Add setter and getter for multicast_ifv4 and multicast_ifv6 (#1291)

al8n · web-flow · commit 06ad93d7d82d · 2025-01-30T09:07:26.000-08:00
* Add setter and getter for `multicast_ifv4` and `multicast_ifv6`

* Add `set_ip_multicast_if_with_ifindex` and fix naming

* make all ifindex to `u32`
diff --git a/src/backend/libc/net/sockopt.rs b/src/backend/libc/net/sockopt.rs
@@ -480,6 +480,44 @@ pub(crate) fn 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_if(fd: BorrowedFd<'_>, value: &Ipv4Addr) -> io::Result<()> {
+    setsockopt(fd, c::IPPROTO_IP, c::IP_MULTICAST_IF, to_imr_addr(value))
+}
+
+#[inline]
+pub(crate) fn ip_multicast_if(fd: BorrowedFd<'_>) -> io::Result<Ipv4Addr> {
+    getsockopt(fd, c::IPPROTO_IP, c::IP_MULTICAST_IF).map(from_in_addr)
+}
+
+#[cfg(any(
+    apple,
+    freebsdlike,
+    linux_like,
+    target_os = "fuchsia",
+    target_os = "openbsd"
+))]
+#[inline]
+pub(crate) fn set_ip_multicast_if_with_ifindex(
+    fd: BorrowedFd<'_>,
+    multiaddr: &Ipv4Addr,
+    address: &Ipv4Addr,
+    ifindex: u32,
+) -> io::Result<()> {
+    let mreqn = to_ip_mreqn(multiaddr, address, ifindex as i32);
+    setsockopt(fd, c::IPPROTO_IP, c::IP_MULTICAST_IF, mreqn)
+}
+
+#[inline]
+pub(crate) fn set_ipv6_multicast_if(fd: BorrowedFd<'_>, value: u32) -> io::Result<()> {
+    setsockopt(fd, c::IPPROTO_IPV6, c::IPV6_MULTICAST_IF, value as c::c_int)
+}
+
+#[inline]
+pub(crate) fn ipv6_multicast_if(fd: BorrowedFd<'_>) -> io::Result<u32> {
+    getsockopt(fd, c::IPPROTO_IPV6, c::IPV6_MULTICAST_IF)
+}
+
 #[inline]
 pub(crate) fn set_ip_multicast_loop(fd: BorrowedFd<'_>, multicast_loop: bool) -> io::Result<()> {
     setsockopt(
@@ -552,9 +590,9 @@ pub(crate) fn set_ip_add_membership_with_ifindex(
     fd: BorrowedFd<'_>,
     multiaddr: &Ipv4Addr,
     address: &Ipv4Addr,
-    ifindex: i32,
+    ifindex: u32,
 ) -> io::Result<()> {
-    let mreqn = to_ip_mreqn(multiaddr, address, ifindex);
+    let mreqn = to_ip_mreqn(multiaddr, address, ifindex as i32);
     setsockopt(fd, c::IPPROTO_IP, c::IP_ADD_MEMBERSHIP, mreqn)
 }
 
@@ -631,9 +669,9 @@ pub(crate) fn set_ip_drop_membership_with_ifindex(
     fd: BorrowedFd<'_>,
     multiaddr: &Ipv4Addr,
     address: &Ipv4Addr,
-    ifindex: i32,
+    ifindex: u32,
 ) -> io::Result<()> {
-    let mreqn = to_ip_mreqn(multiaddr, address, ifindex);
+    let mreqn = to_ip_mreqn(multiaddr, address, ifindex as i32);
     setsockopt(fd, c::IPPROTO_IP, c::IP_DROP_MEMBERSHIP, mreqn)
 }
 
@@ -1150,6 +1188,17 @@ fn to_ip_mreq(multiaddr: &Ipv4Addr, interface: &Ipv4Addr) -> c::ip_mreq {
     }
 }
 
+#[cfg(not(windows))]
+#[inline]
+fn from_in_addr(in_addr: c::in_addr) -> Ipv4Addr {
+    Ipv4Addr::from(in_addr.s_addr.to_ne_bytes())
+}
+
+#[cfg(windows)]
+fn from_in_addr(in_addr: c::in_addr) -> Ipv4Addr {
+    Ipv4Addr::from(unsafe { in_addr.S_un.S_addr.to_ne_bytes() })
+}
+
 #[cfg(any(
     apple,
     freebsdlike,
diff --git a/src/backend/linux_raw/net/sockopt.rs b/src/backend/linux_raw/net/sockopt.rs
@@ -24,9 +24,12 @@ use alloc::borrow::ToOwned;
 use alloc::string::String;
 use core::mem::MaybeUninit;
 use core::time::Duration;
-use linux_raw_sys::general::{__kernel_old_timeval, __kernel_sock_timeval};
 #[cfg(target_os = "linux")]
 use linux_raw_sys::xdp::{xdp_mmap_offsets, xdp_statistics, xdp_statistics_v1};
+use linux_raw_sys::{
+    general::{__kernel_old_timeval, __kernel_sock_timeval},
+    net::{IPV6_MULTICAST_IF, IP_MULTICAST_IF},
+};
 #[cfg(target_arch = "x86")]
 use {
     crate::backend::conv::{slice_just_addr, x86_sys},
@@ -445,6 +448,37 @@ pub(crate) fn 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_if_with_ifindex(
+    fd: BorrowedFd<'_>,
+    multiaddr: &Ipv4Addr,
+    address: &Ipv4Addr,
+    ifindex: u32,
+) -> io::Result<()> {
+    let mreqn = to_ip_mreqn(multiaddr, address, ifindex as i32);
+    setsockopt(fd, c::IPPROTO_IP, IP_MULTICAST_IF, mreqn)
+}
+
+#[inline]
+pub(crate) fn set_ip_multicast_if(fd: BorrowedFd<'_>, value: &Ipv4Addr) -> io::Result<()> {
+    setsockopt(fd, c::IPPROTO_IP, IP_MULTICAST_IF, to_imr_addr(value))
+}
+
+#[inline]
+pub(crate) fn ip_multicast_if(fd: BorrowedFd<'_>) -> io::Result<Ipv4Addr> {
+    getsockopt(fd, c::IPPROTO_IP, IP_MULTICAST_IF).map(from_in_addr)
+}
+
+#[inline]
+pub(crate) fn set_ipv6_multicast_if(fd: BorrowedFd<'_>, value: u32) -> io::Result<()> {
+    setsockopt(fd, c::IPPROTO_IPV6, IPV6_MULTICAST_IF, value as c::c_int)
+}
+
+#[inline]
+pub(crate) fn ipv6_multicast_if(fd: BorrowedFd<'_>) -> io::Result<u32> {
+    getsockopt(fd, c::IPPROTO_IPV6, IPV6_MULTICAST_IF)
+}
+
 #[inline]
 pub(crate) fn set_ip_multicast_loop(fd: BorrowedFd<'_>, multicast_loop: bool) -> io::Result<()> {
     setsockopt(
@@ -510,9 +544,9 @@ pub(crate) fn set_ip_add_membership_with_ifindex(
     fd: BorrowedFd<'_>,
     multiaddr: &Ipv4Addr,
     address: &Ipv4Addr,
-    ifindex: i32,
+    ifindex: u32,
 ) -> io::Result<()> {
-    let mreqn = to_ip_mreqn(multiaddr, address, ifindex);
+    let mreqn = to_ip_mreqn(multiaddr, address, ifindex as i32);
     setsockopt(fd, c::IPPROTO_IP, c::IP_ADD_MEMBERSHIP, mreqn)
 }
 
@@ -563,9 +597,9 @@ pub(crate) fn set_ip_drop_membership_with_ifindex(
     fd: BorrowedFd<'_>,
     multiaddr: &Ipv4Addr,
     address: &Ipv4Addr,
-    ifindex: i32,
+    ifindex: u32,
 ) -> io::Result<()> {
-    let mreqn = to_ip_mreqn(multiaddr, address, ifindex);
+    let mreqn = to_ip_mreqn(multiaddr, address, ifindex as i32);
     setsockopt(fd, c::IPPROTO_IP, c::IP_DROP_MEMBERSHIP, mreqn)
 }
 
@@ -976,6 +1010,11 @@ pub(crate) fn xdp_options(fd: BorrowedFd<'_>) -> io::Result<XdpOptionsFlags> {
     getsockopt(fd, c::SOL_XDP, c::XDP_OPTIONS)
 }
 
+#[inline]
+fn from_in_addr(in_addr: c::in_addr) -> Ipv4Addr {
+    Ipv4Addr::from(in_addr.s_addr.to_ne_bytes())
+}
+
 #[inline]
 fn to_ip_mreq(multiaddr: &Ipv4Addr, interface: &Ipv4Addr) -> c::ip_mreq {
     c::ip_mreq {
diff --git a/src/net/sockopt.rs b/src/net/sockopt.rs
@@ -647,6 +647,77 @@ pub fn ipv6_v6only<Fd: AsFd>(fd: Fd) -> io::Result<bool> {
     backend::net::sockopt::ipv6_v6only(fd.as_fd())
 }
 
+/// `setsockopt(fd, IPPROTO_IP, IP_MULTICAST_IF, value)`
+///
+/// See the [module-level documentation] for more.
+///
+/// [module-level documentation]: self#references-for-get_ip_-and-set_ip_-functions
+#[inline]
+#[doc(alias = "IP_MULTICAST_IF")]
+pub fn set_ip_multicast_if<Fd: AsFd>(fd: Fd, value: &Ipv4Addr) -> io::Result<()> {
+    backend::net::sockopt::set_ip_multicast_if(fd.as_fd(), value)
+}
+
+/// `setsockopt(fd, IPPROTO_IP, IP_MULTICAST_IF, multiaddr, address,
+/// ifindex)`
+///
+/// This is similar to [`set_ip_multicast_if`] but additionally allows an
+/// `ifindex` value to be given.
+///
+/// See the [module-level documentation] for more.
+///
+/// [module-level documentation]: self#references-for-get_ip_-and-set_ip_-functions
+#[cfg(any(
+    apple,
+    freebsdlike,
+    linux_like,
+    target_os = "fuchsia",
+    target_os = "openbsd"
+))]
+#[inline]
+#[doc(alias = "IP_MULTICAST_IF")]
+pub fn set_ip_multicast_if_with_ifindex<Fd: AsFd>(
+    fd: Fd,
+    multiaddr: &Ipv4Addr,
+    address: &Ipv4Addr,
+    ifindex: u32,
+) -> io::Result<()> {
+    backend::net::sockopt::set_ip_multicast_if_with_ifindex(fd.as_fd(), multiaddr, address, ifindex)
+}
+
+/// `getsockopt(fd, IPPROTO_IP, IP_MULTICAST_IF)`
+///
+/// See the [module-level documentation] for more.
+///
+/// [module-level documentation]: self#references-for-get_ip_-and-set_ip_-functions
+#[inline]
+#[doc(alias = "IP_MULTICAST_IF")]
+pub fn ip_multicast_if<Fd: AsFd>(fd: Fd) -> io::Result<Ipv4Addr> {
+    backend::net::sockopt::ip_multicast_if(fd.as_fd())
+}
+
+/// `setsockopt(fd, IPPROTO_IPV6, IPV6_MULTICAST_IF, value)`
+///
+/// See the [module-level documentation] for more.
+///
+/// [module-level documentation]: self#references-for-get_ip_-and-set_ip_-functions
+#[inline]
+#[doc(alias = "IPV6_MULTICAST_IF")]
+pub fn set_ipv6_multicast_if<Fd: AsFd>(fd: Fd, value: u32) -> io::Result<()> {
+    backend::net::sockopt::set_ipv6_multicast_if(fd.as_fd(), value)
+}
+
+/// `getsockopt(fd, IPPROTO_IPV6, IPV6_MULTICAST_IF)`
+///
+/// See the [module-level documentation] for more.
+///
+/// [module-level documentation]: self#references-for-get_ip_-and-set_ip_-functions
+#[inline]
+#[doc(alias = "IPV6_MULTICAST_IF")]
+pub fn ipv6_multicast_if<Fd: AsFd>(fd: Fd) -> io::Result<u32> {
+    backend::net::sockopt::ipv6_multicast_if(fd.as_fd())
+}
+
 /// `setsockopt(fd, IPPROTO_IP, IP_MULTICAST_LOOP, value)`
 ///
 /// See the [module-level documentation] for more.
@@ -798,7 +869,7 @@ pub fn set_ip_add_membership_with_ifindex<Fd: AsFd>(
     fd: Fd,
     multiaddr: &Ipv4Addr,
     address: &Ipv4Addr,
-    ifindex: i32,
+    ifindex: u32,
 ) -> io::Result<()> {
     backend::net::sockopt::set_ip_add_membership_with_ifindex(
         fd.as_fd(),
@@ -907,7 +978,7 @@ pub fn set_ip_drop_membership_with_ifindex<Fd: AsFd>(
     fd: Fd,
     multiaddr: &Ipv4Addr,
     address: &Ipv4Addr,
-    ifindex: i32,
+    ifindex: u32,
 ) -> io::Result<()> {
     backend::net::sockopt::set_ip_drop_membership_with_ifindex(
         fd.as_fd(),
diff --git a/tests/net/sockopt.rs b/tests/net/sockopt.rs
@@ -10,7 +10,7 @@ use rustix::io;
 ))]
 use rustix::net::ipproto;
 use rustix::net::{sockopt, AddressFamily, SocketType};
-use std::time::Duration;
+use std::{net::Ipv4Addr, time::Duration};
 
 // Test `socket` socket options.
 fn test_sockopts_socket(s: &OwnedFd) {
@@ -486,3 +486,72 @@ fn test_sockopts_ipv6() {
 
     test_sockopts_tcp(&s);
 }
+
+#[test]
+fn test_sockopts_multicast_ifv4() {
+    crate::init();
+
+    let s = rustix::net::socket(AddressFamily::INET, SocketType::DGRAM, None).unwrap();
+
+    // Set a ipv4 interface
+    match sockopt::set_ip_multicast_if(&s, &Ipv4Addr::LOCALHOST) {
+        Ok(_) => {
+            assert_eq!(sockopt::ip_multicast_if(&s).unwrap(), Ipv4Addr::LOCALHOST);
+        }
+        Err(e) if e.to_string().contains("Protocol not available") => {
+            // Skip test on unsupported platforms
+        }
+        Err(e) => panic!("{e}"),
+    }
+}
+
+#[cfg(linux_kernel)]
+#[test]
+fn test_sockopts_multicast_if_with_ifindex() {
+    crate::init();
+
+    let s = rustix::net::socket(AddressFamily::INET, SocketType::DGRAM, None).unwrap();
+
+    let fd = rustix::net::socket_with(
+        AddressFamily::INET,
+        SocketType::DGRAM,
+        rustix::net::SocketFlags::CLOEXEC,
+        None,
+    )
+    .unwrap();
+    let index = rustix::net::netdevice::name_to_index(&fd, "lo").unwrap();
+
+    // Set a ipv4 interface
+    match sockopt::set_ip_multicast_if_with_ifindex(
+        &s,
+        &Ipv4Addr::new(224, 254, 0, 0),
+        &Ipv4Addr::UNSPECIFIED,
+        index,
+    ) {
+        Ok(_) => {
+            assert_eq!(sockopt::ip_multicast_if(&s).unwrap(), Ipv4Addr::UNSPECIFIED);
+        }
+        Err(e) if e.to_string().contains("Protocol not available") => {
+            // Skip test on unsupported platforms
+        }
+        Err(e) => panic!("{e}"),
+    }
+}
+
+#[test]
+fn test_sockopts_multicast_ifv6() {
+    crate::init();
+
+    let s = rustix::net::socket(AddressFamily::INET6, SocketType::DGRAM, None).unwrap();
+
+    // Set a ipv6 interface
+    match sockopt::set_ipv6_multicast_if(&s, 1) {
+        Ok(_) => {
+            assert_eq!(sockopt::ipv6_multicast_if(&s).unwrap(), 1);
+        }
+        Err(e) if e.to_string().contains("Protocol not available") => {
+            // Skip test on unsupported platforms
+        }
+        Err(e) => panic!("{e}"),
+    }
+}
