mio/sys/unix/
net.rs

1use std::io;
2use std::mem::size_of;
3use std::net::{Ipv4Addr, Ipv6Addr, SocketAddr, SocketAddrV4, SocketAddrV6};
4
5pub(crate) fn new_ip_socket(addr: SocketAddr, socket_type: libc::c_int) -> io::Result<libc::c_int> {
6    let domain = match addr {
7        SocketAddr::V4(..) => libc::AF_INET,
8        SocketAddr::V6(..) => libc::AF_INET6,
9    };
10
11    new_socket(domain, socket_type)
12}
13
14/// Create a new non-blocking socket.
15pub(crate) fn new_socket(domain: libc::c_int, socket_type: libc::c_int) -> io::Result<libc::c_int> {
16    #[cfg(any(
17        target_os = "android",
18        target_os = "dragonfly",
19        target_os = "freebsd",
20        target_os = "hurd",
21        target_os = "illumos",
22        target_os = "linux",
23        target_os = "netbsd",
24        target_os = "openbsd",
25        target_os = "solaris",
26        target_os = "hermit",
27        target_os = "cygwin",
28    ))]
29    let socket_type = socket_type | libc::SOCK_NONBLOCK | libc::SOCK_CLOEXEC;
30    // WASI doesn't have the concept of `fork`ing or `exec`ing processes, so
31    // `SOCK_CLOEXEC` neither exists nor is relevant:
32    #[cfg(target_os = "wasi")]
33    let socket_type = socket_type | libc::SOCK_NONBLOCK;
34    #[cfg(target_os = "nto")]
35    let socket_type = socket_type | libc::SOCK_CLOEXEC;
36
37    let socket = syscall!(socket(domain, socket_type, 0))?;
38
39    // Mimic `libstd` and set `SO_NOSIGPIPE` on apple systems.
40    #[cfg(any(
41        target_os = "ios",
42        target_os = "macos",
43        target_os = "tvos",
44        target_os = "visionos",
45        target_os = "watchos",
46    ))]
47    if let Err(err) = syscall!(setsockopt(
48        socket,
49        libc::SOL_SOCKET,
50        libc::SO_NOSIGPIPE,
51        &1 as *const libc::c_int as *const libc::c_void,
52        size_of::<libc::c_int>() as libc::socklen_t
53    )) {
54        let _ = syscall!(close(socket));
55        return Err(err);
56    }
57
58    // Darwin (and others) doesn't have SOCK_NONBLOCK or SOCK_CLOEXEC.
59    #[cfg(any(
60        target_os = "aix",
61        target_os = "ios",
62        target_os = "macos",
63        target_os = "tvos",
64        target_os = "visionos",
65        target_os = "watchos",
66        target_os = "espidf",
67        target_os = "vita",
68        target_os = "nto",
69    ))]
70    {
71        if let Err(err) = syscall!(fcntl(socket, libc::F_SETFL, libc::O_NONBLOCK)) {
72            let _ = syscall!(close(socket));
73            return Err(err);
74        }
75        #[cfg(not(any(target_os = "espidf", target_os = "vita", target_os = "nto")))]
76        if let Err(err) = syscall!(fcntl(socket, libc::F_SETFD, libc::FD_CLOEXEC)) {
77            let _ = syscall!(close(socket));
78            return Err(err);
79        }
80    }
81
82    Ok(socket)
83}
84
85/// A type with the same memory layout as `libc::sockaddr`. Used in converting Rust level
86/// SocketAddr* types into their system representation. The benefit of this specific
87/// type over using `libc::sockaddr_storage` is that this type is exactly as large as it
88/// needs to be and not a lot larger. And it can be initialized cleaner from Rust.
89#[repr(C)]
90pub(crate) union SocketAddrCRepr {
91    v4: libc::sockaddr_in,
92    v6: libc::sockaddr_in6,
93}
94
95impl SocketAddrCRepr {
96    pub(crate) fn as_ptr(&self) -> *const libc::sockaddr {
97        self as *const _ as *const libc::sockaddr
98    }
99}
100
101/// Converts a Rust `SocketAddr` into the system representation.
102pub(crate) fn socket_addr(addr: &SocketAddr) -> (SocketAddrCRepr, libc::socklen_t) {
103    match addr {
104        SocketAddr::V4(ref addr) => {
105            // `s_addr` is stored as BE on all machine and the array is in BE order.
106            // So the native endian conversion method is used so that it's never swapped.
107            let sin_addr = libc::in_addr {
108                s_addr: u32::from_ne_bytes(addr.ip().octets()),
109            };
110
111            let sockaddr_in = libc::sockaddr_in {
112                sin_family: libc::AF_INET as libc::sa_family_t,
113                sin_port: addr.port().to_be(),
114                sin_addr,
115                #[cfg(not(any(target_os = "haiku", target_os = "vita", target_os = "wasi")))]
116                sin_zero: [0; 8],
117                #[cfg(target_os = "haiku")]
118                sin_zero: [0; 24],
119                #[cfg(target_os = "vita")]
120                sin_zero: [0; 6],
121                #[cfg(any(
122                    target_os = "aix",
123                    target_os = "dragonfly",
124                    target_os = "freebsd",
125                    target_os = "haiku",
126                    target_os = "hurd",
127                    target_os = "ios",
128                    target_os = "macos",
129                    target_os = "netbsd",
130                    target_os = "openbsd",
131                    target_os = "tvos",
132                    target_os = "visionos",
133                    target_os = "watchos",
134                    target_os = "espidf",
135                    target_os = "vita",
136                    target_os = "hermit",
137                    target_os = "nto",
138                ))]
139                sin_len: 0,
140                #[cfg(target_os = "vita")]
141                sin_vport: addr.port().to_be(),
142            };
143
144            let sockaddr = SocketAddrCRepr { v4: sockaddr_in };
145            let socklen = size_of::<libc::sockaddr_in>() as libc::socklen_t;
146            (sockaddr, socklen)
147        }
148        SocketAddr::V6(ref addr) => {
149            let sockaddr_in6 = libc::sockaddr_in6 {
150                sin6_family: libc::AF_INET6 as libc::sa_family_t,
151                sin6_port: addr.port().to_be(),
152                sin6_addr: libc::in6_addr {
153                    s6_addr: addr.ip().octets(),
154                },
155                sin6_flowinfo: addr.flowinfo(),
156                sin6_scope_id: addr.scope_id(),
157                #[cfg(any(
158                    target_os = "aix",
159                    target_os = "dragonfly",
160                    target_os = "freebsd",
161                    target_os = "haiku",
162                    target_os = "hurd",
163                    target_os = "ios",
164                    target_os = "macos",
165                    target_os = "netbsd",
166                    target_os = "openbsd",
167                    target_os = "tvos",
168                    target_os = "visionos",
169                    target_os = "watchos",
170                    target_os = "espidf",
171                    target_os = "vita",
172                    target_os = "nto",
173                    target_os = "hermit",
174                ))]
175                sin6_len: 0,
176                #[cfg(target_os = "vita")]
177                sin6_vport: addr.port().to_be(),
178                #[cfg(any(target_os = "illumos", target_os = "solaris"))]
179                __sin6_src_id: 0,
180            };
181
182            let sockaddr = SocketAddrCRepr { v6: sockaddr_in6 };
183            let socklen = size_of::<libc::sockaddr_in6>() as libc::socklen_t;
184            (sockaddr, socklen)
185        }
186    }
187}
188
189/// Converts a `libc::sockaddr` compatible struct into a native Rust `SocketAddr`.
190///
191/// # Safety
192///
193/// `storage` must have the `ss_family` field correctly initialized.
194/// `storage` must be initialised to a `sockaddr_in` or `sockaddr_in6`.
195pub(crate) unsafe fn to_socket_addr(
196    storage: *const libc::sockaddr_storage,
197) -> io::Result<SocketAddr> {
198    match (*storage).ss_family as libc::c_int {
199        libc::AF_INET => {
200            // Safety: if the ss_family field is AF_INET then storage must be a sockaddr_in.
201            let addr: &libc::sockaddr_in = &*(storage as *const libc::sockaddr_in);
202            let ip = Ipv4Addr::from(addr.sin_addr.s_addr.to_ne_bytes());
203            let port = u16::from_be(addr.sin_port);
204            Ok(SocketAddr::V4(SocketAddrV4::new(ip, port)))
205        }
206        libc::AF_INET6 => {
207            // Safety: if the ss_family field is AF_INET6 then storage must be a sockaddr_in6.
208            let addr: &libc::sockaddr_in6 = &*(storage as *const libc::sockaddr_in6);
209            let ip = Ipv6Addr::from(addr.sin6_addr.s6_addr);
210            let port = u16::from_be(addr.sin6_port);
211            Ok(SocketAddr::V6(SocketAddrV6::new(
212                ip,
213                port,
214                addr.sin6_flowinfo,
215                addr.sin6_scope_id,
216            )))
217        }
218        _ => Err(io::ErrorKind::InvalidInput.into()),
219    }
220}
mio/sys/unix/net.rs

mio/sys/unix/
net.rs
