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 #include <net/ife.h> 36 37 static unsigned int ife_net_id; 38 static int max_metacnt = IFE_META_MAX + 1; 39 static struct tc_action_ops act_ife_ops; 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 int ife_encode_meta_u16(u16 metaval, void *skbdata, struct tcf_meta_info *mi) 49 { 50 u16 edata = 0; 51 52 if (mi->metaval) 53 edata = *(u16 *)mi->metaval; 54 else if (metaval) 55 edata = metaval; 56 57 if (!edata) /* will not encode */ 58 return 0; 59 60 edata = htons(edata); 61 return ife_tlv_meta_encode(skbdata, mi->metaid, 2, &edata); 62 } 63 EXPORT_SYMBOL_GPL(ife_encode_meta_u16); 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_check_meta_u16(u16 metaval, struct tcf_meta_info *mi) 84 { 85 if (metaval || mi->metaval) 86 return 8; /* T+L+(V) == 2+2+(2+2bytepad) */ 87 88 return 0; 89 } 90 EXPORT_SYMBOL_GPL(ife_check_meta_u16); 91 92 int ife_encode_meta_u32(u32 metaval, void *skbdata, struct tcf_meta_info *mi) 93 { 94 u32 edata = metaval; 95 96 if (mi->metaval) 97 edata = *(u32 *)mi->metaval; 98 else if (metaval) 99 edata = metaval; 100 101 if (!edata) /* will not encode */ 102 return 0; 103 104 edata = htonl(edata); 105 return ife_tlv_meta_encode(skbdata, mi->metaid, 4, &edata); 106 } 107 EXPORT_SYMBOL_GPL(ife_encode_meta_u32); 108 109 int ife_get_meta_u16(struct sk_buff *skb, struct tcf_meta_info *mi) 110 { 111 if (mi->metaval) 112 return nla_put_u16(skb, mi->metaid, *(u16 *)mi->metaval); 113 else 114 return nla_put(skb, mi->metaid, 0, NULL); 115 } 116 EXPORT_SYMBOL_GPL(ife_get_meta_u16); 117 118 int ife_alloc_meta_u32(struct tcf_meta_info *mi, void *metaval, gfp_t gfp) 119 { 120 mi->metaval = kmemdup(metaval, sizeof(u32), gfp); 121 if (!mi->metaval) 122 return -ENOMEM; 123 124 return 0; 125 } 126 EXPORT_SYMBOL_GPL(ife_alloc_meta_u32); 127 128 int ife_alloc_meta_u16(struct tcf_meta_info *mi, void *metaval, gfp_t gfp) 129 { 130 mi->metaval = kmemdup(metaval, sizeof(u16), gfp); 131 if (!mi->metaval) 132 return -ENOMEM; 133 134 return 0; 135 } 136 EXPORT_SYMBOL_GPL(ife_alloc_meta_u16); 137 138 void ife_release_meta_gen(struct tcf_meta_info *mi) 139 { 140 kfree(mi->metaval); 141 } 142 EXPORT_SYMBOL_GPL(ife_release_meta_gen); 143 144 int ife_validate_meta_u32(void *val, int len) 145 { 146 if (len == sizeof(u32)) 147 return 0; 148 149 return -EINVAL; 150 } 151 EXPORT_SYMBOL_GPL(ife_validate_meta_u32); 152 153 int ife_validate_meta_u16(void *val, int len) 154 { 155 /* length will not include padding */ 156 if (len == sizeof(u16)) 157 return 0; 158 159 return -EINVAL; 160 } 161 EXPORT_SYMBOL_GPL(ife_validate_meta_u16); 162 163 static LIST_HEAD(ifeoplist); 164 static DEFINE_RWLOCK(ife_mod_lock); 165 166 static struct tcf_meta_ops *find_ife_oplist(u16 metaid) 167 { 168 struct tcf_meta_ops *o; 169 170 read_lock(&ife_mod_lock); 171 list_for_each_entry(o, &ifeoplist, list) { 172 if (o->metaid == metaid) { 173 if (!try_module_get(o->owner)) 174 o = NULL; 175 read_unlock(&ife_mod_lock); 176 return o; 177 } 178 } 179 read_unlock(&ife_mod_lock); 180 181 return NULL; 182 } 183 184 int register_ife_op(struct tcf_meta_ops *mops) 185 { 186 struct tcf_meta_ops *m; 187 188 if (!mops->metaid || !mops->metatype || !mops->name || 189 !mops->check_presence || !mops->encode || !mops->decode || 190 !mops->get || !mops->alloc) 191 return -EINVAL; 192 193 write_lock(&ife_mod_lock); 194 195 list_for_each_entry(m, &ifeoplist, list) { 196 if (m->metaid == mops->metaid || 197 (strcmp(mops->name, m->name) == 0)) { 198 write_unlock(&ife_mod_lock); 199 return -EEXIST; 200 } 201 } 202 203 if (!mops->release) 204 mops->release = ife_release_meta_gen; 205 206 list_add_tail(&mops->list, &ifeoplist); 207 write_unlock(&ife_mod_lock); 208 return 0; 209 } 210 EXPORT_SYMBOL_GPL(unregister_ife_op); 211 212 int unregister_ife_op(struct tcf_meta_ops *mops) 213 { 214 struct tcf_meta_ops *m; 215 int err = -ENOENT; 216 217 write_lock(&ife_mod_lock); 218 list_for_each_entry(m, &ifeoplist, list) { 219 if (m->metaid == mops->metaid) { 220 list_del(&mops->list); 221 err = 0; 222 break; 223 } 224 } 225 write_unlock(&ife_mod_lock); 226 227 return err; 228 } 229 EXPORT_SYMBOL_GPL(register_ife_op); 230 231 static int ife_validate_metatype(struct tcf_meta_ops *ops, void *val, int len) 232 { 233 int ret = 0; 234 /* XXX: unfortunately cant use nla_policy at this point 235 * because a length of 0 is valid in the case of 236 * "allow". "use" semantics do enforce for proper 237 * length and i couldve use nla_policy but it makes it hard 238 * to use it just for that.. 239 */ 240 if (ops->validate) 241 return ops->validate(val, len); 242 243 if (ops->metatype == NLA_U32) 244 ret = ife_validate_meta_u32(val, len); 245 else if (ops->metatype == NLA_U16) 246 ret = ife_validate_meta_u16(val, len); 247 248 return ret; 249 } 250 251 #ifdef CONFIG_MODULES 252 static const char *ife_meta_id2name(u32 metaid) 253 { 254 switch (metaid) { 255 case IFE_META_SKBMARK: 256 return "skbmark"; 257 case IFE_META_PRIO: 258 return "skbprio"; 259 case IFE_META_TCINDEX: 260 return "tcindex"; 261 default: 262 return "unknown"; 263 } 264 } 265 #endif 266 267 /* called when adding new meta information 268 * under ife->tcf_lock for existing action 269 */ 270 static int load_metaops_and_vet(struct tcf_ife_info *ife, u32 metaid, 271 void *val, int len, bool exists) 272 { 273 struct tcf_meta_ops *ops = find_ife_oplist(metaid); 274 int ret = 0; 275 276 if (!ops) { 277 ret = -ENOENT; 278 #ifdef CONFIG_MODULES 279 if (exists) 280 spin_unlock_bh(&ife->tcf_lock); 281 rtnl_unlock(); 282 request_module("ife-meta-%s", ife_meta_id2name(metaid)); 283 rtnl_lock(); 284 if (exists) 285 spin_lock_bh(&ife->tcf_lock); 286 ops = find_ife_oplist(metaid); 287 #endif 288 } 289 290 if (ops) { 291 ret = 0; 292 if (len) 293 ret = ife_validate_metatype(ops, val, len); 294 295 module_put(ops->owner); 296 } 297 298 return ret; 299 } 300 301 /* called when adding new meta information 302 * under ife->tcf_lock for existing action 303 */ 304 static int add_metainfo(struct tcf_ife_info *ife, u32 metaid, void *metaval, 305 int len, bool atomic) 306 { 307 struct tcf_meta_info *mi = NULL; 308 struct tcf_meta_ops *ops = find_ife_oplist(metaid); 309 int ret = 0; 310 311 if (!ops) 312 return -ENOENT; 313 314 mi = kzalloc(sizeof(*mi), atomic ? GFP_ATOMIC : GFP_KERNEL); 315 if (!mi) { 316 /*put back what find_ife_oplist took */ 317 module_put(ops->owner); 318 return -ENOMEM; 319 } 320 321 mi->metaid = metaid; 322 mi->ops = ops; 323 if (len > 0) { 324 ret = ops->alloc(mi, metaval, atomic ? GFP_ATOMIC : GFP_KERNEL); 325 if (ret != 0) { 326 kfree(mi); 327 module_put(ops->owner); 328 return ret; 329 } 330 } 331 332 list_add_tail(&mi->metalist, &ife->metalist); 333 334 return ret; 335 } 336 337 static int use_all_metadata(struct tcf_ife_info *ife) 338 { 339 struct tcf_meta_ops *o; 340 int rc = 0; 341 int installed = 0; 342 343 read_lock(&ife_mod_lock); 344 list_for_each_entry(o, &ifeoplist, list) { 345 rc = add_metainfo(ife, o->metaid, NULL, 0, true); 346 if (rc == 0) 347 installed += 1; 348 } 349 read_unlock(&ife_mod_lock); 350 351 if (installed) 352 return 0; 353 else 354 return -EINVAL; 355 } 356 357 static int dump_metalist(struct sk_buff *skb, struct tcf_ife_info *ife) 358 { 359 struct tcf_meta_info *e; 360 struct nlattr *nest; 361 unsigned char *b = skb_tail_pointer(skb); 362 int total_encoded = 0; 363 364 /*can only happen on decode */ 365 if (list_empty(&ife->metalist)) 366 return 0; 367 368 nest = nla_nest_start(skb, TCA_IFE_METALST); 369 if (!nest) 370 goto out_nlmsg_trim; 371 372 list_for_each_entry(e, &ife->metalist, metalist) { 373 if (!e->ops->get(skb, e)) 374 total_encoded += 1; 375 } 376 377 if (!total_encoded) 378 goto out_nlmsg_trim; 379 380 nla_nest_end(skb, nest); 381 382 return 0; 383 384 out_nlmsg_trim: 385 nlmsg_trim(skb, b); 386 return -1; 387 } 388 389 /* under ife->tcf_lock */ 390 static void _tcf_ife_cleanup(struct tc_action *a) 391 { 392 struct tcf_ife_info *ife = to_ife(a); 393 struct tcf_meta_info *e, *n; 394 395 list_for_each_entry_safe(e, n, &ife->metalist, metalist) { 396 module_put(e->ops->owner); 397 list_del(&e->metalist); 398 if (e->metaval) { 399 if (e->ops->release) 400 e->ops->release(e); 401 else 402 kfree(e->metaval); 403 } 404 kfree(e); 405 } 406 } 407 408 static void tcf_ife_cleanup(struct tc_action *a) 409 { 410 struct tcf_ife_info *ife = to_ife(a); 411 struct tcf_ife_params *p; 412 413 spin_lock_bh(&ife->tcf_lock); 414 _tcf_ife_cleanup(a); 415 spin_unlock_bh(&ife->tcf_lock); 416 417 p = rcu_dereference_protected(ife->params, 1); 418 kfree_rcu(p, rcu); 419 } 420 421 /* under ife->tcf_lock for existing action */ 422 static int populate_metalist(struct tcf_ife_info *ife, struct nlattr **tb, 423 bool exists) 424 { 425 int len = 0; 426 int rc = 0; 427 int i = 0; 428 void *val; 429 430 for (i = 1; i < max_metacnt; i++) { 431 if (tb[i]) { 432 val = nla_data(tb[i]); 433 len = nla_len(tb[i]); 434 435 rc = load_metaops_and_vet(ife, i, val, len, exists); 436 if (rc != 0) 437 return rc; 438 439 rc = add_metainfo(ife, i, val, len, exists); 440 if (rc) 441 return rc; 442 } 443 } 444 445 return rc; 446 } 447 448 static int tcf_ife_init(struct net *net, struct nlattr *nla, 449 struct nlattr *est, struct tc_action **a, 450 int ovr, int bind) 451 { 452 struct tc_action_net *tn = net_generic(net, ife_net_id); 453 struct nlattr *tb[TCA_IFE_MAX + 1]; 454 struct nlattr *tb2[IFE_META_MAX + 1]; 455 struct tcf_ife_params *p, *p_old; 456 struct tcf_ife_info *ife; 457 u16 ife_type = ETH_P_IFE; 458 struct tc_ife *parm; 459 u8 *daddr = NULL; 460 u8 *saddr = NULL; 461 bool exists = false; 462 int ret = 0; 463 int err; 464 465 err = nla_parse_nested(tb, TCA_IFE_MAX, nla, ife_policy, NULL); 466 if (err < 0) 467 return err; 468 469 if (!tb[TCA_IFE_PARMS]) 470 return -EINVAL; 471 472 parm = nla_data(tb[TCA_IFE_PARMS]); 473 474 /* IFE_DECODE is 0 and indicates the opposite of IFE_ENCODE because 475 * they cannot run as the same time. Check on all other values which 476 * are not supported right now. 477 */ 478 if (parm->flags & ~IFE_ENCODE) 479 return -EINVAL; 480 481 p = kzalloc(sizeof(*p), GFP_KERNEL); 482 if (!p) 483 return -ENOMEM; 484 485 exists = tcf_idr_check(tn, parm->index, a, bind); 486 if (exists && bind) { 487 kfree(p); 488 return 0; 489 } 490 491 if (!exists) { 492 ret = tcf_idr_create(tn, parm->index, est, a, &act_ife_ops, 493 bind, true); 494 if (ret) { 495 kfree(p); 496 return ret; 497 } 498 ret = ACT_P_CREATED; 499 } else { 500 tcf_idr_release(*a, bind); 501 if (!ovr) { 502 kfree(p); 503 return -EEXIST; 504 } 505 } 506 507 ife = to_ife(*a); 508 p->flags = parm->flags; 509 510 if (parm->flags & IFE_ENCODE) { 511 if (tb[TCA_IFE_TYPE]) 512 ife_type = nla_get_u16(tb[TCA_IFE_TYPE]); 513 if (tb[TCA_IFE_DMAC]) 514 daddr = nla_data(tb[TCA_IFE_DMAC]); 515 if (tb[TCA_IFE_SMAC]) 516 saddr = nla_data(tb[TCA_IFE_SMAC]); 517 } 518 519 ife->tcf_action = parm->action; 520 521 if (parm->flags & IFE_ENCODE) { 522 if (daddr) 523 ether_addr_copy(p->eth_dst, daddr); 524 else 525 eth_zero_addr(p->eth_dst); 526 527 if (saddr) 528 ether_addr_copy(p->eth_src, saddr); 529 else 530 eth_zero_addr(p->eth_src); 531 532 p->eth_type = ife_type; 533 } 534 535 if (exists) 536 spin_lock_bh(&ife->tcf_lock); 537 538 if (ret == ACT_P_CREATED) 539 INIT_LIST_HEAD(&ife->metalist); 540 541 if (tb[TCA_IFE_METALST]) { 542 err = nla_parse_nested(tb2, IFE_META_MAX, tb[TCA_IFE_METALST], 543 NULL, NULL); 544 if (err) { 545 metadata_parse_err: 546 if (exists) 547 tcf_idr_release(*a, bind); 548 if (ret == ACT_P_CREATED) 549 _tcf_ife_cleanup(*a); 550 551 if (exists) 552 spin_unlock_bh(&ife->tcf_lock); 553 kfree(p); 554 return err; 555 } 556 557 err = populate_metalist(ife, tb2, exists); 558 if (err) 559 goto metadata_parse_err; 560 561 } else { 562 /* if no passed metadata allow list or passed allow-all 563 * then here we process by adding as many supported metadatum 564 * as we can. You better have at least one else we are 565 * going to bail out 566 */ 567 err = use_all_metadata(ife); 568 if (err) { 569 if (ret == ACT_P_CREATED) 570 _tcf_ife_cleanup(*a); 571 572 if (exists) 573 spin_unlock_bh(&ife->tcf_lock); 574 kfree(p); 575 return err; 576 } 577 } 578 579 if (exists) 580 spin_unlock_bh(&ife->tcf_lock); 581 582 p_old = rtnl_dereference(ife->params); 583 rcu_assign_pointer(ife->params, p); 584 if (p_old) 585 kfree_rcu(p_old, rcu); 586 587 if (ret == ACT_P_CREATED) 588 tcf_idr_insert(tn, *a); 589 590 return ret; 591 } 592 593 static int tcf_ife_dump(struct sk_buff *skb, struct tc_action *a, int bind, 594 int ref) 595 { 596 unsigned char *b = skb_tail_pointer(skb); 597 struct tcf_ife_info *ife = to_ife(a); 598 struct tcf_ife_params *p = rtnl_dereference(ife->params); 599 struct tc_ife opt = { 600 .index = ife->tcf_index, 601 .refcnt = ife->tcf_refcnt - ref, 602 .bindcnt = ife->tcf_bindcnt - bind, 603 .action = ife->tcf_action, 604 .flags = p->flags, 605 }; 606 struct tcf_t t; 607 608 if (nla_put(skb, TCA_IFE_PARMS, sizeof(opt), &opt)) 609 goto nla_put_failure; 610 611 tcf_tm_dump(&t, &ife->tcf_tm); 612 if (nla_put_64bit(skb, TCA_IFE_TM, sizeof(t), &t, TCA_IFE_PAD)) 613 goto nla_put_failure; 614 615 if (!is_zero_ether_addr(p->eth_dst)) { 616 if (nla_put(skb, TCA_IFE_DMAC, ETH_ALEN, p->eth_dst)) 617 goto nla_put_failure; 618 } 619 620 if (!is_zero_ether_addr(p->eth_src)) { 621 if (nla_put(skb, TCA_IFE_SMAC, ETH_ALEN, p->eth_src)) 622 goto nla_put_failure; 623 } 624 625 if (nla_put(skb, TCA_IFE_TYPE, 2, &p->eth_type)) 626 goto nla_put_failure; 627 628 if (dump_metalist(skb, ife)) { 629 /*ignore failure to dump metalist */ 630 pr_info("Failed to dump metalist\n"); 631 } 632 633 return skb->len; 634 635 nla_put_failure: 636 nlmsg_trim(skb, b); 637 return -1; 638 } 639 640 static int find_decode_metaid(struct sk_buff *skb, struct tcf_ife_info *ife, 641 u16 metaid, u16 mlen, void *mdata) 642 { 643 struct tcf_meta_info *e; 644 645 /* XXX: use hash to speed up */ 646 list_for_each_entry(e, &ife->metalist, metalist) { 647 if (metaid == e->metaid) { 648 if (e->ops) { 649 /* We check for decode presence already */ 650 return e->ops->decode(skb, mdata, mlen); 651 } 652 } 653 } 654 655 return 0; 656 } 657 658 static int tcf_ife_decode(struct sk_buff *skb, const struct tc_action *a, 659 struct tcf_result *res) 660 { 661 struct tcf_ife_info *ife = to_ife(a); 662 int action = ife->tcf_action; 663 u8 *ifehdr_end; 664 u8 *tlv_data; 665 u16 metalen; 666 667 bstats_cpu_update(this_cpu_ptr(ife->common.cpu_bstats), skb); 668 tcf_lastuse_update(&ife->tcf_tm); 669 670 if (skb_at_tc_ingress(skb)) 671 skb_push(skb, skb->dev->hard_header_len); 672 673 tlv_data = ife_decode(skb, &metalen); 674 if (unlikely(!tlv_data)) { 675 qstats_drop_inc(this_cpu_ptr(ife->common.cpu_qstats)); 676 return TC_ACT_SHOT; 677 } 678 679 ifehdr_end = tlv_data + metalen; 680 for (; tlv_data < ifehdr_end; tlv_data = ife_tlv_meta_next(tlv_data)) { 681 u8 *curr_data; 682 u16 mtype; 683 u16 dlen; 684 685 curr_data = ife_tlv_meta_decode(tlv_data, &mtype, &dlen, NULL); 686 687 if (find_decode_metaid(skb, ife, mtype, dlen, curr_data)) { 688 /* abuse overlimits to count when we receive metadata 689 * but dont have an ops for it 690 */ 691 pr_info_ratelimited("Unknown metaid %d dlen %d\n", 692 mtype, dlen); 693 qstats_overlimit_inc(this_cpu_ptr(ife->common.cpu_qstats)); 694 } 695 } 696 697 if (WARN_ON(tlv_data != ifehdr_end)) { 698 qstats_drop_inc(this_cpu_ptr(ife->common.cpu_qstats)); 699 return TC_ACT_SHOT; 700 } 701 702 skb->protocol = eth_type_trans(skb, skb->dev); 703 skb_reset_network_header(skb); 704 705 return action; 706 } 707 708 /*XXX: check if we can do this at install time instead of current 709 * send data path 710 **/ 711 static int ife_get_sz(struct sk_buff *skb, struct tcf_ife_info *ife) 712 { 713 struct tcf_meta_info *e, *n; 714 int tot_run_sz = 0, run_sz = 0; 715 716 list_for_each_entry_safe(e, n, &ife->metalist, metalist) { 717 if (e->ops->check_presence) { 718 run_sz = e->ops->check_presence(skb, e); 719 tot_run_sz += run_sz; 720 } 721 } 722 723 return tot_run_sz; 724 } 725 726 static int tcf_ife_encode(struct sk_buff *skb, const struct tc_action *a, 727 struct tcf_result *res, struct tcf_ife_params *p) 728 { 729 struct tcf_ife_info *ife = to_ife(a); 730 int action = ife->tcf_action; 731 struct ethhdr *oethh; /* outer ether header */ 732 struct tcf_meta_info *e; 733 /* 734 OUTERHDR:TOTMETALEN:{TLVHDR:Metadatum:TLVHDR..}:ORIGDATA 735 where ORIGDATA = original ethernet header ... 736 */ 737 u16 metalen = ife_get_sz(skb, ife); 738 int hdrm = metalen + skb->dev->hard_header_len + IFE_METAHDRLEN; 739 unsigned int skboff = 0; 740 int new_len = skb->len + hdrm; 741 bool exceed_mtu = false; 742 void *ife_meta; 743 int err = 0; 744 745 if (!skb_at_tc_ingress(skb)) { 746 if (new_len > skb->dev->mtu) 747 exceed_mtu = true; 748 } 749 750 bstats_cpu_update(this_cpu_ptr(ife->common.cpu_bstats), skb); 751 tcf_lastuse_update(&ife->tcf_tm); 752 753 if (!metalen) { /* no metadata to send */ 754 /* abuse overlimits to count when we allow packet 755 * with no metadata 756 */ 757 qstats_overlimit_inc(this_cpu_ptr(ife->common.cpu_qstats)); 758 return action; 759 } 760 /* could be stupid policy setup or mtu config 761 * so lets be conservative.. */ 762 if ((action == TC_ACT_SHOT) || exceed_mtu) { 763 qstats_drop_inc(this_cpu_ptr(ife->common.cpu_qstats)); 764 return TC_ACT_SHOT; 765 } 766 767 if (skb_at_tc_ingress(skb)) 768 skb_push(skb, skb->dev->hard_header_len); 769 770 ife_meta = ife_encode(skb, metalen); 771 772 spin_lock(&ife->tcf_lock); 773 774 /* XXX: we dont have a clever way of telling encode to 775 * not repeat some of the computations that are done by 776 * ops->presence_check... 777 */ 778 list_for_each_entry(e, &ife->metalist, metalist) { 779 if (e->ops->encode) { 780 err = e->ops->encode(skb, (void *)(ife_meta + skboff), 781 e); 782 } 783 if (err < 0) { 784 /* too corrupt to keep around if overwritten */ 785 spin_unlock(&ife->tcf_lock); 786 qstats_drop_inc(this_cpu_ptr(ife->common.cpu_qstats)); 787 return TC_ACT_SHOT; 788 } 789 skboff += err; 790 } 791 spin_unlock(&ife->tcf_lock); 792 oethh = (struct ethhdr *)skb->data; 793 794 if (!is_zero_ether_addr(p->eth_src)) 795 ether_addr_copy(oethh->h_source, p->eth_src); 796 if (!is_zero_ether_addr(p->eth_dst)) 797 ether_addr_copy(oethh->h_dest, p->eth_dst); 798 oethh->h_proto = htons(p->eth_type); 799 800 if (skb_at_tc_ingress(skb)) 801 skb_pull(skb, skb->dev->hard_header_len); 802 803 return action; 804 } 805 806 static int tcf_ife_act(struct sk_buff *skb, const struct tc_action *a, 807 struct tcf_result *res) 808 { 809 struct tcf_ife_info *ife = to_ife(a); 810 struct tcf_ife_params *p; 811 int ret; 812 813 rcu_read_lock(); 814 p = rcu_dereference(ife->params); 815 if (p->flags & IFE_ENCODE) { 816 ret = tcf_ife_encode(skb, a, res, p); 817 rcu_read_unlock(); 818 return ret; 819 } 820 rcu_read_unlock(); 821 822 return tcf_ife_decode(skb, a, res); 823 } 824 825 static int tcf_ife_walker(struct net *net, struct sk_buff *skb, 826 struct netlink_callback *cb, int type, 827 const struct tc_action_ops *ops) 828 { 829 struct tc_action_net *tn = net_generic(net, ife_net_id); 830 831 return tcf_generic_walker(tn, skb, cb, type, ops); 832 } 833 834 static int tcf_ife_search(struct net *net, struct tc_action **a, u32 index) 835 { 836 struct tc_action_net *tn = net_generic(net, ife_net_id); 837 838 return tcf_idr_search(tn, a, index); 839 } 840 841 static struct tc_action_ops act_ife_ops = { 842 .kind = "ife", 843 .type = TCA_ACT_IFE, 844 .owner = THIS_MODULE, 845 .act = tcf_ife_act, 846 .dump = tcf_ife_dump, 847 .cleanup = tcf_ife_cleanup, 848 .init = tcf_ife_init, 849 .walk = tcf_ife_walker, 850 .lookup = tcf_ife_search, 851 .size = sizeof(struct tcf_ife_info), 852 }; 853 854 static __net_init int ife_init_net(struct net *net) 855 { 856 struct tc_action_net *tn = net_generic(net, ife_net_id); 857 858 return tc_action_net_init(tn, &act_ife_ops); 859 } 860 861 static void __net_exit ife_exit_net(struct list_head *net_list) 862 { 863 tc_action_net_exit(net_list, ife_net_id); 864 } 865 866 static struct pernet_operations ife_net_ops = { 867 .init = ife_init_net, 868 .exit_batch = ife_exit_net, 869 .id = &ife_net_id, 870 .size = sizeof(struct tc_action_net), 871 }; 872 873 static int __init ife_init_module(void) 874 { 875 return tcf_register_action(&act_ife_ops, &ife_net_ops); 876 } 877 878 static void __exit ife_cleanup_module(void) 879 { 880 tcf_unregister_action(&act_ife_ops, &ife_net_ops); 881 } 882 883 module_init(ife_init_module); 884 module_exit(ife_cleanup_module); 885 886 MODULE_AUTHOR("Jamal Hadi Salim(2015)"); 887 MODULE_DESCRIPTION("Inter-FE LFB action"); 888 MODULE_LICENSE("GPL"); 889