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 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 /* Caller takes care of presenting data in network order 50 */ 51 int ife_tlv_meta_encode(void *skbdata, u16 attrtype, u16 dlen, const void *dval) 52 { 53 u32 *tlv = (u32 *)(skbdata); 54 u16 totlen = nla_total_size(dlen); /*alignment + hdr */ 55 char *dptr = (char *)tlv + NLA_HDRLEN; 56 u32 htlv = attrtype << 16 | dlen; 57 58 *tlv = htonl(htlv); 59 memset(dptr, 0, totlen - NLA_HDRLEN); 60 memcpy(dptr, dval, dlen); 61 62 return totlen; 63 } 64 EXPORT_SYMBOL_GPL(ife_tlv_meta_encode); 65 66 int ife_encode_meta_u16(u16 metaval, void *skbdata, struct tcf_meta_info *mi) 67 { 68 u16 edata = 0; 69 70 if (mi->metaval) 71 edata = *(u16 *)mi->metaval; 72 else if (metaval) 73 edata = metaval; 74 75 if (!edata) /* will not encode */ 76 return 0; 77 78 edata = htons(edata); 79 return ife_tlv_meta_encode(skbdata, mi->metaid, 2, &edata); 80 } 81 EXPORT_SYMBOL_GPL(ife_encode_meta_u16); 82 83 int ife_get_meta_u32(struct sk_buff *skb, struct tcf_meta_info *mi) 84 { 85 if (mi->metaval) 86 return nla_put_u32(skb, mi->metaid, *(u32 *)mi->metaval); 87 else 88 return nla_put(skb, mi->metaid, 0, NULL); 89 } 90 EXPORT_SYMBOL_GPL(ife_get_meta_u32); 91 92 int ife_check_meta_u32(u32 metaval, struct tcf_meta_info *mi) 93 { 94 if (metaval || mi->metaval) 95 return 8; /* T+L+V == 2+2+4 */ 96 97 return 0; 98 } 99 EXPORT_SYMBOL_GPL(ife_check_meta_u32); 100 101 int ife_check_meta_u16(u16 metaval, struct tcf_meta_info *mi) 102 { 103 if (metaval || mi->metaval) 104 return 8; /* T+L+(V) == 2+2+(2+2bytepad) */ 105 106 return 0; 107 } 108 EXPORT_SYMBOL_GPL(ife_check_meta_u16); 109 110 int ife_encode_meta_u32(u32 metaval, void *skbdata, struct tcf_meta_info *mi) 111 { 112 u32 edata = metaval; 113 114 if (mi->metaval) 115 edata = *(u32 *)mi->metaval; 116 else if (metaval) 117 edata = metaval; 118 119 if (!edata) /* will not encode */ 120 return 0; 121 122 edata = htonl(edata); 123 return ife_tlv_meta_encode(skbdata, mi->metaid, 4, &edata); 124 } 125 EXPORT_SYMBOL_GPL(ife_encode_meta_u32); 126 127 int ife_get_meta_u16(struct sk_buff *skb, struct tcf_meta_info *mi) 128 { 129 if (mi->metaval) 130 return nla_put_u16(skb, mi->metaid, *(u16 *)mi->metaval); 131 else 132 return nla_put(skb, mi->metaid, 0, NULL); 133 } 134 EXPORT_SYMBOL_GPL(ife_get_meta_u16); 135 136 int ife_alloc_meta_u32(struct tcf_meta_info *mi, void *metaval, gfp_t gfp) 137 { 138 mi->metaval = kmemdup(metaval, sizeof(u32), gfp); 139 if (!mi->metaval) 140 return -ENOMEM; 141 142 return 0; 143 } 144 EXPORT_SYMBOL_GPL(ife_alloc_meta_u32); 145 146 int ife_alloc_meta_u16(struct tcf_meta_info *mi, void *metaval, gfp_t gfp) 147 { 148 mi->metaval = kmemdup(metaval, sizeof(u16), gfp); 149 if (!mi->metaval) 150 return -ENOMEM; 151 152 return 0; 153 } 154 EXPORT_SYMBOL_GPL(ife_alloc_meta_u16); 155 156 void ife_release_meta_gen(struct tcf_meta_info *mi) 157 { 158 kfree(mi->metaval); 159 } 160 EXPORT_SYMBOL_GPL(ife_release_meta_gen); 161 162 int ife_validate_meta_u32(void *val, int len) 163 { 164 if (len == sizeof(u32)) 165 return 0; 166 167 return -EINVAL; 168 } 169 EXPORT_SYMBOL_GPL(ife_validate_meta_u32); 170 171 int ife_validate_meta_u16(void *val, int len) 172 { 173 /* length will not include padding */ 174 if (len == sizeof(u16)) 175 return 0; 176 177 return -EINVAL; 178 } 179 EXPORT_SYMBOL_GPL(ife_validate_meta_u16); 180 181 static LIST_HEAD(ifeoplist); 182 static DEFINE_RWLOCK(ife_mod_lock); 183 184 static struct tcf_meta_ops *find_ife_oplist(u16 metaid) 185 { 186 struct tcf_meta_ops *o; 187 188 read_lock(&ife_mod_lock); 189 list_for_each_entry(o, &ifeoplist, list) { 190 if (o->metaid == metaid) { 191 if (!try_module_get(o->owner)) 192 o = NULL; 193 read_unlock(&ife_mod_lock); 194 return o; 195 } 196 } 197 read_unlock(&ife_mod_lock); 198 199 return NULL; 200 } 201 202 int register_ife_op(struct tcf_meta_ops *mops) 203 { 204 struct tcf_meta_ops *m; 205 206 if (!mops->metaid || !mops->metatype || !mops->name || 207 !mops->check_presence || !mops->encode || !mops->decode || 208 !mops->get || !mops->alloc) 209 return -EINVAL; 210 211 write_lock(&ife_mod_lock); 212 213 list_for_each_entry(m, &ifeoplist, list) { 214 if (m->metaid == mops->metaid || 215 (strcmp(mops->name, m->name) == 0)) { 216 write_unlock(&ife_mod_lock); 217 return -EEXIST; 218 } 219 } 220 221 if (!mops->release) 222 mops->release = ife_release_meta_gen; 223 224 list_add_tail(&mops->list, &ifeoplist); 225 write_unlock(&ife_mod_lock); 226 return 0; 227 } 228 EXPORT_SYMBOL_GPL(unregister_ife_op); 229 230 int unregister_ife_op(struct tcf_meta_ops *mops) 231 { 232 struct tcf_meta_ops *m; 233 int err = -ENOENT; 234 235 write_lock(&ife_mod_lock); 236 list_for_each_entry(m, &ifeoplist, list) { 237 if (m->metaid == mops->metaid) { 238 list_del(&mops->list); 239 err = 0; 240 break; 241 } 242 } 243 write_unlock(&ife_mod_lock); 244 245 return err; 246 } 247 EXPORT_SYMBOL_GPL(register_ife_op); 248 249 static int ife_validate_metatype(struct tcf_meta_ops *ops, void *val, int len) 250 { 251 int ret = 0; 252 /* XXX: unfortunately cant use nla_policy at this point 253 * because a length of 0 is valid in the case of 254 * "allow". "use" semantics do enforce for proper 255 * length and i couldve use nla_policy but it makes it hard 256 * to use it just for that.. 257 */ 258 if (ops->validate) 259 return ops->validate(val, len); 260 261 if (ops->metatype == NLA_U32) 262 ret = ife_validate_meta_u32(val, len); 263 else if (ops->metatype == NLA_U16) 264 ret = ife_validate_meta_u16(val, len); 265 266 return ret; 267 } 268 269 /* called when adding new meta information 270 * under ife->tcf_lock for existing action 271 */ 272 static int load_metaops_and_vet(struct tcf_ife_info *ife, u32 metaid, 273 void *val, int len, bool exists) 274 { 275 struct tcf_meta_ops *ops = find_ife_oplist(metaid); 276 int ret = 0; 277 278 if (!ops) { 279 ret = -ENOENT; 280 #ifdef CONFIG_MODULES 281 if (exists) 282 spin_unlock_bh(&ife->tcf_lock); 283 rtnl_unlock(); 284 request_module("ifemeta%u", metaid); 285 rtnl_lock(); 286 if (exists) 287 spin_lock_bh(&ife->tcf_lock); 288 ops = find_ife_oplist(metaid); 289 #endif 290 } 291 292 if (ops) { 293 ret = 0; 294 if (len) 295 ret = ife_validate_metatype(ops, val, len); 296 297 module_put(ops->owner); 298 } 299 300 return ret; 301 } 302 303 /* called when adding new meta information 304 * under ife->tcf_lock for existing action 305 */ 306 static int add_metainfo(struct tcf_ife_info *ife, u32 metaid, void *metaval, 307 int len, bool atomic) 308 { 309 struct tcf_meta_info *mi = NULL; 310 struct tcf_meta_ops *ops = find_ife_oplist(metaid); 311 int ret = 0; 312 313 if (!ops) 314 return -ENOENT; 315 316 mi = kzalloc(sizeof(*mi), atomic ? GFP_ATOMIC : GFP_KERNEL); 317 if (!mi) { 318 /*put back what find_ife_oplist took */ 319 module_put(ops->owner); 320 return -ENOMEM; 321 } 322 323 mi->metaid = metaid; 324 mi->ops = ops; 325 if (len > 0) { 326 ret = ops->alloc(mi, metaval, atomic ? GFP_ATOMIC : GFP_KERNEL); 327 if (ret != 0) { 328 kfree(mi); 329 module_put(ops->owner); 330 return ret; 331 } 332 } 333 334 list_add_tail(&mi->metalist, &ife->metalist); 335 336 return ret; 337 } 338 339 static int use_all_metadata(struct tcf_ife_info *ife) 340 { 341 struct tcf_meta_ops *o; 342 int rc = 0; 343 int installed = 0; 344 345 read_lock(&ife_mod_lock); 346 list_for_each_entry(o, &ifeoplist, list) { 347 rc = add_metainfo(ife, o->metaid, NULL, 0, true); 348 if (rc == 0) 349 installed += 1; 350 } 351 read_unlock(&ife_mod_lock); 352 353 if (installed) 354 return 0; 355 else 356 return -EINVAL; 357 } 358 359 static int dump_metalist(struct sk_buff *skb, struct tcf_ife_info *ife) 360 { 361 struct tcf_meta_info *e; 362 struct nlattr *nest; 363 unsigned char *b = skb_tail_pointer(skb); 364 int total_encoded = 0; 365 366 /*can only happen on decode */ 367 if (list_empty(&ife->metalist)) 368 return 0; 369 370 nest = nla_nest_start(skb, TCA_IFE_METALST); 371 if (!nest) 372 goto out_nlmsg_trim; 373 374 list_for_each_entry(e, &ife->metalist, metalist) { 375 if (!e->ops->get(skb, e)) 376 total_encoded += 1; 377 } 378 379 if (!total_encoded) 380 goto out_nlmsg_trim; 381 382 nla_nest_end(skb, nest); 383 384 return 0; 385 386 out_nlmsg_trim: 387 nlmsg_trim(skb, b); 388 return -1; 389 } 390 391 /* under ife->tcf_lock */ 392 static void _tcf_ife_cleanup(struct tc_action *a, int bind) 393 { 394 struct tcf_ife_info *ife = to_ife(a); 395 struct tcf_meta_info *e, *n; 396 397 list_for_each_entry_safe(e, n, &ife->metalist, metalist) { 398 module_put(e->ops->owner); 399 list_del(&e->metalist); 400 if (e->metaval) { 401 if (e->ops->release) 402 e->ops->release(e); 403 else 404 kfree(e->metaval); 405 } 406 kfree(e); 407 } 408 } 409 410 static void tcf_ife_cleanup(struct tc_action *a, int bind) 411 { 412 struct tcf_ife_info *ife = to_ife(a); 413 414 spin_lock_bh(&ife->tcf_lock); 415 _tcf_ife_cleanup(a, bind); 416 spin_unlock_bh(&ife->tcf_lock); 417 } 418 419 /* under ife->tcf_lock for existing action */ 420 static int populate_metalist(struct tcf_ife_info *ife, struct nlattr **tb, 421 bool exists) 422 { 423 int len = 0; 424 int rc = 0; 425 int i = 0; 426 void *val; 427 428 for (i = 1; i < max_metacnt; i++) { 429 if (tb[i]) { 430 val = nla_data(tb[i]); 431 len = nla_len(tb[i]); 432 433 rc = load_metaops_and_vet(ife, i, val, len, exists); 434 if (rc != 0) 435 return rc; 436 437 rc = add_metainfo(ife, i, val, len, exists); 438 if (rc) 439 return rc; 440 } 441 } 442 443 return rc; 444 } 445 446 static int tcf_ife_init(struct net *net, struct nlattr *nla, 447 struct nlattr *est, struct tc_action **a, 448 int ovr, int bind) 449 { 450 struct tc_action_net *tn = net_generic(net, ife_net_id); 451 struct nlattr *tb[TCA_IFE_MAX + 1]; 452 struct nlattr *tb2[IFE_META_MAX + 1]; 453 struct tcf_ife_info *ife; 454 struct tc_ife *parm; 455 u16 ife_type = 0; 456 u8 *daddr = NULL; 457 u8 *saddr = NULL; 458 bool exists = false; 459 int ret = 0; 460 int err; 461 462 err = nla_parse_nested(tb, TCA_IFE_MAX, nla, ife_policy); 463 if (err < 0) 464 return err; 465 466 if (!tb[TCA_IFE_PARMS]) 467 return -EINVAL; 468 469 parm = nla_data(tb[TCA_IFE_PARMS]); 470 471 exists = tcf_hash_check(tn, parm->index, a, bind); 472 if (exists && bind) 473 return 0; 474 475 if (parm->flags & IFE_ENCODE) { 476 /* Until we get issued the ethertype, we cant have 477 * a default.. 478 **/ 479 if (!tb[TCA_IFE_TYPE]) { 480 if (exists) 481 tcf_hash_release(*a, bind); 482 pr_info("You MUST pass etherype for encoding\n"); 483 return -EINVAL; 484 } 485 } 486 487 if (!exists) { 488 ret = tcf_hash_create(tn, parm->index, est, a, &act_ife_ops, 489 bind, false); 490 if (ret) 491 return ret; 492 ret = ACT_P_CREATED; 493 } else { 494 tcf_hash_release(*a, bind); 495 if (!ovr) 496 return -EEXIST; 497 } 498 499 ife = to_ife(*a); 500 ife->flags = parm->flags; 501 502 if (parm->flags & IFE_ENCODE) { 503 ife_type = nla_get_u16(tb[TCA_IFE_TYPE]); 504 if (tb[TCA_IFE_DMAC]) 505 daddr = nla_data(tb[TCA_IFE_DMAC]); 506 if (tb[TCA_IFE_SMAC]) 507 saddr = nla_data(tb[TCA_IFE_SMAC]); 508 } 509 510 if (exists) 511 spin_lock_bh(&ife->tcf_lock); 512 ife->tcf_action = parm->action; 513 514 if (parm->flags & IFE_ENCODE) { 515 if (daddr) 516 ether_addr_copy(ife->eth_dst, daddr); 517 else 518 eth_zero_addr(ife->eth_dst); 519 520 if (saddr) 521 ether_addr_copy(ife->eth_src, saddr); 522 else 523 eth_zero_addr(ife->eth_src); 524 525 ife->eth_type = ife_type; 526 } 527 528 if (ret == ACT_P_CREATED) 529 INIT_LIST_HEAD(&ife->metalist); 530 531 if (tb[TCA_IFE_METALST]) { 532 err = nla_parse_nested(tb2, IFE_META_MAX, tb[TCA_IFE_METALST], 533 NULL); 534 if (err) { 535 metadata_parse_err: 536 if (exists) 537 tcf_hash_release(*a, bind); 538 if (ret == ACT_P_CREATED) 539 _tcf_ife_cleanup(*a, bind); 540 541 if (exists) 542 spin_unlock_bh(&ife->tcf_lock); 543 return err; 544 } 545 546 err = populate_metalist(ife, tb2, exists); 547 if (err) 548 goto metadata_parse_err; 549 550 } else { 551 /* if no passed metadata allow list or passed allow-all 552 * then here we process by adding as many supported metadatum 553 * as we can. You better have at least one else we are 554 * going to bail out 555 */ 556 err = use_all_metadata(ife); 557 if (err) { 558 if (ret == ACT_P_CREATED) 559 _tcf_ife_cleanup(*a, bind); 560 561 if (exists) 562 spin_unlock_bh(&ife->tcf_lock); 563 return err; 564 } 565 } 566 567 if (exists) 568 spin_unlock_bh(&ife->tcf_lock); 569 570 if (ret == ACT_P_CREATED) 571 tcf_hash_insert(tn, *a); 572 573 return ret; 574 } 575 576 static int tcf_ife_dump(struct sk_buff *skb, struct tc_action *a, int bind, 577 int ref) 578 { 579 unsigned char *b = skb_tail_pointer(skb); 580 struct tcf_ife_info *ife = to_ife(a); 581 struct tc_ife opt = { 582 .index = ife->tcf_index, 583 .refcnt = ife->tcf_refcnt - ref, 584 .bindcnt = ife->tcf_bindcnt - bind, 585 .action = ife->tcf_action, 586 .flags = ife->flags, 587 }; 588 struct tcf_t t; 589 590 if (nla_put(skb, TCA_IFE_PARMS, sizeof(opt), &opt)) 591 goto nla_put_failure; 592 593 tcf_tm_dump(&t, &ife->tcf_tm); 594 if (nla_put_64bit(skb, TCA_IFE_TM, sizeof(t), &t, TCA_IFE_PAD)) 595 goto nla_put_failure; 596 597 if (!is_zero_ether_addr(ife->eth_dst)) { 598 if (nla_put(skb, TCA_IFE_DMAC, ETH_ALEN, ife->eth_dst)) 599 goto nla_put_failure; 600 } 601 602 if (!is_zero_ether_addr(ife->eth_src)) { 603 if (nla_put(skb, TCA_IFE_SMAC, ETH_ALEN, ife->eth_src)) 604 goto nla_put_failure; 605 } 606 607 if (nla_put(skb, TCA_IFE_TYPE, 2, &ife->eth_type)) 608 goto nla_put_failure; 609 610 if (dump_metalist(skb, ife)) { 611 /*ignore failure to dump metalist */ 612 pr_info("Failed to dump metalist\n"); 613 } 614 615 return skb->len; 616 617 nla_put_failure: 618 nlmsg_trim(skb, b); 619 return -1; 620 } 621 622 int find_decode_metaid(struct sk_buff *skb, struct tcf_ife_info *ife, 623 u16 metaid, u16 mlen, void *mdata) 624 { 625 struct tcf_meta_info *e; 626 627 /* XXX: use hash to speed up */ 628 list_for_each_entry(e, &ife->metalist, metalist) { 629 if (metaid == e->metaid) { 630 if (e->ops) { 631 /* We check for decode presence already */ 632 return e->ops->decode(skb, mdata, mlen); 633 } 634 } 635 } 636 637 return 0; 638 } 639 640 struct ifeheadr { 641 __be16 metalen; 642 u8 tlv_data[]; 643 }; 644 645 struct meta_tlvhdr { 646 __be16 type; 647 __be16 len; 648 }; 649 650 static int tcf_ife_decode(struct sk_buff *skb, const struct tc_action *a, 651 struct tcf_result *res) 652 { 653 struct tcf_ife_info *ife = to_ife(a); 654 int action = ife->tcf_action; 655 struct ifeheadr *ifehdr = (struct ifeheadr *)skb->data; 656 u16 ifehdrln = ifehdr->metalen; 657 struct meta_tlvhdr *tlv = (struct meta_tlvhdr *)(ifehdr->tlv_data); 658 659 spin_lock(&ife->tcf_lock); 660 bstats_update(&ife->tcf_bstats, skb); 661 tcf_lastuse_update(&ife->tcf_tm); 662 spin_unlock(&ife->tcf_lock); 663 664 ifehdrln = ntohs(ifehdrln); 665 if (unlikely(!pskb_may_pull(skb, ifehdrln))) { 666 spin_lock(&ife->tcf_lock); 667 ife->tcf_qstats.drops++; 668 spin_unlock(&ife->tcf_lock); 669 return TC_ACT_SHOT; 670 } 671 672 skb_set_mac_header(skb, ifehdrln); 673 __skb_pull(skb, ifehdrln); 674 skb->protocol = eth_type_trans(skb, skb->dev); 675 ifehdrln -= IFE_METAHDRLEN; 676 677 while (ifehdrln > 0) { 678 u8 *tlvdata = (u8 *)tlv; 679 u16 mtype = tlv->type; 680 u16 mlen = tlv->len; 681 u16 alen; 682 683 mtype = ntohs(mtype); 684 mlen = ntohs(mlen); 685 alen = NLA_ALIGN(mlen); 686 687 if (find_decode_metaid(skb, ife, mtype, (mlen - NLA_HDRLEN), 688 (void *)(tlvdata + NLA_HDRLEN))) { 689 /* abuse overlimits to count when we receive metadata 690 * but dont have an ops for it 691 */ 692 pr_info_ratelimited("Unknown metaid %d alnlen %d\n", 693 mtype, mlen); 694 ife->tcf_qstats.overlimits++; 695 } 696 697 tlvdata += alen; 698 ifehdrln -= alen; 699 tlv = (struct meta_tlvhdr *)tlvdata; 700 } 701 702 skb_reset_network_header(skb); 703 return action; 704 } 705 706 /*XXX: check if we can do this at install time instead of current 707 * send data path 708 **/ 709 static int ife_get_sz(struct sk_buff *skb, struct tcf_ife_info *ife) 710 { 711 struct tcf_meta_info *e, *n; 712 int tot_run_sz = 0, run_sz = 0; 713 714 list_for_each_entry_safe(e, n, &ife->metalist, metalist) { 715 if (e->ops->check_presence) { 716 run_sz = e->ops->check_presence(skb, e); 717 tot_run_sz += run_sz; 718 } 719 } 720 721 return tot_run_sz; 722 } 723 724 static int tcf_ife_encode(struct sk_buff *skb, const struct tc_action *a, 725 struct tcf_result *res) 726 { 727 struct tcf_ife_info *ife = to_ife(a); 728 int action = ife->tcf_action; 729 struct ethhdr *oethh; /* outer ether header */ 730 struct ethhdr *iethh; /* inner eth header */ 731 struct tcf_meta_info *e; 732 /* 733 OUTERHDR:TOTMETALEN:{TLVHDR:Metadatum:TLVHDR..}:ORIGDATA 734 where ORIGDATA = original ethernet header ... 735 */ 736 u16 metalen = ife_get_sz(skb, ife); 737 int hdrm = metalen + skb->dev->hard_header_len + IFE_METAHDRLEN; 738 unsigned int skboff = skb->dev->hard_header_len; 739 u32 at = G_TC_AT(skb->tc_verd); 740 int new_len = skb->len + hdrm; 741 bool exceed_mtu = false; 742 int err; 743 744 if (at & AT_EGRESS) { 745 if (new_len > skb->dev->mtu) 746 exceed_mtu = true; 747 } 748 749 spin_lock(&ife->tcf_lock); 750 bstats_update(&ife->tcf_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 ife->tcf_qstats.overlimits++; 758 spin_unlock(&ife->tcf_lock); 759 return action; 760 } 761 /* could be stupid policy setup or mtu config 762 * so lets be conservative.. */ 763 if ((action == TC_ACT_SHOT) || exceed_mtu) { 764 ife->tcf_qstats.drops++; 765 spin_unlock(&ife->tcf_lock); 766 return TC_ACT_SHOT; 767 } 768 769 iethh = eth_hdr(skb); 770 771 err = skb_cow_head(skb, hdrm); 772 if (unlikely(err)) { 773 ife->tcf_qstats.drops++; 774 spin_unlock(&ife->tcf_lock); 775 return TC_ACT_SHOT; 776 } 777 778 if (!(at & AT_EGRESS)) 779 skb_push(skb, skb->dev->hard_header_len); 780 781 __skb_push(skb, hdrm); 782 memcpy(skb->data, iethh, skb->mac_len); 783 skb_reset_mac_header(skb); 784 oethh = eth_hdr(skb); 785 786 /*total metadata length */ 787 metalen += IFE_METAHDRLEN; 788 metalen = htons(metalen); 789 memcpy((skb->data + skboff), &metalen, IFE_METAHDRLEN); 790 skboff += IFE_METAHDRLEN; 791 792 /* XXX: we dont have a clever way of telling encode to 793 * not repeat some of the computations that are done by 794 * ops->presence_check... 795 */ 796 list_for_each_entry(e, &ife->metalist, metalist) { 797 if (e->ops->encode) { 798 err = e->ops->encode(skb, (void *)(skb->data + skboff), 799 e); 800 } 801 if (err < 0) { 802 /* too corrupt to keep around if overwritten */ 803 ife->tcf_qstats.drops++; 804 spin_unlock(&ife->tcf_lock); 805 return TC_ACT_SHOT; 806 } 807 skboff += err; 808 } 809 810 if (!is_zero_ether_addr(ife->eth_src)) 811 ether_addr_copy(oethh->h_source, ife->eth_src); 812 else 813 ether_addr_copy(oethh->h_source, iethh->h_source); 814 if (!is_zero_ether_addr(ife->eth_dst)) 815 ether_addr_copy(oethh->h_dest, ife->eth_dst); 816 else 817 ether_addr_copy(oethh->h_dest, iethh->h_dest); 818 oethh->h_proto = htons(ife->eth_type); 819 820 if (!(at & AT_EGRESS)) 821 skb_pull(skb, skb->dev->hard_header_len); 822 823 spin_unlock(&ife->tcf_lock); 824 825 return action; 826 } 827 828 static int tcf_ife_act(struct sk_buff *skb, const struct tc_action *a, 829 struct tcf_result *res) 830 { 831 struct tcf_ife_info *ife = to_ife(a); 832 833 if (ife->flags & IFE_ENCODE) 834 return tcf_ife_encode(skb, a, res); 835 836 if (!(ife->flags & IFE_ENCODE)) 837 return tcf_ife_decode(skb, a, res); 838 839 pr_info_ratelimited("unknown failure(policy neither de/encode\n"); 840 spin_lock(&ife->tcf_lock); 841 bstats_update(&ife->tcf_bstats, skb); 842 tcf_lastuse_update(&ife->tcf_tm); 843 ife->tcf_qstats.drops++; 844 spin_unlock(&ife->tcf_lock); 845 846 return TC_ACT_SHOT; 847 } 848 849 static int tcf_ife_walker(struct net *net, struct sk_buff *skb, 850 struct netlink_callback *cb, int type, 851 const struct tc_action_ops *ops) 852 { 853 struct tc_action_net *tn = net_generic(net, ife_net_id); 854 855 return tcf_generic_walker(tn, skb, cb, type, ops); 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_hash_search(tn, a, index); 863 } 864 865 static struct tc_action_ops act_ife_ops = { 866 .kind = "ife", 867 .type = TCA_ACT_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, IFE_TAB_MASK); 883 } 884 885 static void __net_exit ife_exit_net(struct net *net) 886 { 887 struct tc_action_net *tn = net_generic(net, ife_net_id); 888 889 tc_action_net_exit(tn); 890 } 891 892 static struct pernet_operations ife_net_ops = { 893 .init = ife_init_net, 894 .exit = ife_exit_net, 895 .id = &ife_net_id, 896 .size = sizeof(struct tc_action_net), 897 }; 898 899 static int __init ife_init_module(void) 900 { 901 return tcf_register_action(&act_ife_ops, &ife_net_ops); 902 } 903 904 static void __exit ife_cleanup_module(void) 905 { 906 tcf_unregister_action(&act_ife_ops, &ife_net_ops); 907 } 908 909 module_init(ife_init_module); 910 module_exit(ife_cleanup_module); 911 912 MODULE_AUTHOR("Jamal Hadi Salim(2015)"); 913 MODULE_DESCRIPTION("Inter-FE LFB action"); 914 MODULE_LICENSE("GPL"); 915