Add TPROXY-related Linux things

Should close #1023.

# Conflicts:
#	src/sys/socket/mod.rs

Author: vi

src/sys/socket/mod.rs

@@ -463,6 +463,17 @@ pub enum ControlMessageOwned {
         target_os = "openbsd",
     ))]
     Ipv4RecvDstAddr(libc::in_addr),
+    #[cfg(any(
+        target_os = "linux",
+        target_os = "android",
+    ))]
+    OrigDstAddrV4(libc::sockaddr_in),
+    #[cfg(any(
+        target_os = "linux",
+        target_os = "android",
+    ))]
+    OrigDstAddrV6(libc::sockaddr_in6),
+
     /// Catch-all variant for unimplemented cmsg types.
     #[doc(hidden)]
     Unknown(UnknownCmsg),
@@ -546,6 +557,16 @@ impl ControlMessageOwned {
                 let dl = ptr::read_unaligned(p as *const libc::in_addr);
                 ControlMessageOwned::Ipv4RecvDstAddr(dl)
             },
+            #[cfg(any(target_os = "android", target_os = "linux"))]
+            (libc::IPPROTO_IP, libc::IP_ORIGDSTADDR) => {
+                let dl = ptr::read_unaligned(p as *const libc::sockaddr_in);
+                ControlMessageOwned::OrigDstAddrV4(dl)
+            },
+            #[cfg(any(target_os = "android", target_os = "linux"))]
+            (libc::IPPROTO_IPV6, libc::IPV6_ORIGDSTADDR) => {
+                let dl = ptr::read_unaligned(p as *const libc::sockaddr_in6);
+                ControlMessageOwned::OrigDstAddrV6(dl)
+            },
             (_, _) => {
                 let sl = slice::from_raw_parts(p, len);
                 let ucmsg = UnknownCmsg(*header, Vec::<u8>::from(&sl[..]));
@@ -587,6 +608,17 @@ pub enum ControlMessage<'a> {
     #[cfg(any(target_os = "android", target_os = "linux"))]
     ScmCredentials(&'a UnixCredentials),
 
+    #[cfg(any(
+        target_os = "linux",
+        target_os = "android",
+    ))]
+    OrigDstAddrV4(&'a libc::sockaddr_in),
+    #[cfg(any(
+        target_os = "linux",
+        target_os = "android",
+    ))]
+    OrigDstAddrV6(&'a libc::sockaddr_in6),
+
     /// Set IV for `AF_ALG` crypto API.
     ///
     /// For further information, please refer to the
@@ -655,6 +687,20 @@ impl<'a> ControlMessage<'a> {
             ControlMessage::ScmCredentials(creds) => {
                 &creds.0 as *const libc::ucred as *const u8
             }
+            #[cfg(any(
+                target_os = "linux",
+                target_os = "android",
+            ))]
+            ControlMessage::OrigDstAddrV4(origaddr) => {
+                origaddr as *const libc::sockaddr_in as *const u8
+            },
+            #[cfg(any(
+                target_os = "linux",
+                target_os = "android",
+            ))]
+            ControlMessage::OrigDstAddrV6(origaddr) => {
+                origaddr as *const libc::sockaddr_in6 as *const u8
+            },
             #[cfg(any(target_os = "android", target_os = "linux"))]
             ControlMessage::AlgSetIv(iv) => {
                 unsafe {
@@ -696,6 +742,20 @@ impl<'a> ControlMessage<'a> {
             ControlMessage::ScmCredentials(creds) => {
                 mem::size_of_val(creds)
             }
+            #[cfg(any(
+                target_os = "linux",
+                target_os = "android",
+            ))]
+            ControlMessage::OrigDstAddrV4(origaddr) => {
+                mem::size_of_val(origaddr)
+            },
+            #[cfg(any(
+                target_os = "linux",
+                target_os = "android",
+            ))]
+            ControlMessage::OrigDstAddrV6(origaddr) => {
+                mem::size_of_val(origaddr)
+            },
             #[cfg(any(target_os = "android", target_os = "linux"))]
             ControlMessage::AlgSetIv(iv) => {
                 mem::size_of::<libc::af_alg_iv>() + iv.len()
@@ -720,6 +780,10 @@ impl<'a> ControlMessage<'a> {
             #[cfg(any(target_os = "android", target_os = "linux"))]
             ControlMessage::AlgSetIv(_) | ControlMessage::AlgSetOp(_) |
                 ControlMessage::AlgSetAeadAssoclen(_) => libc::SOL_ALG ,
+            #[cfg(any(target_os = "android", target_os = "linux"))]
+            ControlMessage::OrigDstAddrV4(_) => libc::IPPROTO_IP,
+            #[cfg(any(target_os = "android", target_os = "linux"))]
+            ControlMessage::OrigDstAddrV6(_) => libc::IPPROTO_IPV6,
         }
     }
 
@@ -734,6 +798,14 @@ impl<'a> ControlMessage<'a> {
                 libc::ALG_SET_IV
             },
             #[cfg(any(target_os = "android", target_os = "linux"))]
+            ControlMessage::OrigDstAddrV4(_) => {
+                libc::IP_ORIGDSTADDR
+            },
+            #[cfg(any(target_os = "android", target_os = "linux"))]
+            ControlMessage::OrigDstAddrV6(_) => {
+                libc::IPV6_ORIGDSTADDR
+            },
+            #[cfg(any(target_os = "android", target_os = "linux"))]
             ControlMessage::AlgSetOp(_) => {
                 libc::ALG_SET_OP
             },

src/sys/socket/sockopt.rs

@@ -261,6 +261,10 @@ sockopt_impl!(GetOnly, OriginalDst, libc::SOL_IP, libc::SO_ORIGINAL_DST, libc::s
 sockopt_impl!(Both, ReceiveTimestamp, libc::SOL_SOCKET, libc::SO_TIMESTAMP, bool);
 #[cfg(any(target_os = "android", target_os = "linux"))]
 sockopt_impl!(Both, IpTransparent, libc::SOL_IP, libc::IP_TRANSPARENT, bool);
+#[cfg(any(target_os = "android", target_os = "linux"))]
+sockopt_impl!(Both, RecvOrigDstAddrV4, libc::SOL_IP, libc::IP_RECVORIGDSTADDR, bool);
+#[cfg(any(target_os = "android", target_os = "linux"))]
+sockopt_impl!(Both, RecvOrigDstAddrV6, libc::SOL_IPV6, libc::IPV6_RECVORIGDSTADDR, bool);
 #[cfg(target_os = "openbsd")]
 sockopt_impl!(Both, BindAny, libc::SOL_SOCKET, libc::SO_BINDANY, bool);
 #[cfg(target_os = "freebsd")]