build: add support for Linux 4.18

.gitignore

@@ -3,6 +3,7 @@
 *.lo
 *.loT
 *.o
+.cache.mk
 .deps/
 .dirstamp
 .libs/

configure.ac

@@ -57,9 +57,9 @@ if test -n "$kbuilddir"; then
 		echo "WARNING: Version detection did not succeed. Continue at own luck.";
 	else
 		echo "$kmajor.$kminor.$kmicro.$kstable in $kbuilddir";
-		if test "$kmajor" -gt 4 -o "$kmajor" -eq 4 -a "$kminor" -gt 17; then
+		if test "$kmajor" -gt 4 -o "$kmajor" -eq 4 -a "$kminor" -gt 18; then
 			echo "WARNING: That kernel version is not officially supported yet. Continue at own luck.";
-		elif test "$kmajor" -eq 4 -a "$kminor" -ge 17; then
+		elif test "$kmajor" -eq 4 -a "$kminor" -ge 18; then
 			:
 		else
 			echo "WARNING: That kernel version is not officially supported.";

doc/changelog.txt

@@ -2,7 +2,7 @@
 HEAD
 ====
 Enhancements:
-- support for Linux 4.17
+- support for Linux 4.17, 4.18
 
 
 v3.0 (2018-02-12)

extensions/xt_DNETMAP.c

@@ -363,7 +363,11 @@ dnetmap_tg(struct sk_buff *skb, const struct xt_action_param *par)
 	__be32 prenat_ip, postnat_ip, prenat_ip_prev;
 	const struct xt_DNETMAP_tginfo *tginfo = par->targinfo;
 	const struct nf_nat_range *mr = &tginfo->prefix;
+#if LINUX_VERSION_CODE >= KERNEL_VERSION(4, 18, 0)
+	struct nf_nat_range2 newrange;
+#else
 	struct nf_nat_range newrange;
+#endif
 	struct dnetmap_entry *e;
 	struct dnetmap_prefix *p;
 	__s32 jttl;