Add SockProtocol variants for ICMP{,v6}

Author: gnaaman-dn

CHANGELOG.md

@@ -29,6 +29,8 @@ This project adheres to [Semantic Versioning](https://semver.org/).
 - Removed `flock` from `::nix::fcntl` on Solaris. ([#2082](https://github.com/nix-rust/nix/pull/2082))
 - Use I/O safety with `copy_file_range`, and expose it on FreeBSD.
   (#[1906](https://github.com/nix-rust/nix/pull/1906))
+- Added `Icmp` and `IcmpV6` to `SockProtocol`.
+  (#[2103](https://github.com/nix-rust/nix/pull/2103))
 
 ### Changed
 

src/sys/socket/mod.rs

@@ -132,11 +132,6 @@ pub enum SockProtocol {
     Udp = libc::IPPROTO_UDP,
     /// Raw sockets ([raw(7)](https://man7.org/linux/man-pages/man7/raw.7.html))
     Raw = libc::IPPROTO_RAW,
-    /// Allows applications and other KEXTs to be notified when certain kernel events occur
-    /// ([ref](https://developer.apple.com/library/content/documentation/Darwin/Conceptual/NKEConceptual/control/control.html))
-    #[cfg(any(target_os = "ios", target_os = "macos"))]
-    #[cfg_attr(docsrs, doc(cfg(all())))]
-    KextEvent = libc::SYSPROTO_EVENT,
     /// Allows applications to configure and control a KEXT
     /// ([ref](https://developer.apple.com/library/content/documentation/Darwin/Conceptual/NKEConceptual/control/control.html))
     #[cfg(any(target_os = "ios", target_os = "macos"))]
@@ -221,20 +216,33 @@ pub enum SockProtocol {
     #[cfg(any(target_os = "android", target_os = "linux"))]
     #[cfg_attr(docsrs, doc(cfg(all())))]
     EthAll = (libc::ETH_P_ALL as u16).to_be() as i32,
+    /// ICMP protocol ([icmp(7)](https://man7.org/linux/man-pages/man7/icmp.7.html))
+    Icmp = libc::IPPROTO_ICMP,
+    /// ICMPv6 protocol (ICMP over IPv6)
+    IvmpV6 = libc::IPPROTO_ICMPV6,
+}
+
+impl SockProtocol {
     /// The Controller Area Network raw socket protocol
     /// ([ref](https://docs.kernel.org/networking/can.html#how-to-use-socketcan))
     #[cfg(target_os = "linux")]
     #[cfg_attr(docsrs, doc(cfg(all())))]
-    CanRaw = libc::CAN_RAW,
-}
+    #[allow(non_upper_case_globals)]
+    pub const CanRaw: SockProtocol = SockProtocol::Icmp; // Matches libc::CAN_RAW
 
-impl SockProtocol {
     /// The Controller Area Network broadcast manager protocol
     /// ([ref](https://docs.kernel.org/networking/can.html#how-to-use-socketcan))
     #[cfg(target_os = "linux")]
     #[cfg_attr(docsrs, doc(cfg(all())))]
     #[allow(non_upper_case_globals)]
     pub const CanBcm: SockProtocol = SockProtocol::NetlinkUserSock; // Matches libc::CAN_BCM
+
+    /// Allows applications and other KEXTs to be notified when certain kernel events occur
+    /// ([ref](https://developer.apple.com/library/content/documentation/Darwin/Conceptual/NKEConceptual/control/control.html))
+    #[cfg(any(target_os = "ios", target_os = "macos"))]
+    #[cfg_attr(docsrs, doc(cfg(all())))]
+    #[allow(non_upper_case_globals)]
+    pub const KextEvent: SockProtocol = SockProtocol::Icmp;  // Matches libc::SYSPROTO_EVENT
 }
 #[cfg(any(target_os = "android", target_os = "linux"))]
 libc_bitflags! {
@@ -2441,4 +2449,15 @@ mod tests {
         )
         .expect("Failed to open routing socket");
     }
+    #[test]
+    fn sock_protocol_constant_matches() {
+        #[cfg(target_os = "linux")]
+        assert_eq!(super::SockProtocol::CanRaw as libc::c_int, libc::CAN_RAW);
+
+        #[cfg(target_os = "linux")]
+        assert_eq!(super::SockProtocol::CanBcm as libc::c_int, libc::CAN_BCM);
+
+        #[cfg(any(target_os = "ios", target_os = "macos"))]
+        assert_eq!(super::SockProtocol::KextEvent as libc::c_int, libc::SYSPROTO_EVENT);
+    }
 }

test/sys/test_socket.rs

@@ -2685,3 +2685,32 @@ pub fn test_txtime() {
     recvmsg::<()>(rsock.as_raw_fd(), &mut iov2, None, MsgFlags::empty())
         .unwrap();
 }
+
+#[test]
+pub fn test_icmp() {
+    // _ICMP_ECHO_REQUEST     = 8
+    // _ICMP_ECHO_REPLY       = 0
+    use nix::sys::socket::{
+        bind, recv, sendto, setsockopt, socket, sockopt, ControlMessage,
+        MsgFlags, SockFlag, SockType, SockaddrIn, SockProtocol
+    };
+
+    const ECHO_REQUEST: &[u8] = &[
+        // ICMP Type = Echo Request
+        0x08,
+        // ICMP Code = 0 (N/A)
+        0x00,
+        // Checksum
+        0x8f, 0x53,
+        // Identifier
+        0x12, 0x34,
+        // Sequence Number
+        0x56, 0x78,
+    ];
+
+    let sock = socket(AddressFamily::Inet, SockType::Raw, SockFlag::empty(), SockProtocol::Icmp).unwrap();
+    let sock_addr = SockaddrIn::new(127, 0, 0, 1, 0);
+
+    let rc = sendto(sock.as_raw_fd(), ECHO_REQUEST, &sock_addr, MsgFlags::empty()).unwrap();
+    assert_eq!(rc, ECHO_REQUEST.len());
+}