target/linux/generic/patches-3.19/666-Add-support-for-MAP-E-FMRs-mesh-mode.patch

   1 From 775d6fe74d1eaec2ba387535b068dde2dc89de9e Mon Sep 17 00:00:00 2001
   2 From: Steven Barth <steven@midlink.org>
   3 Date: Thu, 22 May 2014 09:49:05 +0200
   4 Subject: [PATCH] Add support for MAP-E FMRs (mesh mode)
   5
   6 MAP-E FMRs (draft-ietf-softwire-map-10) are rules for IPv4-communication
   7 between MAP CEs (mesh mode) without the need to forward such data to a
   8 border relay. This is similar to how 6rd works but for IPv4 over IPv6.
   9
  10 Signed-off-by: Steven Barth <cyrus@openwrt.org>
  11 ---
  12  include/net/ip6_tunnel.h       |  13 ++
  13  include/uapi/linux/if_tunnel.h |  13 ++
  14  net/ipv6/ip6_tunnel.c          | 276 +++++++++++++++++++++++++++++++++++++++--
  15  3 files changed, 291 insertions(+), 11 deletions(-)
  16
  17 --- a/include/net/ip6_tunnel.h
  18 +++ b/include/net/ip6_tunnel.h
  19 @@ -15,6 +15,18 @@
  20  /* determine capability on a per-packet basis */
  21  #define IP6_TNL_F_CAP_PER_PACKET 0x40000
  22
  23 +/* IPv6 tunnel FMR */
  24 +struct __ip6_tnl_fmr {
  25 +       struct __ip6_tnl_fmr *next; /* next fmr in list */
  26 +       struct in6_addr ip6_prefix;
  27 +       struct in_addr ip4_prefix;
  28 +
  29 +       __u8 ip6_prefix_len;
  30 +       __u8 ip4_prefix_len;
  31 +       __u8 ea_len;
  32 +       __u8 offset;
  33 +};
  34 +
  35  struct __ip6_tnl_parm {
  36         char name[IFNAMSIZ];    /* name of tunnel device */
  37         int link;               /* ifindex of underlying L2 interface */
  38 @@ -25,6 +37,7 @@ struct __ip6_tnl_parm {
  39         __u32 flags;            /* tunnel flags */
  40         struct in6_addr laddr;  /* local tunnel end-point address */
  41         struct in6_addr raddr;  /* remote tunnel end-point address */
  42 +       struct __ip6_tnl_fmr *fmrs;     /* FMRs */
  43
  44         __be16                  i_flags;
  45         __be16                  o_flags;
  46 --- a/include/uapi/linux/if_tunnel.h
  47 +++ b/include/uapi/linux/if_tunnel.h
  48 @@ -57,10 +57,23 @@ enum {
  49         IFLA_IPTUN_ENCAP_FLAGS,
  50         IFLA_IPTUN_ENCAP_SPORT,
  51         IFLA_IPTUN_ENCAP_DPORT,
  52 +       IFLA_IPTUN_FMRS,
  53         __IFLA_IPTUN_MAX,
  54  };
  55  #define IFLA_IPTUN_MAX (__IFLA_IPTUN_MAX - 1)
  56
  57 +enum {
  58 +       IFLA_IPTUN_FMR_UNSPEC,
  59 +       IFLA_IPTUN_FMR_IP6_PREFIX,
  60 +       IFLA_IPTUN_FMR_IP4_PREFIX,
  61 +       IFLA_IPTUN_FMR_IP6_PREFIX_LEN,
  62 +       IFLA_IPTUN_FMR_IP4_PREFIX_LEN,
  63 +       IFLA_IPTUN_FMR_EA_LEN,
  64 +       IFLA_IPTUN_FMR_OFFSET,
  65 +       __IFLA_IPTUN_FMR_MAX,
  66 +};
  67 +#define IFLA_IPTUN_FMR_MAX (__IFLA_IPTUN_FMR_MAX - 1)
  68 +
  69  enum tunnel_encap_types {
  70         TUNNEL_ENCAP_NONE,
  71         TUNNEL_ENCAP_FOU,
  72 --- a/net/ipv6/ip6_tunnel.c
  73 +++ b/net/ipv6/ip6_tunnel.c
  74 @@ -16,6 +16,8 @@
  75   *      as published by the Free Software Foundation; either version
  76   *      2 of the License, or (at your option) any later version.
  77   *
  78 + *     Changes:
  79 + * Steven Barth <cyrus@openwrt.org>:           MAP-E FMR support
  80   */
  81
  82  #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
  83 @@ -77,11 +79,9 @@ static bool log_ecn_error = true;
  84  module_param(log_ecn_error, bool, 0644);
  85  MODULE_PARM_DESC(log_ecn_error, "Log packets received with corrupted ECN");
  86
  87 -static u32 HASH(const struct in6_addr *addr1, const struct in6_addr *addr2)
  88 +static u32 HASH(const struct in6_addr *addr)
  89  {
  90 -       u32 hash = ipv6_addr_hash(addr1) ^ ipv6_addr_hash(addr2);
  91 -
  92 -       return hash_32(hash, HASH_SIZE_SHIFT);
  93 +       return hash_32(ipv6_addr_hash(addr), HASH_SIZE_SHIFT);
  94  }
  95
  96  static int ip6_tnl_dev_init(struct net_device *dev);
  97 @@ -180,16 +180,24 @@ EXPORT_SYMBOL_GPL(ip6_tnl_dst_store);
  98  static struct ip6_tnl *
  99  ip6_tnl_lookup(struct net *net, const struct in6_addr *remote, const struct in6_addr *local)
 100  {
 101 -       unsigned int hash = HASH(remote, local);
 102 +       unsigned int hash = HASH(local);
 103         struct ip6_tnl *t;
 104         struct ip6_tnl_net *ip6n = net_generic(net, ip6_tnl_net_id);
 105 -       struct in6_addr any;
 106 +       struct __ip6_tnl_fmr *fmr;
 107
 108         for_each_ip6_tunnel_rcu(ip6n->tnls_r_l[hash]) {
 109 -               if (ipv6_addr_equal(local, &t->parms.laddr) &&
 110 -                   ipv6_addr_equal(remote, &t->parms.raddr) &&
 111 -                   (t->dev->flags & IFF_UP))
 112 +               if (!ipv6_addr_equal(local, &t->parms.laddr) ||
 113 +                               !(t->dev->flags & IFF_UP))
 114 +                       continue;
 115 +
 116 +               if (ipv6_addr_equal(remote, &t->parms.raddr))
 117                         return t;
 118 +
 119 +               for (fmr = t->parms.fmrs; fmr; fmr = fmr->next) {
 120 +                       if (ipv6_prefix_equal(remote, &fmr->ip6_prefix,
 121 +                                       fmr->ip6_prefix_len))
 122 +                               return t;
 123 +               }
 124         }
 125
 126         memset(&any, 0, sizeof(any));
 127 @@ -235,7 +243,7 @@ ip6_tnl_bucket(struct ip6_tnl_net *ip6n,
 128
 129         if (!ipv6_addr_any(remote) || !ipv6_addr_any(local)) {
 130                 prio = 1;
 131 -               h = HASH(remote, local);
 132 +               h = HASH(local);
 133         }
 134         return &ip6n->tnls[prio][h];
 135  }
 136 @@ -405,6 +413,12 @@ ip6_tnl_dev_uninit(struct net_device *de
 137         struct net *net = t->net;
 138         struct ip6_tnl_net *ip6n = net_generic(net, ip6_tnl_net_id);
 139
 140 +       while (t->parms.fmrs) {
 141 +               struct __ip6_tnl_fmr *next = t->parms.fmrs->next;
 142 +               kfree(t->parms.fmrs);
 143 +               t->parms.fmrs = next;
 144 +       }
 145 +
 146         if (dev == ip6n->fb_tnl_dev)
 147                 RCU_INIT_POINTER(ip6n->tnls_wc[0], NULL);
 148         else
 149 @@ -791,6 +805,108 @@ int ip6_tnl_rcv_ctl(struct ip6_tnl *t,
 150  }
 151  EXPORT_SYMBOL_GPL(ip6_tnl_rcv_ctl);
 152
 153 +
 154 +/**
 155 + * ip4ip6_fmr_calc - calculate target / source IPv6-address based on FMR
 156 + *   @dest: destination IPv6 address buffer
 157 + *   @skb: received socket buffer
 158 + *   @fmr: MAP FMR
 159 + *   @xmit: Calculate for xmit or rcv
 160 + **/
 161 +static void ip4ip6_fmr_calc(struct in6_addr *dest,
 162 +               const struct iphdr *iph, const uint8_t *end,
 163 +               const struct __ip6_tnl_fmr *fmr, bool xmit)
 164 +{
 165 +       int psidlen = fmr->ea_len - (32 - fmr->ip4_prefix_len);
 166 +       u8 *portp = NULL;
 167 +       bool use_dest_addr;
 168 +       const struct iphdr *dsth = iph;
 169 +
 170 +       if ((u8*)dsth >= end)
 171 +               return;
 172 +
 173 +       /* find significant IP header */
 174 +       if (iph->protocol == IPPROTO_ICMP) {
 175 +               struct icmphdr *ih = (struct icmphdr*)(((u8*)dsth) + dsth->ihl * 4);
 176 +               if (ih && ((u8*)&ih[1]) <= end && (
 177 +                       ih->type == ICMP_DEST_UNREACH ||
 178 +                       ih->type == ICMP_SOURCE_QUENCH ||
 179 +                       ih->type == ICMP_TIME_EXCEEDED ||
 180 +                       ih->type == ICMP_PARAMETERPROB ||
 181 +                       ih->type == ICMP_REDIRECT))
 182 +                               dsth = (const struct iphdr*)&ih[1];
 183 +       }
 184 +
 185 +       /* in xmit-path use dest port by default and source port only if
 186 +               this is an ICMP reply to something else; vice versa in rcv-path */
 187 +       use_dest_addr = (xmit && dsth == iph) || (!xmit && dsth != iph);
 188 +
 189 +       /* get dst port */
 190 +       if (((u8*)&dsth[1]) <= end && (
 191 +               dsth->protocol == IPPROTO_UDP ||
 192 +               dsth->protocol == IPPROTO_TCP ||
 193 +               dsth->protocol == IPPROTO_SCTP ||
 194 +               dsth->protocol == IPPROTO_DCCP)) {
 195 +                       /* for UDP, TCP, SCTP and DCCP source and dest port
 196 +                       follow IPv4 header directly */
 197 +                       portp = ((u8*)dsth) + dsth->ihl * 4;
 198 +
 199 +                       if (use_dest_addr)
 200 +                               portp += sizeof(u16);
 201 +       } else if (iph->protocol == IPPROTO_ICMP) {
 202 +               struct icmphdr *ih = (struct icmphdr*)(((u8*)dsth) + dsth->ihl * 4);
 203 +
 204 +               /* use icmp identifier as port */
 205 +               if (((u8*)&ih) <= end && (
 206 +                   (use_dest_addr && (
 207 +                   ih->type == ICMP_ECHOREPLY ||
 208 +                       ih->type == ICMP_TIMESTAMPREPLY ||
 209 +                       ih->type == ICMP_INFO_REPLY ||
 210 +                       ih->type == ICMP_ADDRESSREPLY)) ||
 211 +                       (!use_dest_addr && (
 212 +                       ih->type == ICMP_ECHO ||
 213 +                       ih->type == ICMP_TIMESTAMP ||
 214 +                       ih->type == ICMP_INFO_REQUEST ||
 215 +                       ih->type == ICMP_ADDRESS)
 216 +                       )))
 217 +                               portp = (u8*)&ih->un.echo.id;
 218 +       }
 219 +
 220 +       if ((portp && &portp[2] <= end) || psidlen == 0) {
 221 +               int frombyte = fmr->ip6_prefix_len / 8;
 222 +               int fromrem = fmr->ip6_prefix_len % 8;
 223 +               int bytes = sizeof(struct in6_addr) - frombyte;
 224 +               const u32 *addr = (use_dest_addr) ? &iph->daddr : &iph->saddr;
 225 +               u64 eabits = ((u64)ntohl(*addr)) << (32 + fmr->ip4_prefix_len);
 226 +               u64 t = 0;
 227 +
 228 +               /* extract PSID from port and add it to eabits */
 229 +               u16 psidbits = 0;
 230 +               if (psidlen > 0) {
 231 +                       psidbits = ((u16)portp[0]) << 8 | ((u16)portp[1]);
 232 +                       psidbits >>= 16 - psidlen - fmr->offset;
 233 +                       psidbits = (u16)(psidbits << (16 - psidlen));
 234 +                       eabits |= ((u64)psidbits) << (48 - (fmr->ea_len - psidlen));
 235 +               }
 236 +
 237 +               /* rewrite destination address */
 238 +               *dest = fmr->ip6_prefix;
 239 +               memcpy(&dest->s6_addr[10], addr, sizeof(*addr));
 240 +               dest->s6_addr16[7] = htons(psidbits >> (16 - psidlen));
 241 +
 242 +               if (bytes > sizeof(u64))
 243 +                       bytes = sizeof(u64);
 244 +
 245 +               /* insert eabits */
 246 +               memcpy(&t, &dest->s6_addr[frombyte], bytes);
 247 +               t = be64_to_cpu(t) & ~(((((u64)1) << fmr->ea_len) - 1)
 248 +                       << (64 - fmr->ea_len - fromrem));
 249 +               t = cpu_to_be64(t | (eabits >> fromrem));
 250 +               memcpy(&dest->s6_addr[frombyte], &t, bytes);
 251 +       }
 252 +}
 253 +
 254 +
 255  /**
 256   * ip6_tnl_rcv - decapsulate IPv6 packet and retransmit it locally
 257   *   @skb: received socket buffer
 258 @@ -836,6 +952,26 @@ static int ip6_tnl_rcv(struct sk_buff *s
 259                 skb_reset_network_header(skb);
 260                 skb->protocol = htons(protocol);
 261                 memset(skb->cb, 0, sizeof(struct inet6_skb_parm));
 262 +               if (protocol == ETH_P_IP &&
 263 +                       !ipv6_addr_equal(&ipv6h->saddr, &t->parms.raddr)) {
 264 +                               /* Packet didn't come from BR, so lookup FMR */
 265 +                               struct __ip6_tnl_fmr *fmr;
 266 +                               struct in6_addr expected = t->parms.raddr;
 267 +                               for (fmr = t->parms.fmrs; fmr; fmr = fmr->next)
 268 +                                       if (ipv6_prefix_equal(&ipv6h->saddr,
 269 +                                               &fmr->ip6_prefix, fmr->ip6_prefix_len))
 270 +                                                       break;
 271 +
 272 +                               /* Check that IPv6 matches IPv4 source to prevent spoofing */
 273 +                               if (fmr)
 274 +                                       ip4ip6_fmr_calc(&expected, ip_hdr(skb),
 275 +                                                       skb_tail_pointer(skb), fmr, false);
 276 +
 277 +                               if (!ipv6_addr_equal(&ipv6h->saddr, &expected)) {
 278 +                                       rcu_read_unlock();
 279 +                                       goto discard;
 280 +                               }
 281 +               }
 282
 283                 __skb_tunnel_rx(skb, t->dev, t->net);
 284
 285 @@ -1129,6 +1265,7 @@ ip4ip6_tnl_xmit(struct sk_buff *skb, str
 286         __u32 mtu;
 287         u8 tproto;
 288         int err;
 289 +       struct __ip6_tnl_fmr *fmr;
 290
 291         tproto = ACCESS_ONCE(t->parms.proto);
 292         if (tproto != IPPROTO_IPIP && tproto != 0)
 293 @@ -1148,6 +1285,18 @@ ip4ip6_tnl_xmit(struct sk_buff *skb, str
 294         if (t->parms.flags & IP6_TNL_F_USE_ORIG_FWMARK)
 295                 fl6.flowi6_mark = skb->mark;
 296
 297 +       /* try to find matching FMR */
 298 +       for (fmr = t->parms.fmrs; fmr; fmr = fmr->next) {
 299 +               unsigned mshift = 32 - fmr->ip4_prefix_len;
 300 +               if (ntohl(fmr->ip4_prefix.s_addr) >> mshift ==
 301 +                               ntohl(iph->daddr) >> mshift)
 302 +                       break;
 303 +       }
 304 +
 305 +       /* change dstaddr according to FMR */
 306 +       if (fmr)
 307 +               ip4ip6_fmr_calc(&fl6.daddr, iph, skb_tail_pointer(skb), fmr, true);
 308 +
 309         err = ip6_tnl_xmit2(skb, dev, dsfield, &fl6, encap_limit, &mtu);
 310         if (err != 0) {
 311                 /* XXX: send ICMP error even if DF is not set. */
 312 @@ -1318,6 +1467,14 @@ ip6_tnl_change(struct ip6_tnl *t, const
 313         t->parms.flowinfo = p->flowinfo;
 314         t->parms.link = p->link;
 315         t->parms.proto = p->proto;
 316 +
 317 +       while (t->parms.fmrs) {
 318 +               struct __ip6_tnl_fmr *next = t->parms.fmrs->next;
 319 +               kfree(t->parms.fmrs);
 320 +               t->parms.fmrs = next;
 321 +       }
 322 +       t->parms.fmrs = p->fmrs;
 323 +
 324         ip6_tnl_dst_reset(t);
 325         ip6_tnl_link_config(t);
 326         return 0;
 327 @@ -1356,6 +1513,7 @@ ip6_tnl_parm_from_user(struct __ip6_tnl_
 328         p->flowinfo = u->flowinfo;
 329         p->link = u->link;
 330         p->proto = u->proto;
 331 +       p->fmrs = NULL;
 332         memcpy(p->name, u->name, sizeof(u->name));
 333  }
 334
 335 @@ -1633,6 +1791,15 @@ static int ip6_tnl_validate(struct nlatt
 336         return 0;
 337  }
 338
 339 +static const struct nla_policy ip6_tnl_fmr_policy[IFLA_IPTUN_FMR_MAX + 1] = {
 340 +       [IFLA_IPTUN_FMR_IP6_PREFIX] = { .len = sizeof(struct in6_addr) },
 341 +       [IFLA_IPTUN_FMR_IP4_PREFIX] = { .len = sizeof(struct in_addr) },
 342 +       [IFLA_IPTUN_FMR_IP6_PREFIX_LEN] = { .type = NLA_U8 },
 343 +       [IFLA_IPTUN_FMR_IP4_PREFIX_LEN] = { .type = NLA_U8 },
 344 +       [IFLA_IPTUN_FMR_EA_LEN] = { .type = NLA_U8 },
 345 +       [IFLA_IPTUN_FMR_OFFSET] = { .type = NLA_U8 }
 346 +};
 347 +
 348  static void ip6_tnl_netlink_parms(struct nlattr *data[],
 349                                   struct __ip6_tnl_parm *parms)
 350  {
 351 @@ -1666,6 +1833,46 @@ static void ip6_tnl_netlink_parms(struct
 352
 353         if (data[IFLA_IPTUN_PROTO])
 354                 parms->proto = nla_get_u8(data[IFLA_IPTUN_PROTO]);
 355 +
 356 +       if (data[IFLA_IPTUN_FMRS]) {
 357 +               unsigned rem;
 358 +               struct nlattr *fmr;
 359 +               nla_for_each_nested(fmr, data[IFLA_IPTUN_FMRS], rem) {
 360 +                       struct nlattr *fmrd[IFLA_IPTUN_FMR_MAX + 1], *c;
 361 +                       struct __ip6_tnl_fmr *nfmr;
 362 +
 363 +                       nla_parse_nested(fmrd, IFLA_IPTUN_FMR_MAX,
 364 +                               fmr, ip6_tnl_fmr_policy);
 365 +
 366 +                       if (!(nfmr = kzalloc(sizeof(*nfmr), GFP_KERNEL)))
 367 +                               continue;
 368 +
 369 +                       nfmr->offset = 6;
 370 +
 371 +                       if ((c = fmrd[IFLA_IPTUN_FMR_IP6_PREFIX]))
 372 +                               nla_memcpy(&nfmr->ip6_prefix, fmrd[IFLA_IPTUN_FMR_IP6_PREFIX],
 373 +                                       sizeof(nfmr->ip6_prefix));
 374 +
 375 +                       if ((c = fmrd[IFLA_IPTUN_FMR_IP4_PREFIX]))
 376 +                               nla_memcpy(&nfmr->ip4_prefix, fmrd[IFLA_IPTUN_FMR_IP4_PREFIX],
 377 +                                       sizeof(nfmr->ip4_prefix));
 378 +
 379 +                       if ((c = fmrd[IFLA_IPTUN_FMR_IP6_PREFIX_LEN]))
 380 +                               nfmr->ip6_prefix_len = nla_get_u8(c);
 381 +
 382 +                       if ((c = fmrd[IFLA_IPTUN_FMR_IP4_PREFIX_LEN]))
 383 +                               nfmr->ip4_prefix_len = nla_get_u8(c);
 384 +
 385 +                       if ((c = fmrd[IFLA_IPTUN_FMR_EA_LEN]))
 386 +                               nfmr->ea_len = nla_get_u8(c);
 387 +
 388 +                       if ((c = fmrd[IFLA_IPTUN_FMR_OFFSET]))
 389 +                               nfmr->offset = nla_get_u8(c);
 390 +
 391 +                       nfmr->next = parms->fmrs;
 392 +                       parms->fmrs = nfmr;
 393 +               }
 394 +       }
 395  }
 396
 397  static int ip6_tnl_newlink(struct net *src_net, struct net_device *dev,
 398 @@ -1718,6 +1925,12 @@ static void ip6_tnl_dellink(struct net_d
 399
 400  static size_t ip6_tnl_get_size(const struct net_device *dev)
 401  {
 402 +       const struct ip6_tnl *t = netdev_priv(dev);
 403 +       struct __ip6_tnl_fmr *c;
 404 +       int fmrs = 0;
 405 +       for (c = t->parms.fmrs; c; c = c->next)
 406 +               ++fmrs;
 407 +
 408         return
 409                 /* IFLA_IPTUN_LINK */
 410                 nla_total_size(4) +
 411 @@ -1735,6 +1948,24 @@ static size_t ip6_tnl_get_size(const str
 412                 nla_total_size(4) +
 413                 /* IFLA_IPTUN_PROTO */
 414                 nla_total_size(1) +
 415 +               /* IFLA_IPTUN_FMRS */
 416 +               nla_total_size(0) +
 417 +               (
 418 +                       /* nest */
 419 +                       nla_total_size(0) +
 420 +                       /* IFLA_IPTUN_FMR_IP6_PREFIX */
 421 +                       nla_total_size(sizeof(struct in6_addr)) +
 422 +                       /* IFLA_IPTUN_FMR_IP4_PREFIX */
 423 +                       nla_total_size(sizeof(struct in_addr)) +
 424 +                       /* IFLA_IPTUN_FMR_EA_LEN */
 425 +                       nla_total_size(1) +
 426 +                       /* IFLA_IPTUN_FMR_IP6_PREFIX_LEN */
 427 +                       nla_total_size(1) +
 428 +                       /* IFLA_IPTUN_FMR_IP4_PREFIX_LEN */
 429 +                       nla_total_size(1) +
 430 +                       /* IFLA_IPTUN_FMR_OFFSET */
 431 +                       nla_total_size(1)
 432 +               ) * fmrs +
 433                 0;
 434  }
 435
 436 @@ -1742,6 +1973,9 @@ static int ip6_tnl_fill_info(struct sk_b
 437  {
 438         struct ip6_tnl *tunnel = netdev_priv(dev);
 439         struct __ip6_tnl_parm *parm = &tunnel->parms;
 440 +       struct __ip6_tnl_fmr *c;
 441 +       int fmrcnt = 0;
 442 +       struct nlattr *fmrs;
 443
 444         if (nla_put_u32(skb, IFLA_IPTUN_LINK, parm->link) ||
 445             nla_put(skb, IFLA_IPTUN_LOCAL, sizeof(struct in6_addr),
 446 @@ -1752,8 +1986,27 @@ static int ip6_tnl_fill_info(struct sk_b
 447             nla_put_u8(skb, IFLA_IPTUN_ENCAP_LIMIT, parm->encap_limit) ||
 448             nla_put_be32(skb, IFLA_IPTUN_FLOWINFO, parm->flowinfo) ||
 449             nla_put_u32(skb, IFLA_IPTUN_FLAGS, parm->flags) ||
 450 -           nla_put_u8(skb, IFLA_IPTUN_PROTO, parm->proto))
 451 +           nla_put_u8(skb, IFLA_IPTUN_PROTO, parm->proto) ||
 452 +           !(fmrs = nla_nest_start(skb, IFLA_IPTUN_FMRS)))
 453                 goto nla_put_failure;
 454 +
 455 +       for (c = parm->fmrs; c; c = c->next) {
 456 +               struct nlattr *fmr = nla_nest_start(skb, ++fmrcnt);
 457 +               if (!fmr ||
 458 +                       nla_put(skb, IFLA_IPTUN_FMR_IP6_PREFIX,
 459 +                               sizeof(c->ip6_prefix), &c->ip6_prefix) ||
 460 +                       nla_put(skb, IFLA_IPTUN_FMR_IP4_PREFIX,
 461 +                               sizeof(c->ip4_prefix), &c->ip4_prefix) ||
 462 +                       nla_put_u8(skb, IFLA_IPTUN_FMR_IP6_PREFIX_LEN, c->ip6_prefix_len) ||
 463 +                       nla_put_u8(skb, IFLA_IPTUN_FMR_IP4_PREFIX_LEN, c->ip4_prefix_len) ||
 464 +                       nla_put_u8(skb, IFLA_IPTUN_FMR_EA_LEN, c->ea_len) ||
 465 +                       nla_put_u8(skb, IFLA_IPTUN_FMR_OFFSET, c->offset))
 466 +                               goto nla_put_failure;
 467 +
 468 +               nla_nest_end(skb, fmr);
 469 +       }
 470 +       nla_nest_end(skb, fmrs);
 471 +
 472         return 0;
 473
 474  nla_put_failure:
 475 @@ -1769,6 +2022,7 @@ static const struct nla_policy ip6_tnl_p
 476         [IFLA_IPTUN_FLOWINFO]           = { .type = NLA_U32 },
 477         [IFLA_IPTUN_FLAGS]              = { .type = NLA_U32 },
 478         [IFLA_IPTUN_PROTO]              = { .type = NLA_U8 },
 479 +       [IFLA_IPTUN_FMRS]               = { .type = NLA_NESTED },
 480  };
 481
 482  static struct rtnl_link_ops ip6_link_ops __read_mostly = {