feat: Add glibc::SOF_TIMESTAMPING_* support

CHANGELOG.md

@@ -3,9 +3,14 @@
 All notable changes to this project will be documented in this file.
 This project adheres to [Semantic Versioning](https://semver.org/).
 
-## [0.23.0] - 2021-09-28
+
+## [Unreleased] - ReleaseDate
 ### Added
+- Added the `SO_TIMESTAMPING` support
+  (#[1547](https://github.com/nix-rust/nix/pull/1547))
 
+## [0.23.0] - 2021-09-28
+### Added
 - Added the `LocalPeerCred` sockopt.
   (#[1482](https://github.com/nix-rust/nix/pull/1482))
 - Added `TimeSpec::from_duration` and `TimeSpec::from_timespec`

src/sys/socket/mod.rs

@@ -170,6 +170,28 @@ pub enum SockProtocol {
     NetlinkCrypto = libc::NETLINK_CRYPTO,
 }
 
+#[cfg(any(target_os = "linux"))]
+libc_bitflags! {
+    /// Configuration flags for `SO_TIMESTAMPING` interface
+    ///
+    /// For use with [`Timestamping`][sockopt::Timestamping].
+    /// [Further reading](https://www.kernel.org/doc/html/latest/networking/timestamping.html)
+    pub struct TimestampingFlag: c_uint {
+        /// Report any software timestamps when available.
+        SOF_TIMESTAMPING_SOFTWARE;
+        /// Report hardware timestamps as generated by SOF_TIMESTAMPING_TX_HARDWARE when available.
+        SOF_TIMESTAMPING_RAW_HARDWARE;
+        /// Collect transmiting timestamps as reported by hardware
+        SOF_TIMESTAMPING_TX_HARDWARE;
+        /// Collect transmiting timestamps as reported by software
+        SOF_TIMESTAMPING_TX_SOFTWARE;
+        /// Collect receiving timestamps as reported by hardware
+        SOF_TIMESTAMPING_RX_HARDWARE;
+        /// Collect receiving timestamps as reported by software
+        SOF_TIMESTAMPING_RX_SOFTWARE;
+    }
+}
+
 libc_bitflags!{
     /// Additional socket options
     pub struct SockFlag: c_int {
@@ -591,6 +613,11 @@ pub enum ControlMessageOwned {
     /// # }
     /// ```
     ScmTimestamp(TimeVal),
+    /// A set of nanosecond resolution timestamps
+    ///
+    /// [Further reading](https://www.kernel.org/doc/html/latest/networking/timestamping.html)
+    #[cfg(all(target_os = "linux"))]
+    ScmTimestampsns(Timestamps),
     /// Nanoseconds resolution timestamp
     ///
     /// [Further reading](https://www.kernel.org/doc/html/latest/networking/timestamping.html)
@@ -666,6 +693,18 @@ pub enum ControlMessageOwned {
     Unknown(UnknownCmsg),
 }
 
+/// For representing packet timestamps via `SO_TIMESTAMPING` interface
+#[cfg(all(target_os = "linux"))]
+#[derive(Copy, Clone, Debug, Eq, PartialEq)]
+pub struct Timestamps {
+    /// software based timestamp, usually one containing data
+    pub system: TimeSpec,
+    /// legacy timestamp, usually empty
+    pub hw_trans: TimeSpec,
+    /// hardware based timestamp
+    pub hw_raw: TimeSpec,
+}
+
 impl ControlMessageOwned {
     /// Decodes a `ControlMessageOwned` from raw bytes.
     ///
@@ -710,6 +749,18 @@ impl ControlMessageOwned {
                 let ts: libc::timespec = ptr::read_unaligned(p as *const _);
                 ControlMessageOwned::ScmTimestampns(TimeSpec::from(ts))
             }
+            #[cfg(all(target_os = "linux"))]
+            (libc::SOL_SOCKET, libc::SCM_TIMESTAMPING) => {
+                let tp = p as *const libc::timespec;
+                let ts: libc::timespec = ptr::read_unaligned(tp);
+                let system = TimeSpec::from(ts);
+                let ts: libc::timespec = ptr::read_unaligned(tp.add(1));
+                let hw_trans = TimeSpec::from(ts);
+                let ts: libc::timespec = ptr::read_unaligned(tp.add(2));
+                let hw_raw = TimeSpec::from(ts);
+                let timestamping = Timestamps { system, hw_trans, hw_raw };
+                ControlMessageOwned::ScmTimestampsns(timestamping)
+            }
             #[cfg(any(
                 target_os = "android",
                 target_os = "freebsd",

src/sys/socket/sockopt.rs

@@ -16,7 +16,7 @@ use std::os::unix::ffi::OsStrExt;
 
 // Constants
 // TCP_CA_NAME_MAX isn't defined in user space include files
-#[cfg(any(target_os = "freebsd", target_os = "linux"))] 
+#[cfg(any(target_os = "freebsd", target_os = "linux"))]
 const TCP_CA_NAME_MAX: usize = 16;
 
 /// Helper for implementing `SetSockOpt` for a given socket option. See
@@ -432,7 +432,12 @@ sockopt_impl!(
     #[allow(missing_docs)]
     // Not documented by Linux!
     Ip6tOriginalDst, GetOnly, libc::SOL_IPV6, libc::IP6T_SO_ORIGINAL_DST, libc::sockaddr_in6);
-sockopt_impl!( 
+#[cfg(any(target_os = "linux"))]
+sockopt_impl!(
+    /// Specifies exact type of timestamping information collected by the kernel
+    /// [Further reading](https://www.kernel.org/doc/html/latest/networking/timestamping.html)
+    Timestamping, Both, libc::SOL_SOCKET, libc::SO_TIMESTAMPING, super::TimestampingFlag);
+sockopt_impl!(
     /// Enable or disable the receiving of the `SO_TIMESTAMP` control message.
     ReceiveTimestamp, Both, libc::SOL_SOCKET, libc::SO_TIMESTAMP, bool);
 #[cfg(all(target_os = "linux"))]
@@ -463,7 +468,7 @@ sockopt_impl!(
     /// Enable or disable the receiving of the `SCM_CREDENTIALS` control
     /// message.
     PassCred, Both, libc::SOL_SOCKET, libc::SO_PASSCRED, bool);
-#[cfg(any(target_os = "freebsd", target_os = "linux"))] 
+#[cfg(any(target_os = "freebsd", target_os = "linux"))]
 sockopt_impl!(
     /// This option allows the caller to set the TCP congestion control
     /// algorithm to be used,  on a per-socket basis.

test/sys/test_socket.rs

@@ -57,6 +57,64 @@ pub fn test_inetv4_addr_roundtrip_sockaddr_storage_to_addr() {
     assert_eq!(from_storage, sockaddr);
 }
 
+#[cfg(any(target_os = "linux"))]
+#[cfg_attr(qemu, ignore)]
+#[test]
+pub fn test_timestamping() {
+    use nix::sys::socket::{
+        recvmsg, sendmsg, setsockopt, socket, sockopt::Timestamping, ControlMessageOwned, MsgFlags,
+        SockFlag, SockType, TimestampingFlag,
+    };
+    use nix::sys::uio::IoVec;
+
+    let std_sa = SocketAddr::from_str("127.0.0.1:6790").unwrap();
+    let inet_addr = InetAddr::from_std(&std_sa);
+    let sock_addr = SockAddr::new_inet(inet_addr);
+
+    let ssock = socket(
+        AddressFamily::Inet,
+        SockType::Datagram,
+        SockFlag::empty(),
+        None,
+    )
+    .expect("send socket failed");
+
+    let rsock = socket(
+        AddressFamily::Inet,
+        SockType::Datagram,
+        SockFlag::empty(),
+        None,
+    )
+    .unwrap();
+    nix::sys::socket::bind(rsock, &sock_addr).unwrap();
+
+    setsockopt(rsock, Timestamping, &TimestampingFlag::all()).unwrap();
+
+    let sbuf = [0u8; 2048];
+    let mut rbuf = [0u8; 2048];
+    let flags = MsgFlags::empty();
+    let iov1 = [IoVec::from_slice(&sbuf)];
+    let iov2 = [IoVec::from_mut_slice(&mut rbuf)];
+    let mut cmsg = cmsg_space!(nix::sys::socket::Timestamps);
+    sendmsg(ssock, &iov1, &[], flags, Some(&sock_addr)).unwrap();
+    let recv = recvmsg(rsock, &iov2, Some(&mut cmsg), flags).unwrap();
+
+    let mut ts = None;
+    for c in recv.cmsgs() {
+        if let ControlMessageOwned::ScmTimestampsns(timestamps) = c {
+            ts = Some(timestamps.system);
+        }
+    }
+    let ts = ts.expect("ScmTimestampns is present");
+    let sys_time = ::nix::time::clock_gettime(::nix::time::ClockId::CLOCK_REALTIME).unwrap();
+    let diff = if ts > sys_time {
+        ts - sys_time
+    } else {
+        sys_time - ts
+    };
+    assert!(std::time::Duration::from(diff).as_secs() < 60);
+}
+
 #[test]
 pub fn test_inetv6_addr_to_sock_addr() {
     let port: u16 = 3000;