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|
use crate::cmp;
use crate::ffi::CStr;
use crate::io::{self, BorrowedBuf, BorrowedCursor, IoSlice, IoSliceMut};
use crate::mem;
use crate::net::{Shutdown, SocketAddr};
use crate::os::unix::io::{AsFd, AsRawFd, BorrowedFd, FromRawFd, IntoRawFd, RawFd};
use crate::str;
use crate::sys::fd::FileDesc;
use crate::sys_common::net::{getsockopt, setsockopt, sockaddr_to_addr};
use crate::sys_common::{AsInner, FromInner, IntoInner};
use crate::time::{Duration, Instant};
use libc::{c_int, c_void, size_t, sockaddr, socklen_t, MSG_PEEK};
cfg_if::cfg_if! {
if #[cfg(target_vendor = "apple")] {
use libc::SO_LINGER_SEC as SO_LINGER;
} else {
use libc::SO_LINGER;
}
}
pub use crate::sys::{cvt, cvt_r};
#[allow(unused_extern_crates)]
pub extern crate libc as netc;
pub type wrlen_t = size_t;
pub struct Socket(FileDesc);
pub fn init() {}
pub fn cvt_gai(err: c_int) -> io::Result<()> {
if err == 0 {
return Ok(());
}
// We may need to trigger a glibc workaround. See on_resolver_failure() for details.
on_resolver_failure();
#[cfg(not(target_os = "espidf"))]
if err == libc::EAI_SYSTEM {
return Err(io::Error::last_os_error());
}
#[cfg(not(target_os = "espidf"))]
let detail = unsafe {
str::from_utf8(CStr::from_ptr(libc::gai_strerror(err)).to_bytes()).unwrap().to_owned()
};
#[cfg(target_os = "espidf")]
let detail = "";
Err(io::Error::new(
io::ErrorKind::Uncategorized,
&format!("failed to lookup address information: {detail}")[..],
))
}
impl Socket {
pub fn new(addr: &SocketAddr, ty: c_int) -> io::Result<Socket> {
let fam = match *addr {
SocketAddr::V4(..) => libc::AF_INET,
SocketAddr::V6(..) => libc::AF_INET6,
};
Socket::new_raw(fam, ty)
}
pub fn new_raw(fam: c_int, ty: c_int) -> io::Result<Socket> {
unsafe {
cfg_if::cfg_if! {
if #[cfg(any(
target_os = "android",
target_os = "dragonfly",
target_os = "freebsd",
target_os = "illumos",
target_os = "hurd",
target_os = "linux",
target_os = "netbsd",
target_os = "openbsd",
target_os = "nto",
))] {
// On platforms that support it we pass the SOCK_CLOEXEC
// flag to atomically create the socket and set it as
// CLOEXEC. On Linux this was added in 2.6.27.
let fd = cvt(libc::socket(fam, ty | libc::SOCK_CLOEXEC, 0))?;
Ok(Socket(FileDesc::from_raw_fd(fd)))
} else {
let fd = cvt(libc::socket(fam, ty, 0))?;
let fd = FileDesc::from_raw_fd(fd);
fd.set_cloexec()?;
let socket = Socket(fd);
// macOS and iOS use `SO_NOSIGPIPE` as a `setsockopt`
// flag to disable `SIGPIPE` emission on socket.
#[cfg(target_vendor = "apple")]
setsockopt(&socket, libc::SOL_SOCKET, libc::SO_NOSIGPIPE, 1)?;
Ok(socket)
}
}
}
}
#[cfg(not(any(target_os = "vxworks", target_os = "vita")))]
pub fn new_pair(fam: c_int, ty: c_int) -> io::Result<(Socket, Socket)> {
unsafe {
let mut fds = [0, 0];
cfg_if::cfg_if! {
if #[cfg(any(
target_os = "android",
target_os = "dragonfly",
target_os = "freebsd",
target_os = "illumos",
target_os = "linux",
target_os = "hurd",
target_os = "netbsd",
target_os = "openbsd",
target_os = "nto",
))] {
// Like above, set cloexec atomically
cvt(libc::socketpair(fam, ty | libc::SOCK_CLOEXEC, 0, fds.as_mut_ptr()))?;
Ok((Socket(FileDesc::from_raw_fd(fds[0])), Socket(FileDesc::from_raw_fd(fds[1]))))
} else {
cvt(libc::socketpair(fam, ty, 0, fds.as_mut_ptr()))?;
let a = FileDesc::from_raw_fd(fds[0]);
let b = FileDesc::from_raw_fd(fds[1]);
a.set_cloexec()?;
b.set_cloexec()?;
Ok((Socket(a), Socket(b)))
}
}
}
}
#[cfg(any(target_os = "vxworks", target_os = "vita"))]
pub fn new_pair(_fam: c_int, _ty: c_int) -> io::Result<(Socket, Socket)> {
unimplemented!()
}
pub fn connect_timeout(&self, addr: &SocketAddr, timeout: Duration) -> io::Result<()> {
self.set_nonblocking(true)?;
let r = unsafe {
let (addr, len) = addr.into_inner();
cvt(libc::connect(self.as_raw_fd(), addr.as_ptr(), len))
};
self.set_nonblocking(false)?;
match r {
Ok(_) => return Ok(()),
// there's no ErrorKind for EINPROGRESS :(
Err(ref e) if e.raw_os_error() == Some(libc::EINPROGRESS) => {}
Err(e) => return Err(e),
}
let mut pollfd = libc::pollfd { fd: self.as_raw_fd(), events: libc::POLLOUT, revents: 0 };
if timeout.as_secs() == 0 && timeout.subsec_nanos() == 0 {
return Err(io::const_io_error!(
io::ErrorKind::InvalidInput,
"cannot set a 0 duration timeout",
));
}
let start = Instant::now();
loop {
let elapsed = start.elapsed();
if elapsed >= timeout {
return Err(io::const_io_error!(io::ErrorKind::TimedOut, "connection timed out"));
}
let timeout = timeout - elapsed;
let mut timeout = timeout
.as_secs()
.saturating_mul(1_000)
.saturating_add(timeout.subsec_nanos() as u64 / 1_000_000);
if timeout == 0 {
timeout = 1;
}
let timeout = cmp::min(timeout, c_int::MAX as u64) as c_int;
match unsafe { libc::poll(&mut pollfd, 1, timeout) } {
-1 => {
let err = io::Error::last_os_error();
if !err.is_interrupted() {
return Err(err);
}
}
0 => {}
_ => {
// linux returns POLLOUT|POLLERR|POLLHUP for refused connections (!), so look
// for POLLHUP rather than read readiness
if pollfd.revents & libc::POLLHUP != 0 {
let e = self.take_error()?.unwrap_or_else(|| {
io::const_io_error!(
io::ErrorKind::Uncategorized,
"no error set after POLLHUP",
)
});
return Err(e);
}
return Ok(());
}
}
}
}
pub fn accept(&self, storage: *mut sockaddr, len: *mut socklen_t) -> io::Result<Socket> {
// Unfortunately the only known way right now to accept a socket and
// atomically set the CLOEXEC flag is to use the `accept4` syscall on
// platforms that support it. On Linux, this was added in 2.6.28,
// glibc 2.10 and musl 0.9.5.
cfg_if::cfg_if! {
if #[cfg(any(
target_os = "android",
target_os = "dragonfly",
target_os = "freebsd",
target_os = "illumos",
target_os = "linux",
target_os = "hurd",
target_os = "netbsd",
target_os = "openbsd",
))] {
unsafe {
let fd = cvt_r(|| libc::accept4(self.as_raw_fd(), storage, len, libc::SOCK_CLOEXEC))?;
Ok(Socket(FileDesc::from_raw_fd(fd)))
}
} else {
unsafe {
let fd = cvt_r(|| libc::accept(self.as_raw_fd(), storage, len))?;
let fd = FileDesc::from_raw_fd(fd);
fd.set_cloexec()?;
Ok(Socket(fd))
}
}
}
}
pub fn duplicate(&self) -> io::Result<Socket> {
self.0.duplicate().map(Socket)
}
fn recv_with_flags(&self, mut buf: BorrowedCursor<'_>, flags: c_int) -> io::Result<()> {
let ret = cvt(unsafe {
libc::recv(
self.as_raw_fd(),
buf.as_mut().as_mut_ptr() as *mut c_void,
buf.capacity(),
flags,
)
})?;
unsafe {
buf.advance(ret as usize);
}
Ok(())
}
pub fn read(&self, buf: &mut [u8]) -> io::Result<usize> {
let mut buf = BorrowedBuf::from(buf);
self.recv_with_flags(buf.unfilled(), 0)?;
Ok(buf.len())
}
pub fn peek(&self, buf: &mut [u8]) -> io::Result<usize> {
let mut buf = BorrowedBuf::from(buf);
self.recv_with_flags(buf.unfilled(), MSG_PEEK)?;
Ok(buf.len())
}
pub fn read_buf(&self, buf: BorrowedCursor<'_>) -> io::Result<()> {
self.recv_with_flags(buf, 0)
}
pub fn read_vectored(&self, bufs: &mut [IoSliceMut<'_>]) -> io::Result<usize> {
self.0.read_vectored(bufs)
}
#[inline]
pub fn is_read_vectored(&self) -> bool {
self.0.is_read_vectored()
}
fn recv_from_with_flags(
&self,
buf: &mut [u8],
flags: c_int,
) -> io::Result<(usize, SocketAddr)> {
let mut storage: libc::sockaddr_storage = unsafe { mem::zeroed() };
let mut addrlen = mem::size_of_val(&storage) as libc::socklen_t;
let n = cvt(unsafe {
libc::recvfrom(
self.as_raw_fd(),
buf.as_mut_ptr() as *mut c_void,
buf.len(),
flags,
&mut storage as *mut _ as *mut _,
&mut addrlen,
)
})?;
Ok((n as usize, sockaddr_to_addr(&storage, addrlen as usize)?))
}
pub fn recv_from(&self, buf: &mut [u8]) -> io::Result<(usize, SocketAddr)> {
self.recv_from_with_flags(buf, 0)
}
#[cfg(any(target_os = "android", target_os = "linux"))]
pub fn recv_msg(&self, msg: &mut libc::msghdr) -> io::Result<usize> {
let n = cvt(unsafe { libc::recvmsg(self.as_raw_fd(), msg, libc::MSG_CMSG_CLOEXEC) })?;
Ok(n as usize)
}
pub fn peek_from(&self, buf: &mut [u8]) -> io::Result<(usize, SocketAddr)> {
self.recv_from_with_flags(buf, MSG_PEEK)
}
pub fn write(&self, buf: &[u8]) -> io::Result<usize> {
self.0.write(buf)
}
pub fn write_vectored(&self, bufs: &[IoSlice<'_>]) -> io::Result<usize> {
self.0.write_vectored(bufs)
}
#[inline]
pub fn is_write_vectored(&self) -> bool {
self.0.is_write_vectored()
}
#[cfg(any(target_os = "android", target_os = "linux"))]
pub fn send_msg(&self, msg: &mut libc::msghdr) -> io::Result<usize> {
let n = cvt(unsafe { libc::sendmsg(self.as_raw_fd(), msg, 0) })?;
Ok(n as usize)
}
pub fn set_timeout(&self, dur: Option<Duration>, kind: libc::c_int) -> io::Result<()> {
let timeout = match dur {
Some(dur) => {
if dur.as_secs() == 0 && dur.subsec_nanos() == 0 {
return Err(io::const_io_error!(
io::ErrorKind::InvalidInput,
"cannot set a 0 duration timeout",
));
}
let secs = if dur.as_secs() > libc::time_t::MAX as u64 {
libc::time_t::MAX
} else {
dur.as_secs() as libc::time_t
};
let mut timeout = libc::timeval {
tv_sec: secs,
tv_usec: dur.subsec_micros() as libc::suseconds_t,
};
if timeout.tv_sec == 0 && timeout.tv_usec == 0 {
timeout.tv_usec = 1;
}
timeout
}
None => libc::timeval { tv_sec: 0, tv_usec: 0 },
};
setsockopt(self, libc::SOL_SOCKET, kind, timeout)
}
pub fn timeout(&self, kind: libc::c_int) -> io::Result<Option<Duration>> {
let raw: libc::timeval = getsockopt(self, libc::SOL_SOCKET, kind)?;
if raw.tv_sec == 0 && raw.tv_usec == 0 {
Ok(None)
} else {
let sec = raw.tv_sec as u64;
let nsec = (raw.tv_usec as u32) * 1000;
Ok(Some(Duration::new(sec, nsec)))
}
}
pub fn shutdown(&self, how: Shutdown) -> io::Result<()> {
let how = match how {
Shutdown::Write => libc::SHUT_WR,
Shutdown::Read => libc::SHUT_RD,
Shutdown::Both => libc::SHUT_RDWR,
};
cvt(unsafe { libc::shutdown(self.as_raw_fd(), how) })?;
Ok(())
}
pub fn set_linger(&self, linger: Option<Duration>) -> io::Result<()> {
let linger = libc::linger {
l_onoff: linger.is_some() as libc::c_int,
l_linger: linger.unwrap_or_default().as_secs() as libc::c_int,
};
setsockopt(self, libc::SOL_SOCKET, SO_LINGER, linger)
}
pub fn linger(&self) -> io::Result<Option<Duration>> {
let val: libc::linger = getsockopt(self, libc::SOL_SOCKET, SO_LINGER)?;
Ok((val.l_onoff != 0).then(|| Duration::from_secs(val.l_linger as u64)))
}
pub fn set_nodelay(&self, nodelay: bool) -> io::Result<()> {
setsockopt(self, libc::IPPROTO_TCP, libc::TCP_NODELAY, nodelay as c_int)
}
pub fn nodelay(&self) -> io::Result<bool> {
let raw: c_int = getsockopt(self, libc::IPPROTO_TCP, libc::TCP_NODELAY)?;
Ok(raw != 0)
}
#[cfg(any(target_os = "android", target_os = "linux",))]
pub fn set_quickack(&self, quickack: bool) -> io::Result<()> {
setsockopt(self, libc::IPPROTO_TCP, libc::TCP_QUICKACK, quickack as c_int)
}
#[cfg(any(target_os = "android", target_os = "linux",))]
pub fn quickack(&self) -> io::Result<bool> {
let raw: c_int = getsockopt(self, libc::IPPROTO_TCP, libc::TCP_QUICKACK)?;
Ok(raw != 0)
}
#[cfg(any(target_os = "android", target_os = "linux",))]
pub fn set_passcred(&self, passcred: bool) -> io::Result<()> {
setsockopt(self, libc::SOL_SOCKET, libc::SO_PASSCRED, passcred as libc::c_int)
}
#[cfg(any(target_os = "android", target_os = "linux",))]
pub fn passcred(&self) -> io::Result<bool> {
let passcred: libc::c_int = getsockopt(self, libc::SOL_SOCKET, libc::SO_PASSCRED)?;
Ok(passcred != 0)
}
#[cfg(target_os = "netbsd")]
pub fn set_passcred(&self, passcred: bool) -> io::Result<()> {
setsockopt(self, 0 as libc::c_int, libc::LOCAL_CREDS, passcred as libc::c_int)
}
#[cfg(target_os = "netbsd")]
pub fn passcred(&self) -> io::Result<bool> {
let passcred: libc::c_int = getsockopt(self, 0 as libc::c_int, libc::LOCAL_CREDS)?;
Ok(passcred != 0)
}
#[cfg(target_os = "freebsd")]
pub fn set_passcred(&self, passcred: bool) -> io::Result<()> {
setsockopt(self, libc::AF_LOCAL, libc::LOCAL_CREDS_PERSISTENT, passcred as libc::c_int)
}
#[cfg(target_os = "freebsd")]
pub fn passcred(&self) -> io::Result<bool> {
let passcred: libc::c_int = getsockopt(self, libc::AF_LOCAL, libc::LOCAL_CREDS_PERSISTENT)?;
Ok(passcred != 0)
}
#[cfg(not(any(target_os = "solaris", target_os = "illumos", target_os = "vita")))]
pub fn set_nonblocking(&self, nonblocking: bool) -> io::Result<()> {
let mut nonblocking = nonblocking as libc::c_int;
cvt(unsafe { libc::ioctl(self.as_raw_fd(), libc::FIONBIO, &mut nonblocking) }).map(drop)
}
#[cfg(target_os = "vita")]
pub fn set_nonblocking(&self, nonblocking: bool) -> io::Result<()> {
let option = nonblocking as libc::c_int;
setsockopt(self, libc::SOL_SOCKET, libc::SO_NONBLOCK, option)
}
#[cfg(any(target_os = "solaris", target_os = "illumos"))]
pub fn set_nonblocking(&self, nonblocking: bool) -> io::Result<()> {
// FIONBIO is inadequate for sockets on illumos/Solaris, so use the
// fcntl(F_[GS]ETFL)-based method provided by FileDesc instead.
self.0.set_nonblocking(nonblocking)
}
#[cfg(any(target_os = "linux", target_os = "freebsd", target_os = "openbsd"))]
pub fn set_mark(&self, mark: u32) -> io::Result<()> {
#[cfg(target_os = "linux")]
let option = libc::SO_MARK;
#[cfg(target_os = "freebsd")]
let option = libc::SO_USER_COOKIE;
#[cfg(target_os = "openbsd")]
let option = libc::SO_RTABLE;
setsockopt(self, libc::SOL_SOCKET, option, mark as libc::c_int)
}
pub fn take_error(&self) -> io::Result<Option<io::Error>> {
let raw: c_int = getsockopt(self, libc::SOL_SOCKET, libc::SO_ERROR)?;
if raw == 0 { Ok(None) } else { Ok(Some(io::Error::from_raw_os_error(raw as i32))) }
}
// This is used by sys_common code to abstract over Windows and Unix.
pub fn as_raw(&self) -> RawFd {
self.as_raw_fd()
}
}
impl AsInner<FileDesc> for Socket {
#[inline]
fn as_inner(&self) -> &FileDesc {
&self.0
}
}
impl IntoInner<FileDesc> for Socket {
fn into_inner(self) -> FileDesc {
self.0
}
}
impl FromInner<FileDesc> for Socket {
fn from_inner(file_desc: FileDesc) -> Self {
Self(file_desc)
}
}
impl AsFd for Socket {
fn as_fd(&self) -> BorrowedFd<'_> {
self.0.as_fd()
}
}
impl AsRawFd for Socket {
#[inline]
fn as_raw_fd(&self) -> RawFd {
self.0.as_raw_fd()
}
}
impl IntoRawFd for Socket {
fn into_raw_fd(self) -> RawFd {
self.0.into_raw_fd()
}
}
impl FromRawFd for Socket {
unsafe fn from_raw_fd(raw_fd: RawFd) -> Self {
Self(FromRawFd::from_raw_fd(raw_fd))
}
}
// In versions of glibc prior to 2.26, there's a bug where the DNS resolver
// will cache the contents of /etc/resolv.conf, so changes to that file on disk
// can be ignored by a long-running program. That can break DNS lookups on e.g.
// laptops where the network comes and goes. See
// https://sourceware.org/bugzilla/show_bug.cgi?id=984. Note however that some
// distros including Debian have patched glibc to fix this for a long time.
//
// A workaround for this bug is to call the res_init libc function, to clear
// the cached configs. Unfortunately, while we believe glibc's implementation
// of res_init is thread-safe, we know that other implementations are not
// (https://github.com/rust-lang/rust/issues/43592). Code here in std could
// try to synchronize its res_init calls with a Mutex, but that wouldn't
// protect programs that call into libc in other ways. So instead of calling
// res_init unconditionally, we call it only when we detect we're linking
// against glibc version < 2.26. (That is, when we both know its needed and
// believe it's thread-safe).
#[cfg(all(target_os = "linux", target_env = "gnu"))]
fn on_resolver_failure() {
use crate::sys;
// If the version fails to parse, we treat it the same as "not glibc".
if let Some(version) = sys::os::glibc_version() {
if version < (2, 26) {
unsafe { libc::res_init() };
}
}
}
#[cfg(not(all(target_os = "linux", target_env = "gnu")))]
fn on_resolver_failure() {}
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