ip/iplink_vxlan.c

/*
 * iplink_vxlan.c	VXLAN device support
 *
 *              This program is free software; you can redistribute it and/or
 *              modify it under the terms of the GNU General Public License
 *              as published by the Free Software Foundation; either version
 *              2 of the License, or (at your option) any later version.
 *
 * Authors:     Stephen Hemminger <shemminger@vyatta.com
 */

#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <net/if.h>
#include <linux/ip.h>
#include <linux/if_link.h>
#include <arpa/inet.h>

#include "rt_names.h"
#include "utils.h"
#include "ip_common.h"

#define VXLAN_ATTRSET(attrs, type) (((attrs) & (1L << (type))) != 0)

static void print_explain(FILE *f)
{
	fprintf(f,
		"Usage: ... vxlan id VNI\n"
		"                 [ { group | remote } IP_ADDRESS ]\n"
		"                 [ local ADDR ]\n"
		"                 [ ttl TTL ]\n"
		"                 [ tos TOS ]\n"
		"                 [ flowlabel LABEL ]\n"
		"                 [ dev PHYS_DEV ]\n"
		"                 [ dstport PORT ]\n"
		"                 [ srcport MIN MAX ]\n"
		"                 [ [no]learning ]\n"
		"                 [ [no]proxy ]\n"
		"                 [ [no]rsc ]\n"
		"                 [ [no]l2miss ]\n"
		"                 [ [no]l3miss ]\n"
		"                 [ ageing SECONDS ]\n"
		"                 [ maxaddress NUMBER ]\n"
		"                 [ [no]udpcsum ]\n"
		"                 [ [no]udp6zerocsumtx ]\n"
		"                 [ [no]udp6zerocsumrx ]\n"
		"                 [ [no]remcsumtx ] [ [no]remcsumrx ]\n"
		"                 [ [no]external ] [ gbp ] [ gpe ]\n"
		"\n"
		"Where: VNI   := 0-16777215\n"
		"       ADDR  := { IP_ADDRESS | any }\n"
		"       TOS   := { NUMBER | inherit }\n"
		"       TTL   := { 1..255 | inherit }\n"
		"       LABEL := 0-1048575\n"
	);
}

static void explain(void)
{
	print_explain(stderr);
}

static void check_duparg(__u64 *attrs, int type, const char *key,
			 const char *argv)
{
	if (!VXLAN_ATTRSET(*attrs, type)) {
		*attrs |= (1L << type);
		return;
	}
	duparg2(key, argv);
}

static int vxlan_parse_opt(struct link_util *lu, int argc, char **argv,
			  struct nlmsghdr *n)
{
	__u32 vni = 0;
	__u32 gaddr = 0;
	__u32 daddr = 0;
	struct in6_addr gaddr6 = IN6ADDR_ANY_INIT;
	struct in6_addr daddr6 = IN6ADDR_ANY_INIT;
	__u8 learning = 1;
	__u16 dstport = 0;
	__u8 metadata = 0;
	__u64 attrs = 0;
	bool set_op = (n->nlmsg_type == RTM_NEWLINK &&
		       !(n->nlmsg_flags & NLM_F_CREATE));

	while (argc > 0) {
		if (!matches(*argv, "id") ||
		    !matches(*argv, "vni")) {
			/* We will add ID attribute outside of the loop since we
			 * need to consider metadata information as well.
			 */
			NEXT_ARG();
			check_duparg(&attrs, IFLA_VXLAN_ID, "id", *argv);
			if (get_u32(&vni, *argv, 0) ||
			    vni >= 1u << 24)
				invarg("invalid id", *argv);
		} else if (!matches(*argv, "group")) {
			if (daddr || !IN6_IS_ADDR_UNSPECIFIED(&daddr6)) {
				fprintf(stderr, "vxlan: both group and remote");
				fprintf(stderr, " cannot be specified\n");
				return -1;
			}
			NEXT_ARG();
			check_duparg(&attrs, IFLA_VXLAN_GROUP, "group", *argv);
			if (!inet_get_addr(*argv, &gaddr, &gaddr6)) {
				fprintf(stderr, "Invalid address \"%s\"\n", *argv);
				return -1;
			}
			if (!IN6_IS_ADDR_MULTICAST(&gaddr6) && !IN_MULTICAST(ntohl(gaddr)))
				invarg("invalid group address", *argv);
		} else if (!matches(*argv, "remote")) {
			if (gaddr || !IN6_IS_ADDR_UNSPECIFIED(&gaddr6)) {
				fprintf(stderr, "vxlan: both group and remote");
				fprintf(stderr, " cannot be specified\n");
				return -1;
			}
			NEXT_ARG();
			check_duparg(&attrs, IFLA_VXLAN_GROUP, "remote", *argv);
			if (!inet_get_addr(*argv, &daddr, &daddr6)) {
				fprintf(stderr, "Invalid address \"%s\"\n", *argv);
				return -1;
			}
			if (IN6_IS_ADDR_MULTICAST(&daddr6) || IN_MULTICAST(ntohl(daddr)))
				invarg("invalid remote address", *argv);
		} else if (!matches(*argv, "local")) {
			__u32 saddr = 0;
			struct in6_addr saddr6 = IN6ADDR_ANY_INIT;

			NEXT_ARG();
			check_duparg(&attrs, IFLA_VXLAN_LOCAL, "local", *argv);
			if (strcmp(*argv, "any")) {
				if (!inet_get_addr(*argv, &saddr, &saddr6)) {
					fprintf(stderr, "Invalid address \"%s\"\n", *argv);
					return -1;
				}
			}

			if (IN_MULTICAST(ntohl(saddr)) || IN6_IS_ADDR_MULTICAST(&saddr6))
				invarg("invalid local address", *argv);

			if (saddr)
				addattr_l(n, 1024, IFLA_VXLAN_LOCAL, &saddr, 4);
			else if (!IN6_IS_ADDR_UNSPECIFIED(&saddr6))
				addattr_l(n, 1024, IFLA_VXLAN_LOCAL6, &saddr6,
					  sizeof(struct in6_addr));
		} else if (!matches(*argv, "dev")) {
			unsigned int link;

			NEXT_ARG();
			check_duparg(&attrs, IFLA_VXLAN_LINK, "dev", *argv);
			link = if_nametoindex(*argv);
			if (link == 0) {
				fprintf(stderr, "Cannot find device \"%s\"\n",
					*argv);
				exit(-1);
			}
			addattr32(n, 1024, IFLA_VXLAN_LINK, link);
		} else if (!matches(*argv, "ttl") ||
			   !matches(*argv, "hoplimit")) {
			unsigned int uval;
			__u8 ttl = 0;

			NEXT_ARG();
			check_duparg(&attrs, IFLA_VXLAN_TTL, "ttl", *argv);
			if (strcmp(*argv, "inherit") != 0) {
				if (get_unsigned(&uval, *argv, 0))
					invarg("invalid TTL", *argv);
				if (uval > 255)
					invarg("TTL must be <= 255", *argv);
				ttl = uval;
			}
			addattr8(n, 1024, IFLA_VXLAN_TTL, ttl);
		} else if (!matches(*argv, "tos") ||
			   !matches(*argv, "dsfield")) {
			__u32 uval;
			__u8 tos;

			NEXT_ARG();
			check_duparg(&attrs, IFLA_VXLAN_TOS, "tos", *argv);
			if (strcmp(*argv, "inherit") != 0) {
				if (rtnl_dsfield_a2n(&uval, *argv))
					invarg("bad TOS value", *argv);
				tos = uval;
			} else
				tos = 1;
			addattr8(n, 1024, IFLA_VXLAN_TOS, tos);
		} else if (!matches(*argv, "label") ||
			   !matches(*argv, "flowlabel")) {
			__u32 uval;

			NEXT_ARG();
			check_duparg(&attrs, IFLA_VXLAN_LABEL, "flowlabel",
				     *argv);
			if (get_u32(&uval, *argv, 0) ||
			    (uval & ~LABEL_MAX_MASK))
				invarg("invalid flowlabel", *argv);
			addattr32(n, 1024, IFLA_VXLAN_LABEL, htonl(uval));
		} else if (!matches(*argv, "ageing")) {
			__u32 age;

			NEXT_ARG();
			check_duparg(&attrs, IFLA_VXLAN_AGEING, "ageing",
				     *argv);
			if (strcmp(*argv, "none") == 0)
				age = 0;
			else if (get_u32(&age, *argv, 0))
				invarg("ageing timer", *argv);
			addattr32(n, 1024, IFLA_VXLAN_AGEING, age);
		} else if (!matches(*argv, "maxaddress")) {
			__u32 maxaddr;

			NEXT_ARG();
			check_duparg(&attrs, IFLA_VXLAN_LIMIT,
				     "maxaddress", *argv);
			if (strcmp(*argv, "unlimited") == 0)
				maxaddr = 0;
			else if (get_u32(&maxaddr, *argv, 0))
				invarg("max addresses", *argv);
			addattr32(n, 1024, IFLA_VXLAN_LIMIT, maxaddr);
		} else if (!matches(*argv, "port") ||
			   !matches(*argv, "srcport")) {
			struct ifla_vxlan_port_range range = { 0, 0 };

			NEXT_ARG();
			check_duparg(&attrs, IFLA_VXLAN_PORT_RANGE, "srcport",
				     *argv);
			if (get_be16(&range.low, *argv, 0))
				invarg("min port", *argv);
			NEXT_ARG();
			if (get_be16(&range.high, *argv, 0))
				invarg("max port", *argv);
			if (range.low || range.high) {
				addattr_l(n, 1024, IFLA_VXLAN_PORT_RANGE,
					  &range, sizeof(range));
			}
		} else if (!matches(*argv, "dstport")) {
			NEXT_ARG();
			check_duparg(&attrs, IFLA_VXLAN_PORT, "dstport", *argv);
			if (get_u16(&dstport, *argv, 0))
				invarg("dst port", *argv);
		} else if (!matches(*argv, "nolearning")) {
			check_duparg(&attrs, IFLA_VXLAN_LEARNING, *argv, *argv);
			learning = 0;
		} else if (!matches(*argv, "learning")) {
			check_duparg(&attrs, IFLA_VXLAN_LEARNING, *argv, *argv);
			learning = 1;
		} else if (!matches(*argv, "noproxy")) {
			check_duparg(&attrs, IFLA_VXLAN_PROXY, *argv, *argv);
			addattr8(n, 1024, IFLA_VXLAN_PROXY, 0);
		} else if (!matches(*argv, "proxy")) {
			check_duparg(&attrs, IFLA_VXLAN_PROXY, *argv, *argv);
			addattr8(n, 1024, IFLA_VXLAN_PROXY, 1);
		} else if (!matches(*argv, "norsc")) {
			check_duparg(&attrs, IFLA_VXLAN_RSC, *argv, *argv);
			addattr8(n, 1024, IFLA_VXLAN_RSC, 0);
		} else if (!matches(*argv, "rsc")) {
			check_duparg(&attrs, IFLA_VXLAN_RSC, *argv, *argv);
			addattr8(n, 1024, IFLA_VXLAN_RSC, 1);
		} else if (!matches(*argv, "nol2miss")) {
			check_duparg(&attrs, IFLA_VXLAN_L2MISS, *argv, *argv);
			addattr8(n, 1024, IFLA_VXLAN_L2MISS, 0);
		} else if (!matches(*argv, "l2miss")) {
			check_duparg(&attrs, IFLA_VXLAN_L2MISS, *argv, *argv);
			addattr8(n, 1024, IFLA_VXLAN_L2MISS, 1);
		} else if (!matches(*argv, "nol3miss")) {
			check_duparg(&attrs, IFLA_VXLAN_L3MISS, *argv, *argv);
			addattr8(n, 1024, IFLA_VXLAN_L3MISS, 0);
		} else if (!matches(*argv, "l3miss")) {
			check_duparg(&attrs, IFLA_VXLAN_L3MISS, *argv, *argv);
			addattr8(n, 1024, IFLA_VXLAN_L3MISS, 1);
		} else if (!matches(*argv, "udpcsum")) {
			check_duparg(&attrs, IFLA_VXLAN_UDP_CSUM, *argv, *argv);
			addattr8(n, 1024, IFLA_VXLAN_UDP_CSUM, 1);
		} else if (!matches(*argv, "noudpcsum")) {
			check_duparg(&attrs, IFLA_VXLAN_UDP_CSUM, *argv, *argv);
			addattr8(n, 1024, IFLA_VXLAN_UDP_CSUM, 0);
		} else if (!matches(*argv, "udp6zerocsumtx")) {
			check_duparg(&attrs, IFLA_VXLAN_UDP_ZERO_CSUM6_TX,
				     *argv, *argv);
			addattr8(n, 1024, IFLA_VXLAN_UDP_ZERO_CSUM6_TX, 1);
		} else if (!matches(*argv, "noudp6zerocsumtx")) {
			check_duparg(&attrs, IFLA_VXLAN_UDP_ZERO_CSUM6_TX,
				     *argv, *argv);
			addattr8(n, 1024, IFLA_VXLAN_UDP_ZERO_CSUM6_TX, 0);
		} else if (!matches(*argv, "udp6zerocsumrx")) {
			check_duparg(&attrs, IFLA_VXLAN_UDP_ZERO_CSUM6_RX,
				     *argv, *argv);
			addattr8(n, 1024, IFLA_VXLAN_UDP_ZERO_CSUM6_RX, 1);
		} else if (!matches(*argv, "noudp6zerocsumrx")) {
			check_duparg(&attrs, IFLA_VXLAN_UDP_ZERO_CSUM6_RX,
				     *argv, *argv);
			addattr8(n, 1024, IFLA_VXLAN_UDP_ZERO_CSUM6_RX, 0);
		} else if (!matches(*argv, "remcsumtx")) {
			check_duparg(&attrs, IFLA_VXLAN_REMCSUM_TX,
				     *argv, *argv);
			addattr8(n, 1024, IFLA_VXLAN_REMCSUM_TX, 1);
		} else if (!matches(*argv, "noremcsumtx")) {
			check_duparg(&attrs, IFLA_VXLAN_REMCSUM_TX,
				     *argv, *argv);
			addattr8(n, 1024, IFLA_VXLAN_REMCSUM_TX, 0);
		} else if (!matches(*argv, "remcsumrx")) {
			check_duparg(&attrs, IFLA_VXLAN_REMCSUM_RX,
				     *argv, *argv);
			addattr8(n, 1024, IFLA_VXLAN_REMCSUM_RX, 1);
		} else if (!matches(*argv, "noremcsumrx")) {
			check_duparg(&attrs, IFLA_VXLAN_REMCSUM_RX,
				     *argv, *argv);
			addattr8(n, 1024, IFLA_VXLAN_REMCSUM_RX, 0);
		} else if (!matches(*argv, "external")) {
			check_duparg(&attrs, IFLA_VXLAN_COLLECT_METADATA,
				     *argv, *argv);
			metadata = 1;
			learning = 0;
			/* we will add LEARNING attribute outside of the loop */
			addattr8(n, 1024, IFLA_VXLAN_COLLECT_METADATA,
				 metadata);
		} else if (!matches(*argv, "noexternal")) {
			check_duparg(&attrs, IFLA_VXLAN_COLLECT_METADATA,
				     *argv, *argv);
			metadata = 0;
			addattr8(n, 1024, IFLA_VXLAN_COLLECT_METADATA,
				 metadata);
		} else if (!matches(*argv, "gbp")) {
			check_duparg(&attrs, IFLA_VXLAN_GBP, *argv, *argv);
			addattr_l(n, 1024, IFLA_VXLAN_GBP, NULL, 0);
		} else if (!matches(*argv, "gpe")) {
			check_duparg(&attrs, IFLA_VXLAN_GPE, *argv, *argv);
			addattr_l(n, 1024, IFLA_VXLAN_GPE, NULL, 0);
		} else if (matches(*argv, "help") == 0) {
			explain();
			return -1;
		} else {
			fprintf(stderr, "vxlan: unknown command \"%s\"?\n", *argv);
			explain();
			return -1;
		}
		argc--, argv++;
	}

	if (metadata && VXLAN_ATTRSET(attrs, IFLA_VXLAN_ID)) {
		fprintf(stderr, "vxlan: both 'external' and vni cannot be specified\n");
		return -1;
	}

	if (!metadata && !VXLAN_ATTRSET(attrs, IFLA_VXLAN_ID)) {
		fprintf(stderr, "vxlan: missing virtual network identifier\n");
		return -1;
	}

	if ((gaddr || !IN6_IS_ADDR_UNSPECIFIED(&gaddr6)) &&
	    !VXLAN_ATTRSET(attrs, IFLA_VXLAN_LINK)) {
		fprintf(stderr, "vxlan: 'group' requires 'dev' to be specified\n");
		return -1;
	}

	if (!VXLAN_ATTRSET(attrs, IFLA_VXLAN_PORT) &&
	    VXLAN_ATTRSET(attrs, IFLA_VXLAN_GPE)) {
		dstport = 4790;
	} else if (!VXLAN_ATTRSET(attrs, IFLA_VXLAN_PORT) && !set_op) {
		fprintf(stderr, "vxlan: destination port not specified\n"
			"Will use Linux kernel default (non-standard value)\n");
		fprintf(stderr,
			"Use 'dstport 4789' to get the IANA assigned value\n"
			"Use 'dstport 0' to get default and quiet this message\n");
	}

	addattr32(n, 1024, IFLA_VXLAN_ID, vni);
	if (gaddr)
		addattr_l(n, 1024, IFLA_VXLAN_GROUP, &gaddr, 4);
	else if (daddr)
		addattr_l(n, 1024, IFLA_VXLAN_GROUP, &daddr, 4);
	else if (!IN6_IS_ADDR_UNSPECIFIED(&gaddr6))
		addattr_l(n, 1024, IFLA_VXLAN_GROUP6, &gaddr6, sizeof(struct in6_addr));
	else if (!IN6_IS_ADDR_UNSPECIFIED(&daddr6))
		addattr_l(n, 1024, IFLA_VXLAN_GROUP6, &daddr6, sizeof(struct in6_addr));
	else if (preferred_family == AF_INET)
		addattr_l(n, 1024, IFLA_VXLAN_GROUP, &daddr, 4);
	else if (preferred_family == AF_INET6)
		addattr_l(n, 1024, IFLA_VXLAN_GROUP6, &daddr6, sizeof(struct in6_addr));

	if (!set_op || VXLAN_ATTRSET(attrs, IFLA_VXLAN_LEARNING))
		addattr8(n, 1024, IFLA_VXLAN_LEARNING, learning);

	if (dstport)
		addattr16(n, 1024, IFLA_VXLAN_PORT, htons(dstport));

	return 0;
}

static void vxlan_print_opt(struct link_util *lu, FILE *f, struct rtattr *tb[])
{
	__u32 vni;
	unsigned int link;
	__u8 tos;
	__u32 maxaddr;
	char s2[64];

	if (!tb)
		return;

	if (!tb[IFLA_VXLAN_ID] ||
	    RTA_PAYLOAD(tb[IFLA_VXLAN_ID]) < sizeof(__u32))
		return;

	vni = rta_getattr_u32(tb[IFLA_VXLAN_ID]);
	fprintf(f, "id %u ", vni);

	if (tb[IFLA_VXLAN_GROUP]) {
		__be32 addr = rta_getattr_u32(tb[IFLA_VXLAN_GROUP]);

		if (addr) {
			if (IN_MULTICAST(ntohl(addr)))
				fprintf(f, "group %s ",
					format_host(AF_INET, 4, &addr));
			else
				fprintf(f, "remote %s ",
					format_host(AF_INET, 4, &addr));
		}
	} else if (tb[IFLA_VXLAN_GROUP6]) {
		struct in6_addr addr;

		memcpy(&addr, RTA_DATA(tb[IFLA_VXLAN_GROUP6]), sizeof(struct in6_addr));
		if (!IN6_IS_ADDR_UNSPECIFIED(&addr)) {
			if (IN6_IS_ADDR_MULTICAST(&addr))
				fprintf(f, "group %s ",
					format_host(AF_INET6, sizeof(struct in6_addr), &addr));
			else
				fprintf(f, "remote %s ",
					format_host(AF_INET6, sizeof(struct in6_addr), &addr));
		}
	}

	if (tb[IFLA_VXLAN_LOCAL]) {
		__be32 addr = rta_getattr_u32(tb[IFLA_VXLAN_LOCAL]);

		if (addr)
			fprintf(f, "local %s ",
				format_host(AF_INET, 4, &addr));
	} else if (tb[IFLA_VXLAN_LOCAL6]) {
		struct in6_addr addr;

		memcpy(&addr, RTA_DATA(tb[IFLA_VXLAN_LOCAL6]), sizeof(struct in6_addr));
		if (!IN6_IS_ADDR_UNSPECIFIED(&addr))
			fprintf(f, "local %s ",
				format_host(AF_INET6, sizeof(struct in6_addr), &addr));
	}

	if (tb[IFLA_VXLAN_LINK] &&
	    (link = rta_getattr_u32(tb[IFLA_VXLAN_LINK]))) {
		const char *n = if_indextoname(link, s2);

		if (n)
			fprintf(f, "dev %s ", n);
		else
			fprintf(f, "dev %u ", link);
	}

	if (tb[IFLA_VXLAN_PORT_RANGE]) {
		const struct ifla_vxlan_port_range *r
			= RTA_DATA(tb[IFLA_VXLAN_PORT_RANGE]);
		fprintf(f, "srcport %u %u ", ntohs(r->low), ntohs(r->high));
	}

	if (tb[IFLA_VXLAN_PORT])
		fprintf(f, "dstport %u ",
			rta_getattr_be16(tb[IFLA_VXLAN_PORT]));

	if (tb[IFLA_VXLAN_LEARNING] &&
	    !rta_getattr_u8(tb[IFLA_VXLAN_LEARNING]))
		fputs("nolearning ", f);

	if (tb[IFLA_VXLAN_PROXY] && rta_getattr_u8(tb[IFLA_VXLAN_PROXY]))
		fputs("proxy ", f);

	if (tb[IFLA_VXLAN_RSC] && rta_getattr_u8(tb[IFLA_VXLAN_RSC]))
		fputs("rsc ", f);

	if (tb[IFLA_VXLAN_L2MISS] && rta_getattr_u8(tb[IFLA_VXLAN_L2MISS]))
		fputs("l2miss ", f);

	if (tb[IFLA_VXLAN_L3MISS] && rta_getattr_u8(tb[IFLA_VXLAN_L3MISS]))
		fputs("l3miss ", f);

	if (tb[IFLA_VXLAN_TOS] &&
	    (tos = rta_getattr_u8(tb[IFLA_VXLAN_TOS]))) {
		if (tos == 1)
			fprintf(f, "tos inherit ");
		else
			fprintf(f, "tos %#x ", tos);
	}

	if (tb[IFLA_VXLAN_TTL]) {
		__u8 ttl = rta_getattr_u8(tb[IFLA_VXLAN_TTL]);

		if (ttl)
			fprintf(f, "ttl %d ", ttl);
	}

	if (tb[IFLA_VXLAN_LABEL]) {
		__u32 label = rta_getattr_u32(tb[IFLA_VXLAN_LABEL]);

		if (label)
			fprintf(f, "flowlabel %#x ", ntohl(label));
	}

	if (tb[IFLA_VXLAN_AGEING]) {
		__u32 age = rta_getattr_u32(tb[IFLA_VXLAN_AGEING]);

		if (age == 0)
			fprintf(f, "ageing none ");
		else
			fprintf(f, "ageing %u ", age);
	}

	if (tb[IFLA_VXLAN_LIMIT] &&
	    ((maxaddr = rta_getattr_u32(tb[IFLA_VXLAN_LIMIT])) != 0))
		    fprintf(f, "maxaddr %u ", maxaddr);

	if (tb[IFLA_VXLAN_UDP_CSUM]) {
		if (!rta_getattr_u8(tb[IFLA_VXLAN_UDP_CSUM]))
			fputs("no", f);
		fputs("udpcsum ", f);
	}

	if (tb[IFLA_VXLAN_UDP_ZERO_CSUM6_TX]) {
		if (!rta_getattr_u8(tb[IFLA_VXLAN_UDP_ZERO_CSUM6_TX]))
			fputs("no", f);
		fputs("udp6zerocsumtx ", f);
	}

	if (tb[IFLA_VXLAN_UDP_ZERO_CSUM6_RX]) {
		if (!rta_getattr_u8(tb[IFLA_VXLAN_UDP_ZERO_CSUM6_RX]))
			fputs("no", f);
		fputs("udp6zerocsumrx ", f);
	}

	if (tb[IFLA_VXLAN_REMCSUM_TX] &&
	    rta_getattr_u8(tb[IFLA_VXLAN_REMCSUM_TX]))
		fputs("remcsumtx ", f);

	if (tb[IFLA_VXLAN_REMCSUM_RX] &&
	    rta_getattr_u8(tb[IFLA_VXLAN_REMCSUM_RX]))
		fputs("remcsumrx ", f);

	if (tb[IFLA_VXLAN_COLLECT_METADATA] &&
	    rta_getattr_u8(tb[IFLA_VXLAN_COLLECT_METADATA]))
		fputs("external ", f);

	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,
	FILE *f)
{
	print_explain(f);
}

struct link_util vxlan_link_util = {
	.id		= "vxlan",
	.maxattr	= IFLA_VXLAN_MAX,
	.parse_opt	= vxlan_parse_opt,
	.print_opt	= vxlan_print_opt,
	.print_help	= vxlan_print_help,
};