net/sched/act_csum.c

   1 /*
   2  * Checksum updating actions
   3  *
   4  * Copyright (c) 2010 Gregoire Baron <baronchon@n7mm.org>
   5  *
   6  * This program is free software; you can redistribute it and/or modify it
   7  * under the terms of the GNU General Public License as published by the Free
   8  * Software Foundation; either version 2 of the License, or (at your option)
   9  * any later version.
  10  *
  11  */
  12
  13 #include <linux/types.h>
  14 #include <linux/init.h>
  15 #include <linux/kernel.h>
  16 #include <linux/module.h>
  17 #include <linux/spinlock.h>
  18
  19 #include <linux/netlink.h>
  20 #include <net/netlink.h>
  21 #include <linux/rtnetlink.h>
  22
  23 #include <linux/skbuff.h>
  24
  25 #include <net/ip.h>
  26 #include <net/ipv6.h>
  27 #include <net/icmp.h>
  28 #include <linux/icmpv6.h>
  29 #include <linux/igmp.h>
  30 #include <net/tcp.h>
  31 #include <net/udp.h>
  32 #include <net/ip6_checksum.h>
  33 #include <net/sctp/checksum.h>
  34
  35 #include <net/act_api.h>
  36
  37 #include <linux/tc_act/tc_csum.h>
  38 #include <net/tc_act/tc_csum.h>
  39
  40 static const struct nla_policy csum_policy[TCA_CSUM_MAX + 1] = {
  41         [TCA_CSUM_PARMS] = { .len = sizeof(struct tc_csum), },
  42 };
  43
  44 static unsigned int csum_net_id;
  45 static struct tc_action_ops act_csum_ops;
  46
  47 static int tcf_csum_init(struct net *net, struct nlattr *nla,
  48                          struct nlattr *est, struct tc_action **a, int ovr,
  49                          int bind, struct netlink_ext_ack *extack)
  50 {
  51         struct tc_action_net *tn = net_generic(net, csum_net_id);
  52         struct tcf_csum_params *params_old, *params_new;
  53         struct nlattr *tb[TCA_CSUM_MAX + 1];
  54         struct tc_csum *parm;
  55         struct tcf_csum *p;
  56         int ret = 0, err;
  57
  58         if (nla == NULL)
  59                 return -EINVAL;
  60
  61         err = nla_parse_nested(tb, TCA_CSUM_MAX, nla, csum_policy, NULL);
  62         if (err < 0)
  63                 return err;
  64
  65         if (tb[TCA_CSUM_PARMS] == NULL)
  66                 return -EINVAL;
  67         parm = nla_data(tb[TCA_CSUM_PARMS]);
  68
  69         if (!tcf_idr_check(tn, parm->index, a, bind)) {
  70                 ret = tcf_idr_create(tn, parm->index, est, a,
  71                                      &act_csum_ops, bind, true);
  72                 if (ret)
  73                         return ret;
  74                 ret = ACT_P_CREATED;
  75         } else {
  76                 if (bind)/* dont override defaults */
  77                         return 0;
  78                 tcf_idr_release(*a, bind);
  79                 if (!ovr)
  80                         return -EEXIST;
  81         }
  82
  83         p = to_tcf_csum(*a);
  84         ASSERT_RTNL();
  85
  86         params_new = kzalloc(sizeof(*params_new), GFP_KERNEL);
  87         if (unlikely(!params_new)) {
  88                 if (ret == ACT_P_CREATED)
  89                         tcf_idr_release(*a, bind);
  90                 return -ENOMEM;
  91         }
  92         params_old = rtnl_dereference(p->params);
  93
  94         params_new->action = parm->action;
  95         params_new->update_flags = parm->update_flags;
  96         rcu_assign_pointer(p->params, params_new);
  97         if (params_old)
  98                 kfree_rcu(params_old, rcu);
  99
 100         if (ret == ACT_P_CREATED)
 101                 tcf_idr_insert(tn, *a);
 102
 103         return ret;
 104 }
 105
 106 /**
 107  * tcf_csum_skb_nextlayer - Get next layer pointer
 108  * @skb: sk_buff to use
 109  * @ihl: previous summed headers length
 110  * @ipl: complete packet length
 111  * @jhl: next header length
 112  *
 113  * Check the expected next layer availability in the specified sk_buff.
 114  * Return the next layer pointer if pass, NULL otherwise.
 115  */
 116 static void *tcf_csum_skb_nextlayer(struct sk_buff *skb,
 117                                     unsigned int ihl, unsigned int ipl,
 118                                     unsigned int jhl)
 119 {
 120         int ntkoff = skb_network_offset(skb);
 121         int hl = ihl + jhl;
 122
 123         if (!pskb_may_pull(skb, ipl + ntkoff) || (ipl < hl) ||
 124             skb_try_make_writable(skb, hl + ntkoff))
 125                 return NULL;
 126         else
 127                 return (void *)(skb_network_header(skb) + ihl);
 128 }
 129
 130 static int tcf_csum_ipv4_icmp(struct sk_buff *skb, unsigned int ihl,
 131                               unsigned int ipl)
 132 {
 133         struct icmphdr *icmph;
 134
 135         icmph = tcf_csum_skb_nextlayer(skb, ihl, ipl, sizeof(*icmph));
 136         if (icmph == NULL)
 137                 return 0;
 138
 139         icmph->checksum = 0;
 140         skb->csum = csum_partial(icmph, ipl - ihl, 0);
 141         icmph->checksum = csum_fold(skb->csum);
 142
 143         skb->ip_summed = CHECKSUM_NONE;
 144
 145         return 1;
 146 }
 147
 148 static int tcf_csum_ipv4_igmp(struct sk_buff *skb,
 149                               unsigned int ihl, unsigned int ipl)
 150 {
 151         struct igmphdr *igmph;
 152
 153         igmph = tcf_csum_skb_nextlayer(skb, ihl, ipl, sizeof(*igmph));
 154         if (igmph == NULL)
 155                 return 0;
 156
 157         igmph->csum = 0;
 158         skb->csum = csum_partial(igmph, ipl - ihl, 0);
 159         igmph->csum = csum_fold(skb->csum);
 160
 161         skb->ip_summed = CHECKSUM_NONE;
 162
 163         return 1;
 164 }
 165
 166 static int tcf_csum_ipv6_icmp(struct sk_buff *skb, unsigned int ihl,
 167                               unsigned int ipl)
 168 {
 169         struct icmp6hdr *icmp6h;
 170         const struct ipv6hdr *ip6h;
 171
 172         icmp6h = tcf_csum_skb_nextlayer(skb, ihl, ipl, sizeof(*icmp6h));
 173         if (icmp6h == NULL)
 174                 return 0;
 175
 176         ip6h = ipv6_hdr(skb);
 177         icmp6h->icmp6_cksum = 0;
 178         skb->csum = csum_partial(icmp6h, ipl - ihl, 0);
 179         icmp6h->icmp6_cksum = csum_ipv6_magic(&ip6h->saddr, &ip6h->daddr,
 180                                               ipl - ihl, IPPROTO_ICMPV6,
 181                                               skb->csum);
 182
 183         skb->ip_summed = CHECKSUM_NONE;
 184
 185         return 1;
 186 }
 187
 188 static int tcf_csum_ipv4_tcp(struct sk_buff *skb, unsigned int ihl,
 189                              unsigned int ipl)
 190 {
 191         struct tcphdr *tcph;
 192         const struct iphdr *iph;
 193
 194         if (skb_is_gso(skb) && skb_shinfo(skb)->gso_type & SKB_GSO_TCPV4)
 195                 return 1;
 196
 197         tcph = tcf_csum_skb_nextlayer(skb, ihl, ipl, sizeof(*tcph));
 198         if (tcph == NULL)
 199                 return 0;
 200
 201         iph = ip_hdr(skb);
 202         tcph->check = 0;
 203         skb->csum = csum_partial(tcph, ipl - ihl, 0);
 204         tcph->check = tcp_v4_check(ipl - ihl,
 205                                    iph->saddr, iph->daddr, skb->csum);
 206
 207         skb->ip_summed = CHECKSUM_NONE;
 208
 209         return 1;
 210 }
 211
 212 static int tcf_csum_ipv6_tcp(struct sk_buff *skb, unsigned int ihl,
 213                              unsigned int ipl)
 214 {
 215         struct tcphdr *tcph;
 216         const struct ipv6hdr *ip6h;
 217
 218         if (skb_is_gso(skb) && skb_shinfo(skb)->gso_type & SKB_GSO_TCPV6)
 219                 return 1;
 220
 221         tcph = tcf_csum_skb_nextlayer(skb, ihl, ipl, sizeof(*tcph));
 222         if (tcph == NULL)
 223                 return 0;
 224
 225         ip6h = ipv6_hdr(skb);
 226         tcph->check = 0;
 227         skb->csum = csum_partial(tcph, ipl - ihl, 0);
 228         tcph->check = csum_ipv6_magic(&ip6h->saddr, &ip6h->daddr,
 229                                       ipl - ihl, IPPROTO_TCP,
 230                                       skb->csum);
 231
 232         skb->ip_summed = CHECKSUM_NONE;
 233
 234         return 1;
 235 }
 236
 237 static int tcf_csum_ipv4_udp(struct sk_buff *skb, unsigned int ihl,
 238                              unsigned int ipl, int udplite)
 239 {
 240         struct udphdr *udph;
 241         const struct iphdr *iph;
 242         u16 ul;
 243
 244         if (skb_is_gso(skb) && skb_shinfo(skb)->gso_type & SKB_GSO_UDP)
 245                 return 1;
 246
 247         /*
 248          * Support both UDP and UDPLITE checksum algorithms, Don't use
 249          * udph->len to get the real length without any protocol check,
 250          * UDPLITE uses udph->len for another thing,
 251          * Use iph->tot_len, or just ipl.
 252          */
 253
 254         udph = tcf_csum_skb_nextlayer(skb, ihl, ipl, sizeof(*udph));
 255         if (udph == NULL)
 256                 return 0;
 257
 258         iph = ip_hdr(skb);
 259         ul = ntohs(udph->len);
 260
 261         if (udplite || udph->check) {
 262
 263                 udph->check = 0;
 264
 265                 if (udplite) {
 266                         if (ul == 0)
 267                                 skb->csum = csum_partial(udph, ipl - ihl, 0);
 268                         else if ((ul >= sizeof(*udph)) && (ul <= ipl - ihl))
 269                                 skb->csum = csum_partial(udph, ul, 0);
 270                         else
 271                                 goto ignore_obscure_skb;
 272                 } else {
 273                         if (ul != ipl - ihl)
 274                                 goto ignore_obscure_skb;
 275
 276                         skb->csum = csum_partial(udph, ul, 0);
 277                 }
 278
 279                 udph->check = csum_tcpudp_magic(iph->saddr, iph->daddr,
 280                                                 ul, iph->protocol,
 281                                                 skb->csum);
 282
 283                 if (!udph->check)
 284                         udph->check = CSUM_MANGLED_0;
 285         }
 286
 287         skb->ip_summed = CHECKSUM_NONE;
 288
 289 ignore_obscure_skb:
 290         return 1;
 291 }
 292
 293 static int tcf_csum_ipv6_udp(struct sk_buff *skb, unsigned int ihl,
 294                              unsigned int ipl, int udplite)
 295 {
 296         struct udphdr *udph;
 297         const struct ipv6hdr *ip6h;
 298         u16 ul;
 299
 300         if (skb_is_gso(skb) && skb_shinfo(skb)->gso_type & SKB_GSO_UDP)
 301                 return 1;
 302
 303         /*
 304          * Support both UDP and UDPLITE checksum algorithms, Don't use
 305          * udph->len to get the real length without any protocol check,
 306          * UDPLITE uses udph->len for another thing,
 307          * Use ip6h->payload_len + sizeof(*ip6h) ... , or just ipl.
 308          */
 309
 310         udph = tcf_csum_skb_nextlayer(skb, ihl, ipl, sizeof(*udph));
 311         if (udph == NULL)
 312                 return 0;
 313
 314         ip6h = ipv6_hdr(skb);
 315         ul = ntohs(udph->len);
 316
 317         udph->check = 0;
 318
 319         if (udplite) {
 320                 if (ul == 0)
 321                         skb->csum = csum_partial(udph, ipl - ihl, 0);
 322
 323                 else if ((ul >= sizeof(*udph)) && (ul <= ipl - ihl))
 324                         skb->csum = csum_partial(udph, ul, 0);
 325
 326                 else
 327                         goto ignore_obscure_skb;
 328         } else {
 329                 if (ul != ipl - ihl)
 330                         goto ignore_obscure_skb;
 331
 332                 skb->csum = csum_partial(udph, ul, 0);
 333         }
 334
 335         udph->check = csum_ipv6_magic(&ip6h->saddr, &ip6h->daddr, ul,
 336                                       udplite ? IPPROTO_UDPLITE : IPPROTO_UDP,
 337                                       skb->csum);
 338
 339         if (!udph->check)
 340                 udph->check = CSUM_MANGLED_0;
 341
 342         skb->ip_summed = CHECKSUM_NONE;
 343
 344 ignore_obscure_skb:
 345         return 1;
 346 }
 347
 348 static int tcf_csum_sctp(struct sk_buff *skb, unsigned int ihl,
 349                          unsigned int ipl)
 350 {
 351         struct sctphdr *sctph;
 352
 353         if (skb_is_gso(skb) && skb_is_gso_sctp(skb))
 354                 return 1;
 355
 356         sctph = tcf_csum_skb_nextlayer(skb, ihl, ipl, sizeof(*sctph));
 357         if (!sctph)
 358                 return 0;
 359
 360         sctph->checksum = sctp_compute_cksum(skb,
 361                                              skb_network_offset(skb) + ihl);
 362         skb->ip_summed = CHECKSUM_NONE;
 363         skb->csum_not_inet = 0;
 364
 365         return 1;
 366 }
 367
 368 static int tcf_csum_ipv4(struct sk_buff *skb, u32 update_flags)
 369 {
 370         const struct iphdr *iph;
 371         int ntkoff;
 372
 373         ntkoff = skb_network_offset(skb);
 374
 375         if (!pskb_may_pull(skb, sizeof(*iph) + ntkoff))
 376                 goto fail;
 377
 378         iph = ip_hdr(skb);
 379
 380         switch (iph->frag_off & htons(IP_OFFSET) ? 0 : iph->protocol) {
 381         case IPPROTO_ICMP:
 382                 if (update_flags & TCA_CSUM_UPDATE_FLAG_ICMP)
 383                         if (!tcf_csum_ipv4_icmp(skb, iph->ihl * 4,
 384                                                 ntohs(iph->tot_len)))
 385                                 goto fail;
 386                 break;
 387         case IPPROTO_IGMP:
 388                 if (update_flags & TCA_CSUM_UPDATE_FLAG_IGMP)
 389                         if (!tcf_csum_ipv4_igmp(skb, iph->ihl * 4,
 390                                                 ntohs(iph->tot_len)))
 391                                 goto fail;
 392                 break;
 393         case IPPROTO_TCP:
 394                 if (update_flags & TCA_CSUM_UPDATE_FLAG_TCP)
 395                         if (!tcf_csum_ipv4_tcp(skb, iph->ihl * 4,
 396                                                ntohs(iph->tot_len)))
 397                                 goto fail;
 398                 break;
 399         case IPPROTO_UDP:
 400                 if (update_flags & TCA_CSUM_UPDATE_FLAG_UDP)
 401                         if (!tcf_csum_ipv4_udp(skb, iph->ihl * 4,
 402                                                ntohs(iph->tot_len), 0))
 403                                 goto fail;
 404                 break;
 405         case IPPROTO_UDPLITE:
 406                 if (update_flags & TCA_CSUM_UPDATE_FLAG_UDPLITE)
 407                         if (!tcf_csum_ipv4_udp(skb, iph->ihl * 4,
 408                                                ntohs(iph->tot_len), 1))
 409                                 goto fail;
 410                 break;
 411         case IPPROTO_SCTP:
 412                 if ((update_flags & TCA_CSUM_UPDATE_FLAG_SCTP) &&
 413                     !tcf_csum_sctp(skb, iph->ihl * 4, ntohs(iph->tot_len)))
 414                         goto fail;
 415                 break;
 416         }
 417
 418         if (update_flags & TCA_CSUM_UPDATE_FLAG_IPV4HDR) {
 419                 if (skb_try_make_writable(skb, sizeof(*iph) + ntkoff))
 420                         goto fail;
 421
 422                 ip_send_check(ip_hdr(skb));
 423         }
 424
 425         return 1;
 426
 427 fail:
 428         return 0;
 429 }
 430
 431 static int tcf_csum_ipv6_hopopts(struct ipv6_opt_hdr *ip6xh, unsigned int ixhl,
 432                                  unsigned int *pl)
 433 {
 434         int off, len, optlen;
 435         unsigned char *xh = (void *)ip6xh;
 436
 437         off = sizeof(*ip6xh);
 438         len = ixhl - off;
 439
 440         while (len > 1) {
 441                 switch (xh[off]) {
 442                 case IPV6_TLV_PAD1:
 443                         optlen = 1;
 444                         break;
 445                 case IPV6_TLV_JUMBO:
 446                         optlen = xh[off + 1] + 2;
 447                         if (optlen != 6 || len < 6 || (off & 3) != 2)
 448                                 /* wrong jumbo option length/alignment */
 449                                 return 0;
 450                         *pl = ntohl(*(__be32 *)(xh + off + 2));
 451                         goto done;
 452                 default:
 453                         optlen = xh[off + 1] + 2;
 454                         if (optlen > len)
 455                                 /* ignore obscure options */
 456                                 goto done;
 457                         break;
 458                 }
 459                 off += optlen;
 460                 len -= optlen;
 461         }
 462
 463 done:
 464         return 1;
 465 }
 466
 467 static int tcf_csum_ipv6(struct sk_buff *skb, u32 update_flags)
 468 {
 469         struct ipv6hdr *ip6h;
 470         struct ipv6_opt_hdr *ip6xh;
 471         unsigned int hl, ixhl;
 472         unsigned int pl;
 473         int ntkoff;
 474         u8 nexthdr;
 475
 476         ntkoff = skb_network_offset(skb);
 477
 478         hl = sizeof(*ip6h);
 479
 480         if (!pskb_may_pull(skb, hl + ntkoff))
 481                 goto fail;
 482
 483         ip6h = ipv6_hdr(skb);
 484
 485         pl = ntohs(ip6h->payload_len);
 486         nexthdr = ip6h->nexthdr;
 487
 488         do {
 489                 switch (nexthdr) {
 490                 case NEXTHDR_FRAGMENT:
 491                         goto ignore_skb;
 492                 case NEXTHDR_ROUTING:
 493                 case NEXTHDR_HOP:
 494                 case NEXTHDR_DEST:
 495                         if (!pskb_may_pull(skb, hl + sizeof(*ip6xh) + ntkoff))
 496                                 goto fail;
 497                         ip6xh = (void *)(skb_network_header(skb) + hl);
 498                         ixhl = ipv6_optlen(ip6xh);
 499                         if (!pskb_may_pull(skb, hl + ixhl + ntkoff))
 500                                 goto fail;
 501                         ip6xh = (void *)(skb_network_header(skb) + hl);
 502                         if ((nexthdr == NEXTHDR_HOP) &&
 503                             !(tcf_csum_ipv6_hopopts(ip6xh, ixhl, &pl)))
 504                                 goto fail;
 505                         nexthdr = ip6xh->nexthdr;
 506                         hl += ixhl;
 507                         break;
 508                 case IPPROTO_ICMPV6:
 509                         if (update_flags & TCA_CSUM_UPDATE_FLAG_ICMP)
 510                                 if (!tcf_csum_ipv6_icmp(skb,
 511                                                         hl, pl + sizeof(*ip6h)))
 512                                         goto fail;
 513                         goto done;
 514                 case IPPROTO_TCP:
 515                         if (update_flags & TCA_CSUM_UPDATE_FLAG_TCP)
 516                                 if (!tcf_csum_ipv6_tcp(skb,
 517                                                        hl, pl + sizeof(*ip6h)))
 518                                         goto fail;
 519                         goto done;
 520                 case IPPROTO_UDP:
 521                         if (update_flags & TCA_CSUM_UPDATE_FLAG_UDP)
 522                                 if (!tcf_csum_ipv6_udp(skb, hl,
 523                                                        pl + sizeof(*ip6h), 0))
 524                                         goto fail;
 525                         goto done;
 526                 case IPPROTO_UDPLITE:
 527                         if (update_flags & TCA_CSUM_UPDATE_FLAG_UDPLITE)
 528                                 if (!tcf_csum_ipv6_udp(skb, hl,
 529                                                        pl + sizeof(*ip6h), 1))
 530                                         goto fail;
 531                         goto done;
 532                 case IPPROTO_SCTP:
 533                         if ((update_flags & TCA_CSUM_UPDATE_FLAG_SCTP) &&
 534                             !tcf_csum_sctp(skb, hl, pl + sizeof(*ip6h)))
 535                                 goto fail;
 536                         goto done;
 537                 default:
 538                         goto ignore_skb;
 539                 }
 540         } while (pskb_may_pull(skb, hl + 1 + ntkoff));
 541
 542 done:
 543 ignore_skb:
 544         return 1;
 545
 546 fail:
 547         return 0;
 548 }
 549
 550 static int tcf_csum(struct sk_buff *skb, const struct tc_action *a,
 551                     struct tcf_result *res)
 552 {
 553         struct tcf_csum *p = to_tcf_csum(a);
 554         struct tcf_csum_params *params;
 555         u32 update_flags;
 556         int action;
 557
 558         rcu_read_lock();
 559         params = rcu_dereference(p->params);
 560
 561         tcf_lastuse_update(&p->tcf_tm);
 562         bstats_cpu_update(this_cpu_ptr(p->common.cpu_bstats), skb);
 563
 564         action = params->action;
 565         if (unlikely(action == TC_ACT_SHOT))
 566                 goto drop_stats;
 567
 568         update_flags = params->update_flags;
 569         switch (tc_skb_protocol(skb)) {
 570         case cpu_to_be16(ETH_P_IP):
 571                 if (!tcf_csum_ipv4(skb, update_flags))
 572                         goto drop;
 573                 break;
 574         case cpu_to_be16(ETH_P_IPV6):
 575                 if (!tcf_csum_ipv6(skb, update_flags))
 576                         goto drop;
 577                 break;
 578         }
 579
 580 unlock:
 581         rcu_read_unlock();
 582         return action;
 583
 584 drop:
 585         action = TC_ACT_SHOT;
 586
 587 drop_stats:
 588         qstats_drop_inc(this_cpu_ptr(p->common.cpu_qstats));
 589         goto unlock;
 590 }
 591
 592 static int tcf_csum_dump(struct sk_buff *skb, struct tc_action *a, int bind,
 593                          int ref)
 594 {
 595         unsigned char *b = skb_tail_pointer(skb);
 596         struct tcf_csum *p = to_tcf_csum(a);
 597         struct tcf_csum_params *params;
 598         struct tc_csum opt = {
 599                 .index   = p->tcf_index,
 600                 .refcnt  = p->tcf_refcnt - ref,
 601                 .bindcnt = p->tcf_bindcnt - bind,
 602         };
 603         struct tcf_t t;
 604
 605         params = rtnl_dereference(p->params);
 606         opt.action = params->action;
 607         opt.update_flags = params->update_flags;
 608
 609         if (nla_put(skb, TCA_CSUM_PARMS, sizeof(opt), &opt))
 610                 goto nla_put_failure;
 611
 612         tcf_tm_dump(&t, &p->tcf_tm);
 613         if (nla_put_64bit(skb, TCA_CSUM_TM, sizeof(t), &t, TCA_CSUM_PAD))
 614                 goto nla_put_failure;
 615
 616         return skb->len;
 617
 618 nla_put_failure:
 619         nlmsg_trim(skb, b);
 620         return -1;
 621 }
 622
 623 static void tcf_csum_cleanup(struct tc_action *a)
 624 {
 625         struct tcf_csum *p = to_tcf_csum(a);
 626         struct tcf_csum_params *params;
 627
 628         params = rcu_dereference_protected(p->params, 1);
 629         if (params)
 630                 kfree_rcu(params, rcu);
 631 }
 632
 633 static int tcf_csum_walker(struct net *net, struct sk_buff *skb,
 634                            struct netlink_callback *cb, int type,
 635                            const struct tc_action_ops *ops,
 636                            struct netlink_ext_ack *extack)
 637 {
 638         struct tc_action_net *tn = net_generic(net, csum_net_id);
 639
 640         return tcf_generic_walker(tn, skb, cb, type, ops, extack);
 641 }
 642
 643 static int tcf_csum_search(struct net *net, struct tc_action **a, u32 index,
 644                            struct netlink_ext_ack *extack)
 645 {
 646         struct tc_action_net *tn = net_generic(net, csum_net_id);
 647
 648         return tcf_idr_search(tn, a, index);
 649 }
 650
 651 static size_t tcf_csum_get_fill_size(const struct tc_action *act)
 652 {
 653         return nla_total_size(sizeof(struct tc_csum));
 654 }
 655
 656 static struct tc_action_ops act_csum_ops = {
 657         .kind           = "csum",
 658         .type           = TCA_ACT_CSUM,
 659         .owner          = THIS_MODULE,
 660         .act            = tcf_csum,
 661         .dump           = tcf_csum_dump,
 662         .init           = tcf_csum_init,
 663         .cleanup        = tcf_csum_cleanup,
 664         .walk           = tcf_csum_walker,
 665         .lookup         = tcf_csum_search,
 666         .get_fill_size  = tcf_csum_get_fill_size,
 667         .size           = sizeof(struct tcf_csum),
 668 };
 669
 670 static __net_init int csum_init_net(struct net *net)
 671 {
 672         struct tc_action_net *tn = net_generic(net, csum_net_id);
 673
 674         return tc_action_net_init(tn, &act_csum_ops);
 675 }
 676
 677 static void __net_exit csum_exit_net(struct list_head *net_list)
 678 {
 679         tc_action_net_exit(net_list, csum_net_id);
 680 }
 681
 682 static struct pernet_operations csum_net_ops = {
 683         .init = csum_init_net,
 684         .exit_batch = csum_exit_net,
 685         .id   = &csum_net_id,
 686         .size = sizeof(struct tc_action_net),
 687 };
 688
 689 MODULE_DESCRIPTION("Checksum updating actions");
 690 MODULE_LICENSE("GPL");
 691
 692 static int __init csum_init_module(void)
 693 {
 694         return tcf_register_action(&act_csum_ops, &csum_net_ops);
 695 }
 696
 697 static void __exit csum_cleanup_module(void)
 698 {
 699         tcf_unregister_action(&act_csum_ops, &csum_net_ops);
 700 }
 701
 702 module_init(csum_init_module);
 703 module_exit(csum_cleanup_module);