net/ipv4/ip_tunnel_core.c

   1 // SPDX-License-Identifier: GPL-2.0-only
   2 /*
   3  * Copyright (c) 2013 Nicira, Inc.
   4  */
   5
   6 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
   7
   8 #include <linux/types.h>
   9 #include <linux/kernel.h>
  10 #include <linux/skbuff.h>
  11 #include <linux/netdevice.h>
  12 #include <linux/in.h>
  13 #include <linux/if_arp.h>
  14 #include <linux/init.h>
  15 #include <linux/in6.h>
  16 #include <linux/inetdevice.h>
  17 #include <linux/netfilter_ipv4.h>
  18 #include <linux/etherdevice.h>
  19 #include <linux/if_ether.h>
  20 #include <linux/if_vlan.h>
  21 #include <linux/static_key.h>
  22
  23 #include <net/ip.h>
  24 #include <net/icmp.h>
  25 #include <net/protocol.h>
  26 #include <net/ip_tunnels.h>
  27 #include <net/ip6_tunnel.h>
  28 #include <net/arp.h>
  29 #include <net/checksum.h>
  30 #include <net/dsfield.h>
  31 #include <net/inet_ecn.h>
  32 #include <net/xfrm.h>
  33 #include <net/net_namespace.h>
  34 #include <net/netns/generic.h>
  35 #include <net/rtnetlink.h>
  36 #include <net/dst_metadata.h>
  37 #include <net/geneve.h>
  38 #include <net/vxlan.h>
  39 #include <net/erspan.h>
  40
  41 const struct ip_tunnel_encap_ops __rcu *
  42                 iptun_encaps[MAX_IPTUN_ENCAP_OPS] __read_mostly;
  43 EXPORT_SYMBOL(iptun_encaps);
  44
  45 const struct ip6_tnl_encap_ops __rcu *
  46                 ip6tun_encaps[MAX_IPTUN_ENCAP_OPS] __read_mostly;
  47 EXPORT_SYMBOL(ip6tun_encaps);
  48
  49 void iptunnel_xmit(struct sock *sk, struct rtable *rt, struct sk_buff *skb,
  50                    __be32 src, __be32 dst, __u8 proto,
  51                    __u8 tos, __u8 ttl, __be16 df, bool xnet)
  52 {
  53         int pkt_len = skb->len - skb_inner_network_offset(skb);
  54         struct net *net = dev_net(rt->dst.dev);
  55         struct net_device *dev = skb->dev;
  56         struct iphdr *iph;
  57         int err;
  58
  59         skb_scrub_packet(skb, xnet);
  60
  61         skb_clear_hash_if_not_l4(skb);
  62         skb_dst_set(skb, &rt->dst);
  63         memset(IPCB(skb), 0, sizeof(*IPCB(skb)));
  64
  65         /* Push down and install the IP header. */
  66         skb_push(skb, sizeof(struct iphdr));
  67         skb_reset_network_header(skb);
  68
  69         iph = ip_hdr(skb);
  70
  71         iph->version    =       4;
  72         iph->ihl        =       sizeof(struct iphdr) >> 2;
  73         iph->frag_off   =       ip_mtu_locked(&rt->dst) ? 0 : df;
  74         iph->protocol   =       proto;
  75         iph->tos        =       tos;
  76         iph->daddr      =       dst;
  77         iph->saddr      =       src;
  78         iph->ttl        =       ttl;
  79         __ip_select_ident(net, iph, skb_shinfo(skb)->gso_segs ?: 1);
  80
  81         err = ip_local_out(net, sk, skb);
  82
  83         if (dev) {
  84                 if (unlikely(net_xmit_eval(err)))
  85                         pkt_len = 0;
  86                 iptunnel_xmit_stats(dev, pkt_len);
  87         }
  88 }
  89 EXPORT_SYMBOL_GPL(iptunnel_xmit);
  90
  91 int __iptunnel_pull_header(struct sk_buff *skb, int hdr_len,
  92                            __be16 inner_proto, bool raw_proto, bool xnet)
  93 {
  94         if (unlikely(!pskb_may_pull(skb, hdr_len)))
  95                 return -ENOMEM;
  96
  97         skb_pull_rcsum(skb, hdr_len);
  98
  99         if (!raw_proto && inner_proto == htons(ETH_P_TEB)) {
 100                 struct ethhdr *eh;
 101
 102                 if (unlikely(!pskb_may_pull(skb, ETH_HLEN)))
 103                         return -ENOMEM;
 104
 105                 eh = (struct ethhdr *)skb->data;
 106                 if (likely(eth_proto_is_802_3(eh->h_proto)))
 107                         skb->protocol = eh->h_proto;
 108                 else
 109                         skb->protocol = htons(ETH_P_802_2);
 110
 111         } else {
 112                 skb->protocol = inner_proto;
 113         }
 114
 115         skb_clear_hash_if_not_l4(skb);
 116         __vlan_hwaccel_clear_tag(skb);
 117         skb_set_queue_mapping(skb, 0);
 118         skb_scrub_packet(skb, xnet);
 119
 120         return iptunnel_pull_offloads(skb);
 121 }
 122 EXPORT_SYMBOL_GPL(__iptunnel_pull_header);
 123
 124 struct metadata_dst *iptunnel_metadata_reply(struct metadata_dst *md,
 125                                              gfp_t flags)
 126 {
 127         struct metadata_dst *res;
 128         struct ip_tunnel_info *dst, *src;
 129
 130         if (!md || md->type != METADATA_IP_TUNNEL ||
 131             md->u.tun_info.mode & IP_TUNNEL_INFO_TX)
 132                 return NULL;
 133
 134         src = &md->u.tun_info;
 135         res = metadata_dst_alloc(src->options_len, METADATA_IP_TUNNEL, flags);
 136         if (!res)
 137                 return NULL;
 138
 139         dst = &res->u.tun_info;
 140         dst->key.tun_id = src->key.tun_id;
 141         if (src->mode & IP_TUNNEL_INFO_IPV6)
 142                 memcpy(&dst->key.u.ipv6.dst, &src->key.u.ipv6.src,
 143                        sizeof(struct in6_addr));
 144         else
 145                 dst->key.u.ipv4.dst = src->key.u.ipv4.src;
 146         dst->key.tun_flags = src->key.tun_flags;
 147         dst->mode = src->mode | IP_TUNNEL_INFO_TX;
 148         ip_tunnel_info_opts_set(dst, ip_tunnel_info_opts(src),
 149                                 src->options_len, 0);
 150
 151         return res;
 152 }
 153 EXPORT_SYMBOL_GPL(iptunnel_metadata_reply);
 154
 155 int iptunnel_handle_offloads(struct sk_buff *skb,
 156                              int gso_type_mask)
 157 {
 158         int err;
 159
 160         if (likely(!skb->encapsulation)) {
 161                 skb_reset_inner_headers(skb);
 162                 skb->encapsulation = 1;
 163         }
 164
 165         if (skb_is_gso(skb)) {
 166                 err = skb_header_unclone(skb, GFP_ATOMIC);
 167                 if (unlikely(err))
 168                         return err;
 169                 skb_shinfo(skb)->gso_type |= gso_type_mask;
 170                 return 0;
 171         }
 172
 173         if (skb->ip_summed != CHECKSUM_PARTIAL) {
 174                 skb->ip_summed = CHECKSUM_NONE;
 175                 /* We clear encapsulation here to prevent badly-written
 176                  * drivers potentially deciding to offload an inner checksum
 177                  * if we set CHECKSUM_PARTIAL on the outer header.
 178                  * This should go away when the drivers are all fixed.
 179                  */
 180                 skb->encapsulation = 0;
 181         }
 182
 183         return 0;
 184 }
 185 EXPORT_SYMBOL_GPL(iptunnel_handle_offloads);
 186
 187 /* Often modified stats are per cpu, other are shared (netdev->stats) */
 188 void ip_tunnel_get_stats64(struct net_device *dev,
 189                            struct rtnl_link_stats64 *tot)
 190 {
 191         int i;
 192
 193         netdev_stats_to_stats64(tot, &dev->stats);
 194
 195         for_each_possible_cpu(i) {
 196                 const struct pcpu_sw_netstats *tstats =
 197                                                    per_cpu_ptr(dev->tstats, i);
 198                 u64 rx_packets, rx_bytes, tx_packets, tx_bytes;
 199                 unsigned int start;
 200
 201                 do {
 202                         start = u64_stats_fetch_begin_irq(&tstats->syncp);
 203                         rx_packets = tstats->rx_packets;
 204                         tx_packets = tstats->tx_packets;
 205                         rx_bytes = tstats->rx_bytes;
 206                         tx_bytes = tstats->tx_bytes;
 207                 } while (u64_stats_fetch_retry_irq(&tstats->syncp, start));
 208
 209                 tot->rx_packets += rx_packets;
 210                 tot->tx_packets += tx_packets;
 211                 tot->rx_bytes   += rx_bytes;
 212                 tot->tx_bytes   += tx_bytes;
 213         }
 214 }
 215 EXPORT_SYMBOL_GPL(ip_tunnel_get_stats64);
 216
 217 static const struct nla_policy ip_tun_policy[LWTUNNEL_IP_MAX + 1] = {
 218         [LWTUNNEL_IP_UNSPEC]    = { .strict_start_type = LWTUNNEL_IP_OPTS },
 219         [LWTUNNEL_IP_ID]        = { .type = NLA_U64 },
 220         [LWTUNNEL_IP_DST]       = { .type = NLA_U32 },
 221         [LWTUNNEL_IP_SRC]       = { .type = NLA_U32 },
 222         [LWTUNNEL_IP_TTL]       = { .type = NLA_U8 },
 223         [LWTUNNEL_IP_TOS]       = { .type = NLA_U8 },
 224         [LWTUNNEL_IP_FLAGS]     = { .type = NLA_U16 },
 225         [LWTUNNEL_IP_OPTS]      = { .type = NLA_NESTED },
 226 };
 227
 228 static const struct nla_policy ip_opts_policy[LWTUNNEL_IP_OPTS_MAX + 1] = {
 229         [LWTUNNEL_IP_OPTS_GENEVE]       = { .type = NLA_NESTED },
 230         [LWTUNNEL_IP_OPTS_VXLAN]        = { .type = NLA_NESTED },
 231         [LWTUNNEL_IP_OPTS_ERSPAN]       = { .type = NLA_NESTED },
 232 };
 233
 234 static const struct nla_policy
 235 geneve_opt_policy[LWTUNNEL_IP_OPT_GENEVE_MAX + 1] = {
 236         [LWTUNNEL_IP_OPT_GENEVE_CLASS]  = { .type = NLA_U16 },
 237         [LWTUNNEL_IP_OPT_GENEVE_TYPE]   = { .type = NLA_U8 },
 238         [LWTUNNEL_IP_OPT_GENEVE_DATA]   = { .type = NLA_BINARY, .len = 128 },
 239 };
 240
 241 static const struct nla_policy
 242 vxlan_opt_policy[LWTUNNEL_IP_OPT_VXLAN_MAX + 1] = {
 243         [LWTUNNEL_IP_OPT_VXLAN_GBP]     = { .type = NLA_U32 },
 244 };
 245
 246 static const struct nla_policy
 247 erspan_opt_policy[LWTUNNEL_IP_OPT_ERSPAN_MAX + 1] = {
 248         [LWTUNNEL_IP_OPT_ERSPAN_VER]    = { .type = NLA_U8 },
 249         [LWTUNNEL_IP_OPT_ERSPAN_INDEX]  = { .type = NLA_U32 },
 250         [LWTUNNEL_IP_OPT_ERSPAN_DIR]    = { .type = NLA_U8 },
 251         [LWTUNNEL_IP_OPT_ERSPAN_HWID]   = { .type = NLA_U8 },
 252 };
 253
 254 static int ip_tun_parse_opts_geneve(struct nlattr *attr,
 255                                     struct ip_tunnel_info *info, int opts_len,
 256                                     struct netlink_ext_ack *extack)
 257 {
 258         struct nlattr *tb[LWTUNNEL_IP_OPT_GENEVE_MAX + 1];
 259         int data_len, err;
 260
 261         err = nla_parse_nested(tb, LWTUNNEL_IP_OPT_GENEVE_MAX, attr,
 262                                geneve_opt_policy, extack);
 263         if (err)
 264                 return err;
 265
 266         if (!tb[LWTUNNEL_IP_OPT_GENEVE_CLASS] ||
 267             !tb[LWTUNNEL_IP_OPT_GENEVE_TYPE] ||
 268             !tb[LWTUNNEL_IP_OPT_GENEVE_DATA])
 269                 return -EINVAL;
 270
 271         attr = tb[LWTUNNEL_IP_OPT_GENEVE_DATA];
 272         data_len = nla_len(attr);
 273         if (data_len % 4)
 274                 return -EINVAL;
 275
 276         if (info) {
 277                 struct geneve_opt *opt = ip_tunnel_info_opts(info) + opts_len;
 278
 279                 memcpy(opt->opt_data, nla_data(attr), data_len);
 280                 opt->length = data_len / 4;
 281                 attr = tb[LWTUNNEL_IP_OPT_GENEVE_CLASS];
 282                 opt->opt_class = nla_get_be16(attr);
 283                 attr = tb[LWTUNNEL_IP_OPT_GENEVE_TYPE];
 284                 opt->type = nla_get_u8(attr);
 285                 info->key.tun_flags |= TUNNEL_GENEVE_OPT;
 286         }
 287
 288         return sizeof(struct geneve_opt) + data_len;
 289 }
 290
 291 static int ip_tun_parse_opts_vxlan(struct nlattr *attr,
 292                                    struct ip_tunnel_info *info, int opts_len,
 293                                    struct netlink_ext_ack *extack)
 294 {
 295         struct nlattr *tb[LWTUNNEL_IP_OPT_VXLAN_MAX + 1];
 296         int err;
 297
 298         err = nla_parse_nested(tb, LWTUNNEL_IP_OPT_VXLAN_MAX, attr,
 299                                vxlan_opt_policy, extack);
 300         if (err)
 301                 return err;
 302
 303         if (!tb[LWTUNNEL_IP_OPT_VXLAN_GBP])
 304                 return -EINVAL;
 305
 306         if (info) {
 307                 struct vxlan_metadata *md =
 308                         ip_tunnel_info_opts(info) + opts_len;
 309
 310                 attr = tb[LWTUNNEL_IP_OPT_VXLAN_GBP];
 311                 md->gbp = nla_get_u32(attr);
 312                 info->key.tun_flags |= TUNNEL_VXLAN_OPT;
 313         }
 314
 315         return sizeof(struct vxlan_metadata);
 316 }
 317
 318 static int ip_tun_parse_opts_erspan(struct nlattr *attr,
 319                                     struct ip_tunnel_info *info, int opts_len,
 320                                     struct netlink_ext_ack *extack)
 321 {
 322         struct nlattr *tb[LWTUNNEL_IP_OPT_ERSPAN_MAX + 1];
 323         int err;
 324         u8 ver;
 325
 326         err = nla_parse_nested(tb, LWTUNNEL_IP_OPT_ERSPAN_MAX, attr,
 327                                erspan_opt_policy, extack);
 328         if (err)
 329                 return err;
 330
 331         if (!tb[LWTUNNEL_IP_OPT_ERSPAN_VER])
 332                 return -EINVAL;
 333
 334         ver = nla_get_u8(tb[LWTUNNEL_IP_OPT_ERSPAN_VER]);
 335         if (ver == 1) {
 336                 if (!tb[LWTUNNEL_IP_OPT_ERSPAN_INDEX])
 337                         return -EINVAL;
 338         } else if (ver == 2) {
 339                 if (!tb[LWTUNNEL_IP_OPT_ERSPAN_DIR] ||
 340                     !tb[LWTUNNEL_IP_OPT_ERSPAN_HWID])
 341                         return -EINVAL;
 342         } else {
 343                 return -EINVAL;
 344         }
 345
 346         if (info) {
 347                 struct erspan_metadata *md =
 348                         ip_tunnel_info_opts(info) + opts_len;
 349
 350                 md->version = ver;
 351                 if (ver == 1) {
 352                         attr = tb[LWTUNNEL_IP_OPT_ERSPAN_INDEX];
 353                         md->u.index = nla_get_be32(attr);
 354                 } else {
 355                         attr = tb[LWTUNNEL_IP_OPT_ERSPAN_DIR];
 356                         md->u.md2.dir = nla_get_u8(attr);
 357                         attr = tb[LWTUNNEL_IP_OPT_ERSPAN_HWID];
 358                         set_hwid(&md->u.md2, nla_get_u8(attr));
 359                 }
 360
 361                 info->key.tun_flags |= TUNNEL_ERSPAN_OPT;
 362         }
 363
 364         return sizeof(struct erspan_metadata);
 365 }
 366
 367 static int ip_tun_parse_opts(struct nlattr *attr, struct ip_tunnel_info *info,
 368                              struct netlink_ext_ack *extack)
 369 {
 370         int err, rem, opt_len, opts_len = 0, type = 0;
 371         struct nlattr *nla;
 372
 373         if (!attr)
 374                 return 0;
 375
 376         err = nla_validate(nla_data(attr), nla_len(attr), LWTUNNEL_IP_OPTS_MAX,
 377                            ip_opts_policy, extack);
 378         if (err)
 379                 return err;
 380
 381         nla_for_each_attr(nla, nla_data(attr), nla_len(attr), rem) {
 382                 switch (nla_type(nla)) {
 383                 case LWTUNNEL_IP_OPTS_GENEVE:
 384                         if (type && type != TUNNEL_GENEVE_OPT)
 385                                 return -EINVAL;
 386                         opt_len = ip_tun_parse_opts_geneve(nla, info, opts_len,
 387                                                            extack);
 388                         if (opt_len < 0)
 389                                 return opt_len;
 390                         opts_len += opt_len;
 391                         if (opts_len > IP_TUNNEL_OPTS_MAX)
 392                                 return -EINVAL;
 393                         type = TUNNEL_GENEVE_OPT;
 394                         break;
 395                 case LWTUNNEL_IP_OPTS_VXLAN:
 396                         if (type)
 397                                 return -EINVAL;
 398                         opt_len = ip_tun_parse_opts_vxlan(nla, info, opts_len,
 399                                                           extack);
 400                         if (opt_len < 0)
 401                                 return opt_len;
 402                         opts_len += opt_len;
 403                         type = TUNNEL_VXLAN_OPT;
 404                         break;
 405                 case LWTUNNEL_IP_OPTS_ERSPAN:
 406                         if (type)
 407                                 return -EINVAL;
 408                         opt_len = ip_tun_parse_opts_erspan(nla, info, opts_len,
 409                                                            extack);
 410                         if (opt_len < 0)
 411                                 return opt_len;
 412                         opts_len += opt_len;
 413                         type = TUNNEL_ERSPAN_OPT;
 414                         break;
 415                 default:
 416                         return -EINVAL;
 417                 }
 418         }
 419
 420         return opts_len;
 421 }
 422
 423 static int ip_tun_get_optlen(struct nlattr *attr,
 424                              struct netlink_ext_ack *extack)
 425 {
 426         return ip_tun_parse_opts(attr, NULL, extack);
 427 }
 428
 429 static int ip_tun_set_opts(struct nlattr *attr, struct ip_tunnel_info *info,
 430                            struct netlink_ext_ack *extack)
 431 {
 432         return ip_tun_parse_opts(attr, info, extack);
 433 }
 434
 435 static int ip_tun_build_state(struct nlattr *attr,
 436                               unsigned int family, const void *cfg,
 437                               struct lwtunnel_state **ts,
 438                               struct netlink_ext_ack *extack)
 439 {
 440         struct nlattr *tb[LWTUNNEL_IP_MAX + 1];
 441         struct lwtunnel_state *new_state;
 442         struct ip_tunnel_info *tun_info;
 443         int err, opt_len;
 444
 445         err = nla_parse_nested_deprecated(tb, LWTUNNEL_IP_MAX, attr,
 446                                           ip_tun_policy, extack);
 447         if (err < 0)
 448                 return err;
 449
 450         opt_len = ip_tun_get_optlen(tb[LWTUNNEL_IP_OPTS], extack);
 451         if (opt_len < 0)
 452                 return opt_len;
 453
 454         new_state = lwtunnel_state_alloc(sizeof(*tun_info) + opt_len);
 455         if (!new_state)
 456                 return -ENOMEM;
 457
 458         new_state->type = LWTUNNEL_ENCAP_IP;
 459
 460         tun_info = lwt_tun_info(new_state);
 461
 462         err = ip_tun_set_opts(tb[LWTUNNEL_IP_OPTS], tun_info, extack);
 463         if (err < 0) {
 464                 lwtstate_free(new_state);
 465                 return err;
 466         }
 467
 468 #ifdef CONFIG_DST_CACHE
 469         err = dst_cache_init(&tun_info->dst_cache, GFP_KERNEL);
 470         if (err) {
 471                 lwtstate_free(new_state);
 472                 return err;
 473         }
 474 #endif
 475
 476         if (tb[LWTUNNEL_IP_ID])
 477                 tun_info->key.tun_id = nla_get_be64(tb[LWTUNNEL_IP_ID]);
 478
 479         if (tb[LWTUNNEL_IP_DST])
 480                 tun_info->key.u.ipv4.dst = nla_get_in_addr(tb[LWTUNNEL_IP_DST]);
 481
 482         if (tb[LWTUNNEL_IP_SRC])
 483                 tun_info->key.u.ipv4.src = nla_get_in_addr(tb[LWTUNNEL_IP_SRC]);
 484
 485         if (tb[LWTUNNEL_IP_TTL])
 486                 tun_info->key.ttl = nla_get_u8(tb[LWTUNNEL_IP_TTL]);
 487
 488         if (tb[LWTUNNEL_IP_TOS])
 489                 tun_info->key.tos = nla_get_u8(tb[LWTUNNEL_IP_TOS]);
 490
 491         if (tb[LWTUNNEL_IP_FLAGS])
 492                 tun_info->key.tun_flags |=
 493                                 (nla_get_be16(tb[LWTUNNEL_IP_FLAGS]) &
 494                                  ~TUNNEL_OPTIONS_PRESENT);
 495
 496         tun_info->mode = IP_TUNNEL_INFO_TX;
 497         tun_info->options_len = opt_len;
 498
 499         *ts = new_state;
 500
 501         return 0;
 502 }
 503
 504 static void ip_tun_destroy_state(struct lwtunnel_state *lwtstate)
 505 {
 506 #ifdef CONFIG_DST_CACHE
 507         struct ip_tunnel_info *tun_info = lwt_tun_info(lwtstate);
 508
 509         dst_cache_destroy(&tun_info->dst_cache);
 510 #endif
 511 }
 512
 513 static int ip_tun_fill_encap_opts_geneve(struct sk_buff *skb,
 514                                          struct ip_tunnel_info *tun_info)
 515 {
 516         struct geneve_opt *opt;
 517         struct nlattr *nest;
 518         int offset = 0;
 519
 520         nest = nla_nest_start_noflag(skb, LWTUNNEL_IP_OPTS_GENEVE);
 521         if (!nest)
 522                 return -ENOMEM;
 523
 524         while (tun_info->options_len > offset) {
 525                 opt = ip_tunnel_info_opts(tun_info) + offset;
 526                 if (nla_put_be16(skb, LWTUNNEL_IP_OPT_GENEVE_CLASS,
 527                                  opt->opt_class) ||
 528                     nla_put_u8(skb, LWTUNNEL_IP_OPT_GENEVE_TYPE, opt->type) ||
 529                     nla_put(skb, LWTUNNEL_IP_OPT_GENEVE_DATA, opt->length * 4,
 530                             opt->opt_data)) {
 531                         nla_nest_cancel(skb, nest);
 532                         return -ENOMEM;
 533                 }
 534                 offset += sizeof(*opt) + opt->length * 4;
 535         }
 536
 537         nla_nest_end(skb, nest);
 538         return 0;
 539 }
 540
 541 static int ip_tun_fill_encap_opts_vxlan(struct sk_buff *skb,
 542                                         struct ip_tunnel_info *tun_info)
 543 {
 544         struct vxlan_metadata *md;
 545         struct nlattr *nest;
 546
 547         nest = nla_nest_start_noflag(skb, LWTUNNEL_IP_OPTS_VXLAN);
 548         if (!nest)
 549                 return -ENOMEM;
 550
 551         md = ip_tunnel_info_opts(tun_info);
 552         if (nla_put_u32(skb, LWTUNNEL_IP_OPT_VXLAN_GBP, md->gbp)) {
 553                 nla_nest_cancel(skb, nest);
 554                 return -ENOMEM;
 555         }
 556
 557         nla_nest_end(skb, nest);
 558         return 0;
 559 }
 560
 561 static int ip_tun_fill_encap_opts_erspan(struct sk_buff *skb,
 562                                          struct ip_tunnel_info *tun_info)
 563 {
 564         struct erspan_metadata *md;
 565         struct nlattr *nest;
 566
 567         nest = nla_nest_start_noflag(skb, LWTUNNEL_IP_OPTS_ERSPAN);
 568         if (!nest)
 569                 return -ENOMEM;
 570
 571         md = ip_tunnel_info_opts(tun_info);
 572         if (nla_put_u8(skb, LWTUNNEL_IP_OPT_ERSPAN_VER, md->version))
 573                 goto err;
 574
 575         if (md->version == 1 &&
 576             nla_put_be32(skb, LWTUNNEL_IP_OPT_ERSPAN_INDEX, md->u.index))
 577                 goto err;
 578
 579         if (md->version == 2 &&
 580             (nla_put_u8(skb, LWTUNNEL_IP_OPT_ERSPAN_DIR, md->u.md2.dir) ||
 581              nla_put_u8(skb, LWTUNNEL_IP_OPT_ERSPAN_HWID,
 582                         get_hwid(&md->u.md2))))
 583                 goto err;
 584
 585         nla_nest_end(skb, nest);
 586         return 0;
 587 err:
 588         nla_nest_cancel(skb, nest);
 589         return -ENOMEM;
 590 }
 591
 592 static int ip_tun_fill_encap_opts(struct sk_buff *skb, int type,
 593                                   struct ip_tunnel_info *tun_info)
 594 {
 595         struct nlattr *nest;
 596         int err = 0;
 597
 598         if (!(tun_info->key.tun_flags & TUNNEL_OPTIONS_PRESENT))
 599                 return 0;
 600
 601         nest = nla_nest_start_noflag(skb, type);
 602         if (!nest)
 603                 return -ENOMEM;
 604
 605         if (tun_info->key.tun_flags & TUNNEL_GENEVE_OPT)
 606                 err = ip_tun_fill_encap_opts_geneve(skb, tun_info);
 607         else if (tun_info->key.tun_flags & TUNNEL_VXLAN_OPT)
 608                 err = ip_tun_fill_encap_opts_vxlan(skb, tun_info);
 609         else if (tun_info->key.tun_flags & TUNNEL_ERSPAN_OPT)
 610                 err = ip_tun_fill_encap_opts_erspan(skb, tun_info);
 611
 612         if (err) {
 613                 nla_nest_cancel(skb, nest);
 614                 return err;
 615         }
 616
 617         nla_nest_end(skb, nest);
 618         return 0;
 619 }
 620
 621 static int ip_tun_fill_encap_info(struct sk_buff *skb,
 622                                   struct lwtunnel_state *lwtstate)
 623 {
 624         struct ip_tunnel_info *tun_info = lwt_tun_info(lwtstate);
 625
 626         if (nla_put_be64(skb, LWTUNNEL_IP_ID, tun_info->key.tun_id,
 627                          LWTUNNEL_IP_PAD) ||
 628             nla_put_in_addr(skb, LWTUNNEL_IP_DST, tun_info->key.u.ipv4.dst) ||
 629             nla_put_in_addr(skb, LWTUNNEL_IP_SRC, tun_info->key.u.ipv4.src) ||
 630             nla_put_u8(skb, LWTUNNEL_IP_TOS, tun_info->key.tos) ||
 631             nla_put_u8(skb, LWTUNNEL_IP_TTL, tun_info->key.ttl) ||
 632             nla_put_be16(skb, LWTUNNEL_IP_FLAGS, tun_info->key.tun_flags) ||
 633             ip_tun_fill_encap_opts(skb, LWTUNNEL_IP_OPTS, tun_info))
 634                 return -ENOMEM;
 635
 636         return 0;
 637 }
 638
 639 static int ip_tun_opts_nlsize(struct ip_tunnel_info *info)
 640 {
 641         int opt_len;
 642
 643         if (!(info->key.tun_flags & TUNNEL_OPTIONS_PRESENT))
 644                 return 0;
 645
 646         opt_len = nla_total_size(0);            /* LWTUNNEL_IP_OPTS */
 647         if (info->key.tun_flags & TUNNEL_GENEVE_OPT) {
 648                 struct geneve_opt *opt;
 649                 int offset = 0;
 650
 651                 opt_len += nla_total_size(0);   /* LWTUNNEL_IP_OPTS_GENEVE */
 652                 while (info->options_len > offset) {
 653                         opt = ip_tunnel_info_opts(info) + offset;
 654                         opt_len += nla_total_size(2)    /* OPT_GENEVE_CLASS */
 655                                    + nla_total_size(1)  /* OPT_GENEVE_TYPE */
 656                                    + nla_total_size(opt->length * 4);
 657                                                         /* OPT_GENEVE_DATA */
 658                         offset += sizeof(*opt) + opt->length * 4;
 659                 }
 660         } else if (info->key.tun_flags & TUNNEL_VXLAN_OPT) {
 661                 opt_len += nla_total_size(0)    /* LWTUNNEL_IP_OPTS_VXLAN */
 662                            + nla_total_size(4); /* OPT_VXLAN_GBP */
 663         } else if (info->key.tun_flags & TUNNEL_ERSPAN_OPT) {
 664                 struct erspan_metadata *md = ip_tunnel_info_opts(info);
 665
 666                 opt_len += nla_total_size(0)    /* LWTUNNEL_IP_OPTS_ERSPAN */
 667                            + nla_total_size(1)  /* OPT_ERSPAN_VER */
 668                            + (md->version == 1 ? nla_total_size(4)
 669                                                 /* OPT_ERSPAN_INDEX (v1) */
 670                                                : nla_total_size(1) +
 671                                                  nla_total_size(1));
 672                                                 /* OPT_ERSPAN_DIR + HWID (v2) */
 673         }
 674
 675         return opt_len;
 676 }
 677
 678 static int ip_tun_encap_nlsize(struct lwtunnel_state *lwtstate)
 679 {
 680         return nla_total_size_64bit(8)  /* LWTUNNEL_IP_ID */
 681                 + nla_total_size(4)     /* LWTUNNEL_IP_DST */
 682                 + nla_total_size(4)     /* LWTUNNEL_IP_SRC */
 683                 + nla_total_size(1)     /* LWTUNNEL_IP_TOS */
 684                 + nla_total_size(1)     /* LWTUNNEL_IP_TTL */
 685                 + nla_total_size(2)     /* LWTUNNEL_IP_FLAGS */
 686                 + ip_tun_opts_nlsize(lwt_tun_info(lwtstate));
 687                                         /* LWTUNNEL_IP_OPTS */
 688 }
 689
 690 static int ip_tun_cmp_encap(struct lwtunnel_state *a, struct lwtunnel_state *b)
 691 {
 692         struct ip_tunnel_info *info_a = lwt_tun_info(a);
 693         struct ip_tunnel_info *info_b = lwt_tun_info(b);
 694
 695         return memcmp(info_a, info_b, sizeof(info_a->key)) ||
 696                info_a->mode != info_b->mode ||
 697                info_a->options_len != info_b->options_len ||
 698                memcmp(ip_tunnel_info_opts(info_a),
 699                       ip_tunnel_info_opts(info_b), info_a->options_len);
 700 }
 701
 702 static const struct lwtunnel_encap_ops ip_tun_lwt_ops = {
 703         .build_state = ip_tun_build_state,
 704         .destroy_state = ip_tun_destroy_state,
 705         .fill_encap = ip_tun_fill_encap_info,
 706         .get_encap_size = ip_tun_encap_nlsize,
 707         .cmp_encap = ip_tun_cmp_encap,
 708         .owner = THIS_MODULE,
 709 };
 710
 711 static const struct nla_policy ip6_tun_policy[LWTUNNEL_IP6_MAX + 1] = {
 712         [LWTUNNEL_IP6_UNSPEC]   = { .strict_start_type = LWTUNNEL_IP6_OPTS },
 713         [LWTUNNEL_IP6_ID]               = { .type = NLA_U64 },
 714         [LWTUNNEL_IP6_DST]              = { .len = sizeof(struct in6_addr) },
 715         [LWTUNNEL_IP6_SRC]              = { .len = sizeof(struct in6_addr) },
 716         [LWTUNNEL_IP6_HOPLIMIT]         = { .type = NLA_U8 },
 717         [LWTUNNEL_IP6_TC]               = { .type = NLA_U8 },
 718         [LWTUNNEL_IP6_FLAGS]            = { .type = NLA_U16 },
 719         [LWTUNNEL_IP6_OPTS]             = { .type = NLA_NESTED },
 720 };
 721
 722 static int ip6_tun_build_state(struct nlattr *attr,
 723                                unsigned int family, const void *cfg,
 724                                struct lwtunnel_state **ts,
 725                                struct netlink_ext_ack *extack)
 726 {
 727         struct nlattr *tb[LWTUNNEL_IP6_MAX + 1];
 728         struct lwtunnel_state *new_state;
 729         struct ip_tunnel_info *tun_info;
 730         int err, opt_len;
 731
 732         err = nla_parse_nested_deprecated(tb, LWTUNNEL_IP6_MAX, attr,
 733                                           ip6_tun_policy, extack);
 734         if (err < 0)
 735                 return err;
 736
 737         opt_len = ip_tun_get_optlen(tb[LWTUNNEL_IP6_OPTS], extack);
 738         if (opt_len < 0)
 739                 return opt_len;
 740
 741         new_state = lwtunnel_state_alloc(sizeof(*tun_info) + opt_len);
 742         if (!new_state)
 743                 return -ENOMEM;
 744
 745         new_state->type = LWTUNNEL_ENCAP_IP6;
 746
 747         tun_info = lwt_tun_info(new_state);
 748
 749         err = ip_tun_set_opts(tb[LWTUNNEL_IP6_OPTS], tun_info, extack);
 750         if (err < 0) {
 751                 lwtstate_free(new_state);
 752                 return err;
 753         }
 754
 755         if (tb[LWTUNNEL_IP6_ID])
 756                 tun_info->key.tun_id = nla_get_be64(tb[LWTUNNEL_IP6_ID]);
 757
 758         if (tb[LWTUNNEL_IP6_DST])
 759                 tun_info->key.u.ipv6.dst = nla_get_in6_addr(tb[LWTUNNEL_IP6_DST]);
 760
 761         if (tb[LWTUNNEL_IP6_SRC])
 762                 tun_info->key.u.ipv6.src = nla_get_in6_addr(tb[LWTUNNEL_IP6_SRC]);
 763
 764         if (tb[LWTUNNEL_IP6_HOPLIMIT])
 765                 tun_info->key.ttl = nla_get_u8(tb[LWTUNNEL_IP6_HOPLIMIT]);
 766
 767         if (tb[LWTUNNEL_IP6_TC])
 768                 tun_info->key.tos = nla_get_u8(tb[LWTUNNEL_IP6_TC]);
 769
 770         if (tb[LWTUNNEL_IP6_FLAGS])
 771                 tun_info->key.tun_flags |=
 772                                 (nla_get_be16(tb[LWTUNNEL_IP6_FLAGS]) &
 773                                  ~TUNNEL_OPTIONS_PRESENT);
 774
 775         tun_info->mode = IP_TUNNEL_INFO_TX | IP_TUNNEL_INFO_IPV6;
 776         tun_info->options_len = opt_len;
 777
 778         *ts = new_state;
 779
 780         return 0;
 781 }
 782
 783 static int ip6_tun_fill_encap_info(struct sk_buff *skb,
 784                                    struct lwtunnel_state *lwtstate)
 785 {
 786         struct ip_tunnel_info *tun_info = lwt_tun_info(lwtstate);
 787
 788         if (nla_put_be64(skb, LWTUNNEL_IP6_ID, tun_info->key.tun_id,
 789                          LWTUNNEL_IP6_PAD) ||
 790             nla_put_in6_addr(skb, LWTUNNEL_IP6_DST, &tun_info->key.u.ipv6.dst) ||
 791             nla_put_in6_addr(skb, LWTUNNEL_IP6_SRC, &tun_info->key.u.ipv6.src) ||
 792             nla_put_u8(skb, LWTUNNEL_IP6_TC, tun_info->key.tos) ||
 793             nla_put_u8(skb, LWTUNNEL_IP6_HOPLIMIT, tun_info->key.ttl) ||
 794             nla_put_be16(skb, LWTUNNEL_IP6_FLAGS, tun_info->key.tun_flags) ||
 795             ip_tun_fill_encap_opts(skb, LWTUNNEL_IP6_OPTS, tun_info))
 796                 return -ENOMEM;
 797
 798         return 0;
 799 }
 800
 801 static int ip6_tun_encap_nlsize(struct lwtunnel_state *lwtstate)
 802 {
 803         return nla_total_size_64bit(8)  /* LWTUNNEL_IP6_ID */
 804                 + nla_total_size(16)    /* LWTUNNEL_IP6_DST */
 805                 + nla_total_size(16)    /* LWTUNNEL_IP6_SRC */
 806                 + nla_total_size(1)     /* LWTUNNEL_IP6_HOPLIMIT */
 807                 + nla_total_size(1)     /* LWTUNNEL_IP6_TC */
 808                 + nla_total_size(2)     /* LWTUNNEL_IP6_FLAGS */
 809                 + ip_tun_opts_nlsize(lwt_tun_info(lwtstate));
 810                                         /* LWTUNNEL_IP6_OPTS */
 811 }
 812
 813 static const struct lwtunnel_encap_ops ip6_tun_lwt_ops = {
 814         .build_state = ip6_tun_build_state,
 815         .fill_encap = ip6_tun_fill_encap_info,
 816         .get_encap_size = ip6_tun_encap_nlsize,
 817         .cmp_encap = ip_tun_cmp_encap,
 818         .owner = THIS_MODULE,
 819 };
 820
 821 void __init ip_tunnel_core_init(void)
 822 {
 823         /* If you land here, make sure whether increasing ip_tunnel_info's
 824          * options_len is a reasonable choice with its usage in front ends
 825          * (f.e., it's part of flow keys, etc).
 826          */
 827         BUILD_BUG_ON(IP_TUNNEL_OPTS_MAX != 255);
 828
 829         lwtunnel_encap_add_ops(&ip_tun_lwt_ops, LWTUNNEL_ENCAP_IP);
 830         lwtunnel_encap_add_ops(&ip6_tun_lwt_ops, LWTUNNEL_ENCAP_IP6);
 831 }
 832
 833 DEFINE_STATIC_KEY_FALSE(ip_tunnel_metadata_cnt);
 834 EXPORT_SYMBOL(ip_tunnel_metadata_cnt);
 835
 836 void ip_tunnel_need_metadata(void)
 837 {
 838         static_branch_inc(&ip_tunnel_metadata_cnt);
 839 }
 840 EXPORT_SYMBOL_GPL(ip_tunnel_need_metadata);
 841
 842 void ip_tunnel_unneed_metadata(void)
 843 {
 844         static_branch_dec(&ip_tunnel_metadata_cnt);
 845 }
 846 EXPORT_SYMBOL_GPL(ip_tunnel_unneed_metadata);