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 */ 269 static int load_metaops_and_vet(u32 metaid, void *val, int len, bool rtnl_held) 270 { 271 struct tcf_meta_ops *ops = find_ife_oplist(metaid); 272 int ret = 0; 273 274 if (!ops) { 275 ret = -ENOENT; 276 #ifdef CONFIG_MODULES 277 if (rtnl_held) 278 rtnl_unlock(); 279 request_module("ife-meta-%s", ife_meta_id2name(metaid)); 280 if (rtnl_held) 281 rtnl_lock(); 282 ops = find_ife_oplist(metaid); 283 #endif 284 } 285 286 if (ops) { 287 ret = 0; 288 if (len) 289 ret = ife_validate_metatype(ops, val, len); 290 291 module_put(ops->owner); 292 } 293 294 return ret; 295 } 296 297 /* called when adding new meta information 298 */ 299 static int __add_metainfo(const struct tcf_meta_ops *ops, 300 struct tcf_ife_info *ife, u32 metaid, void *metaval, 301 int len, bool atomic, bool exists) 302 { 303 struct tcf_meta_info *mi = NULL; 304 int ret = 0; 305 306 mi = kzalloc(sizeof(*mi), atomic ? GFP_ATOMIC : GFP_KERNEL); 307 if (!mi) 308 return -ENOMEM; 309 310 mi->metaid = metaid; 311 mi->ops = ops; 312 if (len > 0) { 313 ret = ops->alloc(mi, metaval, atomic ? GFP_ATOMIC : GFP_KERNEL); 314 if (ret != 0) { 315 kfree(mi); 316 return ret; 317 } 318 } 319 320 if (exists) 321 spin_lock_bh(&ife->tcf_lock); 322 list_add_tail(&mi->metalist, &ife->metalist); 323 if (exists) 324 spin_unlock_bh(&ife->tcf_lock); 325 326 return ret; 327 } 328 329 static int add_metainfo_and_get_ops(const struct tcf_meta_ops *ops, 330 struct tcf_ife_info *ife, u32 metaid, 331 bool exists) 332 { 333 int ret; 334 335 if (!try_module_get(ops->owner)) 336 return -ENOENT; 337 ret = __add_metainfo(ops, ife, metaid, NULL, 0, true, exists); 338 if (ret) 339 module_put(ops->owner); 340 return ret; 341 } 342 343 static int add_metainfo(struct tcf_ife_info *ife, u32 metaid, void *metaval, 344 int len, bool exists) 345 { 346 const struct tcf_meta_ops *ops = find_ife_oplist(metaid); 347 int ret; 348 349 if (!ops) 350 return -ENOENT; 351 ret = __add_metainfo(ops, ife, metaid, metaval, len, false, exists); 352 if (ret) 353 /*put back what find_ife_oplist took */ 354 module_put(ops->owner); 355 return ret; 356 } 357 358 static int use_all_metadata(struct tcf_ife_info *ife, bool exists) 359 { 360 struct tcf_meta_ops *o; 361 int rc = 0; 362 int installed = 0; 363 364 read_lock(&ife_mod_lock); 365 list_for_each_entry(o, &ifeoplist, list) { 366 rc = add_metainfo_and_get_ops(o, ife, o->metaid, exists); 367 if (rc == 0) 368 installed += 1; 369 } 370 read_unlock(&ife_mod_lock); 371 372 if (installed) 373 return 0; 374 else 375 return -EINVAL; 376 } 377 378 static int dump_metalist(struct sk_buff *skb, struct tcf_ife_info *ife) 379 { 380 struct tcf_meta_info *e; 381 struct nlattr *nest; 382 unsigned char *b = skb_tail_pointer(skb); 383 int total_encoded = 0; 384 385 /*can only happen on decode */ 386 if (list_empty(&ife->metalist)) 387 return 0; 388 389 nest = nla_nest_start(skb, TCA_IFE_METALST); 390 if (!nest) 391 goto out_nlmsg_trim; 392 393 list_for_each_entry(e, &ife->metalist, metalist) { 394 if (!e->ops->get(skb, e)) 395 total_encoded += 1; 396 } 397 398 if (!total_encoded) 399 goto out_nlmsg_trim; 400 401 nla_nest_end(skb, nest); 402 403 return 0; 404 405 out_nlmsg_trim: 406 nlmsg_trim(skb, b); 407 return -1; 408 } 409 410 /* under ife->tcf_lock */ 411 static void _tcf_ife_cleanup(struct tc_action *a) 412 { 413 struct tcf_ife_info *ife = to_ife(a); 414 struct tcf_meta_info *e, *n; 415 416 list_for_each_entry_safe(e, n, &ife->metalist, metalist) { 417 list_del(&e->metalist); 418 if (e->metaval) { 419 if (e->ops->release) 420 e->ops->release(e); 421 else 422 kfree(e->metaval); 423 } 424 module_put(e->ops->owner); 425 kfree(e); 426 } 427 } 428 429 static void tcf_ife_cleanup(struct tc_action *a) 430 { 431 struct tcf_ife_info *ife = to_ife(a); 432 struct tcf_ife_params *p; 433 434 spin_lock_bh(&ife->tcf_lock); 435 _tcf_ife_cleanup(a); 436 spin_unlock_bh(&ife->tcf_lock); 437 438 p = rcu_dereference_protected(ife->params, 1); 439 if (p) 440 kfree_rcu(p, rcu); 441 } 442 443 static int populate_metalist(struct tcf_ife_info *ife, struct nlattr **tb, 444 bool exists, bool rtnl_held) 445 { 446 int len = 0; 447 int rc = 0; 448 int i = 0; 449 void *val; 450 451 for (i = 1; i < max_metacnt; i++) { 452 if (tb[i]) { 453 val = nla_data(tb[i]); 454 len = nla_len(tb[i]); 455 456 rc = load_metaops_and_vet(i, val, len, rtnl_held); 457 if (rc != 0) 458 return rc; 459 460 rc = add_metainfo(ife, i, val, len, exists); 461 if (rc) 462 return rc; 463 } 464 } 465 466 return rc; 467 } 468 469 static int tcf_ife_init(struct net *net, struct nlattr *nla, 470 struct nlattr *est, struct tc_action **a, 471 int ovr, int bind, bool rtnl_held, 472 struct netlink_ext_ack *extack) 473 { 474 struct tc_action_net *tn = net_generic(net, ife_net_id); 475 struct nlattr *tb[TCA_IFE_MAX + 1]; 476 struct nlattr *tb2[IFE_META_MAX + 1]; 477 struct tcf_ife_params *p; 478 struct tcf_ife_info *ife; 479 u16 ife_type = ETH_P_IFE; 480 struct tc_ife *parm; 481 u8 *daddr = NULL; 482 u8 *saddr = NULL; 483 bool exists = false; 484 int ret = 0; 485 int err; 486 487 err = nla_parse_nested(tb, TCA_IFE_MAX, nla, ife_policy, NULL); 488 if (err < 0) 489 return err; 490 491 if (!tb[TCA_IFE_PARMS]) 492 return -EINVAL; 493 494 parm = nla_data(tb[TCA_IFE_PARMS]); 495 496 /* IFE_DECODE is 0 and indicates the opposite of IFE_ENCODE because 497 * they cannot run as the same time. Check on all other values which 498 * are not supported right now. 499 */ 500 if (parm->flags & ~IFE_ENCODE) 501 return -EINVAL; 502 503 p = kzalloc(sizeof(*p), GFP_KERNEL); 504 if (!p) 505 return -ENOMEM; 506 507 err = tcf_idr_check_alloc(tn, &parm->index, a, bind); 508 if (err < 0) { 509 kfree(p); 510 return err; 511 } 512 exists = err; 513 if (exists && bind) { 514 kfree(p); 515 return 0; 516 } 517 518 if (!exists) { 519 ret = tcf_idr_create(tn, parm->index, est, a, &act_ife_ops, 520 bind, true); 521 if (ret) { 522 tcf_idr_cleanup(tn, parm->index); 523 kfree(p); 524 return ret; 525 } 526 ret = ACT_P_CREATED; 527 } else if (!ovr) { 528 tcf_idr_release(*a, bind); 529 kfree(p); 530 return -EEXIST; 531 } 532 533 ife = to_ife(*a); 534 p->flags = parm->flags; 535 536 if (parm->flags & IFE_ENCODE) { 537 if (tb[TCA_IFE_TYPE]) 538 ife_type = nla_get_u16(tb[TCA_IFE_TYPE]); 539 if (tb[TCA_IFE_DMAC]) 540 daddr = nla_data(tb[TCA_IFE_DMAC]); 541 if (tb[TCA_IFE_SMAC]) 542 saddr = nla_data(tb[TCA_IFE_SMAC]); 543 } 544 545 if (parm->flags & IFE_ENCODE) { 546 if (daddr) 547 ether_addr_copy(p->eth_dst, daddr); 548 else 549 eth_zero_addr(p->eth_dst); 550 551 if (saddr) 552 ether_addr_copy(p->eth_src, saddr); 553 else 554 eth_zero_addr(p->eth_src); 555 556 p->eth_type = ife_type; 557 } 558 559 560 if (ret == ACT_P_CREATED) 561 INIT_LIST_HEAD(&ife->metalist); 562 563 if (tb[TCA_IFE_METALST]) { 564 err = nla_parse_nested(tb2, IFE_META_MAX, tb[TCA_IFE_METALST], 565 NULL, NULL); 566 if (err) { 567 metadata_parse_err: 568 tcf_idr_release(*a, bind); 569 kfree(p); 570 return err; 571 } 572 573 err = populate_metalist(ife, tb2, exists, rtnl_held); 574 if (err) 575 goto metadata_parse_err; 576 577 } else { 578 /* if no passed metadata allow list or passed allow-all 579 * then here we process by adding as many supported metadatum 580 * as we can. You better have at least one else we are 581 * going to bail out 582 */ 583 err = use_all_metadata(ife, exists); 584 if (err) { 585 tcf_idr_release(*a, bind); 586 kfree(p); 587 return err; 588 } 589 } 590 591 if (exists) 592 spin_lock_bh(&ife->tcf_lock); 593 ife->tcf_action = parm->action; 594 /* protected by tcf_lock when modifying existing action */ 595 rcu_swap_protected(ife->params, p, 1); 596 597 if (exists) 598 spin_unlock_bh(&ife->tcf_lock); 599 if (p) 600 kfree_rcu(p, rcu); 601 602 if (ret == ACT_P_CREATED) 603 tcf_idr_insert(tn, *a); 604 605 return ret; 606 } 607 608 static int tcf_ife_dump(struct sk_buff *skb, struct tc_action *a, int bind, 609 int ref) 610 { 611 unsigned char *b = skb_tail_pointer(skb); 612 struct tcf_ife_info *ife = to_ife(a); 613 struct tcf_ife_params *p; 614 struct tc_ife opt = { 615 .index = ife->tcf_index, 616 .refcnt = refcount_read(&ife->tcf_refcnt) - ref, 617 .bindcnt = atomic_read(&ife->tcf_bindcnt) - bind, 618 }; 619 struct tcf_t t; 620 621 spin_lock_bh(&ife->tcf_lock); 622 opt.action = ife->tcf_action; 623 p = rcu_dereference_protected(ife->params, 624 lockdep_is_held(&ife->tcf_lock)); 625 opt.flags = p->flags; 626 627 if (nla_put(skb, TCA_IFE_PARMS, sizeof(opt), &opt)) 628 goto nla_put_failure; 629 630 tcf_tm_dump(&t, &ife->tcf_tm); 631 if (nla_put_64bit(skb, TCA_IFE_TM, sizeof(t), &t, TCA_IFE_PAD)) 632 goto nla_put_failure; 633 634 if (!is_zero_ether_addr(p->eth_dst)) { 635 if (nla_put(skb, TCA_IFE_DMAC, ETH_ALEN, p->eth_dst)) 636 goto nla_put_failure; 637 } 638 639 if (!is_zero_ether_addr(p->eth_src)) { 640 if (nla_put(skb, TCA_IFE_SMAC, ETH_ALEN, p->eth_src)) 641 goto nla_put_failure; 642 } 643 644 if (nla_put(skb, TCA_IFE_TYPE, 2, &p->eth_type)) 645 goto nla_put_failure; 646 647 if (dump_metalist(skb, ife)) { 648 /*ignore failure to dump metalist */ 649 pr_info("Failed to dump metalist\n"); 650 } 651 652 spin_unlock_bh(&ife->tcf_lock); 653 return skb->len; 654 655 nla_put_failure: 656 spin_unlock_bh(&ife->tcf_lock); 657 nlmsg_trim(skb, b); 658 return -1; 659 } 660 661 static int find_decode_metaid(struct sk_buff *skb, struct tcf_ife_info *ife, 662 u16 metaid, u16 mlen, void *mdata) 663 { 664 struct tcf_meta_info *e; 665 666 /* XXX: use hash to speed up */ 667 list_for_each_entry(e, &ife->metalist, metalist) { 668 if (metaid == e->metaid) { 669 if (e->ops) { 670 /* We check for decode presence already */ 671 return e->ops->decode(skb, mdata, mlen); 672 } 673 } 674 } 675 676 return -ENOENT; 677 } 678 679 static int tcf_ife_decode(struct sk_buff *skb, const struct tc_action *a, 680 struct tcf_result *res) 681 { 682 struct tcf_ife_info *ife = to_ife(a); 683 int action = ife->tcf_action; 684 u8 *ifehdr_end; 685 u8 *tlv_data; 686 u16 metalen; 687 688 bstats_cpu_update(this_cpu_ptr(ife->common.cpu_bstats), skb); 689 tcf_lastuse_update(&ife->tcf_tm); 690 691 if (skb_at_tc_ingress(skb)) 692 skb_push(skb, skb->dev->hard_header_len); 693 694 tlv_data = ife_decode(skb, &metalen); 695 if (unlikely(!tlv_data)) { 696 qstats_drop_inc(this_cpu_ptr(ife->common.cpu_qstats)); 697 return TC_ACT_SHOT; 698 } 699 700 ifehdr_end = tlv_data + metalen; 701 for (; tlv_data < ifehdr_end; tlv_data = ife_tlv_meta_next(tlv_data)) { 702 u8 *curr_data; 703 u16 mtype; 704 u16 dlen; 705 706 curr_data = ife_tlv_meta_decode(tlv_data, ifehdr_end, &mtype, 707 &dlen, NULL); 708 if (!curr_data) { 709 qstats_drop_inc(this_cpu_ptr(ife->common.cpu_qstats)); 710 return TC_ACT_SHOT; 711 } 712 713 if (find_decode_metaid(skb, ife, mtype, dlen, curr_data)) { 714 /* abuse overlimits to count when we receive metadata 715 * but dont have an ops for it 716 */ 717 pr_info_ratelimited("Unknown metaid %d dlen %d\n", 718 mtype, dlen); 719 qstats_overlimit_inc(this_cpu_ptr(ife->common.cpu_qstats)); 720 } 721 } 722 723 if (WARN_ON(tlv_data != ifehdr_end)) { 724 qstats_drop_inc(this_cpu_ptr(ife->common.cpu_qstats)); 725 return TC_ACT_SHOT; 726 } 727 728 skb->protocol = eth_type_trans(skb, skb->dev); 729 skb_reset_network_header(skb); 730 731 return action; 732 } 733 734 /*XXX: check if we can do this at install time instead of current 735 * send data path 736 **/ 737 static int ife_get_sz(struct sk_buff *skb, struct tcf_ife_info *ife) 738 { 739 struct tcf_meta_info *e, *n; 740 int tot_run_sz = 0, run_sz = 0; 741 742 list_for_each_entry_safe(e, n, &ife->metalist, metalist) { 743 if (e->ops->check_presence) { 744 run_sz = e->ops->check_presence(skb, e); 745 tot_run_sz += run_sz; 746 } 747 } 748 749 return tot_run_sz; 750 } 751 752 static int tcf_ife_encode(struct sk_buff *skb, const struct tc_action *a, 753 struct tcf_result *res, struct tcf_ife_params *p) 754 { 755 struct tcf_ife_info *ife = to_ife(a); 756 int action = ife->tcf_action; 757 struct ethhdr *oethh; /* outer ether header */ 758 struct tcf_meta_info *e; 759 /* 760 OUTERHDR:TOTMETALEN:{TLVHDR:Metadatum:TLVHDR..}:ORIGDATA 761 where ORIGDATA = original ethernet header ... 762 */ 763 u16 metalen = ife_get_sz(skb, ife); 764 int hdrm = metalen + skb->dev->hard_header_len + IFE_METAHDRLEN; 765 unsigned int skboff = 0; 766 int new_len = skb->len + hdrm; 767 bool exceed_mtu = false; 768 void *ife_meta; 769 int err = 0; 770 771 if (!skb_at_tc_ingress(skb)) { 772 if (new_len > skb->dev->mtu) 773 exceed_mtu = true; 774 } 775 776 bstats_cpu_update(this_cpu_ptr(ife->common.cpu_bstats), skb); 777 tcf_lastuse_update(&ife->tcf_tm); 778 779 if (!metalen) { /* no metadata to send */ 780 /* abuse overlimits to count when we allow packet 781 * with no metadata 782 */ 783 qstats_overlimit_inc(this_cpu_ptr(ife->common.cpu_qstats)); 784 return action; 785 } 786 /* could be stupid policy setup or mtu config 787 * so lets be conservative.. */ 788 if ((action == TC_ACT_SHOT) || exceed_mtu) { 789 qstats_drop_inc(this_cpu_ptr(ife->common.cpu_qstats)); 790 return TC_ACT_SHOT; 791 } 792 793 if (skb_at_tc_ingress(skb)) 794 skb_push(skb, skb->dev->hard_header_len); 795 796 ife_meta = ife_encode(skb, metalen); 797 798 spin_lock(&ife->tcf_lock); 799 800 /* XXX: we dont have a clever way of telling encode to 801 * not repeat some of the computations that are done by 802 * ops->presence_check... 803 */ 804 list_for_each_entry(e, &ife->metalist, metalist) { 805 if (e->ops->encode) { 806 err = e->ops->encode(skb, (void *)(ife_meta + skboff), 807 e); 808 } 809 if (err < 0) { 810 /* too corrupt to keep around if overwritten */ 811 spin_unlock(&ife->tcf_lock); 812 qstats_drop_inc(this_cpu_ptr(ife->common.cpu_qstats)); 813 return TC_ACT_SHOT; 814 } 815 skboff += err; 816 } 817 spin_unlock(&ife->tcf_lock); 818 oethh = (struct ethhdr *)skb->data; 819 820 if (!is_zero_ether_addr(p->eth_src)) 821 ether_addr_copy(oethh->h_source, p->eth_src); 822 if (!is_zero_ether_addr(p->eth_dst)) 823 ether_addr_copy(oethh->h_dest, p->eth_dst); 824 oethh->h_proto = htons(p->eth_type); 825 826 if (skb_at_tc_ingress(skb)) 827 skb_pull(skb, skb->dev->hard_header_len); 828 829 return action; 830 } 831 832 static int tcf_ife_act(struct sk_buff *skb, const struct tc_action *a, 833 struct tcf_result *res) 834 { 835 struct tcf_ife_info *ife = to_ife(a); 836 struct tcf_ife_params *p; 837 int ret; 838 839 p = rcu_dereference_bh(ife->params); 840 if (p->flags & IFE_ENCODE) { 841 ret = tcf_ife_encode(skb, a, res, p); 842 return ret; 843 } 844 845 return tcf_ife_decode(skb, a, res); 846 } 847 848 static int tcf_ife_walker(struct net *net, struct sk_buff *skb, 849 struct netlink_callback *cb, int type, 850 const struct tc_action_ops *ops, 851 struct netlink_ext_ack *extack) 852 { 853 struct tc_action_net *tn = net_generic(net, ife_net_id); 854 855 return tcf_generic_walker(tn, skb, cb, type, ops, extack); 856 } 857 858 static int tcf_ife_search(struct net *net, struct tc_action **a, u32 index) 859 { 860 struct tc_action_net *tn = net_generic(net, ife_net_id); 861 862 return tcf_idr_search(tn, a, index); 863 } 864 865 static struct tc_action_ops act_ife_ops = { 866 .kind = "ife", 867 .id = TCA_ID_IFE, 868 .owner = THIS_MODULE, 869 .act = tcf_ife_act, 870 .dump = tcf_ife_dump, 871 .cleanup = tcf_ife_cleanup, 872 .init = tcf_ife_init, 873 .walk = tcf_ife_walker, 874 .lookup = tcf_ife_search, 875 .size = sizeof(struct tcf_ife_info), 876 }; 877 878 static __net_init int ife_init_net(struct net *net) 879 { 880 struct tc_action_net *tn = net_generic(net, ife_net_id); 881 882 return tc_action_net_init(tn, &act_ife_ops); 883 } 884 885 static void __net_exit ife_exit_net(struct list_head *net_list) 886 { 887 tc_action_net_exit(net_list, ife_net_id); 888 } 889 890 static struct pernet_operations ife_net_ops = { 891 .init = ife_init_net, 892 .exit_batch = ife_exit_net, 893 .id = &ife_net_id, 894 .size = sizeof(struct tc_action_net), 895 }; 896 897 static int __init ife_init_module(void) 898 { 899 return tcf_register_action(&act_ife_ops, &ife_net_ops); 900 } 901 902 static void __exit ife_cleanup_module(void) 903 { 904 tcf_unregister_action(&act_ife_ops, &ife_net_ops); 905 } 906 907 module_init(ife_init_module); 908 module_exit(ife_cleanup_module); 909 910 MODULE_AUTHOR("Jamal Hadi Salim(2015)"); 911 MODULE_DESCRIPTION("Inter-FE LFB action"); 912 MODULE_LICENSE("GPL"); 913