vxlan: add support for VXLAN-GPE

Adds support to create a VXLAN-GPE interface.
Signed-off-by: Jiri Benc <jbenc@redhat.com>

ip/iplink_vxlan.c

@@ -31,7 +31,7 @@ static void print_explain(FILE *f)
 	fprintf(f, "                 [ ageing SECONDS ] [ maxaddress NUMBER ]\n");
 	fprintf(f, "                 [ [no]udpcsum ] [ [no]udp6zerocsumtx ] [ [no]udp6zerocsumrx ]\n");
 	fprintf(f, "                 [ [no]remcsumtx ] [ [no]remcsumrx ]\n");
-	fprintf(f, "                 [ [no]external ] [ gbp ]\n");
+	fprintf(f, "                 [ [no]external ] [ gbp ] [ gpe ]\n");
 	fprintf(f, "\n");
 	fprintf(f, "Where: VNI   := 0-16777215\n");
 	fprintf(f, "       ADDR  := { IP_ADDRESS | any }\n");
@@ -79,6 +79,7 @@ static int vxlan_parse_opt(struct link_util *lu, int argc, char **argv,
 	__u8 remcsumrx = 0;
 	__u8 metadata = 0;
 	__u8 gbp = 0;
+	__u8 gpe = 0;
 	int dst_port_set = 0;
 	struct ifla_vxlan_port_range range = { 0, 0 };
 
@@ -239,6 +240,8 @@ static int vxlan_parse_opt(struct link_util *lu, int argc, char **argv,
 			metadata = 0;
 		} else if (!matches(*argv, "gbp")) {
 			gbp = 1;
+		} else if (!matches(*argv, "gpe")) {
+			gpe = 1;
 		} else if (matches(*argv, "help") == 0) {
 			explain();
 			return -1;
@@ -267,7 +270,9 @@ static int vxlan_parse_opt(struct link_util *lu, int argc, char **argv,
 		return -1;
 	}
 
-	if (!dst_port_set) {
+	if (!dst_port_set && gpe) {
+		dstport = 4790;
+	} else if (!dst_port_set) {
 		fprintf(stderr, "vxlan: destination port not specified\n"
 			"Will use Linux kernel default (non-standard value)\n");
 		fprintf(stderr,
@@ -324,6 +329,8 @@ static int vxlan_parse_opt(struct link_util *lu, int argc, char **argv,
 
 	if (gbp)
 		addattr_l(n, 1024, IFLA_VXLAN_GBP, NULL, 0);
+	if (gpe)
+		addattr_l(n, 1024, IFLA_VXLAN_GPE, NULL, 0);
 
 
 	return 0;
@@ -490,6 +497,8 @@ static void vxlan_print_opt(struct link_util *lu, FILE *f, struct rtattr *tb[])
 
 	if (tb[IFLA_VXLAN_GBP])
 		fputs("gbp ", f);
+	if (tb[IFLA_VXLAN_GPE])
+		fputs("gpe ", f);
 }
 
 static void vxlan_print_help(struct link_util *lu, int argc, char **argv,

man/man8/ip-link.8.in

@@ -425,6 +425,8 @@ the following additional arguments are supported:
 .RI "[no]external "
 ] [
 .B gbp
+] [
+.B gpe
 ]
 
 .in +8
@@ -566,6 +568,13 @@ Example:
 
 .in -4
 
+.sp
+.B gpe
+- enables the Generic Protocol extension (VXLAN-GPE). Currently, this is
+only supported together with the
+.B external
+keyword.
+
 .in -8
 
 .TP