+static int
+ipt_mac_checkentry(const char *tablename,
+ const void *inf,
+ void *matchinfo,
+ unsigned int matchsize,
+ unsigned int hook_mask)
+{
+ /* FORWARD isn't always valid, but it's nice to be able to do --RR */
+ if (hook_mask
+ & ~((1 << NF_IP_PRE_ROUTING) | (1 << NF_IP_LOCAL_IN)
+ | (1 << NF_IP_FORWARD))) {
+ printk("xt_mac: only valid for PRE_ROUTING, LOCAL_IN or FORWARD.\n");
+ return 0;
+ }
+
+ if (matchsize != XT_ALIGN(sizeof(struct xt_mac_info)))
+ return 0;
+
+ return 1;
+}
+