1 files changed, 195 insertions, 0 deletions
diff --git a/vendor/rustix/src/backend/linux_raw/net/read_sockaddr.rs b/vendor/rustix/src/backend/linux_raw/net/read_sockaddr.rs
new file mode 100644
index 0000000..5a91707
--- /dev/null
+++ b/vendor/rustix/src/backend/linux_raw/net/read_sockaddr.rs
@@ -0,0 +1,195 @@
+//! The BSD sockets API requires us to read the `ss_family` field before we can
+//! interpret the rest of a `sockaddr` produced by the kernel.
+#![allow(unsafe_code)]
+
+use crate::backend::c;
+use crate::io;
+use crate::net::{Ipv4Addr, Ipv6Addr, SocketAddrAny, SocketAddrUnix, SocketAddrV4, SocketAddrV6};
+use core::mem::size_of;
+use core::slice;
+
+// This must match the header of `sockaddr`.
+#[repr(C)]
+struct sockaddr_header {
+    ss_family: u16,
+}
+
+/// Read the `ss_family` field from a socket address returned from the OS.
+///
+/// # Safety
+///
+/// `storage` must point to a valid socket address returned from the OS.
+#[inline]
+unsafe fn read_ss_family(storage: *const c::sockaddr) -> u16 {
+    // Assert that we know the layout of `sockaddr`.
+    let _ = c::sockaddr {
+        __storage: c::sockaddr_storage {
+            __bindgen_anon_1: linux_raw_sys::net::__kernel_sockaddr_storage__bindgen_ty_1 {
+                __bindgen_anon_1:
+                    linux_raw_sys::net::__kernel_sockaddr_storage__bindgen_ty_1__bindgen_ty_1 {
+                        ss_family: 0_u16,
+                        __data: [0; 126_usize],
+                    },
+            },
+        },
+    };
+
+    (*storage.cast::<sockaddr_header>()).ss_family
+}
+
+/// Set the `ss_family` field of a socket address to `AF_UNSPEC`, so that we
+/// can test for `AF_UNSPEC` to test whether it was stored to.
+#[inline]
+pub(crate) unsafe fn initialize_family_to_unspec(storage: *mut c::sockaddr) {
+    (*storage.cast::<sockaddr_header>()).ss_family = c::AF_UNSPEC as _;
+}
+
+/// Read a socket address encoded in a platform-specific format.
+///
+/// # Safety
+///
+/// `storage` must point to valid socket address storage.
+pub(crate) unsafe fn read_sockaddr(
+    storage: *const c::sockaddr,
+    len: usize,
+) -> io::Result<SocketAddrAny> {
+    let offsetof_sun_path = super::addr::offsetof_sun_path();
+
+    if len < size_of::<c::sa_family_t>() {
+        return Err(io::Errno::INVAL);
+    }
+    match read_ss_family(storage).into() {
+        c::AF_INET => {
+            if len < size_of::<c::sockaddr_in>() {
+                return Err(io::Errno::INVAL);
+            }
+            let decode = &*storage.cast::<c::sockaddr_in>();
+            Ok(SocketAddrAny::V4(SocketAddrV4::new(
+                Ipv4Addr::from(u32::from_be(decode.sin_addr.s_addr)),
+                u16::from_be(decode.sin_port),
+            )))
+        }
+        c::AF_INET6 => {
+            if len < size_of::<c::sockaddr_in6>() {
+                return Err(io::Errno::INVAL);
+            }
+            let decode = &*storage.cast::<c::sockaddr_in6>();
+            Ok(SocketAddrAny::V6(SocketAddrV6::new(
+                Ipv6Addr::from(decode.sin6_addr.in6_u.u6_addr8),
+                u16::from_be(decode.sin6_port),
+                u32::from_be(decode.sin6_flowinfo),
+                decode.sin6_scope_id,
+            )))
+        }
+        c::AF_UNIX => {
+            if len < offsetof_sun_path {
+                return Err(io::Errno::INVAL);
+            }
+            if len == offsetof_sun_path {
+                Ok(SocketAddrAny::Unix(SocketAddrUnix::new(&[][..])?))
+            } else {
+                let decode = &*storage.cast::<c::sockaddr_un>();
+
+                // On Linux check for Linux's [abstract namespace].
+                //
+                // [abstract namespace]: https://man7.org/linux/man-pages/man7/unix.7.html
+                if decode.sun_path[0] == 0 {
+                    let bytes = &decode.sun_path[1..len - offsetof_sun_path];
+
+                    // SAFETY: Convert `&[c_char]` to `&[u8]`.
+                    let bytes = slice::from_raw_parts(bytes.as_ptr().cast::<u8>(), bytes.len());
+
+                    return SocketAddrUnix::new_abstract_name(bytes).map(SocketAddrAny::Unix);
+                }
+
+                // Otherwise we expect a NUL-terminated filesystem path.
+                let bytes = &decode.sun_path[..len - 1 - offsetof_sun_path];
+
+                // SAFETY: Convert `&[c_char]` to `&[u8]`.
+                let bytes = slice::from_raw_parts(bytes.as_ptr().cast::<u8>(), bytes.len());
+
+                assert_eq!(decode.sun_path[len - 1 - offsetof_sun_path], 0);
+                Ok(SocketAddrAny::Unix(SocketAddrUnix::new(bytes)?))
+            }
+        }
+        _ => Err(io::Errno::NOTSUP),
+    }
+}
+
+/// Read an optional socket address returned from the OS.
+///
+/// # Safety
+///
+/// `storage` must point to a valid socket address returned from the OS.
+pub(crate) unsafe fn maybe_read_sockaddr_os(
+    storage: *const c::sockaddr,
+    len: usize,
+) -> Option<SocketAddrAny> {
+    if len == 0 {
+        None
+    } else {
+        Some(read_sockaddr_os(storage, len))
+    }
+}
+
+/// Read a socket address returned from the OS.
+///
+/// # Safety
+///
+/// `storage` must point to a valid socket address returned from the OS.
+pub(crate) unsafe fn read_sockaddr_os(storage: *const c::sockaddr, len: usize) -> SocketAddrAny {
+    let offsetof_sun_path = super::addr::offsetof_sun_path();
+
+    assert!(len >= size_of::<c::sa_family_t>());
+    match read_ss_family(storage).into() {
+        c::AF_INET => {
+            assert!(len >= size_of::<c::sockaddr_in>());
+            let decode = &*storage.cast::<c::sockaddr_in>();
+            SocketAddrAny::V4(SocketAddrV4::new(
+                Ipv4Addr::from(u32::from_be(decode.sin_addr.s_addr)),
+                u16::from_be(decode.sin_port),
+            ))
+        }
+        c::AF_INET6 => {
+            assert!(len >= size_of::<c::sockaddr_in6>());
+            let decode = &*storage.cast::<c::sockaddr_in6>();
+            SocketAddrAny::V6(SocketAddrV6::new(
+                Ipv6Addr::from(decode.sin6_addr.in6_u.u6_addr8),
+                u16::from_be(decode.sin6_port),
+                u32::from_be(decode.sin6_flowinfo),
+                decode.sin6_scope_id,
+            ))
+        }
+        c::AF_UNIX => {
+            assert!(len >= offsetof_sun_path);
+            if len == offsetof_sun_path {
+                SocketAddrAny::Unix(SocketAddrUnix::new(&[][..]).unwrap())
+            } else {
+                let decode = &*storage.cast::<c::sockaddr_un>();
+
+                // On Linux check for Linux's [abstract namespace].
+                //
+                // [abstract namespace]: https://man7.org/linux/man-pages/man7/unix.7.html
+                if decode.sun_path[0] == 0 {
+                    let bytes = &decode.sun_path[1..len - offsetof_sun_path];
+
+                    // SAFETY: Convert `&[c_char]` to `&[u8]`.
+                    let bytes = slice::from_raw_parts(bytes.as_ptr().cast::<u8>(), bytes.len());
+
+                    return SocketAddrAny::Unix(SocketAddrUnix::new_abstract_name(bytes).unwrap());
+                }
+
+                // Otherwise we expect a NUL-terminated filesystem path.
+                assert_eq!(decode.sun_path[len - 1 - offsetof_sun_path], 0);
+
+                let bytes = &decode.sun_path[..len - 1 - offsetof_sun_path];
+
+                // SAFETY: Convert `&[c_char]` to `&[u8]`.
+                let bytes = slice::from_raw_parts(bytes.as_ptr().cast::<u8>(), bytes.len());
+
+                SocketAddrAny::Unix(SocketAddrUnix::new(bytes).unwrap())
+            }
+        }
+        other => unimplemented!("{:?}", other),
+    }
+}