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 <net/pkt_cls.h> 33 #include <uapi/linux/tc_act/tc_ife.h> 34 #include <net/tc_act/tc_ife.h> 35 #include <linux/etherdevice.h> 36 #include <net/ife.h> 37 38 static unsigned int ife_net_id; 39 static int max_metacnt = IFE_META_MAX + 1; 40 static struct tc_action_ops act_ife_ops; 41 42 static const struct nla_policy ife_policy[TCA_IFE_MAX + 1] = { 43 [TCA_IFE_PARMS] = { .len = sizeof(struct tc_ife)}, 44 [TCA_IFE_DMAC] = { .len = ETH_ALEN}, 45 [TCA_IFE_SMAC] = { .len = ETH_ALEN}, 46 [TCA_IFE_TYPE] = { .type = NLA_U16}, 47 }; 48 49 int ife_encode_meta_u16(u16 metaval, void *skbdata, struct tcf_meta_info *mi) 50 { 51 u16 edata = 0; 52 53 if (mi->metaval) 54 edata = *(u16 *)mi->metaval; 55 else if (metaval) 56 edata = metaval; 57 58 if (!edata) /* will not encode */ 59 return 0; 60 61 edata = htons(edata); 62 return ife_tlv_meta_encode(skbdata, mi->metaid, 2, &edata); 63 } 64 EXPORT_SYMBOL_GPL(ife_encode_meta_u16); 65 66 int ife_get_meta_u32(struct sk_buff *skb, struct tcf_meta_info *mi) 67 { 68 if (mi->metaval) 69 return nla_put_u32(skb, mi->metaid, *(u32 *)mi->metaval); 70 else 71 return nla_put(skb, mi->metaid, 0, NULL); 72 } 73 EXPORT_SYMBOL_GPL(ife_get_meta_u32); 74 75 int ife_check_meta_u32(u32 metaval, struct tcf_meta_info *mi) 76 { 77 if (metaval || mi->metaval) 78 return 8; /* T+L+V == 2+2+4 */ 79 80 return 0; 81 } 82 EXPORT_SYMBOL_GPL(ife_check_meta_u32); 83 84 int ife_check_meta_u16(u16 metaval, struct tcf_meta_info *mi) 85 { 86 if (metaval || mi->metaval) 87 return 8; /* T+L+(V) == 2+2+(2+2bytepad) */ 88 89 return 0; 90 } 91 EXPORT_SYMBOL_GPL(ife_check_meta_u16); 92 93 int ife_encode_meta_u32(u32 metaval, void *skbdata, struct tcf_meta_info *mi) 94 { 95 u32 edata = metaval; 96 97 if (mi->metaval) 98 edata = *(u32 *)mi->metaval; 99 else if (metaval) 100 edata = metaval; 101 102 if (!edata) /* will not encode */ 103 return 0; 104 105 edata = htonl(edata); 106 return ife_tlv_meta_encode(skbdata, mi->metaid, 4, &edata); 107 } 108 EXPORT_SYMBOL_GPL(ife_encode_meta_u32); 109 110 int ife_get_meta_u16(struct sk_buff *skb, struct tcf_meta_info *mi) 111 { 112 if (mi->metaval) 113 return nla_put_u16(skb, mi->metaid, *(u16 *)mi->metaval); 114 else 115 return nla_put(skb, mi->metaid, 0, NULL); 116 } 117 EXPORT_SYMBOL_GPL(ife_get_meta_u16); 118 119 int ife_alloc_meta_u32(struct tcf_meta_info *mi, void *metaval, gfp_t gfp) 120 { 121 mi->metaval = kmemdup(metaval, sizeof(u32), gfp); 122 if (!mi->metaval) 123 return -ENOMEM; 124 125 return 0; 126 } 127 EXPORT_SYMBOL_GPL(ife_alloc_meta_u32); 128 129 int ife_alloc_meta_u16(struct tcf_meta_info *mi, void *metaval, gfp_t gfp) 130 { 131 mi->metaval = kmemdup(metaval, sizeof(u16), gfp); 132 if (!mi->metaval) 133 return -ENOMEM; 134 135 return 0; 136 } 137 EXPORT_SYMBOL_GPL(ife_alloc_meta_u16); 138 139 void ife_release_meta_gen(struct tcf_meta_info *mi) 140 { 141 kfree(mi->metaval); 142 } 143 EXPORT_SYMBOL_GPL(ife_release_meta_gen); 144 145 int ife_validate_meta_u32(void *val, int len) 146 { 147 if (len == sizeof(u32)) 148 return 0; 149 150 return -EINVAL; 151 } 152 EXPORT_SYMBOL_GPL(ife_validate_meta_u32); 153 154 int ife_validate_meta_u16(void *val, int len) 155 { 156 /* length will not include padding */ 157 if (len == sizeof(u16)) 158 return 0; 159 160 return -EINVAL; 161 } 162 EXPORT_SYMBOL_GPL(ife_validate_meta_u16); 163 164 static LIST_HEAD(ifeoplist); 165 static DEFINE_RWLOCK(ife_mod_lock); 166 167 static struct tcf_meta_ops *find_ife_oplist(u16 metaid) 168 { 169 struct tcf_meta_ops *o; 170 171 read_lock(&ife_mod_lock); 172 list_for_each_entry(o, &ifeoplist, list) { 173 if (o->metaid == metaid) { 174 if (!try_module_get(o->owner)) 175 o = NULL; 176 read_unlock(&ife_mod_lock); 177 return o; 178 } 179 } 180 read_unlock(&ife_mod_lock); 181 182 return NULL; 183 } 184 185 int register_ife_op(struct tcf_meta_ops *mops) 186 { 187 struct tcf_meta_ops *m; 188 189 if (!mops->metaid || !mops->metatype || !mops->name || 190 !mops->check_presence || !mops->encode || !mops->decode || 191 !mops->get || !mops->alloc) 192 return -EINVAL; 193 194 write_lock(&ife_mod_lock); 195 196 list_for_each_entry(m, &ifeoplist, list) { 197 if (m->metaid == mops->metaid || 198 (strcmp(mops->name, m->name) == 0)) { 199 write_unlock(&ife_mod_lock); 200 return -EEXIST; 201 } 202 } 203 204 if (!mops->release) 205 mops->release = ife_release_meta_gen; 206 207 list_add_tail(&mops->list, &ifeoplist); 208 write_unlock(&ife_mod_lock); 209 return 0; 210 } 211 EXPORT_SYMBOL_GPL(unregister_ife_op); 212 213 int unregister_ife_op(struct tcf_meta_ops *mops) 214 { 215 struct tcf_meta_ops *m; 216 int err = -ENOENT; 217 218 write_lock(&ife_mod_lock); 219 list_for_each_entry(m, &ifeoplist, list) { 220 if (m->metaid == mops->metaid) { 221 list_del(&mops->list); 222 err = 0; 223 break; 224 } 225 } 226 write_unlock(&ife_mod_lock); 227 228 return err; 229 } 230 EXPORT_SYMBOL_GPL(register_ife_op); 231 232 static int ife_validate_metatype(struct tcf_meta_ops *ops, void *val, int len) 233 { 234 int ret = 0; 235 /* XXX: unfortunately cant use nla_policy at this point 236 * because a length of 0 is valid in the case of 237 * "allow". "use" semantics do enforce for proper 238 * length and i couldve use nla_policy but it makes it hard 239 * to use it just for that.. 240 */ 241 if (ops->validate) 242 return ops->validate(val, len); 243 244 if (ops->metatype == NLA_U32) 245 ret = ife_validate_meta_u32(val, len); 246 else if (ops->metatype == NLA_U16) 247 ret = ife_validate_meta_u16(val, len); 248 249 return ret; 250 } 251 252 #ifdef CONFIG_MODULES 253 static const char *ife_meta_id2name(u32 metaid) 254 { 255 switch (metaid) { 256 case IFE_META_SKBMARK: 257 return "skbmark"; 258 case IFE_META_PRIO: 259 return "skbprio"; 260 case IFE_META_TCINDEX: 261 return "tcindex"; 262 default: 263 return "unknown"; 264 } 265 } 266 #endif 267 268 /* called when adding new meta information 269 */ 270 static int load_metaops_and_vet(u32 metaid, void *val, int len, bool rtnl_held) 271 { 272 struct tcf_meta_ops *ops = find_ife_oplist(metaid); 273 int ret = 0; 274 275 if (!ops) { 276 ret = -ENOENT; 277 #ifdef CONFIG_MODULES 278 if (rtnl_held) 279 rtnl_unlock(); 280 request_module("ife-meta-%s", ife_meta_id2name(metaid)); 281 if (rtnl_held) 282 rtnl_lock(); 283 ops = find_ife_oplist(metaid); 284 #endif 285 } 286 287 if (ops) { 288 ret = 0; 289 if (len) 290 ret = ife_validate_metatype(ops, val, len); 291 292 module_put(ops->owner); 293 } 294 295 return ret; 296 } 297 298 /* called when adding new meta information 299 */ 300 static int __add_metainfo(const struct tcf_meta_ops *ops, 301 struct tcf_ife_info *ife, u32 metaid, void *metaval, 302 int len, bool atomic, bool exists) 303 { 304 struct tcf_meta_info *mi = NULL; 305 int ret = 0; 306 307 mi = kzalloc(sizeof(*mi), atomic ? GFP_ATOMIC : GFP_KERNEL); 308 if (!mi) 309 return -ENOMEM; 310 311 mi->metaid = metaid; 312 mi->ops = ops; 313 if (len > 0) { 314 ret = ops->alloc(mi, metaval, atomic ? GFP_ATOMIC : GFP_KERNEL); 315 if (ret != 0) { 316 kfree(mi); 317 return ret; 318 } 319 } 320 321 if (exists) 322 spin_lock_bh(&ife->tcf_lock); 323 list_add_tail(&mi->metalist, &ife->metalist); 324 if (exists) 325 spin_unlock_bh(&ife->tcf_lock); 326 327 return ret; 328 } 329 330 static int add_metainfo_and_get_ops(const struct tcf_meta_ops *ops, 331 struct tcf_ife_info *ife, u32 metaid, 332 bool exists) 333 { 334 int ret; 335 336 if (!try_module_get(ops->owner)) 337 return -ENOENT; 338 ret = __add_metainfo(ops, ife, metaid, NULL, 0, true, exists); 339 if (ret) 340 module_put(ops->owner); 341 return ret; 342 } 343 344 static int add_metainfo(struct tcf_ife_info *ife, u32 metaid, void *metaval, 345 int len, bool exists) 346 { 347 const struct tcf_meta_ops *ops = find_ife_oplist(metaid); 348 int ret; 349 350 if (!ops) 351 return -ENOENT; 352 ret = __add_metainfo(ops, ife, metaid, metaval, len, false, exists); 353 if (ret) 354 /*put back what find_ife_oplist took */ 355 module_put(ops->owner); 356 return ret; 357 } 358 359 static int use_all_metadata(struct tcf_ife_info *ife, bool exists) 360 { 361 struct tcf_meta_ops *o; 362 int rc = 0; 363 int installed = 0; 364 365 read_lock(&ife_mod_lock); 366 list_for_each_entry(o, &ifeoplist, list) { 367 rc = add_metainfo_and_get_ops(o, ife, o->metaid, exists); 368 if (rc == 0) 369 installed += 1; 370 } 371 read_unlock(&ife_mod_lock); 372 373 if (installed) 374 return 0; 375 else 376 return -EINVAL; 377 } 378 379 static int dump_metalist(struct sk_buff *skb, struct tcf_ife_info *ife) 380 { 381 struct tcf_meta_info *e; 382 struct nlattr *nest; 383 unsigned char *b = skb_tail_pointer(skb); 384 int total_encoded = 0; 385 386 /*can only happen on decode */ 387 if (list_empty(&ife->metalist)) 388 return 0; 389 390 nest = nla_nest_start(skb, TCA_IFE_METALST); 391 if (!nest) 392 goto out_nlmsg_trim; 393 394 list_for_each_entry(e, &ife->metalist, metalist) { 395 if (!e->ops->get(skb, e)) 396 total_encoded += 1; 397 } 398 399 if (!total_encoded) 400 goto out_nlmsg_trim; 401 402 nla_nest_end(skb, nest); 403 404 return 0; 405 406 out_nlmsg_trim: 407 nlmsg_trim(skb, b); 408 return -1; 409 } 410 411 /* under ife->tcf_lock */ 412 static void _tcf_ife_cleanup(struct tc_action *a) 413 { 414 struct tcf_ife_info *ife = to_ife(a); 415 struct tcf_meta_info *e, *n; 416 417 list_for_each_entry_safe(e, n, &ife->metalist, metalist) { 418 list_del(&e->metalist); 419 if (e->metaval) { 420 if (e->ops->release) 421 e->ops->release(e); 422 else 423 kfree(e->metaval); 424 } 425 module_put(e->ops->owner); 426 kfree(e); 427 } 428 } 429 430 static void tcf_ife_cleanup(struct tc_action *a) 431 { 432 struct tcf_ife_info *ife = to_ife(a); 433 struct tcf_ife_params *p; 434 435 spin_lock_bh(&ife->tcf_lock); 436 _tcf_ife_cleanup(a); 437 spin_unlock_bh(&ife->tcf_lock); 438 439 p = rcu_dereference_protected(ife->params, 1); 440 if (p) 441 kfree_rcu(p, rcu); 442 } 443 444 static int populate_metalist(struct tcf_ife_info *ife, struct nlattr **tb, 445 bool exists, bool rtnl_held) 446 { 447 int len = 0; 448 int rc = 0; 449 int i = 0; 450 void *val; 451 452 for (i = 1; i < max_metacnt; i++) { 453 if (tb[i]) { 454 val = nla_data(tb[i]); 455 len = nla_len(tb[i]); 456 457 rc = load_metaops_and_vet(i, val, len, rtnl_held); 458 if (rc != 0) 459 return rc; 460 461 rc = add_metainfo(ife, i, val, len, exists); 462 if (rc) 463 return rc; 464 } 465 } 466 467 return rc; 468 } 469 470 static int tcf_ife_init(struct net *net, struct nlattr *nla, 471 struct nlattr *est, struct tc_action **a, 472 int ovr, int bind, bool rtnl_held, 473 struct tcf_proto *tp, struct netlink_ext_ack *extack) 474 { 475 struct tc_action_net *tn = net_generic(net, ife_net_id); 476 struct nlattr *tb[TCA_IFE_MAX + 1]; 477 struct nlattr *tb2[IFE_META_MAX + 1]; 478 struct tcf_chain *goto_ch = NULL; 479 struct tcf_ife_params *p; 480 struct tcf_ife_info *ife; 481 u16 ife_type = ETH_P_IFE; 482 struct tc_ife *parm; 483 u8 *daddr = NULL; 484 u8 *saddr = NULL; 485 bool exists = false; 486 int ret = 0; 487 int err; 488 489 err = nla_parse_nested(tb, TCA_IFE_MAX, nla, ife_policy, NULL); 490 if (err < 0) 491 return err; 492 493 if (!tb[TCA_IFE_PARMS]) 494 return -EINVAL; 495 496 parm = nla_data(tb[TCA_IFE_PARMS]); 497 498 /* IFE_DECODE is 0 and indicates the opposite of IFE_ENCODE because 499 * they cannot run as the same time. Check on all other values which 500 * are not supported right now. 501 */ 502 if (parm->flags & ~IFE_ENCODE) 503 return -EINVAL; 504 505 p = kzalloc(sizeof(*p), GFP_KERNEL); 506 if (!p) 507 return -ENOMEM; 508 509 err = tcf_idr_check_alloc(tn, &parm->index, a, bind); 510 if (err < 0) { 511 kfree(p); 512 return err; 513 } 514 exists = err; 515 if (exists && bind) { 516 kfree(p); 517 return 0; 518 } 519 520 if (!exists) { 521 ret = tcf_idr_create(tn, parm->index, est, a, &act_ife_ops, 522 bind, true); 523 if (ret) { 524 tcf_idr_cleanup(tn, parm->index); 525 kfree(p); 526 return ret; 527 } 528 ret = ACT_P_CREATED; 529 } else if (!ovr) { 530 tcf_idr_release(*a, bind); 531 kfree(p); 532 return -EEXIST; 533 } 534 535 ife = to_ife(*a); 536 err = tcf_action_check_ctrlact(parm->action, tp, &goto_ch, extack); 537 if (err < 0) 538 goto release_idr; 539 540 p->flags = parm->flags; 541 542 if (parm->flags & IFE_ENCODE) { 543 if (tb[TCA_IFE_TYPE]) 544 ife_type = nla_get_u16(tb[TCA_IFE_TYPE]); 545 if (tb[TCA_IFE_DMAC]) 546 daddr = nla_data(tb[TCA_IFE_DMAC]); 547 if (tb[TCA_IFE_SMAC]) 548 saddr = nla_data(tb[TCA_IFE_SMAC]); 549 } 550 551 if (parm->flags & IFE_ENCODE) { 552 if (daddr) 553 ether_addr_copy(p->eth_dst, daddr); 554 else 555 eth_zero_addr(p->eth_dst); 556 557 if (saddr) 558 ether_addr_copy(p->eth_src, saddr); 559 else 560 eth_zero_addr(p->eth_src); 561 562 p->eth_type = ife_type; 563 } 564 565 566 if (ret == ACT_P_CREATED) 567 INIT_LIST_HEAD(&ife->metalist); 568 569 if (tb[TCA_IFE_METALST]) { 570 err = nla_parse_nested(tb2, IFE_META_MAX, tb[TCA_IFE_METALST], 571 NULL, NULL); 572 if (err) 573 goto metadata_parse_err; 574 err = populate_metalist(ife, tb2, exists, rtnl_held); 575 if (err) 576 goto metadata_parse_err; 577 578 } else { 579 /* if no passed metadata allow list or passed allow-all 580 * then here we process by adding as many supported metadatum 581 * as we can. You better have at least one else we are 582 * going to bail out 583 */ 584 err = use_all_metadata(ife, exists); 585 if (err) 586 goto metadata_parse_err; 587 } 588 589 if (exists) 590 spin_lock_bh(&ife->tcf_lock); 591 /* protected by tcf_lock when modifying existing action */ 592 goto_ch = tcf_action_set_ctrlact(*a, parm->action, goto_ch); 593 rcu_swap_protected(ife->params, p, 1); 594 595 if (exists) 596 spin_unlock_bh(&ife->tcf_lock); 597 if (goto_ch) 598 tcf_chain_put_by_act(goto_ch); 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 metadata_parse_err: 607 if (goto_ch) 608 tcf_chain_put_by_act(goto_ch); 609 release_idr: 610 kfree(p); 611 tcf_idr_release(*a, bind); 612 return err; 613 } 614 615 static int tcf_ife_dump(struct sk_buff *skb, struct tc_action *a, int bind, 616 int ref) 617 { 618 unsigned char *b = skb_tail_pointer(skb); 619 struct tcf_ife_info *ife = to_ife(a); 620 struct tcf_ife_params *p; 621 struct tc_ife opt = { 622 .index = ife->tcf_index, 623 .refcnt = refcount_read(&ife->tcf_refcnt) - ref, 624 .bindcnt = atomic_read(&ife->tcf_bindcnt) - bind, 625 }; 626 struct tcf_t t; 627 628 spin_lock_bh(&ife->tcf_lock); 629 opt.action = ife->tcf_action; 630 p = rcu_dereference_protected(ife->params, 631 lockdep_is_held(&ife->tcf_lock)); 632 opt.flags = p->flags; 633 634 if (nla_put(skb, TCA_IFE_PARMS, sizeof(opt), &opt)) 635 goto nla_put_failure; 636 637 tcf_tm_dump(&t, &ife->tcf_tm); 638 if (nla_put_64bit(skb, TCA_IFE_TM, sizeof(t), &t, TCA_IFE_PAD)) 639 goto nla_put_failure; 640 641 if (!is_zero_ether_addr(p->eth_dst)) { 642 if (nla_put(skb, TCA_IFE_DMAC, ETH_ALEN, p->eth_dst)) 643 goto nla_put_failure; 644 } 645 646 if (!is_zero_ether_addr(p->eth_src)) { 647 if (nla_put(skb, TCA_IFE_SMAC, ETH_ALEN, p->eth_src)) 648 goto nla_put_failure; 649 } 650 651 if (nla_put(skb, TCA_IFE_TYPE, 2, &p->eth_type)) 652 goto nla_put_failure; 653 654 if (dump_metalist(skb, ife)) { 655 /*ignore failure to dump metalist */ 656 pr_info("Failed to dump metalist\n"); 657 } 658 659 spin_unlock_bh(&ife->tcf_lock); 660 return skb->len; 661 662 nla_put_failure: 663 spin_unlock_bh(&ife->tcf_lock); 664 nlmsg_trim(skb, b); 665 return -1; 666 } 667 668 static int find_decode_metaid(struct sk_buff *skb, struct tcf_ife_info *ife, 669 u16 metaid, u16 mlen, void *mdata) 670 { 671 struct tcf_meta_info *e; 672 673 /* XXX: use hash to speed up */ 674 list_for_each_entry(e, &ife->metalist, metalist) { 675 if (metaid == e->metaid) { 676 if (e->ops) { 677 /* We check for decode presence already */ 678 return e->ops->decode(skb, mdata, mlen); 679 } 680 } 681 } 682 683 return -ENOENT; 684 } 685 686 static int tcf_ife_decode(struct sk_buff *skb, const struct tc_action *a, 687 struct tcf_result *res) 688 { 689 struct tcf_ife_info *ife = to_ife(a); 690 int action = ife->tcf_action; 691 u8 *ifehdr_end; 692 u8 *tlv_data; 693 u16 metalen; 694 695 bstats_cpu_update(this_cpu_ptr(ife->common.cpu_bstats), skb); 696 tcf_lastuse_update(&ife->tcf_tm); 697 698 if (skb_at_tc_ingress(skb)) 699 skb_push(skb, skb->dev->hard_header_len); 700 701 tlv_data = ife_decode(skb, &metalen); 702 if (unlikely(!tlv_data)) { 703 qstats_drop_inc(this_cpu_ptr(ife->common.cpu_qstats)); 704 return TC_ACT_SHOT; 705 } 706 707 ifehdr_end = tlv_data + metalen; 708 for (; tlv_data < ifehdr_end; tlv_data = ife_tlv_meta_next(tlv_data)) { 709 u8 *curr_data; 710 u16 mtype; 711 u16 dlen; 712 713 curr_data = ife_tlv_meta_decode(tlv_data, ifehdr_end, &mtype, 714 &dlen, NULL); 715 if (!curr_data) { 716 qstats_drop_inc(this_cpu_ptr(ife->common.cpu_qstats)); 717 return TC_ACT_SHOT; 718 } 719 720 if (find_decode_metaid(skb, ife, mtype, dlen, curr_data)) { 721 /* abuse overlimits to count when we receive metadata 722 * but dont have an ops for it 723 */ 724 pr_info_ratelimited("Unknown metaid %d dlen %d\n", 725 mtype, dlen); 726 qstats_overlimit_inc(this_cpu_ptr(ife->common.cpu_qstats)); 727 } 728 } 729 730 if (WARN_ON(tlv_data != ifehdr_end)) { 731 qstats_drop_inc(this_cpu_ptr(ife->common.cpu_qstats)); 732 return TC_ACT_SHOT; 733 } 734 735 skb->protocol = eth_type_trans(skb, skb->dev); 736 skb_reset_network_header(skb); 737 738 return action; 739 } 740 741 /*XXX: check if we can do this at install time instead of current 742 * send data path 743 **/ 744 static int ife_get_sz(struct sk_buff *skb, struct tcf_ife_info *ife) 745 { 746 struct tcf_meta_info *e, *n; 747 int tot_run_sz = 0, run_sz = 0; 748 749 list_for_each_entry_safe(e, n, &ife->metalist, metalist) { 750 if (e->ops->check_presence) { 751 run_sz = e->ops->check_presence(skb, e); 752 tot_run_sz += run_sz; 753 } 754 } 755 756 return tot_run_sz; 757 } 758 759 static int tcf_ife_encode(struct sk_buff *skb, const struct tc_action *a, 760 struct tcf_result *res, struct tcf_ife_params *p) 761 { 762 struct tcf_ife_info *ife = to_ife(a); 763 int action = ife->tcf_action; 764 struct ethhdr *oethh; /* outer ether header */ 765 struct tcf_meta_info *e; 766 /* 767 OUTERHDR:TOTMETALEN:{TLVHDR:Metadatum:TLVHDR..}:ORIGDATA 768 where ORIGDATA = original ethernet header ... 769 */ 770 u16 metalen = ife_get_sz(skb, ife); 771 int hdrm = metalen + skb->dev->hard_header_len + IFE_METAHDRLEN; 772 unsigned int skboff = 0; 773 int new_len = skb->len + hdrm; 774 bool exceed_mtu = false; 775 void *ife_meta; 776 int err = 0; 777 778 if (!skb_at_tc_ingress(skb)) { 779 if (new_len > skb->dev->mtu) 780 exceed_mtu = true; 781 } 782 783 bstats_cpu_update(this_cpu_ptr(ife->common.cpu_bstats), skb); 784 tcf_lastuse_update(&ife->tcf_tm); 785 786 if (!metalen) { /* no metadata to send */ 787 /* abuse overlimits to count when we allow packet 788 * with no metadata 789 */ 790 qstats_overlimit_inc(this_cpu_ptr(ife->common.cpu_qstats)); 791 return action; 792 } 793 /* could be stupid policy setup or mtu config 794 * so lets be conservative.. */ 795 if ((action == TC_ACT_SHOT) || exceed_mtu) { 796 qstats_drop_inc(this_cpu_ptr(ife->common.cpu_qstats)); 797 return TC_ACT_SHOT; 798 } 799 800 if (skb_at_tc_ingress(skb)) 801 skb_push(skb, skb->dev->hard_header_len); 802 803 ife_meta = ife_encode(skb, metalen); 804 805 spin_lock(&ife->tcf_lock); 806 807 /* XXX: we dont have a clever way of telling encode to 808 * not repeat some of the computations that are done by 809 * ops->presence_check... 810 */ 811 list_for_each_entry(e, &ife->metalist, metalist) { 812 if (e->ops->encode) { 813 err = e->ops->encode(skb, (void *)(ife_meta + skboff), 814 e); 815 } 816 if (err < 0) { 817 /* too corrupt to keep around if overwritten */ 818 spin_unlock(&ife->tcf_lock); 819 qstats_drop_inc(this_cpu_ptr(ife->common.cpu_qstats)); 820 return TC_ACT_SHOT; 821 } 822 skboff += err; 823 } 824 spin_unlock(&ife->tcf_lock); 825 oethh = (struct ethhdr *)skb->data; 826 827 if (!is_zero_ether_addr(p->eth_src)) 828 ether_addr_copy(oethh->h_source, p->eth_src); 829 if (!is_zero_ether_addr(p->eth_dst)) 830 ether_addr_copy(oethh->h_dest, p->eth_dst); 831 oethh->h_proto = htons(p->eth_type); 832 833 if (skb_at_tc_ingress(skb)) 834 skb_pull(skb, skb->dev->hard_header_len); 835 836 return action; 837 } 838 839 static int tcf_ife_act(struct sk_buff *skb, const struct tc_action *a, 840 struct tcf_result *res) 841 { 842 struct tcf_ife_info *ife = to_ife(a); 843 struct tcf_ife_params *p; 844 int ret; 845 846 p = rcu_dereference_bh(ife->params); 847 if (p->flags & IFE_ENCODE) { 848 ret = tcf_ife_encode(skb, a, res, p); 849 return ret; 850 } 851 852 return tcf_ife_decode(skb, a, res); 853 } 854 855 static int tcf_ife_walker(struct net *net, struct sk_buff *skb, 856 struct netlink_callback *cb, int type, 857 const struct tc_action_ops *ops, 858 struct netlink_ext_ack *extack) 859 { 860 struct tc_action_net *tn = net_generic(net, ife_net_id); 861 862 return tcf_generic_walker(tn, skb, cb, type, ops, extack); 863 } 864 865 static int tcf_ife_search(struct net *net, struct tc_action **a, u32 index) 866 { 867 struct tc_action_net *tn = net_generic(net, ife_net_id); 868 869 return tcf_idr_search(tn, a, index); 870 } 871 872 static struct tc_action_ops act_ife_ops = { 873 .kind = "ife", 874 .id = TCA_ID_IFE, 875 .owner = THIS_MODULE, 876 .act = tcf_ife_act, 877 .dump = tcf_ife_dump, 878 .cleanup = tcf_ife_cleanup, 879 .init = tcf_ife_init, 880 .walk = tcf_ife_walker, 881 .lookup = tcf_ife_search, 882 .size = sizeof(struct tcf_ife_info), 883 }; 884 885 static __net_init int ife_init_net(struct net *net) 886 { 887 struct tc_action_net *tn = net_generic(net, ife_net_id); 888 889 return tc_action_net_init(tn, &act_ife_ops); 890 } 891 892 static void __net_exit ife_exit_net(struct list_head *net_list) 893 { 894 tc_action_net_exit(net_list, ife_net_id); 895 } 896 897 static struct pernet_operations ife_net_ops = { 898 .init = ife_init_net, 899 .exit_batch = ife_exit_net, 900 .id = &ife_net_id, 901 .size = sizeof(struct tc_action_net), 902 }; 903 904 static int __init ife_init_module(void) 905 { 906 return tcf_register_action(&act_ife_ops, &ife_net_ops); 907 } 908 909 static void __exit ife_cleanup_module(void) 910 { 911 tcf_unregister_action(&act_ife_ops, &ife_net_ops); 912 } 913 914 module_init(ife_init_module); 915 module_exit(ife_cleanup_module); 916 917 MODULE_AUTHOR("Jamal Hadi Salim(2015)"); 918 MODULE_DESCRIPTION("Inter-FE LFB action"); 919 MODULE_LICENSE("GPL"); 920