Auto merge of #478 - conradev:sys-control, r=fiveop

Add support for system control sockets for XNU

I added support for macOS and iOS system sockets, which can be used to control the kernel as described [here](https://developer.apple.com/library/content/documentation/Darwin/Conceptual/NKEConceptual/control/control.html).

To do this, I had to add in support for `ioctl` on those platforms, so I added in `ioctl` support for all BSD-based platforms. The API seems to be the same between [xnu](https://opensource.apple.com/source/xnu/xnu-3248.60.10/bsd/sys/ioccom.h.auto.html), [FreeBSD](https://github.com/freebsd/freebsd/blob/master/sys/sys/ioccom.h), [NetBSD](https://ftp.netbsd.org/pub/NetBSD/NetBSD-current/src/sys/sys/ioccom.h), [OpenBSD](http://cvsweb.openbsd.org/cgi-bin/cvsweb/src/sys/sys/ioccom.h?rev=1.5&content-type=text/x-cvsweb-markup) and [Dragonfly BSD](http://gitweb.dragonflybsd.org/dragonfly.git/blob/HEAD:/sys/sys/ioccom.h).

I added a test that runs on macOS and iOS for the functionality. Let me know if I need to make any changes!

2 files changed, 104 insertions, 36 deletions

diff --git a/test/sys/test_ioctl.rs b/test/sys/test_ioctl.rs
index 94eca447..1d9fbcc8 100644
--- a/test/sys/test_ioctl.rs
+++ b/test/sys/test_ioctl.rs
@@ -1,9 +1,7 @@
 #![allow(dead_code)]
 
-#![cfg(target_os = "linux")] // no ioctl support for osx yet
-
 // Simple tests to ensure macro generated fns compile
-ioctl!(bad do_bad with 0x1234);
+ioctl!(do_bad with 0x1234);
 ioctl!(none do_none with 0, 0);
 ioctl!(read read_test with 0, 0; u32);
 ioctl!(write write_test with 0, 0; u64);
@@ -15,44 +13,97 @@ ioctl!(readwrite buf readwritebuf_test with 0, 0; u32);
 // See C code for source of values for op calculations:
 // https://gist.github.com/posborne/83ea6880770a1aef332e
 
-#[test]
-fn test_op_none() {
-    assert_eq!(io!(b'q', 10), 0x0000710A);
-    assert_eq!(io!(b'a', 255), 0x000061FF);
-}
+#[cfg(any(target_os = "linux", target_os = "android"))]
+mod linux {
+    #[test]
+    fn test_op_none() {
+        assert_eq!(io!(b'q', 10), 0x0000710A);
+        assert_eq!(io!(b'a', 255), 0x000061FF);
+    }
 
-#[test]
-fn test_op_write() {
-    assert_eq!(iow!(b'z', 10, 1), 0x40017A0A);
-    assert_eq!(iow!(b'z', 10, 512), 0x42007A0A);
-}
+    #[test]
+    fn test_op_write() {
+        assert_eq!(iow!(b'z', 10, 1), 0x40017A0A);
+        assert_eq!(iow!(b'z', 10, 512), 0x42007A0A);
+    }
 
-#[cfg(target_pointer_width = "64")]
-#[test]
-fn test_op_write_64() {
-    assert_eq!(iow!(b'z', 10, (1 as u64) << 32), 0x40007A0A);
-}
+    #[cfg(target_pointer_width = "64")]
+    #[test]
+    fn test_op_write_64() {
+        assert_eq!(iow!(b'z', 10, (1 as u64) << 32), 0x40007A0A);
+    }
 
-#[test]
-fn test_op_read() {
-    assert_eq!(ior!(b'z', 10, 1), 0x80017A0A);
-    assert_eq!(ior!(b'z', 10, 512), 0x82007A0A);
-}
+    #[test]
+    fn test_op_read() {
+        assert_eq!(ior!(b'z', 10, 1), 0x80017A0A);
+        assert_eq!(ior!(b'z', 10, 512), 0x82007A0A);
+    }
 
-#[cfg(target_pointer_width = "64")]
-#[test]
-fn test_op_read_64() {
-    assert_eq!(ior!(b'z', 10, (1 as u64) << 32), 0x80007A0A);
-}
+    #[cfg(target_pointer_width = "64")]
+    #[test]
+    fn test_op_read_64() {
+        assert_eq!(ior!(b'z', 10, (1 as u64) << 32), 0x80007A0A);
+    }
+
+    #[test]
+    fn test_op_read_write() {
+        assert_eq!(iorw!(b'z', 10, 1), 0xC0017A0A);
+        assert_eq!(iorw!(b'z', 10, 512), 0xC2007A0A);
+    }
 
-#[test]
-fn test_op_read_write() {
-    assert_eq!(iorw!(b'z', 10, 1), 0xC0017A0A);
-    assert_eq!(iorw!(b'z', 10, 512), 0xC2007A0A);
+    #[cfg(target_pointer_width = "64")]
+    #[test]
+    fn test_op_read_write_64() {
+        assert_eq!(iorw!(b'z', 10, (1 as u64) << 32), 0xC0007A0A);
+    } 
 }
 
-#[cfg(target_pointer_width = "64")]
-#[test]
-fn test_op_read_write_64() {
-    assert_eq!(iorw!(b'z', 10, (1 as u64) << 32), 0xC0007A0A);
+#[cfg(any(target_os = "macos",
+          target_os = "ios",
+          target_os = "netbsd",
+          target_os = "openbsd",
+          target_os = "freebsd",
+          target_os = "dragonfly"))]
+mod bsd {
+    #[test]
+    fn test_op_none() {
+        assert_eq!(io!(b'q', 10), 0x2000710A);
+        assert_eq!(io!(b'a', 255), 0x200061FF);
+    }
+
+    #[test]
+    fn test_op_write() {
+        assert_eq!(iow!(b'z', 10, 1), 0x80017A0A);
+        assert_eq!(iow!(b'z', 10, 512), 0x82007A0A);
+    }
+
+    #[cfg(target_pointer_width = "64")]
+    #[test]
+    fn test_op_write_64() {
+        assert_eq!(iow!(b'z', 10, (1 as u64) << 32), 0x80007A0A);
+    }
+
+    #[test]
+    fn test_op_read() {
+        assert_eq!(ior!(b'z', 10, 1), 0x40017A0A);
+        assert_eq!(ior!(b'z', 10, 512), 0x42007A0A);
+    }
+
+    #[cfg(target_pointer_width = "64")]
+    #[test]
+    fn test_op_read_64() {
+        assert_eq!(ior!(b'z', 10, (1 as u64) << 32), 0x40007A0A);
+    }
+
+    #[test]
+    fn test_op_read_write() {
+        assert_eq!(iorw!(b'z', 10, 1), 0xC0017A0A);
+        assert_eq!(iorw!(b'z', 10, 512), 0xC2007A0A);
+    }
+
+    #[cfg(target_pointer_width = "64")]
+    #[test]
+    fn test_op_read_write_64() {
+        assert_eq!(iorw!(b'z', 10, (1 as u64) << 32), 0xC0007A0A);
+    } 
 }
diff --git a/test/sys/test_socket.rs b/test/sys/test_socket.rs
index 9f4b4278..b5465aa0 100644
--- a/test/sys/test_socket.rs
+++ b/test/sys/test_socket.rs
@@ -180,3 +180,20 @@ pub fn test_unixdomain() {
 
     assert_eq!(&buf[..], b"hello");
 }
+
+// Test creating and using named system control sockets
+#[cfg(any(target_os = "macos", target_os = "ios"))]
+#[test]
+pub fn test_syscontrol() {
+    use nix::{Errno, Error};
+    use nix::sys::socket::{AddressFamily, SockType, SockFlag};
+    use nix::sys::socket::{socket, SockAddr};
+    use nix::sys::socket::SYSPROTO_CONTROL;
+
+    let fd = socket(AddressFamily::System, SockType::Datagram, SockFlag::empty(), SYSPROTO_CONTROL).expect("socket failed");
+    let _sockaddr = SockAddr::new_sys_control(fd, "com.apple.net.utun_control", 0).expect("resolving sys_control name failed");
+    assert_eq!(SockAddr::new_sys_control(fd, "foo.bar.lol", 0).err(), Some(Error::Sys(Errno::ENOENT)));
+
+    // requires root privileges
+    // connect(fd, &sockaddr).expect("connect failed");
+}