ScmCredentials now wraps UnixCredentials instead of libc::ucred

Author: asomers

CHANGELOG.md

@@ -27,6 +27,7 @@ This project adheres to [Semantic Versioning](http://semver.org/).
 - Added `User::from_uid`, `User::from_name`, `User::from_gid` and
   `Group::from_name`,
   ([#1139](https://github.com/nix-rust/nix/pull/1139))
+
 - Added `linkat`
   ([#1101](https://github.com/nix-rust/nix/pull/1101))
 
@@ -39,6 +40,10 @@ This project adheres to [Semantic Versioning](http://semver.org/).
 ### Changed
 - `sys::termios::BaudRate` now implements `TryFrom<speed_t>` instead of
   `From<speed_t>`.  The old `From` implementation would panic on failure.
+
+- `sys::socket::ControlMessage::ScmCredentials` and
+  `sys::socket::ControlMessageOwned::ScmCredentials` now wrap `UnixCredentials`
+  rather than `libc::ucred`.
   ([#1159](https://github.com/nix-rust/nix/pull/1159))
 
 - `sys::socket::recvmsg` now takes a plain `Vec` instead of a `CmsgBuffer`

src/sys/socket/mod.rs

@@ -190,7 +190,7 @@ cfg_if! {
         /// Unix credentials of the sending process.
         ///
         /// This struct is used with the `SO_PEERCRED` ancillary message for UNIX sockets.
-        #[repr(C)]
+        #[repr(transparent)]
         #[derive(Clone, Copy, Debug, Eq, PartialEq)]
         pub struct UnixCredentials(libc::ucred);
 
@@ -368,7 +368,7 @@ pub enum ControlMessageOwned {
     /// Received version of
     /// [`ControlMessage::ScmCredentials`][#enum.ControlMessage.html#variant.ScmCredentials]
     #[cfg(any(target_os = "android", target_os = "linux"))]
-    ScmCredentials(libc::ucred),
+    ScmCredentials(UnixCredentials),
     /// A message of type `SCM_TIMESTAMP`, containing the time the
     /// packet was received by the kernel.
     ///
@@ -496,7 +496,7 @@ impl ControlMessageOwned {
             #[cfg(any(target_os = "android", target_os = "linux"))]
             (libc::SOL_SOCKET, libc::SCM_CREDENTIALS) => {
                 let cred: libc::ucred = ptr::read_unaligned(p as *const _);
-                ControlMessageOwned::ScmCredentials(cred)
+                ControlMessageOwned::ScmCredentials(cred.into())
             }
             (libc::SOL_SOCKET, libc::SCM_TIMESTAMP) => {
                 let tv: libc::timeval = ptr::read_unaligned(p as *const _);
@@ -584,10 +584,8 @@ pub enum ControlMessage<'a> {
     ///
     /// For further information, please refer to the
     /// [`unix(7)`](http://man7.org/linux/man-pages/man7/unix.7.html) man page.
-    // FIXME: When `#[repr(transparent)]` is stable, use it on `UnixCredentials`
-    // and put that in here instead of a raw ucred.
     #[cfg(any(target_os = "android", target_os = "linux"))]
-    ScmCredentials(&'a libc::ucred),
+    ScmCredentials(&'a UnixCredentials),
 
     /// Set IV for `AF_ALG` crypto API.
     ///
@@ -655,7 +653,7 @@ impl<'a> ControlMessage<'a> {
             },
             #[cfg(any(target_os = "android", target_os = "linux"))]
             ControlMessage::ScmCredentials(creds) => {
-                creds as *const libc::ucred as *const u8
+                &creds.0 as *const libc::ucred as *const u8
             }
             #[cfg(any(target_os = "android", target_os = "linux"))]
             ControlMessage::AlgSetIv(iv) => {

test/sys/test_socket.rs

@@ -561,7 +561,7 @@ fn test_scm_credentials() {
             pid: getpid().as_raw(),
             uid: getuid().as_raw(),
             gid: getgid().as_raw(),
-        };
+        }.into();
         let cmsg = ControlMessage::ScmCredentials(&cred);
         assert_eq!(sendmsg(send, &iov, &[cmsg], MsgFlags::empty(), None).unwrap(), 5);
         close(send).unwrap();
@@ -577,9 +577,9 @@ fn test_scm_credentials() {
         for cmsg in msg.cmsgs() {
             if let ControlMessageOwned::ScmCredentials(cred) = cmsg {
                 assert!(received_cred.is_none());
-                assert_eq!(cred.pid, getpid().as_raw());
-                assert_eq!(cred.uid, getuid().as_raw());
-                assert_eq!(cred.gid, getgid().as_raw());
+                assert_eq!(cred.pid(), getpid().as_raw());
+                assert_eq!(cred.uid(), getuid().as_raw());
+                assert_eq!(cred.gid(), getgid().as_raw());
                 received_cred = Some(cred);
             } else {
                 panic!("unexpected cmsg");
@@ -641,7 +641,7 @@ fn test_impl_scm_credentials_and_rights(mut space: Vec<u8>) {
             pid: getpid().as_raw(),
             uid: getuid().as_raw(),
             gid: getgid().as_raw(),
-        };
+        }.into();
         let fds = [r];
         let cmsgs = [
             ControlMessage::ScmCredentials(&cred),
@@ -669,9 +669,9 @@ fn test_impl_scm_credentials_and_rights(mut space: Vec<u8>) {
                 }
                 ControlMessageOwned::ScmCredentials(cred) => {
                     assert!(received_cred.is_none());
-                    assert_eq!(cred.pid, getpid().as_raw());
-                    assert_eq!(cred.uid, getuid().as_raw());
-                    assert_eq!(cred.gid, getgid().as_raw());
+                    assert_eq!(cred.pid(), getpid().as_raw());
+                    assert_eq!(cred.uid(), getuid().as_raw());
+                    assert_eq!(cred.gid(), getgid().as_raw());
                     received_cred = Some(cred);
                 }
                 _ => panic!("unexpected cmsg"),