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 if (p) 419 kfree_rcu(p, rcu); 420 } 421 422 /* under ife->tcf_lock for existing action */ 423 static int populate_metalist(struct tcf_ife_info *ife, struct nlattr **tb, 424 bool exists) 425 { 426 int len = 0; 427 int rc = 0; 428 int i = 0; 429 void *val; 430 431 for (i = 1; i < max_metacnt; i++) { 432 if (tb[i]) { 433 val = nla_data(tb[i]); 434 len = nla_len(tb[i]); 435 436 rc = load_metaops_and_vet(ife, i, val, len, exists); 437 if (rc != 0) 438 return rc; 439 440 rc = add_metainfo(ife, i, val, len, exists); 441 if (rc) 442 return rc; 443 } 444 } 445 446 return rc; 447 } 448 449 static int tcf_ife_init(struct net *net, struct nlattr *nla, 450 struct nlattr *est, struct tc_action **a, 451 int ovr, int bind, struct netlink_ext_ack *extack) 452 { 453 struct tc_action_net *tn = net_generic(net, ife_net_id); 454 struct nlattr *tb[TCA_IFE_MAX + 1]; 455 struct nlattr *tb2[IFE_META_MAX + 1]; 456 struct tcf_ife_params *p, *p_old; 457 struct tcf_ife_info *ife; 458 u16 ife_type = ETH_P_IFE; 459 struct tc_ife *parm; 460 u8 *daddr = NULL; 461 u8 *saddr = NULL; 462 bool exists = false; 463 int ret = 0; 464 int err; 465 466 err = nla_parse_nested(tb, TCA_IFE_MAX, nla, ife_policy, NULL); 467 if (err < 0) 468 return err; 469 470 if (!tb[TCA_IFE_PARMS]) 471 return -EINVAL; 472 473 parm = nla_data(tb[TCA_IFE_PARMS]); 474 475 /* IFE_DECODE is 0 and indicates the opposite of IFE_ENCODE because 476 * they cannot run as the same time. Check on all other values which 477 * are not supported right now. 478 */ 479 if (parm->flags & ~IFE_ENCODE) 480 return -EINVAL; 481 482 p = kzalloc(sizeof(*p), GFP_KERNEL); 483 if (!p) 484 return -ENOMEM; 485 486 exists = tcf_idr_check(tn, parm->index, a, bind); 487 if (exists && bind) { 488 kfree(p); 489 return 0; 490 } 491 492 if (!exists) { 493 ret = tcf_idr_create(tn, parm->index, est, a, &act_ife_ops, 494 bind, true); 495 if (ret) { 496 kfree(p); 497 return ret; 498 } 499 ret = ACT_P_CREATED; 500 } else { 501 tcf_idr_release(*a, bind); 502 if (!ovr) { 503 kfree(p); 504 return -EEXIST; 505 } 506 } 507 508 ife = to_ife(*a); 509 p->flags = parm->flags; 510 511 if (parm->flags & IFE_ENCODE) { 512 if (tb[TCA_IFE_TYPE]) 513 ife_type = nla_get_u16(tb[TCA_IFE_TYPE]); 514 if (tb[TCA_IFE_DMAC]) 515 daddr = nla_data(tb[TCA_IFE_DMAC]); 516 if (tb[TCA_IFE_SMAC]) 517 saddr = nla_data(tb[TCA_IFE_SMAC]); 518 } 519 520 if (parm->flags & IFE_ENCODE) { 521 if (daddr) 522 ether_addr_copy(p->eth_dst, daddr); 523 else 524 eth_zero_addr(p->eth_dst); 525 526 if (saddr) 527 ether_addr_copy(p->eth_src, saddr); 528 else 529 eth_zero_addr(p->eth_src); 530 531 p->eth_type = ife_type; 532 } 533 534 if (exists) 535 spin_lock_bh(&ife->tcf_lock); 536 537 if (ret == ACT_P_CREATED) 538 INIT_LIST_HEAD(&ife->metalist); 539 540 if (tb[TCA_IFE_METALST]) { 541 err = nla_parse_nested(tb2, IFE_META_MAX, tb[TCA_IFE_METALST], 542 NULL, NULL); 543 if (err) { 544 metadata_parse_err: 545 if (ret == ACT_P_CREATED) 546 tcf_idr_release(*a, bind); 547 548 if (exists) 549 spin_unlock_bh(&ife->tcf_lock); 550 kfree(p); 551 return err; 552 } 553 554 err = populate_metalist(ife, tb2, exists); 555 if (err) 556 goto metadata_parse_err; 557 558 } else { 559 /* if no passed metadata allow list or passed allow-all 560 * then here we process by adding as many supported metadatum 561 * as we can. You better have at least one else we are 562 * going to bail out 563 */ 564 err = use_all_metadata(ife); 565 if (err) { 566 if (ret == ACT_P_CREATED) 567 tcf_idr_release(*a, bind); 568 569 if (exists) 570 spin_unlock_bh(&ife->tcf_lock); 571 kfree(p); 572 return err; 573 } 574 } 575 576 ife->tcf_action = parm->action; 577 if (exists) 578 spin_unlock_bh(&ife->tcf_lock); 579 580 p_old = rtnl_dereference(ife->params); 581 rcu_assign_pointer(ife->params, p); 582 if (p_old) 583 kfree_rcu(p_old, rcu); 584 585 if (ret == ACT_P_CREATED) 586 tcf_idr_insert(tn, *a); 587 588 return ret; 589 } 590 591 static int tcf_ife_dump(struct sk_buff *skb, struct tc_action *a, int bind, 592 int ref) 593 { 594 unsigned char *b = skb_tail_pointer(skb); 595 struct tcf_ife_info *ife = to_ife(a); 596 struct tcf_ife_params *p = rtnl_dereference(ife->params); 597 struct tc_ife opt = { 598 .index = ife->tcf_index, 599 .refcnt = refcount_read(&ife->tcf_refcnt) - ref, 600 .bindcnt = atomic_read(&ife->tcf_bindcnt) - bind, 601 .action = ife->tcf_action, 602 .flags = p->flags, 603 }; 604 struct tcf_t t; 605 606 if (nla_put(skb, TCA_IFE_PARMS, sizeof(opt), &opt)) 607 goto nla_put_failure; 608 609 tcf_tm_dump(&t, &ife->tcf_tm); 610 if (nla_put_64bit(skb, TCA_IFE_TM, sizeof(t), &t, TCA_IFE_PAD)) 611 goto nla_put_failure; 612 613 if (!is_zero_ether_addr(p->eth_dst)) { 614 if (nla_put(skb, TCA_IFE_DMAC, ETH_ALEN, p->eth_dst)) 615 goto nla_put_failure; 616 } 617 618 if (!is_zero_ether_addr(p->eth_src)) { 619 if (nla_put(skb, TCA_IFE_SMAC, ETH_ALEN, p->eth_src)) 620 goto nla_put_failure; 621 } 622 623 if (nla_put(skb, TCA_IFE_TYPE, 2, &p->eth_type)) 624 goto nla_put_failure; 625 626 if (dump_metalist(skb, ife)) { 627 /*ignore failure to dump metalist */ 628 pr_info("Failed to dump metalist\n"); 629 } 630 631 return skb->len; 632 633 nla_put_failure: 634 nlmsg_trim(skb, b); 635 return -1; 636 } 637 638 static int find_decode_metaid(struct sk_buff *skb, struct tcf_ife_info *ife, 639 u16 metaid, u16 mlen, void *mdata) 640 { 641 struct tcf_meta_info *e; 642 643 /* XXX: use hash to speed up */ 644 list_for_each_entry(e, &ife->metalist, metalist) { 645 if (metaid == e->metaid) { 646 if (e->ops) { 647 /* We check for decode presence already */ 648 return e->ops->decode(skb, mdata, mlen); 649 } 650 } 651 } 652 653 return -ENOENT; 654 } 655 656 static int tcf_ife_decode(struct sk_buff *skb, const struct tc_action *a, 657 struct tcf_result *res) 658 { 659 struct tcf_ife_info *ife = to_ife(a); 660 int action = ife->tcf_action; 661 u8 *ifehdr_end; 662 u8 *tlv_data; 663 u16 metalen; 664 665 bstats_cpu_update(this_cpu_ptr(ife->common.cpu_bstats), skb); 666 tcf_lastuse_update(&ife->tcf_tm); 667 668 if (skb_at_tc_ingress(skb)) 669 skb_push(skb, skb->dev->hard_header_len); 670 671 tlv_data = ife_decode(skb, &metalen); 672 if (unlikely(!tlv_data)) { 673 qstats_drop_inc(this_cpu_ptr(ife->common.cpu_qstats)); 674 return TC_ACT_SHOT; 675 } 676 677 ifehdr_end = tlv_data + metalen; 678 for (; tlv_data < ifehdr_end; tlv_data = ife_tlv_meta_next(tlv_data)) { 679 u8 *curr_data; 680 u16 mtype; 681 u16 dlen; 682 683 curr_data = ife_tlv_meta_decode(tlv_data, ifehdr_end, &mtype, 684 &dlen, NULL); 685 if (!curr_data) { 686 qstats_drop_inc(this_cpu_ptr(ife->common.cpu_qstats)); 687 return TC_ACT_SHOT; 688 } 689 690 if (find_decode_metaid(skb, ife, mtype, dlen, curr_data)) { 691 /* abuse overlimits to count when we receive metadata 692 * but dont have an ops for it 693 */ 694 pr_info_ratelimited("Unknown metaid %d dlen %d\n", 695 mtype, dlen); 696 qstats_overlimit_inc(this_cpu_ptr(ife->common.cpu_qstats)); 697 } 698 } 699 700 if (WARN_ON(tlv_data != ifehdr_end)) { 701 qstats_drop_inc(this_cpu_ptr(ife->common.cpu_qstats)); 702 return TC_ACT_SHOT; 703 } 704 705 skb->protocol = eth_type_trans(skb, skb->dev); 706 skb_reset_network_header(skb); 707 708 return action; 709 } 710 711 /*XXX: check if we can do this at install time instead of current 712 * send data path 713 **/ 714 static int ife_get_sz(struct sk_buff *skb, struct tcf_ife_info *ife) 715 { 716 struct tcf_meta_info *e, *n; 717 int tot_run_sz = 0, run_sz = 0; 718 719 list_for_each_entry_safe(e, n, &ife->metalist, metalist) { 720 if (e->ops->check_presence) { 721 run_sz = e->ops->check_presence(skb, e); 722 tot_run_sz += run_sz; 723 } 724 } 725 726 return tot_run_sz; 727 } 728 729 static int tcf_ife_encode(struct sk_buff *skb, const struct tc_action *a, 730 struct tcf_result *res, struct tcf_ife_params *p) 731 { 732 struct tcf_ife_info *ife = to_ife(a); 733 int action = ife->tcf_action; 734 struct ethhdr *oethh; /* outer ether header */ 735 struct tcf_meta_info *e; 736 /* 737 OUTERHDR:TOTMETALEN:{TLVHDR:Metadatum:TLVHDR..}:ORIGDATA 738 where ORIGDATA = original ethernet header ... 739 */ 740 u16 metalen = ife_get_sz(skb, ife); 741 int hdrm = metalen + skb->dev->hard_header_len + IFE_METAHDRLEN; 742 unsigned int skboff = 0; 743 int new_len = skb->len + hdrm; 744 bool exceed_mtu = false; 745 void *ife_meta; 746 int err = 0; 747 748 if (!skb_at_tc_ingress(skb)) { 749 if (new_len > skb->dev->mtu) 750 exceed_mtu = true; 751 } 752 753 bstats_cpu_update(this_cpu_ptr(ife->common.cpu_bstats), skb); 754 tcf_lastuse_update(&ife->tcf_tm); 755 756 if (!metalen) { /* no metadata to send */ 757 /* abuse overlimits to count when we allow packet 758 * with no metadata 759 */ 760 qstats_overlimit_inc(this_cpu_ptr(ife->common.cpu_qstats)); 761 return action; 762 } 763 /* could be stupid policy setup or mtu config 764 * so lets be conservative.. */ 765 if ((action == TC_ACT_SHOT) || exceed_mtu) { 766 qstats_drop_inc(this_cpu_ptr(ife->common.cpu_qstats)); 767 return TC_ACT_SHOT; 768 } 769 770 if (skb_at_tc_ingress(skb)) 771 skb_push(skb, skb->dev->hard_header_len); 772 773 ife_meta = ife_encode(skb, metalen); 774 775 spin_lock(&ife->tcf_lock); 776 777 /* XXX: we dont have a clever way of telling encode to 778 * not repeat some of the computations that are done by 779 * ops->presence_check... 780 */ 781 list_for_each_entry(e, &ife->metalist, metalist) { 782 if (e->ops->encode) { 783 err = e->ops->encode(skb, (void *)(ife_meta + skboff), 784 e); 785 } 786 if (err < 0) { 787 /* too corrupt to keep around if overwritten */ 788 spin_unlock(&ife->tcf_lock); 789 qstats_drop_inc(this_cpu_ptr(ife->common.cpu_qstats)); 790 return TC_ACT_SHOT; 791 } 792 skboff += err; 793 } 794 spin_unlock(&ife->tcf_lock); 795 oethh = (struct ethhdr *)skb->data; 796 797 if (!is_zero_ether_addr(p->eth_src)) 798 ether_addr_copy(oethh->h_source, p->eth_src); 799 if (!is_zero_ether_addr(p->eth_dst)) 800 ether_addr_copy(oethh->h_dest, p->eth_dst); 801 oethh->h_proto = htons(p->eth_type); 802 803 if (skb_at_tc_ingress(skb)) 804 skb_pull(skb, skb->dev->hard_header_len); 805 806 return action; 807 } 808 809 static int tcf_ife_act(struct sk_buff *skb, const struct tc_action *a, 810 struct tcf_result *res) 811 { 812 struct tcf_ife_info *ife = to_ife(a); 813 struct tcf_ife_params *p; 814 int ret; 815 816 rcu_read_lock(); 817 p = rcu_dereference(ife->params); 818 if (p->flags & IFE_ENCODE) { 819 ret = tcf_ife_encode(skb, a, res, p); 820 rcu_read_unlock(); 821 return ret; 822 } 823 rcu_read_unlock(); 824 825 return tcf_ife_decode(skb, a, res); 826 } 827 828 static int tcf_ife_walker(struct net *net, struct sk_buff *skb, 829 struct netlink_callback *cb, int type, 830 const struct tc_action_ops *ops, 831 struct netlink_ext_ack *extack) 832 { 833 struct tc_action_net *tn = net_generic(net, ife_net_id); 834 835 return tcf_generic_walker(tn, skb, cb, type, ops, extack); 836 } 837 838 static int tcf_ife_search(struct net *net, struct tc_action **a, u32 index, 839 struct netlink_ext_ack *extack) 840 { 841 struct tc_action_net *tn = net_generic(net, ife_net_id); 842 843 return tcf_idr_search(tn, a, index); 844 } 845 846 static struct tc_action_ops act_ife_ops = { 847 .kind = "ife", 848 .type = TCA_ACT_IFE, 849 .owner = THIS_MODULE, 850 .act = tcf_ife_act, 851 .dump = tcf_ife_dump, 852 .cleanup = tcf_ife_cleanup, 853 .init = tcf_ife_init, 854 .walk = tcf_ife_walker, 855 .lookup = tcf_ife_search, 856 .size = sizeof(struct tcf_ife_info), 857 }; 858 859 static __net_init int ife_init_net(struct net *net) 860 { 861 struct tc_action_net *tn = net_generic(net, ife_net_id); 862 863 return tc_action_net_init(tn, &act_ife_ops); 864 } 865 866 static void __net_exit ife_exit_net(struct list_head *net_list) 867 { 868 tc_action_net_exit(net_list, ife_net_id); 869 } 870 871 static struct pernet_operations ife_net_ops = { 872 .init = ife_init_net, 873 .exit_batch = ife_exit_net, 874 .id = &ife_net_id, 875 .size = sizeof(struct tc_action_net), 876 }; 877 878 static int __init ife_init_module(void) 879 { 880 return tcf_register_action(&act_ife_ops, &ife_net_ops); 881 } 882 883 static void __exit ife_cleanup_module(void) 884 { 885 tcf_unregister_action(&act_ife_ops, &ife_net_ops); 886 } 887 888 module_init(ife_init_module); 889 module_exit(ife_cleanup_module); 890 891 MODULE_AUTHOR("Jamal Hadi Salim(2015)"); 892 MODULE_DESCRIPTION("Inter-FE LFB action"); 893 MODULE_LICENSE("GPL"); 894