1 /* 2 * net/sched/ife.c Inter-FE action based on ForCES WG InterFE LFB 3 * 4 * Refer to: 5 * draft-ietf-forces-interfelfb-03 6 * and 7 * netdev01 paper: 8 * "Distributing Linux Traffic Control Classifier-Action 9 * Subsystem" 10 * Authors: Jamal Hadi Salim and Damascene M. Joachimpillai 11 * 12 * This program is free software; you can redistribute it and/or 13 * modify it under the terms of the GNU General Public License 14 * as published by the Free Software Foundation; either version 15 * 2 of the License, or (at your option) any later version. 16 * 17 * copyright Jamal Hadi Salim (2015) 18 * 19 */ 20 21 #include <linux/types.h> 22 #include <linux/kernel.h> 23 #include <linux/string.h> 24 #include <linux/errno.h> 25 #include <linux/skbuff.h> 26 #include <linux/rtnetlink.h> 27 #include <linux/module.h> 28 #include <linux/init.h> 29 #include <net/net_namespace.h> 30 #include <net/netlink.h> 31 #include <net/pkt_sched.h> 32 #include <uapi/linux/tc_act/tc_ife.h> 33 #include <net/tc_act/tc_ife.h> 34 #include <linux/etherdevice.h> 35 36 #define IFE_TAB_MASK 15 37 38 static int ife_net_id; 39 static int max_metacnt = IFE_META_MAX + 1; 40 41 static const struct nla_policy ife_policy[TCA_IFE_MAX + 1] = { 42 [TCA_IFE_PARMS] = { .len = sizeof(struct tc_ife)}, 43 [TCA_IFE_DMAC] = { .len = ETH_ALEN}, 44 [TCA_IFE_SMAC] = { .len = ETH_ALEN}, 45 [TCA_IFE_TYPE] = { .type = NLA_U16}, 46 }; 47 48 /* Caller takes care of presenting data in network order 49 */ 50 int ife_tlv_meta_encode(void *skbdata, u16 attrtype, u16 dlen, const void *dval) 51 { 52 u32 *tlv = (u32 *)(skbdata); 53 u16 totlen = nla_total_size(dlen); /*alignment + hdr */ 54 char *dptr = (char *)tlv + NLA_HDRLEN; 55 u32 htlv = attrtype << 16 | totlen; 56 57 *tlv = htonl(htlv); 58 memset(dptr, 0, totlen - NLA_HDRLEN); 59 memcpy(dptr, dval, dlen); 60 61 return totlen; 62 } 63 EXPORT_SYMBOL_GPL(ife_tlv_meta_encode); 64 65 int ife_get_meta_u32(struct sk_buff *skb, struct tcf_meta_info *mi) 66 { 67 if (mi->metaval) 68 return nla_put_u32(skb, mi->metaid, *(u32 *)mi->metaval); 69 else 70 return nla_put(skb, mi->metaid, 0, NULL); 71 } 72 EXPORT_SYMBOL_GPL(ife_get_meta_u32); 73 74 int ife_check_meta_u32(u32 metaval, struct tcf_meta_info *mi) 75 { 76 if (metaval || mi->metaval) 77 return 8; /* T+L+V == 2+2+4 */ 78 79 return 0; 80 } 81 EXPORT_SYMBOL_GPL(ife_check_meta_u32); 82 83 int ife_encode_meta_u32(u32 metaval, void *skbdata, struct tcf_meta_info *mi) 84 { 85 u32 edata = metaval; 86 87 if (mi->metaval) 88 edata = *(u32 *)mi->metaval; 89 else if (metaval) 90 edata = metaval; 91 92 if (!edata) /* will not encode */ 93 return 0; 94 95 edata = htonl(edata); 96 return ife_tlv_meta_encode(skbdata, mi->metaid, 4, &edata); 97 } 98 EXPORT_SYMBOL_GPL(ife_encode_meta_u32); 99 100 int ife_get_meta_u16(struct sk_buff *skb, struct tcf_meta_info *mi) 101 { 102 if (mi->metaval) 103 return nla_put_u16(skb, mi->metaid, *(u16 *)mi->metaval); 104 else 105 return nla_put(skb, mi->metaid, 0, NULL); 106 } 107 EXPORT_SYMBOL_GPL(ife_get_meta_u16); 108 109 int ife_alloc_meta_u32(struct tcf_meta_info *mi, void *metaval) 110 { 111 mi->metaval = kmemdup(metaval, sizeof(u32), GFP_KERNEL); 112 if (!mi->metaval) 113 return -ENOMEM; 114 115 return 0; 116 } 117 EXPORT_SYMBOL_GPL(ife_alloc_meta_u32); 118 119 int ife_alloc_meta_u16(struct tcf_meta_info *mi, void *metaval) 120 { 121 mi->metaval = kmemdup(metaval, sizeof(u16), GFP_KERNEL); 122 if (!mi->metaval) 123 return -ENOMEM; 124 125 return 0; 126 } 127 EXPORT_SYMBOL_GPL(ife_alloc_meta_u16); 128 129 void ife_release_meta_gen(struct tcf_meta_info *mi) 130 { 131 kfree(mi->metaval); 132 } 133 EXPORT_SYMBOL_GPL(ife_release_meta_gen); 134 135 int ife_validate_meta_u32(void *val, int len) 136 { 137 if (len == 4) 138 return 0; 139 140 return -EINVAL; 141 } 142 EXPORT_SYMBOL_GPL(ife_validate_meta_u32); 143 144 int ife_validate_meta_u16(void *val, int len) 145 { 146 /* length will include padding */ 147 if (len == NLA_ALIGN(2)) 148 return 0; 149 150 return -EINVAL; 151 } 152 EXPORT_SYMBOL_GPL(ife_validate_meta_u16); 153 154 static LIST_HEAD(ifeoplist); 155 static DEFINE_RWLOCK(ife_mod_lock); 156 157 static struct tcf_meta_ops *find_ife_oplist(u16 metaid) 158 { 159 struct tcf_meta_ops *o; 160 161 read_lock(&ife_mod_lock); 162 list_for_each_entry(o, &ifeoplist, list) { 163 if (o->metaid == metaid) { 164 if (!try_module_get(o->owner)) 165 o = NULL; 166 read_unlock(&ife_mod_lock); 167 return o; 168 } 169 } 170 read_unlock(&ife_mod_lock); 171 172 return NULL; 173 } 174 175 int register_ife_op(struct tcf_meta_ops *mops) 176 { 177 struct tcf_meta_ops *m; 178 179 if (!mops->metaid || !mops->metatype || !mops->name || 180 !mops->check_presence || !mops->encode || !mops->decode || 181 !mops->get || !mops->alloc) 182 return -EINVAL; 183 184 write_lock(&ife_mod_lock); 185 186 list_for_each_entry(m, &ifeoplist, list) { 187 if (m->metaid == mops->metaid || 188 (strcmp(mops->name, m->name) == 0)) { 189 write_unlock(&ife_mod_lock); 190 return -EEXIST; 191 } 192 } 193 194 if (!mops->release) 195 mops->release = ife_release_meta_gen; 196 197 list_add_tail(&mops->list, &ifeoplist); 198 write_unlock(&ife_mod_lock); 199 return 0; 200 } 201 EXPORT_SYMBOL_GPL(unregister_ife_op); 202 203 int unregister_ife_op(struct tcf_meta_ops *mops) 204 { 205 struct tcf_meta_ops *m; 206 int err = -ENOENT; 207 208 write_lock(&ife_mod_lock); 209 list_for_each_entry(m, &ifeoplist, list) { 210 if (m->metaid == mops->metaid) { 211 list_del(&mops->list); 212 err = 0; 213 break; 214 } 215 } 216 write_unlock(&ife_mod_lock); 217 218 return err; 219 } 220 EXPORT_SYMBOL_GPL(register_ife_op); 221 222 static int ife_validate_metatype(struct tcf_meta_ops *ops, void *val, int len) 223 { 224 int ret = 0; 225 /* XXX: unfortunately cant use nla_policy at this point 226 * because a length of 0 is valid in the case of 227 * "allow". "use" semantics do enforce for proper 228 * length and i couldve use nla_policy but it makes it hard 229 * to use it just for that.. 230 */ 231 if (ops->validate) 232 return ops->validate(val, len); 233 234 if (ops->metatype == NLA_U32) 235 ret = ife_validate_meta_u32(val, len); 236 else if (ops->metatype == NLA_U16) 237 ret = ife_validate_meta_u16(val, len); 238 239 return ret; 240 } 241 242 /* called when adding new meta information 243 * under ife->tcf_lock 244 */ 245 static int load_metaops_and_vet(struct tcf_ife_info *ife, u32 metaid, 246 void *val, int len) 247 { 248 struct tcf_meta_ops *ops = find_ife_oplist(metaid); 249 int ret = 0; 250 251 if (!ops) { 252 ret = -ENOENT; 253 #ifdef CONFIG_MODULES 254 spin_unlock_bh(&ife->tcf_lock); 255 rtnl_unlock(); 256 request_module("ifemeta%u", metaid); 257 rtnl_lock(); 258 spin_lock_bh(&ife->tcf_lock); 259 ops = find_ife_oplist(metaid); 260 #endif 261 } 262 263 if (ops) { 264 ret = 0; 265 if (len) 266 ret = ife_validate_metatype(ops, val, len); 267 268 module_put(ops->owner); 269 } 270 271 return ret; 272 } 273 274 /* called when adding new meta information 275 * under ife->tcf_lock 276 */ 277 static int add_metainfo(struct tcf_ife_info *ife, u32 metaid, void *metaval, 278 int len) 279 { 280 struct tcf_meta_info *mi = NULL; 281 struct tcf_meta_ops *ops = find_ife_oplist(metaid); 282 int ret = 0; 283 284 if (!ops) 285 return -ENOENT; 286 287 mi = kzalloc(sizeof(*mi), GFP_KERNEL); 288 if (!mi) { 289 /*put back what find_ife_oplist took */ 290 module_put(ops->owner); 291 return -ENOMEM; 292 } 293 294 mi->metaid = metaid; 295 mi->ops = ops; 296 if (len > 0) { 297 ret = ops->alloc(mi, metaval); 298 if (ret != 0) { 299 kfree(mi); 300 module_put(ops->owner); 301 return ret; 302 } 303 } 304 305 list_add_tail(&mi->metalist, &ife->metalist); 306 307 return ret; 308 } 309 310 static int use_all_metadata(struct tcf_ife_info *ife) 311 { 312 struct tcf_meta_ops *o; 313 int rc = 0; 314 int installed = 0; 315 316 list_for_each_entry(o, &ifeoplist, list) { 317 rc = add_metainfo(ife, o->metaid, NULL, 0); 318 if (rc == 0) 319 installed += 1; 320 } 321 322 if (installed) 323 return 0; 324 else 325 return -EINVAL; 326 } 327 328 static int dump_metalist(struct sk_buff *skb, struct tcf_ife_info *ife) 329 { 330 struct tcf_meta_info *e; 331 struct nlattr *nest; 332 unsigned char *b = skb_tail_pointer(skb); 333 int total_encoded = 0; 334 335 /*can only happen on decode */ 336 if (list_empty(&ife->metalist)) 337 return 0; 338 339 nest = nla_nest_start(skb, TCA_IFE_METALST); 340 if (!nest) 341 goto out_nlmsg_trim; 342 343 list_for_each_entry(e, &ife->metalist, metalist) { 344 if (!e->ops->get(skb, e)) 345 total_encoded += 1; 346 } 347 348 if (!total_encoded) 349 goto out_nlmsg_trim; 350 351 nla_nest_end(skb, nest); 352 353 return 0; 354 355 out_nlmsg_trim: 356 nlmsg_trim(skb, b); 357 return -1; 358 } 359 360 /* under ife->tcf_lock */ 361 static void _tcf_ife_cleanup(struct tc_action *a, int bind) 362 { 363 struct tcf_ife_info *ife = a->priv; 364 struct tcf_meta_info *e, *n; 365 366 list_for_each_entry_safe(e, n, &ife->metalist, metalist) { 367 module_put(e->ops->owner); 368 list_del(&e->metalist); 369 if (e->metaval) { 370 if (e->ops->release) 371 e->ops->release(e); 372 else 373 kfree(e->metaval); 374 } 375 kfree(e); 376 } 377 } 378 379 static void tcf_ife_cleanup(struct tc_action *a, int bind) 380 { 381 struct tcf_ife_info *ife = a->priv; 382 383 spin_lock_bh(&ife->tcf_lock); 384 _tcf_ife_cleanup(a, bind); 385 spin_unlock_bh(&ife->tcf_lock); 386 } 387 388 /* under ife->tcf_lock */ 389 static int populate_metalist(struct tcf_ife_info *ife, struct nlattr **tb) 390 { 391 int len = 0; 392 int rc = 0; 393 int i = 0; 394 void *val; 395 396 for (i = 1; i < max_metacnt; i++) { 397 if (tb[i]) { 398 val = nla_data(tb[i]); 399 len = nla_len(tb[i]); 400 401 rc = load_metaops_and_vet(ife, i, val, len); 402 if (rc != 0) 403 return rc; 404 405 rc = add_metainfo(ife, i, val, len); 406 if (rc) 407 return rc; 408 } 409 } 410 411 return rc; 412 } 413 414 static int tcf_ife_init(struct net *net, struct nlattr *nla, 415 struct nlattr *est, struct tc_action *a, 416 int ovr, int bind) 417 { 418 struct tc_action_net *tn = net_generic(net, ife_net_id); 419 struct nlattr *tb[TCA_IFE_MAX + 1]; 420 struct nlattr *tb2[IFE_META_MAX + 1]; 421 struct tcf_ife_info *ife; 422 struct tc_ife *parm; 423 u16 ife_type = 0; 424 u8 *daddr = NULL; 425 u8 *saddr = NULL; 426 int ret = 0; 427 int err; 428 429 err = nla_parse_nested(tb, TCA_IFE_MAX, nla, ife_policy); 430 if (err < 0) 431 return err; 432 433 if (!tb[TCA_IFE_PARMS]) 434 return -EINVAL; 435 436 parm = nla_data(tb[TCA_IFE_PARMS]); 437 438 if (parm->flags & IFE_ENCODE) { 439 /* Until we get issued the ethertype, we cant have 440 * a default.. 441 **/ 442 if (!tb[TCA_IFE_TYPE]) { 443 pr_info("You MUST pass etherype for encoding\n"); 444 return -EINVAL; 445 } 446 } 447 448 if (!tcf_hash_check(tn, parm->index, a, bind)) { 449 ret = tcf_hash_create(tn, parm->index, est, a, sizeof(*ife), 450 bind, false); 451 if (ret) 452 return ret; 453 ret = ACT_P_CREATED; 454 } else { 455 if (bind) /* dont override defaults */ 456 return 0; 457 tcf_hash_release(a, bind); 458 if (!ovr) 459 return -EEXIST; 460 } 461 462 ife = to_ife(a); 463 ife->flags = parm->flags; 464 465 if (parm->flags & IFE_ENCODE) { 466 ife_type = nla_get_u16(tb[TCA_IFE_TYPE]); 467 if (tb[TCA_IFE_DMAC]) 468 daddr = nla_data(tb[TCA_IFE_DMAC]); 469 if (tb[TCA_IFE_SMAC]) 470 saddr = nla_data(tb[TCA_IFE_SMAC]); 471 } 472 473 spin_lock_bh(&ife->tcf_lock); 474 ife->tcf_action = parm->action; 475 476 if (parm->flags & IFE_ENCODE) { 477 if (daddr) 478 ether_addr_copy(ife->eth_dst, daddr); 479 else 480 eth_zero_addr(ife->eth_dst); 481 482 if (saddr) 483 ether_addr_copy(ife->eth_src, saddr); 484 else 485 eth_zero_addr(ife->eth_src); 486 487 ife->eth_type = ife_type; 488 } 489 490 if (ret == ACT_P_CREATED) 491 INIT_LIST_HEAD(&ife->metalist); 492 493 if (tb[TCA_IFE_METALST]) { 494 err = nla_parse_nested(tb2, IFE_META_MAX, tb[TCA_IFE_METALST], 495 NULL); 496 if (err) { 497 metadata_parse_err: 498 if (ret == ACT_P_CREATED) 499 _tcf_ife_cleanup(a, bind); 500 501 spin_unlock_bh(&ife->tcf_lock); 502 return err; 503 } 504 505 err = populate_metalist(ife, tb2); 506 if (err) 507 goto metadata_parse_err; 508 509 } else { 510 /* if no passed metadata allow list or passed allow-all 511 * then here we process by adding as many supported metadatum 512 * as we can. You better have at least one else we are 513 * going to bail out 514 */ 515 err = use_all_metadata(ife); 516 if (err) { 517 if (ret == ACT_P_CREATED) 518 _tcf_ife_cleanup(a, bind); 519 520 spin_unlock_bh(&ife->tcf_lock); 521 return err; 522 } 523 } 524 525 spin_unlock_bh(&ife->tcf_lock); 526 527 if (ret == ACT_P_CREATED) 528 tcf_hash_insert(tn, a); 529 530 return ret; 531 } 532 533 static int tcf_ife_dump(struct sk_buff *skb, struct tc_action *a, int bind, 534 int ref) 535 { 536 unsigned char *b = skb_tail_pointer(skb); 537 struct tcf_ife_info *ife = a->priv; 538 struct tc_ife opt = { 539 .index = ife->tcf_index, 540 .refcnt = ife->tcf_refcnt - ref, 541 .bindcnt = ife->tcf_bindcnt - bind, 542 .action = ife->tcf_action, 543 .flags = ife->flags, 544 }; 545 struct tcf_t t; 546 547 if (nla_put(skb, TCA_IFE_PARMS, sizeof(opt), &opt)) 548 goto nla_put_failure; 549 550 t.install = jiffies_to_clock_t(jiffies - ife->tcf_tm.install); 551 t.lastuse = jiffies_to_clock_t(jiffies - ife->tcf_tm.lastuse); 552 t.expires = jiffies_to_clock_t(ife->tcf_tm.expires); 553 if (nla_put_64bit(skb, TCA_IFE_TM, sizeof(t), &t, TCA_IFE_PAD)) 554 goto nla_put_failure; 555 556 if (!is_zero_ether_addr(ife->eth_dst)) { 557 if (nla_put(skb, TCA_IFE_DMAC, ETH_ALEN, ife->eth_dst)) 558 goto nla_put_failure; 559 } 560 561 if (!is_zero_ether_addr(ife->eth_src)) { 562 if (nla_put(skb, TCA_IFE_SMAC, ETH_ALEN, ife->eth_src)) 563 goto nla_put_failure; 564 } 565 566 if (nla_put(skb, TCA_IFE_TYPE, 2, &ife->eth_type)) 567 goto nla_put_failure; 568 569 if (dump_metalist(skb, ife)) { 570 /*ignore failure to dump metalist */ 571 pr_info("Failed to dump metalist\n"); 572 } 573 574 return skb->len; 575 576 nla_put_failure: 577 nlmsg_trim(skb, b); 578 return -1; 579 } 580 581 int find_decode_metaid(struct sk_buff *skb, struct tcf_ife_info *ife, 582 u16 metaid, u16 mlen, void *mdata) 583 { 584 struct tcf_meta_info *e; 585 586 /* XXX: use hash to speed up */ 587 list_for_each_entry(e, &ife->metalist, metalist) { 588 if (metaid == e->metaid) { 589 if (e->ops) { 590 /* We check for decode presence already */ 591 return e->ops->decode(skb, mdata, mlen); 592 } 593 } 594 } 595 596 return 0; 597 } 598 599 struct ifeheadr { 600 __be16 metalen; 601 u8 tlv_data[]; 602 }; 603 604 struct meta_tlvhdr { 605 __be16 type; 606 __be16 len; 607 }; 608 609 static int tcf_ife_decode(struct sk_buff *skb, const struct tc_action *a, 610 struct tcf_result *res) 611 { 612 struct tcf_ife_info *ife = a->priv; 613 int action = ife->tcf_action; 614 struct ifeheadr *ifehdr = (struct ifeheadr *)skb->data; 615 u16 ifehdrln = ifehdr->metalen; 616 struct meta_tlvhdr *tlv = (struct meta_tlvhdr *)(ifehdr->tlv_data); 617 618 spin_lock(&ife->tcf_lock); 619 bstats_update(&ife->tcf_bstats, skb); 620 ife->tcf_tm.lastuse = jiffies; 621 spin_unlock(&ife->tcf_lock); 622 623 ifehdrln = ntohs(ifehdrln); 624 if (unlikely(!pskb_may_pull(skb, ifehdrln))) { 625 spin_lock(&ife->tcf_lock); 626 ife->tcf_qstats.drops++; 627 spin_unlock(&ife->tcf_lock); 628 return TC_ACT_SHOT; 629 } 630 631 skb_set_mac_header(skb, ifehdrln); 632 __skb_pull(skb, ifehdrln); 633 skb->protocol = eth_type_trans(skb, skb->dev); 634 ifehdrln -= IFE_METAHDRLEN; 635 636 while (ifehdrln > 0) { 637 u8 *tlvdata = (u8 *)tlv; 638 u16 mtype = tlv->type; 639 u16 mlen = tlv->len; 640 641 mtype = ntohs(mtype); 642 mlen = ntohs(mlen); 643 644 if (find_decode_metaid(skb, ife, mtype, (mlen - 4), 645 (void *)(tlvdata + 4))) { 646 /* abuse overlimits to count when we receive metadata 647 * but dont have an ops for it 648 */ 649 pr_info_ratelimited("Unknown metaid %d alnlen %d\n", 650 mtype, mlen); 651 ife->tcf_qstats.overlimits++; 652 } 653 654 tlvdata += mlen; 655 ifehdrln -= mlen; 656 tlv = (struct meta_tlvhdr *)tlvdata; 657 } 658 659 skb_reset_network_header(skb); 660 return action; 661 } 662 663 /*XXX: check if we can do this at install time instead of current 664 * send data path 665 **/ 666 static int ife_get_sz(struct sk_buff *skb, struct tcf_ife_info *ife) 667 { 668 struct tcf_meta_info *e, *n; 669 int tot_run_sz = 0, run_sz = 0; 670 671 list_for_each_entry_safe(e, n, &ife->metalist, metalist) { 672 if (e->ops->check_presence) { 673 run_sz = e->ops->check_presence(skb, e); 674 tot_run_sz += run_sz; 675 } 676 } 677 678 return tot_run_sz; 679 } 680 681 static int tcf_ife_encode(struct sk_buff *skb, const struct tc_action *a, 682 struct tcf_result *res) 683 { 684 struct tcf_ife_info *ife = a->priv; 685 int action = ife->tcf_action; 686 struct ethhdr *oethh; /* outer ether header */ 687 struct ethhdr *iethh; /* inner eth header */ 688 struct tcf_meta_info *e; 689 /* 690 OUTERHDR:TOTMETALEN:{TLVHDR:Metadatum:TLVHDR..}:ORIGDATA 691 where ORIGDATA = original ethernet header ... 692 */ 693 u16 metalen = ife_get_sz(skb, ife); 694 int hdrm = metalen + skb->dev->hard_header_len + IFE_METAHDRLEN; 695 unsigned int skboff = skb->dev->hard_header_len; 696 u32 at = G_TC_AT(skb->tc_verd); 697 int new_len = skb->len + hdrm; 698 bool exceed_mtu = false; 699 int err; 700 701 if (at & AT_EGRESS) { 702 if (new_len > skb->dev->mtu) 703 exceed_mtu = true; 704 } 705 706 spin_lock(&ife->tcf_lock); 707 bstats_update(&ife->tcf_bstats, skb); 708 ife->tcf_tm.lastuse = jiffies; 709 710 if (!metalen) { /* no metadata to send */ 711 /* abuse overlimits to count when we allow packet 712 * with no metadata 713 */ 714 ife->tcf_qstats.overlimits++; 715 spin_unlock(&ife->tcf_lock); 716 return action; 717 } 718 /* could be stupid policy setup or mtu config 719 * so lets be conservative.. */ 720 if ((action == TC_ACT_SHOT) || exceed_mtu) { 721 ife->tcf_qstats.drops++; 722 spin_unlock(&ife->tcf_lock); 723 return TC_ACT_SHOT; 724 } 725 726 iethh = eth_hdr(skb); 727 728 err = skb_cow_head(skb, hdrm); 729 if (unlikely(err)) { 730 ife->tcf_qstats.drops++; 731 spin_unlock(&ife->tcf_lock); 732 return TC_ACT_SHOT; 733 } 734 735 if (!(at & AT_EGRESS)) 736 skb_push(skb, skb->dev->hard_header_len); 737 738 __skb_push(skb, hdrm); 739 memcpy(skb->data, iethh, skb->mac_len); 740 skb_reset_mac_header(skb); 741 oethh = eth_hdr(skb); 742 743 /*total metadata length */ 744 metalen += IFE_METAHDRLEN; 745 metalen = htons(metalen); 746 memcpy((skb->data + skboff), &metalen, IFE_METAHDRLEN); 747 skboff += IFE_METAHDRLEN; 748 749 /* XXX: we dont have a clever way of telling encode to 750 * not repeat some of the computations that are done by 751 * ops->presence_check... 752 */ 753 list_for_each_entry(e, &ife->metalist, metalist) { 754 if (e->ops->encode) { 755 err = e->ops->encode(skb, (void *)(skb->data + skboff), 756 e); 757 } 758 if (err < 0) { 759 /* too corrupt to keep around if overwritten */ 760 ife->tcf_qstats.drops++; 761 spin_unlock(&ife->tcf_lock); 762 return TC_ACT_SHOT; 763 } 764 skboff += err; 765 } 766 767 if (!is_zero_ether_addr(ife->eth_src)) 768 ether_addr_copy(oethh->h_source, ife->eth_src); 769 else 770 ether_addr_copy(oethh->h_source, iethh->h_source); 771 if (!is_zero_ether_addr(ife->eth_dst)) 772 ether_addr_copy(oethh->h_dest, ife->eth_dst); 773 else 774 ether_addr_copy(oethh->h_dest, iethh->h_dest); 775 oethh->h_proto = htons(ife->eth_type); 776 777 if (!(at & AT_EGRESS)) 778 skb_pull(skb, skb->dev->hard_header_len); 779 780 spin_unlock(&ife->tcf_lock); 781 782 return action; 783 } 784 785 static int tcf_ife_act(struct sk_buff *skb, const struct tc_action *a, 786 struct tcf_result *res) 787 { 788 struct tcf_ife_info *ife = a->priv; 789 790 if (ife->flags & IFE_ENCODE) 791 return tcf_ife_encode(skb, a, res); 792 793 if (!(ife->flags & IFE_ENCODE)) 794 return tcf_ife_decode(skb, a, res); 795 796 pr_info_ratelimited("unknown failure(policy neither de/encode\n"); 797 spin_lock(&ife->tcf_lock); 798 bstats_update(&ife->tcf_bstats, skb); 799 ife->tcf_tm.lastuse = jiffies; 800 ife->tcf_qstats.drops++; 801 spin_unlock(&ife->tcf_lock); 802 803 return TC_ACT_SHOT; 804 } 805 806 static int tcf_ife_walker(struct net *net, struct sk_buff *skb, 807 struct netlink_callback *cb, int type, 808 struct tc_action *a) 809 { 810 struct tc_action_net *tn = net_generic(net, ife_net_id); 811 812 return tcf_generic_walker(tn, skb, cb, type, a); 813 } 814 815 static int tcf_ife_search(struct net *net, struct tc_action *a, u32 index) 816 { 817 struct tc_action_net *tn = net_generic(net, ife_net_id); 818 819 return tcf_hash_search(tn, a, index); 820 } 821 822 static struct tc_action_ops act_ife_ops = { 823 .kind = "ife", 824 .type = TCA_ACT_IFE, 825 .owner = THIS_MODULE, 826 .act = tcf_ife_act, 827 .dump = tcf_ife_dump, 828 .cleanup = tcf_ife_cleanup, 829 .init = tcf_ife_init, 830 .walk = tcf_ife_walker, 831 .lookup = tcf_ife_search, 832 }; 833 834 static __net_init int ife_init_net(struct net *net) 835 { 836 struct tc_action_net *tn = net_generic(net, ife_net_id); 837 838 return tc_action_net_init(tn, &act_ife_ops, IFE_TAB_MASK); 839 } 840 841 static void __net_exit ife_exit_net(struct net *net) 842 { 843 struct tc_action_net *tn = net_generic(net, ife_net_id); 844 845 tc_action_net_exit(tn); 846 } 847 848 static struct pernet_operations ife_net_ops = { 849 .init = ife_init_net, 850 .exit = ife_exit_net, 851 .id = &ife_net_id, 852 .size = sizeof(struct tc_action_net), 853 }; 854 855 static int __init ife_init_module(void) 856 { 857 return tcf_register_action(&act_ife_ops, &ife_net_ops); 858 } 859 860 static void __exit ife_cleanup_module(void) 861 { 862 tcf_unregister_action(&act_ife_ops, &ife_net_ops); 863 } 864 865 module_init(ife_init_module); 866 module_exit(ife_cleanup_module); 867 868 MODULE_AUTHOR("Jamal Hadi Salim(2015)"); 869 MODULE_DESCRIPTION("Inter-FE LFB action"); 870 MODULE_LICENSE("GPL"); 871