1 files changed, 11 insertions, 4 deletions

diff --git a/configure.ac b/configure.ac
index 64046759f..3126cfcb0 100644
--- a/configure.ac
+++ b/configure.ac
@@ -1,4 +1,4 @@
-# $Id: configure.ac,v 1.317 2005/12/31 05:33:37 djm Exp $
+# $Id: configure.ac,v 1.318 2005/12/31 05:42:03 djm Exp $
 #
 # Copyright (c) 1999-2004 Damien Miller
 #
@@ -326,9 +326,16 @@ main() { if (NSVersionOfRunTimeLibrary("System") >= (60 << 16))
                         [Define if cmsg_type is not passed correctly])
                 ;;
         esac
-        AC_DEFINE(SSH_TUN_LINUX, 1, [Open tunnel devices the Linux tun/tap way])
-        AC_DEFINE(SSH_TUN_COMPAT_AF, 1, [Use tunnel device compatibility to OpenBSD])
-        AC_DEFINE(SSH_TUN_PREPEND_AF, 1, [Prepend the address family to IP tunnel traffic])
+        # tun(4) forwarding compat code
+        AC_CHECK_HEADERS(linux/tun.h)
+        if test "x$ac_cv_header_linux_tun_h" = "xyes" ; then
+                AC_DEFINE(SSH_TUN_LINUX, 1,
+                    [Open tunnel devices the Linux tun/tap way])
+                AC_DEFINE(SSH_TUN_COMPAT_AF, 1,
+                    [Use tunnel device compatibility to OpenBSD])
+                AC_DEFINE(SSH_TUN_PREPEND_AF, 1,
+                    [Prepend the address family to IP tunnel traffic])
+        fi
         ;;
 mips-sony-bsd|mips-sony-newsos4)
         AC_DEFINE(NEED_SETPRGP, 1, [Need setpgrp to acquire controlling tty])