Update ipc/ directory to use mach_port_name_t

Make it explicit where we use port names versus actual ports. For the 64
bit kernel, port names and ports are of different size so this corrects
the syscall arguments and internal structs to have the right size.

This patch also uncovered several issues we need to solve to make
GNUMach work well on 64 bits. First, the mach_msg call will receive 4
byte port names while the kernel "thinks" they are 8 bytes, which will
be a problem. Also, when we send a message, the kernel translates the
port names into port pointers in the message copied from user space.
This also won't work on 64 bits. In this patch, I added several TODOs to fix
the issues later.
Message-Id: <Y4cCzNmc6vC4bjsX@viriathus>

1 files changed, 37 insertions, 21 deletions

diff --git a/ipc/ipc_kmsg.c b/ipc/ipc_kmsg.c
index 4f5ffb5f..1e00b355 100644
--- a/ipc/ipc_kmsg.c
+++ b/ipc/ipc_kmsg.c
@@ -674,11 +674,21 @@ mach_msg_return_t
 ipc_kmsg_copyin_header(
 	mach_msg_header_t 	*msg,
 	ipc_space_t 		space,
-	mach_port_t 		notify)
+	mach_port_name_t 	notify)
 {
 	mach_msg_bits_t mbits = msg->msgh_bits &~ MACH_MSGH_BITS_CIRCULAR;
-	mach_port_t dest_name = msg->msgh_remote_port;
-	mach_port_t reply_name = msg->msgh_local_port;
+	/*
+	 * TODO: For 64 bits, msgh_remote_port as written by user space
+	 * is 4 bytes long but here we assume it is the same size as a pointer.
+	 * When copying the message to the kernel, we need to perform the
+	 * conversion so that port names are parsed correctly.
+	 *
+	 * When copying the message out of the kernel to user space, we also need
+	 * to be careful with the reverse translation.
+	 */
+
+	mach_port_name_t dest_name = (mach_port_name_t)msg->msgh_remote_port;
+	mach_port_name_t reply_name = (mach_port_name_t)msg->msgh_local_port;
 	kern_return_t kr;
 
 #ifndef MIGRATING_THREADS
@@ -916,7 +926,7 @@ ipc_kmsg_copyin_header(
 
 	if (dest_name == reply_name) {
 		ipc_entry_t entry;
-		mach_port_t name = dest_name;
+		mach_port_name_t name = dest_name;
 
 		/*
 		 *	Destination and reply ports are the same!
@@ -1443,7 +1453,7 @@ ipc_kmsg_copyin_body(
 				((mach_msg_type_t*)type)->msgt_name = newname;
 
 			for (i = 0; i < number; i++) {
-				mach_port_t port = (mach_port_t) objects[i];
+				mach_port_name_t port = (mach_port_name_t) objects[i];
 				ipc_object_t object;
 
 				if (!MACH_PORT_VALID(port))
@@ -1464,6 +1474,9 @@ ipc_kmsg_copyin_body(
 					kmsg->ikm_header.msgh_bits |=
 						MACH_MSGH_BITS_CIRCULAR;
 
+				/* TODO: revisit this for 64 bits since the size of
+				 * mach_port_name_t is not the same as a pointer size.
+				 */
 				objects[i] = object;
 			}
 
@@ -1507,7 +1520,7 @@ ipc_kmsg_copyin(
 	ipc_kmsg_t 	kmsg,
 	ipc_space_t 	space,
 	vm_map_t 	map,
-	mach_port_t 	notify)
+	mach_port_name_t notify)
 {
 	mach_msg_return_t mr;
 
@@ -1700,7 +1713,7 @@ mach_msg_return_t
 ipc_kmsg_copyout_header(
 	mach_msg_header_t 	*msg,
 	ipc_space_t 		space,
-	mach_port_t 		notify)
+	mach_port_name_t 		notify)
 {
 	mach_msg_bits_t mbits = msg->msgh_bits;
 	ipc_port_t dest = (ipc_port_t) msg->msgh_remote_port;
@@ -1712,7 +1725,7 @@ ipc_kmsg_copyout_header(
 
 	if (notify == MACH_PORT_NULL) switch (MACH_MSGH_BITS_PORTS(mbits)) {
 	    case MACH_MSGH_BITS(MACH_MSG_TYPE_PORT_SEND, 0): {
-		mach_port_t dest_name;
+		mach_port_name_t dest_name;
 		ipc_port_t nsrequest;
 		unsigned long payload;
 
@@ -1765,7 +1778,7 @@ ipc_kmsg_copyout_header(
 				MACH_MSG_TYPE_PORT_SEND_ONCE): {
 		ipc_entry_t entry;
 		ipc_port_t reply = (ipc_port_t) msg->msgh_local_port;
-		mach_port_t dest_name, reply_name;
+		mach_port_name_t dest_name, reply_name;
 		ipc_port_t nsrequest;
 		unsigned long payload;
 
@@ -1868,7 +1881,7 @@ ipc_kmsg_copyout_header(
 	    }
 
 	    case MACH_MSGH_BITS(MACH_MSG_TYPE_PORT_SEND_ONCE, 0): {
-		mach_port_t dest_name;
+		mach_port_name_t dest_name;
 		unsigned long payload;
 
 		/* receiving a reply message */
@@ -1922,7 +1935,7 @@ ipc_kmsg_copyout_header(
 	mach_msg_type_name_t dest_type = MACH_MSGH_BITS_REMOTE(mbits);
 	mach_msg_type_name_t reply_type = MACH_MSGH_BITS_LOCAL(mbits);
 	ipc_port_t reply = (ipc_port_t) msg->msgh_local_port;
-	mach_port_t dest_name, reply_name;
+	mach_port_name_t dest_name, reply_name;
 	unsigned long payload;
 
 	if (IP_VALID(reply)) {
@@ -2111,7 +2124,7 @@ ipc_kmsg_copyout_header(
 		ip_lock(dest);
 		is_read_unlock(space);
 
-		reply_name = (mach_port_t) reply;
+		reply_name = (mach_port_name_t) reply;
 	}
 
 	/*
@@ -2230,10 +2243,10 @@ ipc_kmsg_copyout_object(
 	ipc_space_t 		space,
 	ipc_object_t 		object,
 	mach_msg_type_name_t 	msgt_name,
-	mach_port_t 		*namep)
+	mach_port_name_t 	*namep)
 {
 	if (!IO_VALID(object)) {
-		*namep = (mach_port_t) object;
+		*namep = (mach_port_name_t) object;
 		return MACH_MSG_SUCCESS;
 	}
 
@@ -2393,7 +2406,7 @@ ipc_kmsg_copyout_body(
 		is_port = MACH_MSG_TYPE_PORT_ANY(name);
 
 		if (is_port) {
-			mach_port_t *objects;
+			ipc_object_t *objects;
 			mach_msg_type_number_t i;
 
 			if (!is_inline && (length != 0)) {
@@ -2406,7 +2419,7 @@ ipc_kmsg_copyout_body(
 				}
 			}
 
-			objects = (mach_port_t *)
+			objects = (ipc_object_t *)
 				(is_inline ? saddr : * (vm_offset_t *) saddr);
 
 			/* copyout port rights carried in the message */
@@ -2415,8 +2428,11 @@ ipc_kmsg_copyout_body(
 				ipc_object_t object =
 					(ipc_object_t) objects[i];
 
+				/* TODO: revisit this for 64 bits since the size of
+				 * mach_port_name_t is not the same as a pointer size.
+				 */
 				mr |= ipc_kmsg_copyout_object(space, object,
-							name, &objects[i]);
+							name, (mach_port_name_t *)&objects[i]);
 			}
 		}
 
@@ -2498,7 +2514,7 @@ ipc_kmsg_copyout(
 	ipc_kmsg_t 	kmsg,
 	ipc_space_t 	space,
 	vm_map_t 	map,
-	mach_port_t 	notify)
+	mach_port_name_t 	notify)
 {
 	mach_msg_bits_t mbits = kmsg->ikm_header.msgh_bits;
 	mach_msg_return_t mr;
@@ -2547,7 +2563,7 @@ ipc_kmsg_copyout_pseudo(
 	ipc_object_t reply = (ipc_object_t) kmsg->ikm_header.msgh_local_port;
 	mach_msg_type_name_t dest_type = MACH_MSGH_BITS_REMOTE(mbits);
 	mach_msg_type_name_t reply_type = MACH_MSGH_BITS_LOCAL(mbits);
-	mach_port_t dest_name, reply_name;
+	mach_port_name_t dest_name, reply_name;
 	mach_msg_return_t mr;
 
 	assert(IO_VALID(dest));
@@ -2585,7 +2601,7 @@ ipc_kmsg_copyout_dest(
 	ipc_object_t reply = (ipc_object_t) kmsg->ikm_header.msgh_local_port;
 	mach_msg_type_name_t dest_type = MACH_MSGH_BITS_REMOTE(mbits);
 	mach_msg_type_name_t reply_type = MACH_MSGH_BITS_LOCAL(mbits);
-	mach_port_t dest_name, reply_name;
+	mach_port_name_t dest_name, reply_name;
 
 	assert(IO_VALID(dest));
 
@@ -2603,7 +2619,7 @@ ipc_kmsg_copyout_dest(
 		ipc_object_destroy(reply, reply_type);
 		reply_name = MACH_PORT_NULL;
 	} else
-		reply_name = (mach_port_t) reply;
+		reply_name = (mach_port_name_t) reply;
 
 	kmsg->ikm_header.msgh_bits = (MACH_MSGH_BITS_OTHER(mbits) |
 				      MACH_MSGH_BITS(reply_type, dest_type));