netfilter: nf_tables: add tunnel support

This patch implements the tunnel object type that can be used to
configure tunnels via metadata template through the existing lightweight
API from the ingress path.

Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>

5 files changed, 534 insertions, 1 deletions

diff --git a/include/uapi/linux/netfilter/nf_tables.h b/include/uapi/linux/netfilter/nf_tables.h
index f112ea52dc1a..3ee1198eeac1 100644
--- a/include/uapi/linux/netfilter/nf_tables.h
+++ b/include/uapi/linux/netfilter/nf_tables.h
@@ -1416,7 +1416,8 @@ enum nft_ct_helper_attributes {
 #define NFT_OBJECT_CT_HELPER    3
 #define NFT_OBJECT_LIMIT        4
 #define NFT_OBJECT_CONNLIMIT    5
-#define __NFT_OBJECT_MAX        6
+#define NFT_OBJECT_TUNNEL       6
+#define __NFT_OBJECT_MAX        7
 #define NFT_OBJECT_MAX          (__NFT_OBJECT_MAX - 1)
 
 /**
@@ -1580,4 +1581,70 @@ enum nft_ng_types {
 };
 #define NFT_NG_MAX      (__NFT_NG_MAX - 1)
 
+enum nft_tunnel_key_ip_attributes {
+        NFTA_TUNNEL_KEY_IP_UNSPEC,
+        NFTA_TUNNEL_KEY_IP_SRC,
+        NFTA_TUNNEL_KEY_IP_DST,
+        __NFTA_TUNNEL_KEY_IP_MAX
+};
+#define NFTA_TUNNEL_KEY_IP_MAX  (__NFTA_TUNNEL_KEY_IP_MAX - 1)
+
+enum nft_tunnel_ip6_attributes {
+        NFTA_TUNNEL_KEY_IP6_UNSPEC,
+        NFTA_TUNNEL_KEY_IP6_SRC,
+        NFTA_TUNNEL_KEY_IP6_DST,
+        NFTA_TUNNEL_KEY_IP6_FLOWLABEL,
+        __NFTA_TUNNEL_KEY_IP6_MAX
+};
+#define NFTA_TUNNEL_KEY_IP6_MAX (__NFTA_TUNNEL_KEY_IP6_MAX - 1)
+
+enum nft_tunnel_opts_attributes {
+        NFTA_TUNNEL_KEY_OPTS_UNSPEC,
+        NFTA_TUNNEL_KEY_OPTS_VXLAN,
+        NFTA_TUNNEL_KEY_OPTS_ERSPAN,
+        __NFTA_TUNNEL_KEY_OPTS_MAX
+};
+#define NFTA_TUNNEL_KEY_OPTS_MAX        (__NFTA_TUNNEL_KEY_OPTS_MAX - 1)
+
+enum nft_tunnel_opts_vxlan_attributes {
+        NFTA_TUNNEL_KEY_VXLAN_UNSPEC,
+        NFTA_TUNNEL_KEY_VXLAN_GBP,
+        __NFTA_TUNNEL_KEY_VXLAN_MAX
+};
+#define NFTA_TUNNEL_KEY_VXLAN_MAX       (__NFTA_TUNNEL_KEY_VXLAN_MAX - 1)
+
+enum nft_tunnel_opts_erspan_attributes {
+        NFTA_TUNNEL_KEY_ERSPAN_UNSPEC,
+        NFTA_TUNNEL_KEY_ERSPAN_VERSION,
+        NFTA_TUNNEL_KEY_ERSPAN_V1_INDEX,
+        NFTA_TUNNEL_KEY_ERSPAN_V2_HWID,
+        NFTA_TUNNEL_KEY_ERSPAN_V2_DIR,
+        __NFTA_TUNNEL_KEY_ERSPAN_MAX
+};
+#define NFTA_TUNNEL_KEY_ERSPAN_MAX      (__NFTA_TUNNEL_KEY_ERSPAN_MAX - 1)
+
+enum nft_tunnel_flags {
+        NFT_TUNNEL_F_ZERO_CSUM_TX       = (1 << 0),
+        NFT_TUNNEL_F_DONT_FRAGMENT      = (1 << 1),
+        NFT_TUNNEL_F_SEQ_NUMBER         = (1 << 2),
+};
+#define NFT_TUNNEL_F_MASK       (NFT_TUNNEL_F_ZERO_CSUM_TX | \
+                                 NFT_TUNNEL_F_DONT_FRAGMENT | \
+                                 NFT_TUNNEL_F_SEQ_NUMBER)
+
+enum nft_tunnel_key_attributes {
+        NFTA_TUNNEL_KEY_UNSPEC,
+        NFTA_TUNNEL_KEY_ID,
+        NFTA_TUNNEL_KEY_IP,
+        NFTA_TUNNEL_KEY_IP6,
+        NFTA_TUNNEL_KEY_FLAGS,
+        NFTA_TUNNEL_KEY_TOS,
+        NFTA_TUNNEL_KEY_TTL,
+        NFTA_TUNNEL_KEY_SPORT,
+        NFTA_TUNNEL_KEY_DPORT,
+        NFTA_TUNNEL_KEY_OPTS,
+        __NFTA_TUNNEL_KEY_MAX
+};
+#define NFTA_TUNNEL_KEY_MAX     (__NFTA_TUNNEL_KEY_MAX - 1)
+
 #endif /* _LINUX_NF_TABLES_H */
diff --git a/net/core/dst.c b/net/core/dst.c
index 2d9b37f8944a..81ccf20e2826 100644
--- a/net/core/dst.c
+++ b/net/core/dst.c
@@ -307,6 +307,7 @@ void metadata_dst_free(struct metadata_dst *md_dst)
 #endif
         kfree(md_dst);
 }
+EXPORT_SYMBOL_GPL(metadata_dst_free);
 
 struct metadata_dst __percpu *
 metadata_dst_alloc_percpu(u8 optslen, enum metadata_type type, gfp_t flags)
diff --git a/net/netfilter/Kconfig b/net/netfilter/Kconfig
index 55e399d5af10..654588088676 100644
--- a/net/netfilter/Kconfig
+++ b/net/netfilter/Kconfig
@@ -559,6 +559,12 @@ config NFT_NAT
           This option adds the "nat" expression that you can use to perform
           typical Network Address Translation (NAT) packet transformations.
 
+config NFT_TUNNEL
+        tristate "Netfilter nf_tables tunnel module"
+        help
+          This option adds the "tunnel" expression that you can use to set
+          tunneling policies.
+
 config NFT_OBJREF
         tristate "Netfilter nf_tables stateful object reference module"
         help
diff --git a/net/netfilter/Makefile b/net/netfilter/Makefile
index cf61615cc529..16895e045b66 100644
--- a/net/netfilter/Makefile
+++ b/net/netfilter/Makefile
@@ -101,6 +101,7 @@ obj-$(CONFIG_NFT_QUEUE)		+= nft_queue.o
 obj-$(CONFIG_NFT_QUOTA)         += nft_quota.o
 obj-$(CONFIG_NFT_REJECT)        += nft_reject.o
 obj-$(CONFIG_NFT_REJECT_INET)   += nft_reject_inet.o
+obj-$(CONFIG_NFT_TUNNEL)        += nft_tunnel.o
 obj-$(CONFIG_NFT_COUNTER)       += nft_counter.o
 obj-$(CONFIG_NFT_LOG)           += nft_log.o
 obj-$(CONFIG_NFT_MASQ)          += nft_masq.o
diff --git a/net/netfilter/nft_tunnel.c b/net/netfilter/nft_tunnel.c
new file mode 100644
index 000000000000..715613d99c20
--- /dev/null
+++ b/net/netfilter/nft_tunnel.c
@@ -0,0 +1,458 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+#include <linux/kernel.h>
+#include <linux/init.h>
+#include <linux/module.h>
+#include <linux/seqlock.h>
+#include <linux/netlink.h>
+#include <linux/netfilter.h>
+#include <linux/netfilter/nf_tables.h>
+#include <net/netfilter/nf_tables.h>
+#include <net/dst_metadata.h>
+#include <net/ip_tunnels.h>
+#include <net/vxlan.h>
+#include <net/erspan.h>
+
+struct nft_tunnel_opts {
+        union {
+                struct vxlan_metadata   vxlan;
+                struct erspan_metadata  erspan;
+        } u;
+        u32     len;
+        u32     flags;
+};
+
+struct nft_tunnel_obj {
+        struct metadata_dst     *md;
+        struct nft_tunnel_opts  opts;
+};
+
+static const struct nla_policy nft_tunnel_ip_policy[NFTA_TUNNEL_KEY_IP_MAX + 1] = {
+        [NFTA_TUNNEL_KEY_IP_SRC]        = { .type = NLA_U32 },
+        [NFTA_TUNNEL_KEY_IP_DST]        = { .type = NLA_U32 },
+};
+
+static int nft_tunnel_obj_ip_init(const struct nft_ctx *ctx,
+                                  const struct nlattr *attr,
+                                  struct ip_tunnel_info *info)
+{
+        struct nlattr *tb[NFTA_TUNNEL_KEY_IP_MAX + 1];
+        int err;
+
+        err = nla_parse_nested(tb, NFTA_TUNNEL_KEY_IP_MAX, attr,
+                               nft_tunnel_ip_policy, NULL);
+        if (err < 0)
+                return err;
+
+        if (!tb[NFTA_TUNNEL_KEY_IP_DST])
+                return -EINVAL;
+
+        if (tb[NFTA_TUNNEL_KEY_IP_SRC])
+                info->key.u.ipv4.src = nla_get_be32(tb[NFTA_TUNNEL_KEY_IP_SRC]);
+        if (tb[NFTA_TUNNEL_KEY_IP_DST])
+                info->key.u.ipv4.dst = nla_get_be32(tb[NFTA_TUNNEL_KEY_IP_DST]);
+
+        return 0;
+}
+
+static const struct nla_policy nft_tunnel_ip6_policy[NFTA_TUNNEL_KEY_IP6_MAX + 1] = {
+        [NFTA_TUNNEL_KEY_IP6_SRC]       = { .len = sizeof(struct in6_addr), },
+        [NFTA_TUNNEL_KEY_IP6_DST]       = { .len = sizeof(struct in6_addr), },
+        [NFTA_TUNNEL_KEY_IP6_FLOWLABEL] = { .type = NLA_U32, }
+};
+
+static int nft_tunnel_obj_ip6_init(const struct nft_ctx *ctx,
+                                   const struct nlattr *attr,
+                                   struct ip_tunnel_info *info)
+{
+        struct nlattr *tb[NFTA_TUNNEL_KEY_IP6_MAX + 1];
+        int err;
+
+        err = nla_parse_nested(tb, NFTA_TUNNEL_KEY_IP6_MAX, attr,
+                               nft_tunnel_ip6_policy, NULL);
+        if (err < 0)
+                return err;
+
+        if (!tb[NFTA_TUNNEL_KEY_IP6_DST])
+                return -EINVAL;
+
+        if (tb[NFTA_TUNNEL_KEY_IP6_SRC]) {
+                memcpy(&info->key.u.ipv6.src,
+                       nla_data(tb[NFTA_TUNNEL_KEY_IP6_SRC]),
+                       sizeof(struct in6_addr));
+        }
+        if (tb[NFTA_TUNNEL_KEY_IP6_DST]) {
+                memcpy(&info->key.u.ipv6.dst,
+                       nla_data(tb[NFTA_TUNNEL_KEY_IP6_DST]),
+                       sizeof(struct in6_addr));
+        }
+        if (tb[NFTA_TUNNEL_KEY_IP6_FLOWLABEL])
+                info->key.label = nla_get_be32(tb[NFTA_TUNNEL_KEY_IP6_FLOWLABEL]);
+
+        info->mode |= IP_TUNNEL_INFO_IPV6;
+
+        return 0;
+}
+
+static const struct nla_policy nft_tunnel_opts_vxlan_policy[NFTA_TUNNEL_KEY_VXLAN_MAX + 1] = {
+        [NFTA_TUNNEL_KEY_VXLAN_GBP]     = { .type = NLA_U32 },
+};
+
+static int nft_tunnel_obj_vxlan_init(const struct nlattr *attr,
+                                     struct nft_tunnel_opts *opts)
+{
+        struct nlattr *tb[NFTA_TUNNEL_KEY_VXLAN_MAX + 1];
+        int err;
+
+        err = nla_parse_nested(tb, NFTA_TUNNEL_KEY_VXLAN_MAX, attr,
+                               nft_tunnel_opts_vxlan_policy, NULL);
+        if (err < 0)
+                return err;
+
+        if (!tb[NFTA_TUNNEL_KEY_VXLAN_GBP])
+                return -EINVAL;
+
+        opts->u.vxlan.gbp = ntohl(nla_get_be32(tb[NFTA_TUNNEL_KEY_VXLAN_GBP]));
+
+        opts->len       = sizeof(struct vxlan_metadata);
+        opts->flags     = TUNNEL_VXLAN_OPT;
+
+        return 0;
+}
+
+static const struct nla_policy nft_tunnel_opts_erspan_policy[NFTA_TUNNEL_KEY_ERSPAN_MAX + 1] = {
+        [NFTA_TUNNEL_KEY_ERSPAN_V1_INDEX]       = { .type = NLA_U32 },
+        [NFTA_TUNNEL_KEY_ERSPAN_V2_DIR] = { .type = NLA_U8 },
+        [NFTA_TUNNEL_KEY_ERSPAN_V2_HWID]        = { .type = NLA_U8 },
+};
+
+static int nft_tunnel_obj_erspan_init(const struct nlattr *attr,
+                                      struct nft_tunnel_opts *opts)
+{
+        struct nlattr *tb[NFTA_TUNNEL_KEY_ERSPAN_MAX + 1];
+        uint8_t hwid, dir;
+        int err, version;
+
+        err = nla_parse_nested(tb, NFTA_TUNNEL_KEY_ERSPAN_MAX, attr,
+                               nft_tunnel_opts_erspan_policy, NULL);
+        if (err < 0)
+                return err;
+
+        version = ntohl(nla_get_be32(tb[NFTA_TUNNEL_KEY_ERSPAN_VERSION]));
+        switch (version) {
+        case ERSPAN_VERSION:
+                if (!tb[NFTA_TUNNEL_KEY_ERSPAN_V1_INDEX])
+                        return -EINVAL;
+
+                opts->u.erspan.u.index =
+                        nla_get_be32(tb[NFTA_TUNNEL_KEY_ERSPAN_V1_INDEX]);
+                break;
+        case ERSPAN_VERSION2:
+                if (!tb[NFTA_TUNNEL_KEY_ERSPAN_V2_DIR] ||
+                    !tb[NFTA_TUNNEL_KEY_ERSPAN_V2_HWID])
+                        return -EINVAL;
+
+                hwid = nla_get_u8(tb[NFTA_TUNNEL_KEY_ERSPAN_V2_HWID]);
+                dir = nla_get_u8(tb[NFTA_TUNNEL_KEY_ERSPAN_V2_DIR]);
+
+                set_hwid(&opts->u.erspan.u.md2, hwid);
+                opts->u.erspan.u.md2.dir = dir;
+                break;
+        default:
+                return -EOPNOTSUPP;
+        }
+        opts->u.erspan.version = version;
+
+        opts->len       = sizeof(struct erspan_metadata);
+        opts->flags     = TUNNEL_ERSPAN_OPT;
+
+        return 0;
+}
+
+static const struct nla_policy nft_tunnel_opts_policy[NFTA_TUNNEL_KEY_OPTS_MAX + 1] = {
+        [NFTA_TUNNEL_KEY_OPTS_VXLAN]    = { .type = NLA_NESTED, },
+        [NFTA_TUNNEL_KEY_OPTS_ERSPAN]   = { .type = NLA_NESTED, },
+};
+
+static int nft_tunnel_obj_opts_init(const struct nft_ctx *ctx,
+                                    const struct nlattr *attr,
+                                    struct ip_tunnel_info *info,
+                                    struct nft_tunnel_opts *opts)
+{
+        struct nlattr *tb[NFTA_TUNNEL_KEY_OPTS_MAX + 1];
+        int err;
+
+        err = nla_parse_nested(tb, NFTA_TUNNEL_KEY_OPTS_MAX, attr,
+                               nft_tunnel_opts_policy, NULL);
+        if (err < 0)
+                return err;
+
+        if (tb[NFTA_TUNNEL_KEY_OPTS_VXLAN]) {
+                err = nft_tunnel_obj_vxlan_init(tb[NFTA_TUNNEL_KEY_OPTS_VXLAN],
+                                                opts);
+        } else if (tb[NFTA_TUNNEL_KEY_OPTS_ERSPAN]) {
+                err = nft_tunnel_obj_erspan_init(tb[NFTA_TUNNEL_KEY_OPTS_ERSPAN],
+                                                 opts);
+        } else {
+                return -EOPNOTSUPP;
+        }
+
+        return err;
+}
+
+static const struct nla_policy nft_tunnel_key_policy[NFTA_TUNNEL_KEY_MAX + 1] = {
+        [NFTA_TUNNEL_KEY_IP]    = { .type = NLA_NESTED, },
+        [NFTA_TUNNEL_KEY_IP6]   = { .type = NLA_NESTED, },
+        [NFTA_TUNNEL_KEY_ID]    = { .type = NLA_U32, },
+        [NFTA_TUNNEL_KEY_FLAGS] = { .type = NLA_U32, },
+        [NFTA_TUNNEL_KEY_TOS]   = { .type = NLA_U8, },
+        [NFTA_TUNNEL_KEY_TTL]   = { .type = NLA_U8, },
+        [NFTA_TUNNEL_KEY_OPTS]  = { .type = NLA_NESTED, },
+};
+
+static int nft_tunnel_obj_init(const struct nft_ctx *ctx,
+                               const struct nlattr * const tb[],
+                               struct nft_object *obj)
+{
+        struct nft_tunnel_obj *priv = nft_obj_data(obj);
+        struct ip_tunnel_info info;
+        struct metadata_dst *md;
+        int err;
+
+        if (!tb[NFTA_TUNNEL_KEY_ID])
+                return -EINVAL;
+
+        memset(&info, 0, sizeof(info));
+        info.mode               = IP_TUNNEL_INFO_TX;
+        info.key.tun_id         = key32_to_tunnel_id(nla_get_be32(tb[NFTA_TUNNEL_KEY_ID]));
+        info.key.tun_flags      = TUNNEL_KEY | TUNNEL_CSUM | TUNNEL_NOCACHE;
+
+        if (tb[NFTA_TUNNEL_KEY_IP]) {
+                err = nft_tunnel_obj_ip_init(ctx, tb[NFTA_TUNNEL_KEY_IP], &info);
+                if (err < 0)
+                        return err;
+        } else if (tb[NFTA_TUNNEL_KEY_IP6]) {
+                err = nft_tunnel_obj_ip6_init(ctx, tb[NFTA_TUNNEL_KEY_IP6], &info);
+                if (err < 0)
+                        return err;
+        } else {
+                return -EINVAL;
+        }
+
+        if (tb[NFTA_TUNNEL_KEY_SPORT]) {
+                info.key.tp_src =
+                        ntohs(nla_get_be16(tb[NFTA_TUNNEL_KEY_SPORT]));
+        }
+        if (tb[NFTA_TUNNEL_KEY_DPORT]) {
+                info.key.tp_dst =
+                        ntohs(nla_get_be16(tb[NFTA_TUNNEL_KEY_DPORT]));
+        }
+
+        if (tb[NFTA_TUNNEL_KEY_FLAGS]) {
+                u32 tun_flags;
+
+                tun_flags = ntohl(nla_get_be32(tb[NFTA_TUNNEL_KEY_FLAGS]));
+                if (tun_flags & ~NFT_TUNNEL_F_MASK)
+                        return -EOPNOTSUPP;
+
+                if (tun_flags & NFT_TUNNEL_F_ZERO_CSUM_TX)
+                        info.key.tun_flags &= ~TUNNEL_CSUM;
+                if (tun_flags & NFT_TUNNEL_F_DONT_FRAGMENT)
+                        info.key.tun_flags |= TUNNEL_DONT_FRAGMENT;
+                if (tun_flags & NFT_TUNNEL_F_SEQ_NUMBER)
+                        info.key.tun_flags |= TUNNEL_SEQ;
+        }
+        if (tb[NFTA_TUNNEL_KEY_TOS])
+                info.key.tos = nla_get_u8(tb[NFTA_TUNNEL_KEY_TOS]);
+        if (tb[NFTA_TUNNEL_KEY_TTL])
+                info.key.ttl = nla_get_u8(tb[NFTA_TUNNEL_KEY_TTL]);
+        else
+                info.key.ttl = U8_MAX;
+
+        if (tb[NFTA_TUNNEL_KEY_OPTS]) {
+                err = nft_tunnel_obj_opts_init(ctx, tb[NFTA_TUNNEL_KEY_OPTS],
+                                               &info, &priv->opts);
+                if (err < 0)
+                        return err;
+        }
+
+        md = metadata_dst_alloc(priv->opts.len, METADATA_IP_TUNNEL, GFP_KERNEL);
+        if (!md)
+                return -ENOMEM;
+
+        memcpy(&md->u.tun_info, &info, sizeof(info));
+        ip_tunnel_info_opts_set(&md->u.tun_info, &priv->opts.u, priv->opts.len,
+                                priv->opts.flags);
+        priv->md = md;
+
+        return 0;
+}
+
+static inline void nft_tunnel_obj_eval(struct nft_object *obj,
+                                       struct nft_regs *regs,
+                                       const struct nft_pktinfo *pkt)
+{
+        struct nft_tunnel_obj *priv = nft_obj_data(obj);
+        struct sk_buff *skb = pkt->skb;
+
+        skb_dst_drop(skb);
+        dst_hold((struct dst_entry *) priv->md);
+        skb_dst_set(skb, (struct dst_entry *) priv->md);
+}
+
+static int nft_tunnel_ip_dump(struct sk_buff *skb, struct ip_tunnel_info *info)
+{
+        struct nlattr *nest;
+
+        if (info->mode & IP_TUNNEL_INFO_IPV6) {
+                nest = nla_nest_start(skb, NFTA_TUNNEL_KEY_IP6);
+                if (!nest)
+                        return -1;
+
+                if (nla_put_in6_addr(skb, NFTA_TUNNEL_KEY_IP6_SRC, &info->key.u.ipv6.src) < 0 ||
+                    nla_put_in6_addr(skb, NFTA_TUNNEL_KEY_IP6_DST, &info->key.u.ipv6.dst) < 0 ||
+                    nla_put_be32(skb, NFTA_TUNNEL_KEY_IP6_FLOWLABEL, info->key.label))
+                        return -1;
+
+                nla_nest_end(skb, nest);
+        } else {
+                nest = nla_nest_start(skb, NFTA_TUNNEL_KEY_IP);
+                if (!nest)
+                        return -1;
+
+                if (nla_put_in_addr(skb, NFTA_TUNNEL_KEY_IP_SRC, info->key.u.ipv4.src) < 0 ||
+                    nla_put_in_addr(skb, NFTA_TUNNEL_KEY_IP_DST, info->key.u.ipv4.dst) < 0)
+                        return -1;
+
+                nla_nest_end(skb, nest);
+        }
+
+        return 0;
+}
+
+static int nft_tunnel_opts_dump(struct sk_buff *skb,
+                                struct nft_tunnel_obj *priv)
+{
+        struct nft_tunnel_opts *opts = &priv->opts;
+        struct nlattr *nest;
+
+        nest = nla_nest_start(skb, NFTA_TUNNEL_KEY_OPTS);
+        if (!nest)
+                return -1;
+
+        if (opts->flags & TUNNEL_VXLAN_OPT) {
+                if (nla_put_be32(skb, NFTA_TUNNEL_KEY_VXLAN_GBP,
+                                 htonl(opts->u.vxlan.gbp)))
+                        return -1;
+        } else if (opts->flags & TUNNEL_ERSPAN_OPT) {
+                switch (opts->u.erspan.version) {
+                case ERSPAN_VERSION:
+                        if (nla_put_be32(skb, NFTA_TUNNEL_KEY_ERSPAN_V1_INDEX,
+                                         opts->u.erspan.u.index))
+                                return -1;
+                        break;
+                case ERSPAN_VERSION2:
+                        if (nla_put_u8(skb, NFTA_TUNNEL_KEY_ERSPAN_V2_HWID,
+                                       get_hwid(&opts->u.erspan.u.md2)) ||
+                            nla_put_u8(skb, NFTA_TUNNEL_KEY_ERSPAN_V2_DIR,
+                                       opts->u.erspan.u.md2.dir))
+                                return -1;
+                        break;
+                }
+        }
+        nla_nest_end(skb, nest);
+
+        return 0;
+}
+
+static int nft_tunnel_ports_dump(struct sk_buff *skb,
+                                 struct ip_tunnel_info *info)
+{
+        if (nla_put_be16(skb, NFTA_TUNNEL_KEY_SPORT, htons(info->key.tp_src)) < 0 ||
+            nla_put_be16(skb, NFTA_TUNNEL_KEY_DPORT, htons(info->key.tp_dst)) < 0)
+                return -1;
+
+        return 0;
+}
+
+static int nft_tunnel_flags_dump(struct sk_buff *skb,
+                                 struct ip_tunnel_info *info)
+{
+        u32 flags = 0;
+
+        if (info->key.tun_flags & TUNNEL_DONT_FRAGMENT)
+                flags |= NFT_TUNNEL_F_DONT_FRAGMENT;
+        if (!(info->key.tun_flags & TUNNEL_CSUM))
+                flags |= NFT_TUNNEL_F_ZERO_CSUM_TX;
+        if (info->key.tun_flags & TUNNEL_SEQ)
+                flags |= NFT_TUNNEL_F_SEQ_NUMBER;
+
+        if (nla_put_be32(skb, NFTA_TUNNEL_KEY_FLAGS, htonl(flags)) < 0)
+                return -1;
+
+        return 0;
+}
+
+static int nft_tunnel_obj_dump(struct sk_buff *skb,
+                               struct nft_object *obj, bool reset)
+{
+        struct nft_tunnel_obj *priv = nft_obj_data(obj);
+        struct ip_tunnel_info *info = &priv->md->u.tun_info;
+
+        if (nla_put_be32(skb, NFTA_TUNNEL_KEY_ID,
+                         tunnel_id_to_key32(info->key.tun_id)) ||
+            nft_tunnel_ip_dump(skb, info) < 0 ||
+            nft_tunnel_ports_dump(skb, info) < 0 ||
+            nft_tunnel_flags_dump(skb, info) < 0 ||
+            nla_put_u8(skb, NFTA_TUNNEL_KEY_TOS, info->key.tos) ||
+            nla_put_u8(skb, NFTA_TUNNEL_KEY_TTL, info->key.ttl) ||
+            nft_tunnel_opts_dump(skb, priv) < 0)
+                goto nla_put_failure;
+
+        return 0;
+
+nla_put_failure:
+        return -1;
+}
+
+static void nft_tunnel_obj_destroy(const struct nft_ctx *ctx,
+                                   struct nft_object *obj)
+{
+        struct nft_tunnel_obj *priv = nft_obj_data(obj);
+
+        metadata_dst_free(priv->md);
+}
+
+static struct nft_object_type nft_tunnel_obj_type;
+static const struct nft_object_ops nft_tunnel_obj_ops = {
+        .type           = &nft_tunnel_obj_type,
+        .size           = sizeof(struct nft_tunnel_obj),
+        .eval           = nft_tunnel_obj_eval,
+        .init           = nft_tunnel_obj_init,
+        .destroy        = nft_tunnel_obj_destroy,
+        .dump           = nft_tunnel_obj_dump,
+};
+
+static struct nft_object_type nft_tunnel_obj_type __read_mostly = {
+        .type           = NFT_OBJECT_TUNNEL,
+        .ops            = &nft_tunnel_obj_ops,
+        .maxattr        = NFTA_TUNNEL_KEY_MAX,
+        .policy         = nft_tunnel_key_policy,
+        .owner          = THIS_MODULE,
+};
+
+static int __init nft_tunnel_module_init(void)
+{
+        return nft_register_obj(&nft_tunnel_obj_type);
+}
+
+static void __exit nft_tunnel_module_exit(void)
+{
+        nft_unregister_obj(&nft_tunnel_obj_type);
+}
+
+module_init(nft_tunnel_module_init);
+module_exit(nft_tunnel_module_exit);
+
+MODULE_LICENSE("GPL");
+MODULE_AUTHOR("Pablo Neira Ayuso <pablo@netfilter.org>");
+MODULE_ALIAS_NFT_OBJ(NFT_OBJECT_TUNNEL);