronize IO events on one or more sockets.
+    ///
+    /// [`UdpSocket::connect`] will connect this socket to a remote address. This
+    /// method will fail if the socket is not connected.
+    ///
+    /// # Errors
+    ///
+    /// This method will fail if the socket is not connected. The `connect` method
+    /// will connect this socket to a remote address.
+    ///
+    /// # Examples
+    ///
+    /// ```no_run
+    /// use std::net::UdpSocket;
+    ///
+    /// let socket = UdpSocket::bind("127.0.0.1:34254").expect("couldn't bind to address");
+    /// socket.connect("127.0.0.1:8080").expect("connect function failed");
+    /// let mut buf = [0; 10];
+    /// match socket.peek(&mut buf) {
+    ///     Ok(received) => println!("received {received} bytes"),
+    ///     Err(e) => println!("peek function failed: {e:?}"),
+    /// }
+    /// ```
+    #[stable(feature = "peek", since = "1.18.0")]
+    pub fn peek(&self, buf: &mut [u8]) -> io::Result<usize> {
+        self.0.peek(buf)
+    }
+
+    /// Moves this UDP socket into or out of nonblocking mode.
+    ///
+    /// This will result in `recv`, `recv_from`, `send`, and `send_to`
+    /// operations becoming nonblocking, i.e., immediately returning from their
+    /// calls. If the IO operation is successful, `Ok` is returned and no
+    /// further action is required. If the IO operation could not be completed
+    /// and needs to be retried, an error with kind
+    /// [`io::ErrorKind::WouldBlock`] is returned.
+    ///
+    /// On Unix platforms, calling this method corresponds to calling `fcntl`
+    /// `FIONBIO`. On Windows calling this method corresponds to calling
+    /// `ioctlsocket` `FIONBIO`.
+    ///
+    /// # Examples
+    ///
+    /// Creates a UDP socket bound to `127.0.0.1:7878` and read bytes in
+    /// nonblocking mode:
+    ///
+    /// ```no_run
+    /// use std::io;
+    /// use std::net::UdpSocket;
+    ///
+    /// let socket = UdpSocket::bind("127.0.0.1:7878").unwrap();
+    /// socket.set_nonblocking(true).unwrap();
+    ///
+    /// # fn wait_for_fd() { unimplemented!() }
+    /// let mut buf = [0; 10];
+    /// let (num_bytes_read, _) = loop {
+    ///     match socket.recv_from(&mut buf) {
+    ///         Ok(n) => break n,
+    ///         Err(ref e) if e.kind() == io::ErrorKind::WouldBlock => {
+    ///             // wait until network socket is ready, typically implemented
+    ///             // via platform-specific APIs such as epoll or IOCP
+    ///             wait_for_fd();
+    ///         }
+    ///         Err(e) => panic!("encountered IO error: {e}"),
+    ///     }
+    /// };
+    /// println!("bytes: {:?}", &buf[..num_bytes_read]);
+    /// ```
+    #[stable(feature = "net2_mutators", since = "1.9.0")]
+    pub fn set_nonblocking(&self, nonblocking: bool) -> io::Result<()> {
+        self.0.set_nonblocking(nonblocking)
+    }
+}
+
+// In addition to the `impl`s here, `UdpSocket` also has `impl`s for
+// `AsFd`/`From<OwnedFd>`/`Into<OwnedFd>` and
+// `AsRawFd`/`IntoRawFd`/`FromRawFd`, on Unix and WASI, and
+// `AsSocket`/`From<OwnedSocket>`/`Into<OwnedSocket>` and
+// `AsRawSocket`/`IntoRawSocket`/`FromRawSocket` on Windows.
+
+impl AsInner<net_imp::UdpSocket> for UdpSocket {
+    fn as_inner(&self) -> &net_imp::UdpSocket {
+        &self.0
+    }
+}
+
+impl FromInner<net_imp::UdpSocket> for UdpSocket {
+    fn from_inner(inner: net_imp::UdpSocket) -> UdpSocket {
+        UdpSocket(inner)
+    }
+}
+
+impl IntoInner<net_imp::UdpSocket> for UdpSocket {
+    fn into_inner(self) -> net_imp::UdpSocket {
+        self.0
+    }
+}
+
+#[stable(feature = "rust1", since = "1.0.0")]
+impl fmt::Debug for UdpSocket {
+    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
+        self.0.fmt(f)
+    }
+}
diff --git a/library/std/src/net/udp/tests.rs b/library/std/src/net/udp/tests.rs
new file mode 100644
index 000000000..f82904ffb
--- /dev/null
+++ b/library/std/src/net/udp/tests.rs
@@ -0,0 +1,365 @@
+use crate::io::ErrorKind;
+use crate::net::test::{next_test_ip4, next_test_ip6};
+use crate::net::*;
+use crate::sync::mpsc::channel;
+use crate::thread;
+use crate::time::{Duration, Instant};
+
+fn each_ip(f: &mut dyn FnMut(SocketAddr, SocketAddr)) {
+    f(next_test_ip4(), next_test_ip4());
+    f(next_test_ip6(), next_test_ip6());
+}
+
+macro_rules! t {
+    ($e:expr) => {
+        match $e {
+            Ok(t) => t,
+            Err(e) => panic!("received error for `{}`: {}", stringify!($e), e),
+        }
+    };
+}
+
+#[test]
+fn bind_error() {
+    match UdpSocket::bind("1.1.1.1:9999") {
+        Ok(..) => panic!(),
+        Err(e) => assert_eq!(e.kind(), ErrorKind::AddrNotAvailable),
+    }
+}
+
+#[test]
+fn socket_smoke_test_ip4() {
+    each_ip(&mut |server_ip, client_ip| {
+        let (tx1, rx1) = channel();
+        let (tx2, rx2) = channel();
+
+        let _t = thread::spawn(move || {
+            let client = t!(UdpSocket::bind(&client_ip));
+            rx1.recv().unwrap();
+            t!(client.send_to(&[99], &server_ip));
+            tx2.send(()).unwrap();
+        });
+
+        let server = t!(UdpSocket::bind(&server_ip));
+        tx1.send(()).unwrap();
+        let mut buf = [0];
+        let (nread, src) = t!(server.recv_from(&mut buf));
+        assert_eq!(nread, 1);
+        assert_eq!(buf[0], 99);
+        assert_eq!(src, client_ip);
+        rx2.recv().unwrap();
+    })
+}
+
+#[test]
+fn socket_name() {
+    each_ip(&mut |addr, _| {
+        let server = t!(UdpSocket::bind(&addr));
+        assert_eq!(addr, t!(server.local_addr()));
+    })
+}
+
+#[test]
+fn socket_peer() {
+    each_ip(&mut |addr1, addr2| {
+        let server = t!(UdpSocket::bind(&addr1));
+        assert_eq!(server.peer_addr().unwrap_err().kind(), ErrorKind::NotConnected);
+        t!(server.connect(&addr2));
+        assert_eq!(addr2, t!(server.peer_addr()));
+    })
+}
+
+#[test]
+fn udp_clone_smoke() {
+    each_ip(&mut |addr1, addr2| {
+        let sock1 = t!(UdpSocket::bind(&addr1));
+        let sock2 = t!(UdpSocket::bind(&addr2));
+
+        let _t = thread::spawn(move || {
+            let mut buf = [0, 0];
+            assert_eq!(sock2.recv_from(&mut buf).unwrap(), (1, addr1));
+            assert_eq!(buf[0], 1);
+            t!(sock2.send_to(&[2], &addr1));
+        });
+
+        let sock3 = t!(sock1.try_clone());
+
+        let (tx1, rx1) = channel();
+        let (tx2, rx2) = channel();
+        let _t = thread::spawn(move || {
+            rx1.recv().unwrap();
+            t!(sock3.send_to(&[1], &addr2));
+            tx2.send(()).unwrap();
+        });
+        tx1.send(()).unwrap();
+        let mut buf = [0, 0];
+        assert_eq!(sock1.recv_from(&mut buf).unwrap(), (1, addr2));
+        rx2.recv().unwrap();
+    })
+}
+
+#[test]
+fn udp_clone_two_read() {
+    each_ip(&mut |addr1, addr2| {
+        let sock1 = t!(UdpSocket::bind(&addr1));
+        let sock2 = t!(UdpSocket::bind(&addr2));
+        let (tx1, rx) = channel();
+        let tx2 = tx1.clone();
+
+        let _t = thread::spawn(move || {
+            t!(sock2.send_to(&[1], &addr1));
+            rx.recv().unwrap();
+            t!(sock2.send_to(&[2], &addr1));
+            rx.recv().unwrap();
+        });
+
+        let sock3 = t!(sock1.try_clone());
+
+        let (done, rx) = channel();
+        let _t = thread::spawn(move || {
+            let mut buf = [0, 0];
+            t!(sock3.recv_from(&mut buf));
+            tx2.send(()).unwrap();
+            done.send(()).unwrap();
+        });
+        let mut buf = [0, 0];
+        t!(sock1.recv_from(&mut buf));
+        tx1.send(()).unwrap();
+
+        rx.recv().unwrap();
+    })
+}
+
+#[test]
+fn udp_clone_two_write() {
+    each_ip(&mut |addr1, addr2| {
+        let sock1 = t!(UdpSocket::bind(&addr1));
+        let sock2 = t!(UdpSocket::bind(&addr2));
+
+        let (tx, rx) = channel();
+        let (serv_tx, serv_rx) = channel();
+
+        let _t = thread::spawn(move || {
+            let mut buf = [0, 1];
+            rx.recv().unwrap();
+            t!(sock2.recv_from(&mut buf));
+            serv_tx.send(()).unwrap();
+        });
+
+        let sock3 = t!(sock1.try_clone());
+
+        let (done, rx) = channel();
+        let tx2 = tx.clone();
+        let _t = thread::spawn(move || {
+            if sock3.send_to(&[1], &addr2).is_ok() {
+                let _ = tx2.send(());
+            }
+            done.send(()).unwrap();
+        });
+        if sock1.send_to(&[2], &addr2).is_ok() {
+            let _ = tx.send(());
+        }
+        drop(tx);
+
+        rx.recv().unwrap();
+        serv_rx.recv().unwrap();
+    })
+}
+
+#[test]
+fn debug() {
+    let name = if cfg!(windows) { "socket" } else { "fd" };
+    let socket_addr = next_test_ip4();
+
+    let udpsock = t!(UdpSocket::bind(&socket_addr));
+    let udpsock_inner = udpsock.0.socket().as_raw();
+    let compare = format!("UdpSocket {{ addr: {socket_addr:?}, {name}: {udpsock_inner:?} }}");
+    assert_eq!(format!("{udpsock:?}"), compare);
+}
+
+// FIXME: re-enabled openbsd/netbsd tests once their socket timeout code
+//        no longer has rounding errors.
+// VxWorks ignores SO_SNDTIMEO.
+#[cfg_attr(any(target_os = "netbsd", target_os = "openbsd", target_os = "vxworks"), ignore)]
+#[test]
+fn timeouts() {
+    let addr = next_test_ip4();
+
+    let stream = t!(UdpSocket::bind(&addr));
+    let dur = Duration::new(15410, 0);
+
+    assert_eq!(None, t!(stream.read_timeout()));
+
+    t!(stream.set_read_timeout(Some(dur)));
+    assert_eq!(Some(dur), t!(stream.read_timeout()));
+
+    assert_eq!(None, t!(stream.write_timeout()));
+
+    t!(stream.set_write_timeout(Some(dur)));
+    assert_eq!(Some(dur), t!(stream.write_timeout()));
+
+    t!(stream.set_read_timeout(None));
+    assert_eq!(None, t!(stream.read_timeout()));
+
+    t!(stream.set_write_timeout(None));
+    assert_eq!(None, t!(stream.write_timeout()));
+}
+
+#[test]
+fn test_read_timeout() {
+    let addr = next_test_ip4();
+
+    let stream = t!(UdpSocket::bind(&addr));
+    t!(stream.set_read_timeout(Some(Duration::from_millis(1000))));
+
+    let mut buf = [0; 10];
+
+    let start = Instant::now();
+    loop {
+        let kind = stream.recv_from(&mut buf).err().expect("expected error").kind();
+        if kind != ErrorKind::Interrupted {
+            assert!(
+                kind == ErrorKind::WouldBlock || kind == ErrorKind::TimedOut,
+                "unexpected_error: {:?}",
+                kind
+            );
+            break;
+        }
+    }
+    assert!(start.elapsed() > Duration::from_millis(400));
+}
+
+#[test]
+fn test_read_with_timeout() {
+    let addr = next_test_ip4();
+
+    let stream = t!(UdpSocket::bind(&addr));
+    t!(stream.set_read_timeout(Some(Duration::from_millis(1000))));
+
+    t!(stream.send_to(b"hello world", &addr));
+
+    let mut buf = [0; 11];
+    t!(stream.recv_from(&mut buf));
+    assert_eq!(b"hello world", &buf[..]);
+
+    let start = Instant::now();
+    loop {
+        let kind = stream.recv_from(&mut buf).err().expect("expected error").kind();
+        if kind != ErrorKind::Interrupted {
+            assert!(
+                kind == ErrorKind::WouldBlock || kind == ErrorKind::TimedOut,
+                "unexpected_error: {:?}",
+                kind
+            );
+            break;
+        }
+    }
+    assert!(start.elapsed() > Duration::from_millis(400));
+}
+
+// Ensure the `set_read_timeout` and `set_write_timeout` calls return errors
+// when passed zero Durations
+#[test]
+fn test_timeout_zero_duration() {
+    let addr = next_test_ip4();
+
+    let socket = t!(UdpSocket::bind(&addr));
+
+    let result = socket.set_write_timeout(Some(Duration::new(0, 0)));
+    let err = result.unwrap_err();
+    assert_eq!(err.kind(), ErrorKind::InvalidInput);
+
+    let result = socket.set_read_timeout(Some(Duration::new(0, 0)));
+    let err = result.unwrap_err();
+    assert_eq!(err.kind(), ErrorKind::InvalidInput);
+}
+
+#[test]
+fn connect_send_recv() {
+    let addr = next_test_ip4();
+
+    let socket = t!(UdpSocket::bind(&addr));
+    t!(socket.connect(addr));
+
+    t!(socket.send(b"hello world"));
+
+    let mut buf = [0; 11];
+    t!(socket.recv(&mut buf));
+    assert_eq!(b"hello world", &buf[..]);
+}
+
+#[test]
+fn connect_send_peek_recv() {
+    each_ip(&mut |addr, _| {
+        let socket = t!(UdpSocket::bind(&addr));
+        t!(socket.connect(addr));
+
+        t!(socket.send(b"hello world"));
+
+        for _ in 1..3 {
+            let mut buf = [0; 11];
+            let size = t!(socket.peek(&mut buf));
+            assert_eq!(b"hello world", &buf[..]);
+            assert_eq!(size, 11);
+        }
+
+        let mut buf = [0; 11];
+        let size = t!(socket.recv(&mut buf));
+        assert_eq!(b"hello world", &buf[..]);
+        assert_eq!(size, 11);
+    })
+}
+
+#[test]
+fn peek_from() {
+    each_ip(&mut |addr, _| {
+        let socket = t!(UdpSocket::bind(&addr));
+        t!(socket.send_to(b"hello world", &addr));
+
+        for _ in 1..3 {
+            let mut buf = [0; 11];
+            let (size, _) = t!(socket.peek_from(&mut buf));
+            assert_eq!(b"hello world", &buf[..]);
+            assert_eq!(size, 11);
+        }
+
+        let mut buf = [0; 11];
+        let (size, _) = t!(socket.recv_from(&mut buf));
+        assert_eq!(b"hello world", &buf[..]);
+        assert_eq!(size, 11);
+    })
+}
+
+#[test]
+fn ttl() {
+    let ttl = 100;
+
+    let addr = next_test_ip4();
+
+    let stream = t!(UdpSocket::bind(&addr));
+
+    t!(stream.set_ttl(ttl));
+    assert_eq!(ttl, t!(stream.ttl()));
+}
+
+#[test]
+fn set_nonblocking() {
+    each_ip(&mut |addr, _| {
+        let socket = t!(UdpSocket::bind(&addr));
+
+        t!(socket.set_nonblocking(true));
+        t!(socket.set_nonblocking(false));
+
+        t!(socket.connect(addr));
+
+        t!(socket.set_nonblocking(false));
+        t!(socket.set_nonblocking(true));
+
+        let mut buf = [0];
+        match socket.recv(&mut buf) {
+            Ok(_) => panic!("expected error"),
+            Err(ref e) if e.kind() == ErrorKind::WouldBlock => {}
+            Err(e) => panic!("unexpected error {e}"),
+        }
+    })
+}