Initial vendor packages

Signed-off-by: Valentin Popov <valentin@popov.link>

1 files changed, 1065 insertions, 0 deletions

diff --git a/vendor/rustix/src/backend/libc/net/sockopt.rs b/vendor/rustix/src/backend/libc/net/sockopt.rs
new file mode 100644
index 0000000..cff2ca2
--- /dev/null
+++ b/vendor/rustix/src/backend/libc/net/sockopt.rs
@@ -0,0 +1,1065 @@
+//! libc syscalls supporting `rustix::net::sockopt`.
+
+use super::ext::{in6_addr_new, in_addr_new};
+use crate::backend::c;
+use crate::backend::conv::{borrowed_fd, ret};
+use crate::fd::BorrowedFd;
+#[cfg(feature = "alloc")]
+#[cfg(any(
+    linux_like,
+    target_os = "freebsd",
+    target_os = "fuchsia",
+    target_os = "illumos"
+))]
+use crate::ffi::CStr;
+use crate::io;
+use crate::net::sockopt::Timeout;
+#[cfg(not(any(
+    apple,
+    windows,
+    target_os = "aix",
+    target_os = "dragonfly",
+    target_os = "emscripten",
+    target_os = "espidf",
+    target_os = "haiku",
+    target_os = "netbsd",
+    target_os = "nto",
+    target_os = "vita",
+)))]
+use crate::net::AddressFamily;
+#[cfg(any(
+    linux_kernel,
+    target_os = "freebsd",
+    target_os = "fuchsia",
+    target_os = "openbsd",
+    target_os = "redox",
+    target_env = "newlib"
+))]
+use crate::net::Protocol;
+#[cfg(any(
+    linux_kernel,
+    target_os = "freebsd",
+    target_os = "fuchsia",
+    target_os = "openbsd",
+    target_os = "redox",
+    target_env = "newlib"
+))]
+use crate::net::RawProtocol;
+use crate::net::{Ipv4Addr, Ipv6Addr, SocketType};
+#[cfg(any(linux_kernel, target_os = "fuchsia"))]
+use crate::net::{SocketAddrAny, SocketAddrStorage, SocketAddrV4};
+#[cfg(linux_kernel)]
+use crate::net::{SocketAddrV6, UCred};
+use crate::utils::as_mut_ptr;
+#[cfg(feature = "alloc")]
+#[cfg(any(
+    linux_like,
+    target_os = "freebsd",
+    target_os = "fuchsia",
+    target_os = "illumos"
+))]
+use alloc::borrow::ToOwned;
+#[cfg(feature = "alloc")]
+#[cfg(any(
+    linux_like,
+    target_os = "freebsd",
+    target_os = "fuchsia",
+    target_os = "illumos"
+))]
+use alloc::string::String;
+#[cfg(apple)]
+use c::TCP_KEEPALIVE as TCP_KEEPIDLE;
+#[cfg(not(any(apple, target_os = "openbsd", target_os = "haiku", target_os = "nto")))]
+use c::TCP_KEEPIDLE;
+use core::mem::{size_of, MaybeUninit};
+use core::time::Duration;
+#[cfg(windows)]
+use windows_sys::Win32::Foundation::BOOL;
+
+#[inline]
+fn getsockopt<T: Copy>(fd: BorrowedFd<'_>, level: i32, optname: i32) -> io::Result<T> {
+    let mut optlen = core::mem::size_of::<T>().try_into().unwrap();
+    debug_assert!(
+        optlen as usize >= core::mem::size_of::<c::c_int>(),
+        "Socket APIs don't ever use `bool` directly"
+    );
+
+    let mut value = MaybeUninit::<T>::zeroed();
+    getsockopt_raw(fd, level, optname, &mut value, &mut optlen)?;
+
+    // On Windows at least, `getsockopt` has been observed writing 1
+    // byte on at least (`IPPROTO_TCP`, `TCP_NODELAY`), even though
+    // Windows' documentation says that should write a 4-byte `BOOL`.
+    // So, we initialize the memory to zeros above, and just assert
+    // that `getsockopt` doesn't write too many bytes here.
+    assert!(
+        optlen as usize <= size_of::<T>(),
+        "unexpected getsockopt size"
+    );
+
+    unsafe { Ok(value.assume_init()) }
+}
+
+#[inline]
+fn getsockopt_raw<T>(
+    fd: BorrowedFd<'_>,
+    level: i32,
+    optname: i32,
+    value: &mut MaybeUninit<T>,
+    optlen: &mut c::socklen_t,
+) -> io::Result<()> {
+    unsafe {
+        ret(c::getsockopt(
+            borrowed_fd(fd),
+            level,
+            optname,
+            as_mut_ptr(value).cast(),
+            optlen,
+        ))
+    }
+}
+
+#[inline]
+fn setsockopt<T: Copy>(fd: BorrowedFd<'_>, level: i32, optname: i32, value: T) -> io::Result<()> {
+    let optlen = core::mem::size_of::<T>().try_into().unwrap();
+    debug_assert!(
+        optlen as usize >= core::mem::size_of::<c::c_int>(),
+        "Socket APIs don't ever use `bool` directly"
+    );
+    setsockopt_raw(fd, level, optname, &value, optlen)
+}
+
+#[inline]
+fn setsockopt_raw<T>(
+    fd: BorrowedFd<'_>,
+    level: i32,
+    optname: i32,
+    ptr: *const T,
+    optlen: c::socklen_t,
+) -> io::Result<()> {
+    unsafe {
+        ret(c::setsockopt(
+            borrowed_fd(fd),
+            level,
+            optname,
+            ptr.cast(),
+            optlen,
+        ))
+    }
+}
+
+#[inline]
+pub(crate) fn get_socket_type(fd: BorrowedFd<'_>) -> io::Result<SocketType> {
+    getsockopt(fd, c::SOL_SOCKET, c::SO_TYPE)
+}
+
+#[inline]
+pub(crate) fn set_socket_reuseaddr(fd: BorrowedFd<'_>, reuseaddr: bool) -> io::Result<()> {
+    setsockopt(fd, c::SOL_SOCKET, c::SO_REUSEADDR, from_bool(reuseaddr))
+}
+
+#[inline]
+pub(crate) fn get_socket_reuseaddr(fd: BorrowedFd<'_>) -> io::Result<bool> {
+    getsockopt(fd, c::SOL_SOCKET, c::SO_REUSEADDR).map(to_bool)
+}
+
+#[inline]
+pub(crate) fn set_socket_broadcast(fd: BorrowedFd<'_>, broadcast: bool) -> io::Result<()> {
+    setsockopt(fd, c::SOL_SOCKET, c::SO_BROADCAST, from_bool(broadcast))
+}
+
+#[inline]
+pub(crate) fn get_socket_broadcast(fd: BorrowedFd<'_>) -> io::Result<bool> {
+    getsockopt(fd, c::SOL_SOCKET, c::SO_BROADCAST).map(to_bool)
+}
+
+#[inline]
+pub(crate) fn set_socket_linger(fd: BorrowedFd<'_>, linger: Option<Duration>) -> io::Result<()> {
+    // Convert `linger` to seconds, rounding up.
+    let l_linger = if let Some(linger) = linger {
+        duration_to_secs(linger)?
+    } else {
+        0
+    };
+    let linger = c::linger {
+        l_onoff: linger.is_some().into(),
+        l_linger,
+    };
+    setsockopt(fd, c::SOL_SOCKET, c::SO_LINGER, linger)
+}
+
+#[inline]
+pub(crate) fn get_socket_linger(fd: BorrowedFd<'_>) -> io::Result<Option<Duration>> {
+    let linger: c::linger = getsockopt(fd, c::SOL_SOCKET, c::SO_LINGER)?;
+    Ok((linger.l_onoff != 0).then(|| Duration::from_secs(linger.l_linger as u64)))
+}
+
+#[cfg(linux_kernel)]
+#[inline]
+pub(crate) fn set_socket_passcred(fd: BorrowedFd<'_>, passcred: bool) -> io::Result<()> {
+    setsockopt(fd, c::SOL_SOCKET, c::SO_PASSCRED, from_bool(passcred))
+}
+
+#[cfg(linux_kernel)]
+#[inline]
+pub(crate) fn get_socket_passcred(fd: BorrowedFd<'_>) -> io::Result<bool> {
+    getsockopt(fd, c::SOL_SOCKET, c::SO_PASSCRED).map(to_bool)
+}
+
+#[inline]
+pub(crate) fn set_socket_timeout(
+    fd: BorrowedFd<'_>,
+    id: Timeout,
+    timeout: Option<Duration>,
+) -> io::Result<()> {
+    let optname = match id {
+        Timeout::Recv => c::SO_RCVTIMEO,
+        Timeout::Send => c::SO_SNDTIMEO,
+    };
+
+    #[cfg(not(windows))]
+    let timeout = match timeout {
+        Some(timeout) => {
+            if timeout == Duration::ZERO {
+                return Err(io::Errno::INVAL);
+            }
+
+            // Rust's musl libc bindings deprecated `time_t` while they
+            // transition to 64-bit `time_t`. What we want here is just
+            // “whatever type `timeval`'s `tv_sec` is”, so we're ok using
+            // the deprecated type.
+            #[allow(deprecated)]
+            let tv_sec = timeout.as_secs().try_into().unwrap_or(c::time_t::MAX);
+
+            // `subsec_micros` rounds down, so we use `subsec_nanos` and
+            // manually round up.
+            let mut timeout = c::timeval {
+                tv_sec,
+                tv_usec: ((timeout.subsec_nanos() + 999) / 1000) as _,
+            };
+            if timeout.tv_sec == 0 && timeout.tv_usec == 0 {
+                timeout.tv_usec = 1;
+            }
+            timeout
+        }
+        None => c::timeval {
+            tv_sec: 0,
+            tv_usec: 0,
+        },
+    };
+
+    #[cfg(windows)]
+    let timeout: u32 = match timeout {
+        Some(timeout) => {
+            if timeout == Duration::ZERO {
+                return Err(io::Errno::INVAL);
+            }
+
+            // `as_millis` rounds down, so we use `as_nanos` and
+            // manually round up.
+            let mut timeout: u32 = ((timeout.as_nanos() + 999_999) / 1_000_000)
+                .try_into()
+                .map_err(|_convert_err| io::Errno::INVAL)?;
+            if timeout == 0 {
+                timeout = 1;
+            }
+            timeout
+        }
+        None => 0,
+    };
+
+    setsockopt(fd, c::SOL_SOCKET, optname, timeout)
+}
+
+#[inline]
+pub(crate) fn get_socket_timeout(fd: BorrowedFd<'_>, id: Timeout) -> io::Result<Option<Duration>> {
+    let optname = match id {
+        Timeout::Recv => c::SO_RCVTIMEO,
+        Timeout::Send => c::SO_SNDTIMEO,
+    };
+
+    #[cfg(not(windows))]
+    {
+        let timeout: c::timeval = getsockopt(fd, c::SOL_SOCKET, optname)?;
+        if timeout.tv_sec == 0 && timeout.tv_usec == 0 {
+            Ok(None)
+        } else {
+            Ok(Some(
+                Duration::from_secs(timeout.tv_sec as u64)
+                    + Duration::from_micros(timeout.tv_usec as u64),
+            ))
+        }
+    }
+
+    #[cfg(windows)]
+    {
+        let timeout: u32 = getsockopt(fd, c::SOL_SOCKET, optname)?;
+        if timeout == 0 {
+            Ok(None)
+        } else {
+            Ok(Some(Duration::from_millis(timeout as u64)))
+        }
+    }
+}
+
+#[cfg(any(apple, freebsdlike, target_os = "netbsd"))]
+#[inline]
+pub(crate) fn get_socket_nosigpipe(fd: BorrowedFd<'_>) -> io::Result<bool> {
+    getsockopt(fd, c::SOL_SOCKET, c::SO_NOSIGPIPE).map(to_bool)
+}
+
+#[cfg(any(apple, freebsdlike, target_os = "netbsd"))]
+#[inline]
+pub(crate) fn set_socket_nosigpipe(fd: BorrowedFd<'_>, val: bool) -> io::Result<()> {
+    setsockopt(fd, c::SOL_SOCKET, c::SO_NOSIGPIPE, from_bool(val))
+}
+
+#[inline]
+pub(crate) fn get_socket_error(fd: BorrowedFd<'_>) -> io::Result<Result<(), io::Errno>> {
+    let err: c::c_int = getsockopt(fd, c::SOL_SOCKET, c::SO_ERROR)?;
+    Ok(if err == 0 {
+        Ok(())
+    } else {
+        Err(io::Errno::from_raw_os_error(err))
+    })
+}
+
+#[inline]
+pub(crate) fn set_socket_keepalive(fd: BorrowedFd<'_>, keepalive: bool) -> io::Result<()> {
+    setsockopt(fd, c::SOL_SOCKET, c::SO_KEEPALIVE, from_bool(keepalive))
+}
+
+#[inline]
+pub(crate) fn get_socket_keepalive(fd: BorrowedFd<'_>) -> io::Result<bool> {
+    getsockopt(fd, c::SOL_SOCKET, c::SO_KEEPALIVE).map(to_bool)
+}
+
+#[inline]
+pub(crate) fn set_socket_recv_buffer_size(fd: BorrowedFd<'_>, size: usize) -> io::Result<()> {
+    let size: c::c_int = size.try_into().map_err(|_| io::Errno::INVAL)?;
+    setsockopt(fd, c::SOL_SOCKET, c::SO_RCVBUF, size)
+}
+
+#[inline]
+pub(crate) fn get_socket_recv_buffer_size(fd: BorrowedFd<'_>) -> io::Result<usize> {
+    getsockopt(fd, c::SOL_SOCKET, c::SO_RCVBUF).map(|size: u32| size as usize)
+}
+
+#[inline]
+pub(crate) fn set_socket_send_buffer_size(fd: BorrowedFd<'_>, size: usize) -> io::Result<()> {
+    let size: c::c_int = size.try_into().map_err(|_| io::Errno::INVAL)?;
+    setsockopt(fd, c::SOL_SOCKET, c::SO_SNDBUF, size)
+}
+
+#[inline]
+pub(crate) fn get_socket_send_buffer_size(fd: BorrowedFd<'_>) -> io::Result<usize> {
+    getsockopt(fd, c::SOL_SOCKET, c::SO_SNDBUF).map(|size: u32| size as usize)
+}
+
+#[inline]
+#[cfg(not(any(
+    apple,
+    windows,
+    target_os = "aix",
+    target_os = "dragonfly",
+    target_os = "emscripten",
+    target_os = "espidf",
+    target_os = "haiku",
+    target_os = "netbsd",
+    target_os = "nto",
+    target_os = "vita",
+)))]
+pub(crate) fn get_socket_domain(fd: BorrowedFd<'_>) -> io::Result<AddressFamily> {
+    let domain: c::c_int = getsockopt(fd, c::SOL_SOCKET, c::SO_DOMAIN)?;
+    Ok(AddressFamily(
+        domain.try_into().map_err(|_| io::Errno::OPNOTSUPP)?,
+    ))
+}
+
+#[inline]
+#[cfg(not(apple))] // Apple platforms declare the constant, but do not actually implement it.
+pub(crate) fn get_socket_acceptconn(fd: BorrowedFd<'_>) -> io::Result<bool> {
+    getsockopt(fd, c::SOL_SOCKET, c::SO_ACCEPTCONN).map(to_bool)
+}
+
+#[inline]
+pub(crate) fn set_socket_oobinline(fd: BorrowedFd<'_>, value: bool) -> io::Result<()> {
+    setsockopt(fd, c::SOL_SOCKET, c::SO_OOBINLINE, from_bool(value))
+}
+
+#[inline]
+pub(crate) fn get_socket_oobinline(fd: BorrowedFd<'_>) -> io::Result<bool> {
+    getsockopt(fd, c::SOL_SOCKET, c::SO_OOBINLINE).map(to_bool)
+}
+
+#[cfg(not(any(solarish, windows)))]
+#[inline]
+pub(crate) fn set_socket_reuseport(fd: BorrowedFd<'_>, value: bool) -> io::Result<()> {
+    setsockopt(fd, c::SOL_SOCKET, c::SO_REUSEPORT, from_bool(value))
+}
+
+#[cfg(not(any(solarish, windows)))]
+#[inline]
+pub(crate) fn get_socket_reuseport(fd: BorrowedFd<'_>) -> io::Result<bool> {
+    getsockopt(fd, c::SOL_SOCKET, c::SO_REUSEPORT).map(to_bool)
+}
+
+#[cfg(target_os = "freebsd")]
+#[inline]
+pub(crate) fn set_socket_reuseport_lb(fd: BorrowedFd<'_>, value: bool) -> io::Result<()> {
+    setsockopt(fd, c::SOL_SOCKET, c::SO_REUSEPORT_LB, from_bool(value))
+}
+
+#[cfg(target_os = "freebsd")]
+#[inline]
+pub(crate) fn get_socket_reuseport_lb(fd: BorrowedFd<'_>) -> io::Result<bool> {
+    getsockopt(fd, c::SOL_SOCKET, c::SO_REUSEPORT_LB).map(to_bool)
+}
+
+#[cfg(any(
+    linux_kernel,
+    target_os = "freebsd",
+    target_os = "fuchsia",
+    target_os = "openbsd",
+    target_os = "redox",
+    target_env = "newlib"
+))]
+#[inline]
+pub(crate) fn get_socket_protocol(fd: BorrowedFd<'_>) -> io::Result<Option<Protocol>> {
+    getsockopt(fd, c::SOL_SOCKET, c::SO_PROTOCOL)
+        .map(|raw| RawProtocol::new(raw).map(Protocol::from_raw))
+}
+
+#[cfg(target_os = "linux")]
+#[inline]
+pub(crate) fn get_socket_cookie(fd: BorrowedFd<'_>) -> io::Result<u64> {
+    getsockopt(fd, c::SOL_SOCKET, c::SO_COOKIE)
+}
+
+#[cfg(target_os = "linux")]
+#[inline]
+pub(crate) fn get_socket_incoming_cpu(fd: BorrowedFd<'_>) -> io::Result<u32> {
+    getsockopt(fd, c::SOL_SOCKET, c::SO_INCOMING_CPU)
+}
+
+#[cfg(target_os = "linux")]
+#[inline]
+pub(crate) fn set_socket_incoming_cpu(fd: BorrowedFd<'_>, value: u32) -> io::Result<()> {
+    setsockopt(fd, c::SOL_SOCKET, c::SO_INCOMING_CPU, value)
+}
+
+#[inline]
+pub(crate) fn set_ip_ttl(fd: BorrowedFd<'_>, ttl: u32) -> io::Result<()> {
+    setsockopt(fd, c::IPPROTO_IP, c::IP_TTL, ttl)
+}
+
+#[inline]
+pub(crate) fn get_ip_ttl(fd: BorrowedFd<'_>) -> io::Result<u32> {
+    getsockopt(fd, c::IPPROTO_IP, c::IP_TTL)
+}
+
+#[inline]
+pub(crate) fn set_ipv6_v6only(fd: BorrowedFd<'_>, only_v6: bool) -> io::Result<()> {
+    setsockopt(fd, c::IPPROTO_IPV6, c::IPV6_V6ONLY, from_bool(only_v6))
+}
+
+#[inline]
+pub(crate) fn get_ipv6_v6only(fd: BorrowedFd<'_>) -> io::Result<bool> {
+    getsockopt(fd, c::IPPROTO_IPV6, c::IPV6_V6ONLY).map(to_bool)
+}
+
+#[inline]
+pub(crate) fn set_ip_multicast_loop(fd: BorrowedFd<'_>, multicast_loop: bool) -> io::Result<()> {
+    setsockopt(
+        fd,
+        c::IPPROTO_IP,
+        c::IP_MULTICAST_LOOP,
+        from_bool(multicast_loop),
+    )
+}
+
+#[inline]
+pub(crate) fn get_ip_multicast_loop(fd: BorrowedFd<'_>) -> io::Result<bool> {
+    getsockopt(fd, c::IPPROTO_IP, c::IP_MULTICAST_LOOP).map(to_bool)
+}
+
+#[inline]
+pub(crate) fn set_ip_multicast_ttl(fd: BorrowedFd<'_>, multicast_ttl: u32) -> io::Result<()> {
+    setsockopt(fd, c::IPPROTO_IP, c::IP_MULTICAST_TTL, multicast_ttl)
+}
+
+#[inline]
+pub(crate) fn get_ip_multicast_ttl(fd: BorrowedFd<'_>) -> io::Result<u32> {
+    getsockopt(fd, c::IPPROTO_IP, c::IP_MULTICAST_TTL)
+}
+
+#[inline]
+pub(crate) fn set_ipv6_multicast_loop(fd: BorrowedFd<'_>, multicast_loop: bool) -> io::Result<()> {
+    setsockopt(
+        fd,
+        c::IPPROTO_IPV6,
+        c::IPV6_MULTICAST_LOOP,
+        from_bool(multicast_loop),
+    )
+}
+
+#[inline]
+pub(crate) fn get_ipv6_multicast_loop(fd: BorrowedFd<'_>) -> io::Result<bool> {
+    getsockopt(fd, c::IPPROTO_IPV6, c::IPV6_MULTICAST_LOOP).map(to_bool)
+}
+
+#[inline]
+pub(crate) fn set_ipv6_multicast_hops(fd: BorrowedFd<'_>, multicast_hops: u32) -> io::Result<()> {
+    setsockopt(fd, c::IPPROTO_IP, c::IPV6_MULTICAST_HOPS, multicast_hops)
+}
+
+#[inline]
+pub(crate) fn get_ipv6_multicast_hops(fd: BorrowedFd<'_>) -> io::Result<u32> {
+    getsockopt(fd, c::IPPROTO_IP, c::IPV6_MULTICAST_HOPS)
+}
+
+#[inline]
+pub(crate) fn set_ip_add_membership(
+    fd: BorrowedFd<'_>,
+    multiaddr: &Ipv4Addr,
+    interface: &Ipv4Addr,
+) -> io::Result<()> {
+    let mreq = to_ip_mreq(multiaddr, interface);
+    setsockopt(fd, c::IPPROTO_IP, c::IP_ADD_MEMBERSHIP, mreq)
+}
+
+#[cfg(any(
+    apple,
+    freebsdlike,
+    linux_like,
+    target_os = "fuchsia",
+    target_os = "openbsd"
+))]
+#[inline]
+pub(crate) fn set_ip_add_membership_with_ifindex(
+    fd: BorrowedFd<'_>,
+    multiaddr: &Ipv4Addr,
+    address: &Ipv4Addr,
+    ifindex: i32,
+) -> io::Result<()> {
+    let mreqn = to_ip_mreqn(multiaddr, address, ifindex);
+    setsockopt(fd, c::IPPROTO_IP, c::IP_ADD_MEMBERSHIP, mreqn)
+}
+
+#[cfg(any(apple, freebsdlike, linux_like, solarish, target_os = "aix"))]
+#[inline]
+pub(crate) fn set_ip_add_source_membership(
+    fd: BorrowedFd<'_>,
+    multiaddr: &Ipv4Addr,
+    interface: &Ipv4Addr,
+    sourceaddr: &Ipv4Addr,
+) -> io::Result<()> {
+    let mreq_source = to_imr_source(multiaddr, interface, sourceaddr);
+    setsockopt(fd, c::IPPROTO_IP, c::IP_ADD_SOURCE_MEMBERSHIP, mreq_source)
+}
+
+#[cfg(any(apple, freebsdlike, linux_like, solarish, target_os = "aix"))]
+#[inline]
+pub(crate) fn set_ip_drop_source_membership(
+    fd: BorrowedFd<'_>,
+    multiaddr: &Ipv4Addr,
+    interface: &Ipv4Addr,
+    sourceaddr: &Ipv4Addr,
+) -> io::Result<()> {
+    let mreq_source = to_imr_source(multiaddr, interface, sourceaddr);
+    setsockopt(fd, c::IPPROTO_IP, c::IP_DROP_SOURCE_MEMBERSHIP, mreq_source)
+}
+
+#[inline]
+pub(crate) fn set_ipv6_add_membership(
+    fd: BorrowedFd<'_>,
+    multiaddr: &Ipv6Addr,
+    interface: u32,
+) -> io::Result<()> {
+    #[cfg(not(any(
+        bsd,
+        solarish,
+        target_os = "haiku",
+        target_os = "l4re",
+        target_os = "nto"
+    )))]
+    use c::IPV6_ADD_MEMBERSHIP;
+    #[cfg(any(
+        bsd,
+        solarish,
+        target_os = "haiku",
+        target_os = "l4re",
+        target_os = "nto"
+    ))]
+    use c::IPV6_JOIN_GROUP as IPV6_ADD_MEMBERSHIP;
+
+    let mreq = to_ipv6mr(multiaddr, interface);
+    setsockopt(fd, c::IPPROTO_IPV6, IPV6_ADD_MEMBERSHIP, mreq)
+}
+
+#[inline]
+pub(crate) fn set_ip_drop_membership(
+    fd: BorrowedFd<'_>,
+    multiaddr: &Ipv4Addr,
+    interface: &Ipv4Addr,
+) -> io::Result<()> {
+    let mreq = to_ip_mreq(multiaddr, interface);
+    setsockopt(fd, c::IPPROTO_IP, c::IP_DROP_MEMBERSHIP, mreq)
+}
+
+#[cfg(any(
+    apple,
+    freebsdlike,
+    linux_like,
+    target_os = "fuchsia",
+    target_os = "openbsd"
+))]
+#[inline]
+pub(crate) fn set_ip_drop_membership_with_ifindex(
+    fd: BorrowedFd<'_>,
+    multiaddr: &Ipv4Addr,
+    address: &Ipv4Addr,
+    ifindex: i32,
+) -> io::Result<()> {
+    let mreqn = to_ip_mreqn(multiaddr, address, ifindex);
+    setsockopt(fd, c::IPPROTO_IP, c::IP_DROP_MEMBERSHIP, mreqn)
+}
+
+#[inline]
+pub(crate) fn set_ipv6_drop_membership(
+    fd: BorrowedFd<'_>,
+    multiaddr: &Ipv6Addr,
+    interface: u32,
+) -> io::Result<()> {
+    #[cfg(not(any(
+        bsd,
+        solarish,
+        target_os = "haiku",
+        target_os = "l4re",
+        target_os = "nto"
+    )))]
+    use c::IPV6_DROP_MEMBERSHIP;
+    #[cfg(any(
+        bsd,
+        solarish,
+        target_os = "haiku",
+        target_os = "l4re",
+        target_os = "nto"
+    ))]
+    use c::IPV6_LEAVE_GROUP as IPV6_DROP_MEMBERSHIP;
+
+    let mreq = to_ipv6mr(multiaddr, interface);
+    setsockopt(fd, c::IPPROTO_IPV6, IPV6_DROP_MEMBERSHIP, mreq)
+}
+
+#[inline]
+pub(crate) fn get_ipv6_unicast_hops(fd: BorrowedFd<'_>) -> io::Result<u8> {
+    getsockopt(fd, c::IPPROTO_IPV6, c::IPV6_UNICAST_HOPS).map(|hops: c::c_int| hops as u8)
+}
+
+#[inline]
+pub(crate) fn set_ipv6_unicast_hops(fd: BorrowedFd<'_>, hops: Option<u8>) -> io::Result<()> {
+    let hops = match hops {
+        Some(hops) => hops as c::c_int,
+        None => -1,
+    };
+    setsockopt(fd, c::IPPROTO_IPV6, c::IPV6_UNICAST_HOPS, hops)
+}
+
+#[cfg(any(
+    bsd,
+    linux_like,
+    target_os = "aix",
+    target_os = "fuchsia",
+    target_os = "haiku",
+    target_os = "nto",
+    target_env = "newlib"
+))]
+#[inline]
+pub(crate) fn set_ip_tos(fd: BorrowedFd<'_>, value: u8) -> io::Result<()> {
+    setsockopt(fd, c::IPPROTO_IP, c::IP_TOS, i32::from(value))
+}
+
+#[cfg(any(
+    bsd,
+    linux_like,
+    target_os = "aix",
+    target_os = "fuchsia",
+    target_os = "haiku",
+    target_os = "nto",
+    target_env = "newlib"
+))]
+#[inline]
+pub(crate) fn get_ip_tos(fd: BorrowedFd<'_>) -> io::Result<u8> {
+    let value: i32 = getsockopt(fd, c::IPPROTO_IP, c::IP_TOS)?;
+    Ok(value as u8)
+}
+
+#[cfg(any(apple, linux_like, target_os = "freebsd", target_os = "fuchsia"))]
+#[inline]
+pub(crate) fn set_ip_recvtos(fd: BorrowedFd<'_>, value: bool) -> io::Result<()> {
+    setsockopt(fd, c::IPPROTO_IP, c::IP_RECVTOS, from_bool(value))
+}
+
+#[cfg(any(apple, linux_like, target_os = "freebsd", target_os = "fuchsia"))]
+#[inline]
+pub(crate) fn get_ip_recvtos(fd: BorrowedFd<'_>) -> io::Result<bool> {
+    getsockopt(fd, c::IPPROTO_IP, c::IP_RECVTOS).map(to_bool)
+}
+
+#[cfg(any(
+    bsd,
+    linux_like,
+    target_os = "aix",
+    target_os = "fuchsia",
+    target_os = "nto"
+))]
+#[inline]
+pub(crate) fn set_ipv6_recvtclass(fd: BorrowedFd<'_>, value: bool) -> io::Result<()> {
+    setsockopt(fd, c::IPPROTO_IPV6, c::IPV6_RECVTCLASS, from_bool(value))
+}
+
+#[cfg(any(
+    bsd,
+    linux_like,
+    target_os = "aix",
+    target_os = "fuchsia",
+    target_os = "nto"
+))]
+#[inline]
+pub(crate) fn get_ipv6_recvtclass(fd: BorrowedFd<'_>) -> io::Result<bool> {
+    getsockopt(fd, c::IPPROTO_IPV6, c::IPV6_RECVTCLASS).map(to_bool)
+}
+
+#[cfg(any(linux_kernel, target_os = "fuchsia"))]
+#[inline]
+pub(crate) fn set_ip_freebind(fd: BorrowedFd<'_>, value: bool) -> io::Result<()> {
+    setsockopt(fd, c::IPPROTO_IP, c::IP_FREEBIND, from_bool(value))
+}
+
+#[cfg(any(linux_kernel, target_os = "fuchsia"))]
+#[inline]
+pub(crate) fn get_ip_freebind(fd: BorrowedFd<'_>) -> io::Result<bool> {
+    getsockopt(fd, c::IPPROTO_IP, c::IP_FREEBIND).map(to_bool)
+}
+
+#[cfg(linux_kernel)]
+#[inline]
+pub(crate) fn set_ipv6_freebind(fd: BorrowedFd<'_>, value: bool) -> io::Result<()> {
+    setsockopt(fd, c::IPPROTO_IPV6, c::IPV6_FREEBIND, from_bool(value))
+}
+
+#[cfg(linux_kernel)]
+#[inline]
+pub(crate) fn get_ipv6_freebind(fd: BorrowedFd<'_>) -> io::Result<bool> {
+    getsockopt(fd, c::IPPROTO_IPV6, c::IPV6_FREEBIND).map(to_bool)
+}
+
+#[cfg(any(linux_kernel, target_os = "fuchsia"))]
+#[inline]
+pub(crate) fn get_ip_original_dst(fd: BorrowedFd<'_>) -> io::Result<SocketAddrV4> {
+    let level = c::IPPROTO_IP;
+    let optname = c::SO_ORIGINAL_DST;
+    let mut value = MaybeUninit::<SocketAddrStorage>::uninit();
+    let mut optlen = core::mem::size_of_val(&value).try_into().unwrap();
+
+    getsockopt_raw(fd, level, optname, &mut value, &mut optlen)?;
+
+    let any = unsafe { SocketAddrAny::read(value.as_ptr(), optlen as usize)? };
+    match any {
+        SocketAddrAny::V4(v4) => Ok(v4),
+        _ => unreachable!(),
+    }
+}
+
+#[cfg(linux_kernel)]
+#[inline]
+pub(crate) fn get_ipv6_original_dst(fd: BorrowedFd<'_>) -> io::Result<SocketAddrV6> {
+    let level = c::IPPROTO_IPV6;
+    let optname = c::IP6T_SO_ORIGINAL_DST;
+    let mut value = MaybeUninit::<SocketAddrStorage>::uninit();
+    let mut optlen = core::mem::size_of_val(&value).try_into().unwrap();
+
+    getsockopt_raw(fd, level, optname, &mut value, &mut optlen)?;
+
+    let any = unsafe { SocketAddrAny::read(value.as_ptr(), optlen as usize)? };
+    match any {
+        SocketAddrAny::V6(v6) => Ok(v6),
+        _ => unreachable!(),
+    }
+}
+
+#[cfg(not(any(
+    solarish,
+    windows,
+    target_os = "espidf",
+    target_os = "haiku",
+    target_os = "vita"
+)))]
+#[inline]
+pub(crate) fn set_ipv6_tclass(fd: BorrowedFd<'_>, value: u32) -> io::Result<()> {
+    setsockopt(fd, c::IPPROTO_IPV6, c::IPV6_TCLASS, value)
+}
+
+#[cfg(not(any(
+    solarish,
+    windows,
+    target_os = "espidf",
+    target_os = "haiku",
+    target_os = "vita"
+)))]
+#[inline]
+pub(crate) fn get_ipv6_tclass(fd: BorrowedFd<'_>) -> io::Result<u32> {
+    getsockopt(fd, c::IPPROTO_IPV6, c::IPV6_TCLASS)
+}
+
+#[inline]
+pub(crate) fn set_tcp_nodelay(fd: BorrowedFd<'_>, nodelay: bool) -> io::Result<()> {
+    setsockopt(fd, c::IPPROTO_TCP, c::TCP_NODELAY, from_bool(nodelay))
+}
+
+#[inline]
+pub(crate) fn get_tcp_nodelay(fd: BorrowedFd<'_>) -> io::Result<bool> {
+    getsockopt(fd, c::IPPROTO_TCP, c::TCP_NODELAY).map(to_bool)
+}
+
+#[inline]
+#[cfg(not(any(target_os = "openbsd", target_os = "haiku", target_os = "nto")))]
+pub(crate) fn set_tcp_keepcnt(fd: BorrowedFd<'_>, count: u32) -> io::Result<()> {
+    setsockopt(fd, c::IPPROTO_TCP, c::TCP_KEEPCNT, count)
+}
+
+#[inline]
+#[cfg(not(any(target_os = "openbsd", target_os = "haiku", target_os = "nto")))]
+pub(crate) fn get_tcp_keepcnt(fd: BorrowedFd<'_>) -> io::Result<u32> {
+    getsockopt(fd, c::IPPROTO_TCP, c::TCP_KEEPCNT)
+}
+
+#[inline]
+#[cfg(not(any(target_os = "openbsd", target_os = "haiku", target_os = "nto")))]
+pub(crate) fn set_tcp_keepidle(fd: BorrowedFd<'_>, duration: Duration) -> io::Result<()> {
+    let secs: c::c_uint = duration_to_secs(duration)?;
+    setsockopt(fd, c::IPPROTO_TCP, TCP_KEEPIDLE, secs)
+}
+
+#[inline]
+#[cfg(not(any(target_os = "openbsd", target_os = "haiku", target_os = "nto")))]
+pub(crate) fn get_tcp_keepidle(fd: BorrowedFd<'_>) -> io::Result<Duration> {
+    let secs: c::c_uint = getsockopt(fd, c::IPPROTO_TCP, TCP_KEEPIDLE)?;
+    Ok(Duration::from_secs(secs as u64))
+}
+
+#[inline]
+#[cfg(not(any(target_os = "openbsd", target_os = "haiku", target_os = "nto")))]
+pub(crate) fn set_tcp_keepintvl(fd: BorrowedFd<'_>, duration: Duration) -> io::Result<()> {
+    let secs: c::c_uint = duration_to_secs(duration)?;
+    setsockopt(fd, c::IPPROTO_TCP, c::TCP_KEEPINTVL, secs)
+}
+
+#[inline]
+#[cfg(not(any(target_os = "openbsd", target_os = "haiku", target_os = "nto")))]
+pub(crate) fn get_tcp_keepintvl(fd: BorrowedFd<'_>) -> io::Result<Duration> {
+    let secs: c::c_uint = getsockopt(fd, c::IPPROTO_TCP, c::TCP_KEEPINTVL)?;
+    Ok(Duration::from_secs(secs as u64))
+}
+
+#[inline]
+#[cfg(any(linux_like, target_os = "fuchsia"))]
+pub(crate) fn set_tcp_user_timeout(fd: BorrowedFd<'_>, value: u32) -> io::Result<()> {
+    setsockopt(fd, c::IPPROTO_TCP, c::TCP_USER_TIMEOUT, value)
+}
+
+#[inline]
+#[cfg(any(linux_like, target_os = "fuchsia"))]
+pub(crate) fn get_tcp_user_timeout(fd: BorrowedFd<'_>) -> io::Result<u32> {
+    getsockopt(fd, c::IPPROTO_TCP, c::TCP_USER_TIMEOUT)
+}
+
+#[cfg(any(linux_like, target_os = "fuchsia"))]
+#[inline]
+pub(crate) fn set_tcp_quickack(fd: BorrowedFd<'_>, value: bool) -> io::Result<()> {
+    setsockopt(fd, c::IPPROTO_TCP, c::TCP_QUICKACK, from_bool(value))
+}
+
+#[cfg(any(linux_like, target_os = "fuchsia"))]
+#[inline]
+pub(crate) fn get_tcp_quickack(fd: BorrowedFd<'_>) -> io::Result<bool> {
+    getsockopt(fd, c::IPPROTO_TCP, c::TCP_QUICKACK).map(to_bool)
+}
+
+#[cfg(any(
+    linux_like,
+    target_os = "freebsd",
+    target_os = "fuchsia",
+    target_os = "illumos"
+))]
+#[inline]
+pub(crate) fn set_tcp_congestion(fd: BorrowedFd<'_>, value: &str) -> io::Result<()> {
+    let level = c::IPPROTO_TCP;
+    let optname = c::TCP_CONGESTION;
+    let optlen = value.len().try_into().unwrap();
+    setsockopt_raw(fd, level, optname, value.as_ptr(), optlen)
+}
+
+#[cfg(feature = "alloc")]
+#[cfg(any(
+    linux_like,
+    target_os = "freebsd",
+    target_os = "fuchsia",
+    target_os = "illumos"
+))]
+#[inline]
+pub(crate) fn get_tcp_congestion(fd: BorrowedFd<'_>) -> io::Result<String> {
+    let level = c::IPPROTO_TCP;
+    let optname = c::TCP_CONGESTION;
+    const OPTLEN: c::socklen_t = 16;
+    let mut value = MaybeUninit::<[MaybeUninit<u8>; OPTLEN as usize]>::uninit();
+    let mut optlen = OPTLEN;
+    getsockopt_raw(fd, level, optname, &mut value, &mut optlen)?;
+    unsafe {
+        let value = value.assume_init();
+        let slice: &[u8] = core::mem::transmute(&value[..optlen as usize]);
+        assert!(slice.iter().any(|b| *b == b'\0'));
+        Ok(
+            core::str::from_utf8(CStr::from_ptr(slice.as_ptr().cast()).to_bytes())
+                .unwrap()
+                .to_owned(),
+        )
+    }
+}
+
+#[cfg(any(linux_like, target_os = "fuchsia"))]
+#[inline]
+pub(crate) fn set_tcp_thin_linear_timeouts(fd: BorrowedFd<'_>, value: bool) -> io::Result<()> {
+    setsockopt(
+        fd,
+        c::IPPROTO_TCP,
+        c::TCP_THIN_LINEAR_TIMEOUTS,
+        from_bool(value),
+    )
+}
+
+#[cfg(any(linux_like, target_os = "fuchsia"))]
+#[inline]
+pub(crate) fn get_tcp_thin_linear_timeouts(fd: BorrowedFd<'_>) -> io::Result<bool> {
+    getsockopt(fd, c::IPPROTO_TCP, c::TCP_THIN_LINEAR_TIMEOUTS).map(to_bool)
+}
+
+#[cfg(any(linux_like, solarish, target_os = "fuchsia"))]
+#[inline]
+pub(crate) fn set_tcp_cork(fd: BorrowedFd<'_>, value: bool) -> io::Result<()> {
+    setsockopt(fd, c::IPPROTO_TCP, c::TCP_CORK, from_bool(value))
+}
+
+#[cfg(any(linux_like, solarish, target_os = "fuchsia"))]
+#[inline]
+pub(crate) fn get_tcp_cork(fd: BorrowedFd<'_>) -> io::Result<bool> {
+    getsockopt(fd, c::IPPROTO_TCP, c::TCP_CORK).map(to_bool)
+}
+
+#[cfg(linux_kernel)]
+#[inline]
+pub(crate) fn get_socket_peercred(fd: BorrowedFd<'_>) -> io::Result<UCred> {
+    getsockopt(fd, c::SOL_SOCKET, c::SO_PEERCRED)
+}
+
+#[inline]
+fn to_ip_mreq(multiaddr: &Ipv4Addr, interface: &Ipv4Addr) -> c::ip_mreq {
+    c::ip_mreq {
+        imr_multiaddr: to_imr_addr(multiaddr),
+        imr_interface: to_imr_addr(interface),
+    }
+}
+
+#[cfg(any(
+    apple,
+    freebsdlike,
+    linux_like,
+    target_os = "fuchsia",
+    target_os = "openbsd"
+))]
+#[inline]
+fn to_ip_mreqn(multiaddr: &Ipv4Addr, address: &Ipv4Addr, ifindex: i32) -> c::ip_mreqn {
+    c::ip_mreqn {
+        imr_multiaddr: to_imr_addr(multiaddr),
+        imr_address: to_imr_addr(address),
+        imr_ifindex: ifindex,
+    }
+}
+
+#[cfg(any(apple, freebsdlike, linux_like, solarish, target_os = "aix"))]
+#[inline]
+fn to_imr_source(
+    multiaddr: &Ipv4Addr,
+    interface: &Ipv4Addr,
+    sourceaddr: &Ipv4Addr,
+) -> c::ip_mreq_source {
+    c::ip_mreq_source {
+        imr_multiaddr: to_imr_addr(multiaddr),
+        imr_interface: to_imr_addr(interface),
+        imr_sourceaddr: to_imr_addr(sourceaddr),
+    }
+}
+
+#[inline]
+fn to_imr_addr(addr: &Ipv4Addr) -> c::in_addr {
+    in_addr_new(u32::from_ne_bytes(addr.octets()))
+}
+
+#[inline]
+fn to_ipv6mr(multiaddr: &Ipv6Addr, interface: u32) -> c::ipv6_mreq {
+    c::ipv6_mreq {
+        ipv6mr_multiaddr: to_ipv6mr_multiaddr(multiaddr),
+        ipv6mr_interface: to_ipv6mr_interface(interface),
+    }
+}
+
+#[inline]
+fn to_ipv6mr_multiaddr(multiaddr: &Ipv6Addr) -> c::in6_addr {
+    in6_addr_new(multiaddr.octets())
+}
+
+#[cfg(target_os = "android")]
+#[inline]
+fn to_ipv6mr_interface(interface: u32) -> c::c_int {
+    interface as c::c_int
+}
+
+#[cfg(not(target_os = "android"))]
+#[inline]
+fn to_ipv6mr_interface(interface: u32) -> c::c_uint {
+    interface as c::c_uint
+}
+
+// `getsockopt` and `setsockopt` represent boolean values as integers.
+#[cfg(not(windows))]
+type RawSocketBool = c::c_int;
+#[cfg(windows)]
+type RawSocketBool = BOOL;
+
+// Wrap `RawSocketBool` in a newtype to discourage misuse.
+#[repr(transparent)]
+#[derive(Copy, Clone)]
+struct SocketBool(RawSocketBool);
+
+// Convert from a `bool` to a `SocketBool`.
+#[inline]
+fn from_bool(value: bool) -> SocketBool {
+    SocketBool(value.into())
+}
+
+// Convert from a `SocketBool` to a `bool`.
+#[inline]
+fn to_bool(value: SocketBool) -> bool {
+    value.0 != 0
+}
+
+/// Convert to seconds, rounding up if necessary.
+#[inline]
+fn duration_to_secs<T: TryFrom<u64>>(duration: Duration) -> io::Result<T> {
+    let mut secs = duration.as_secs();
+    if duration.subsec_nanos() != 0 {
+        secs = secs.checked_add(1).ok_or(io::Errno::INVAL)?;
+    }
+    T::try_from(secs).map_err(|_e| io::Errno::INVAL)
+}