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 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 /* Caller takes care of presenting data in network order 49 */ 50 int ife_tlv_meta_encode(void *skbdata, u16 attrtype, u16 dlen, const void *dval) 51 { 52 u32 *tlv = (u32 *)(skbdata); 53 u16 totlen = nla_total_size(dlen); /*alignment + hdr */ 54 char *dptr = (char *)tlv + NLA_HDRLEN; 55 u32 htlv = attrtype << 16 | totlen; 56 57 *tlv = htonl(htlv); 58 memset(dptr, 0, totlen - NLA_HDRLEN); 59 memcpy(dptr, dval, dlen); 60 61 return totlen; 62 } 63 EXPORT_SYMBOL_GPL(ife_tlv_meta_encode); 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_encode_meta_u32(u32 metaval, void *skbdata, struct tcf_meta_info *mi) 84 { 85 u32 edata = metaval; 86 87 if (mi->metaval) 88 edata = *(u32 *)mi->metaval; 89 else if (metaval) 90 edata = metaval; 91 92 if (!edata) /* will not encode */ 93 return 0; 94 95 edata = htonl(edata); 96 return ife_tlv_meta_encode(skbdata, mi->metaid, 4, &edata); 97 } 98 EXPORT_SYMBOL_GPL(ife_encode_meta_u32); 99 100 int ife_get_meta_u16(struct sk_buff *skb, struct tcf_meta_info *mi) 101 { 102 if (mi->metaval) 103 return nla_put_u16(skb, mi->metaid, *(u16 *)mi->metaval); 104 else 105 return nla_put(skb, mi->metaid, 0, NULL); 106 } 107 EXPORT_SYMBOL_GPL(ife_get_meta_u16); 108 109 int ife_alloc_meta_u32(struct tcf_meta_info *mi, void *metaval, gfp_t gfp) 110 { 111 mi->metaval = kmemdup(metaval, sizeof(u32), gfp); 112 if (!mi->metaval) 113 return -ENOMEM; 114 115 return 0; 116 } 117 EXPORT_SYMBOL_GPL(ife_alloc_meta_u32); 118 119 int ife_alloc_meta_u16(struct tcf_meta_info *mi, void *metaval, gfp_t gfp) 120 { 121 mi->metaval = kmemdup(metaval, sizeof(u16), gfp); 122 if (!mi->metaval) 123 return -ENOMEM; 124 125 return 0; 126 } 127 EXPORT_SYMBOL_GPL(ife_alloc_meta_u16); 128 129 void ife_release_meta_gen(struct tcf_meta_info *mi) 130 { 131 kfree(mi->metaval); 132 } 133 EXPORT_SYMBOL_GPL(ife_release_meta_gen); 134 135 int ife_validate_meta_u32(void *val, int len) 136 { 137 if (len == 4) 138 return 0; 139 140 return -EINVAL; 141 } 142 EXPORT_SYMBOL_GPL(ife_validate_meta_u32); 143 144 int ife_validate_meta_u16(void *val, int len) 145 { 146 /* length will include padding */ 147 if (len == NLA_ALIGN(2)) 148 return 0; 149 150 return -EINVAL; 151 } 152 EXPORT_SYMBOL_GPL(ife_validate_meta_u16); 153 154 static LIST_HEAD(ifeoplist); 155 static DEFINE_RWLOCK(ife_mod_lock); 156 157 static struct tcf_meta_ops *find_ife_oplist(u16 metaid) 158 { 159 struct tcf_meta_ops *o; 160 161 read_lock(&ife_mod_lock); 162 list_for_each_entry(o, &ifeoplist, list) { 163 if (o->metaid == metaid) { 164 if (!try_module_get(o->owner)) 165 o = NULL; 166 read_unlock(&ife_mod_lock); 167 return o; 168 } 169 } 170 read_unlock(&ife_mod_lock); 171 172 return NULL; 173 } 174 175 int register_ife_op(struct tcf_meta_ops *mops) 176 { 177 struct tcf_meta_ops *m; 178 179 if (!mops->metaid || !mops->metatype || !mops->name || 180 !mops->check_presence || !mops->encode || !mops->decode || 181 !mops->get || !mops->alloc) 182 return -EINVAL; 183 184 write_lock(&ife_mod_lock); 185 186 list_for_each_entry(m, &ifeoplist, list) { 187 if (m->metaid == mops->metaid || 188 (strcmp(mops->name, m->name) == 0)) { 189 write_unlock(&ife_mod_lock); 190 return -EEXIST; 191 } 192 } 193 194 if (!mops->release) 195 mops->release = ife_release_meta_gen; 196 197 list_add_tail(&mops->list, &ifeoplist); 198 write_unlock(&ife_mod_lock); 199 return 0; 200 } 201 EXPORT_SYMBOL_GPL(unregister_ife_op); 202 203 int unregister_ife_op(struct tcf_meta_ops *mops) 204 { 205 struct tcf_meta_ops *m; 206 int err = -ENOENT; 207 208 write_lock(&ife_mod_lock); 209 list_for_each_entry(m, &ifeoplist, list) { 210 if (m->metaid == mops->metaid) { 211 list_del(&mops->list); 212 err = 0; 213 break; 214 } 215 } 216 write_unlock(&ife_mod_lock); 217 218 return err; 219 } 220 EXPORT_SYMBOL_GPL(register_ife_op); 221 222 static int ife_validate_metatype(struct tcf_meta_ops *ops, void *val, int len) 223 { 224 int ret = 0; 225 /* XXX: unfortunately cant use nla_policy at this point 226 * because a length of 0 is valid in the case of 227 * "allow". "use" semantics do enforce for proper 228 * length and i couldve use nla_policy but it makes it hard 229 * to use it just for that.. 230 */ 231 if (ops->validate) 232 return ops->validate(val, len); 233 234 if (ops->metatype == NLA_U32) 235 ret = ife_validate_meta_u32(val, len); 236 else if (ops->metatype == NLA_U16) 237 ret = ife_validate_meta_u16(val, len); 238 239 return ret; 240 } 241 242 /* called when adding new meta information 243 * under ife->tcf_lock for existing action 244 */ 245 static int load_metaops_and_vet(struct tcf_ife_info *ife, u32 metaid, 246 void *val, int len, bool exists) 247 { 248 struct tcf_meta_ops *ops = find_ife_oplist(metaid); 249 int ret = 0; 250 251 if (!ops) { 252 ret = -ENOENT; 253 #ifdef CONFIG_MODULES 254 if (exists) 255 spin_unlock_bh(&ife->tcf_lock); 256 rtnl_unlock(); 257 request_module("ifemeta%u", metaid); 258 rtnl_lock(); 259 if (exists) 260 spin_lock_bh(&ife->tcf_lock); 261 ops = find_ife_oplist(metaid); 262 #endif 263 } 264 265 if (ops) { 266 ret = 0; 267 if (len) 268 ret = ife_validate_metatype(ops, val, len); 269 270 module_put(ops->owner); 271 } 272 273 return ret; 274 } 275 276 /* called when adding new meta information 277 * under ife->tcf_lock for existing action 278 */ 279 static int add_metainfo(struct tcf_ife_info *ife, u32 metaid, void *metaval, 280 int len, bool atomic) 281 { 282 struct tcf_meta_info *mi = NULL; 283 struct tcf_meta_ops *ops = find_ife_oplist(metaid); 284 int ret = 0; 285 286 if (!ops) 287 return -ENOENT; 288 289 mi = kzalloc(sizeof(*mi), atomic ? GFP_ATOMIC : GFP_KERNEL); 290 if (!mi) { 291 /*put back what find_ife_oplist took */ 292 module_put(ops->owner); 293 return -ENOMEM; 294 } 295 296 mi->metaid = metaid; 297 mi->ops = ops; 298 if (len > 0) { 299 ret = ops->alloc(mi, metaval, atomic ? GFP_ATOMIC : GFP_KERNEL); 300 if (ret != 0) { 301 kfree(mi); 302 module_put(ops->owner); 303 return ret; 304 } 305 } 306 307 list_add_tail(&mi->metalist, &ife->metalist); 308 309 return ret; 310 } 311 312 static int use_all_metadata(struct tcf_ife_info *ife) 313 { 314 struct tcf_meta_ops *o; 315 int rc = 0; 316 int installed = 0; 317 318 read_lock(&ife_mod_lock); 319 list_for_each_entry(o, &ifeoplist, list) { 320 rc = add_metainfo(ife, o->metaid, NULL, 0, true); 321 if (rc == 0) 322 installed += 1; 323 } 324 read_unlock(&ife_mod_lock); 325 326 if (installed) 327 return 0; 328 else 329 return -EINVAL; 330 } 331 332 static int dump_metalist(struct sk_buff *skb, struct tcf_ife_info *ife) 333 { 334 struct tcf_meta_info *e; 335 struct nlattr *nest; 336 unsigned char *b = skb_tail_pointer(skb); 337 int total_encoded = 0; 338 339 /*can only happen on decode */ 340 if (list_empty(&ife->metalist)) 341 return 0; 342 343 nest = nla_nest_start(skb, TCA_IFE_METALST); 344 if (!nest) 345 goto out_nlmsg_trim; 346 347 list_for_each_entry(e, &ife->metalist, metalist) { 348 if (!e->ops->get(skb, e)) 349 total_encoded += 1; 350 } 351 352 if (!total_encoded) 353 goto out_nlmsg_trim; 354 355 nla_nest_end(skb, nest); 356 357 return 0; 358 359 out_nlmsg_trim: 360 nlmsg_trim(skb, b); 361 return -1; 362 } 363 364 /* under ife->tcf_lock */ 365 static void _tcf_ife_cleanup(struct tc_action *a, int bind) 366 { 367 struct tcf_ife_info *ife = a->priv; 368 struct tcf_meta_info *e, *n; 369 370 list_for_each_entry_safe(e, n, &ife->metalist, metalist) { 371 module_put(e->ops->owner); 372 list_del(&e->metalist); 373 if (e->metaval) { 374 if (e->ops->release) 375 e->ops->release(e); 376 else 377 kfree(e->metaval); 378 } 379 kfree(e); 380 } 381 } 382 383 static void tcf_ife_cleanup(struct tc_action *a, int bind) 384 { 385 struct tcf_ife_info *ife = a->priv; 386 387 spin_lock_bh(&ife->tcf_lock); 388 _tcf_ife_cleanup(a, bind); 389 spin_unlock_bh(&ife->tcf_lock); 390 } 391 392 /* under ife->tcf_lock for existing action */ 393 static int populate_metalist(struct tcf_ife_info *ife, struct nlattr **tb, 394 bool exists) 395 { 396 int len = 0; 397 int rc = 0; 398 int i = 0; 399 void *val; 400 401 for (i = 1; i < max_metacnt; i++) { 402 if (tb[i]) { 403 val = nla_data(tb[i]); 404 len = nla_len(tb[i]); 405 406 rc = load_metaops_and_vet(ife, i, val, len, exists); 407 if (rc != 0) 408 return rc; 409 410 rc = add_metainfo(ife, i, val, len, exists); 411 if (rc) 412 return rc; 413 } 414 } 415 416 return rc; 417 } 418 419 static int tcf_ife_init(struct net *net, struct nlattr *nla, 420 struct nlattr *est, struct tc_action *a, 421 int ovr, int bind) 422 { 423 struct tc_action_net *tn = net_generic(net, ife_net_id); 424 struct nlattr *tb[TCA_IFE_MAX + 1]; 425 struct nlattr *tb2[IFE_META_MAX + 1]; 426 struct tcf_ife_info *ife; 427 struct tc_ife *parm; 428 u16 ife_type = 0; 429 u8 *daddr = NULL; 430 u8 *saddr = NULL; 431 int ret = 0, exists = 0; 432 int err; 433 434 err = nla_parse_nested(tb, TCA_IFE_MAX, nla, ife_policy); 435 if (err < 0) 436 return err; 437 438 if (!tb[TCA_IFE_PARMS]) 439 return -EINVAL; 440 441 parm = nla_data(tb[TCA_IFE_PARMS]); 442 443 exists = tcf_hash_check(tn, parm->index, a, bind); 444 if (exists && bind) 445 return 0; 446 447 if (parm->flags & IFE_ENCODE) { 448 /* Until we get issued the ethertype, we cant have 449 * a default.. 450 **/ 451 if (!tb[TCA_IFE_TYPE]) { 452 if (exists) 453 tcf_hash_release(a, bind); 454 pr_info("You MUST pass etherype for encoding\n"); 455 return -EINVAL; 456 } 457 } 458 459 if (!exists) { 460 ret = tcf_hash_create(tn, parm->index, est, a, sizeof(*ife), 461 bind, false); 462 if (ret) 463 return ret; 464 ret = ACT_P_CREATED; 465 } else { 466 tcf_hash_release(a, bind); 467 if (!ovr) 468 return -EEXIST; 469 } 470 471 ife = to_ife(a); 472 ife->flags = parm->flags; 473 474 if (parm->flags & IFE_ENCODE) { 475 ife_type = nla_get_u16(tb[TCA_IFE_TYPE]); 476 if (tb[TCA_IFE_DMAC]) 477 daddr = nla_data(tb[TCA_IFE_DMAC]); 478 if (tb[TCA_IFE_SMAC]) 479 saddr = nla_data(tb[TCA_IFE_SMAC]); 480 } 481 482 if (exists) 483 spin_lock_bh(&ife->tcf_lock); 484 ife->tcf_action = parm->action; 485 486 if (parm->flags & IFE_ENCODE) { 487 if (daddr) 488 ether_addr_copy(ife->eth_dst, daddr); 489 else 490 eth_zero_addr(ife->eth_dst); 491 492 if (saddr) 493 ether_addr_copy(ife->eth_src, saddr); 494 else 495 eth_zero_addr(ife->eth_src); 496 497 ife->eth_type = ife_type; 498 } 499 500 if (ret == ACT_P_CREATED) 501 INIT_LIST_HEAD(&ife->metalist); 502 503 if (tb[TCA_IFE_METALST]) { 504 err = nla_parse_nested(tb2, IFE_META_MAX, tb[TCA_IFE_METALST], 505 NULL); 506 if (err) { 507 metadata_parse_err: 508 if (exists) 509 tcf_hash_release(a, bind); 510 if (ret == ACT_P_CREATED) 511 _tcf_ife_cleanup(a, bind); 512 513 if (exists) 514 spin_unlock_bh(&ife->tcf_lock); 515 return err; 516 } 517 518 err = populate_metalist(ife, tb2, exists); 519 if (err) 520 goto metadata_parse_err; 521 522 } else { 523 /* if no passed metadata allow list or passed allow-all 524 * then here we process by adding as many supported metadatum 525 * as we can. You better have at least one else we are 526 * going to bail out 527 */ 528 err = use_all_metadata(ife); 529 if (err) { 530 if (ret == ACT_P_CREATED) 531 _tcf_ife_cleanup(a, bind); 532 533 if (exists) 534 spin_unlock_bh(&ife->tcf_lock); 535 return err; 536 } 537 } 538 539 if (exists) 540 spin_unlock_bh(&ife->tcf_lock); 541 542 if (ret == ACT_P_CREATED) 543 tcf_hash_insert(tn, a); 544 545 return ret; 546 } 547 548 static int tcf_ife_dump(struct sk_buff *skb, struct tc_action *a, int bind, 549 int ref) 550 { 551 unsigned char *b = skb_tail_pointer(skb); 552 struct tcf_ife_info *ife = a->priv; 553 struct tc_ife opt = { 554 .index = ife->tcf_index, 555 .refcnt = ife->tcf_refcnt - ref, 556 .bindcnt = ife->tcf_bindcnt - bind, 557 .action = ife->tcf_action, 558 .flags = ife->flags, 559 }; 560 struct tcf_t t; 561 562 if (nla_put(skb, TCA_IFE_PARMS, sizeof(opt), &opt)) 563 goto nla_put_failure; 564 565 t.install = jiffies_to_clock_t(jiffies - ife->tcf_tm.install); 566 t.lastuse = jiffies_to_clock_t(jiffies - ife->tcf_tm.lastuse); 567 t.expires = jiffies_to_clock_t(ife->tcf_tm.expires); 568 if (nla_put_64bit(skb, TCA_IFE_TM, sizeof(t), &t, TCA_IFE_PAD)) 569 goto nla_put_failure; 570 571 if (!is_zero_ether_addr(ife->eth_dst)) { 572 if (nla_put(skb, TCA_IFE_DMAC, ETH_ALEN, ife->eth_dst)) 573 goto nla_put_failure; 574 } 575 576 if (!is_zero_ether_addr(ife->eth_src)) { 577 if (nla_put(skb, TCA_IFE_SMAC, ETH_ALEN, ife->eth_src)) 578 goto nla_put_failure; 579 } 580 581 if (nla_put(skb, TCA_IFE_TYPE, 2, &ife->eth_type)) 582 goto nla_put_failure; 583 584 if (dump_metalist(skb, ife)) { 585 /*ignore failure to dump metalist */ 586 pr_info("Failed to dump metalist\n"); 587 } 588 589 return skb->len; 590 591 nla_put_failure: 592 nlmsg_trim(skb, b); 593 return -1; 594 } 595 596 int find_decode_metaid(struct sk_buff *skb, struct tcf_ife_info *ife, 597 u16 metaid, u16 mlen, void *mdata) 598 { 599 struct tcf_meta_info *e; 600 601 /* XXX: use hash to speed up */ 602 list_for_each_entry(e, &ife->metalist, metalist) { 603 if (metaid == e->metaid) { 604 if (e->ops) { 605 /* We check for decode presence already */ 606 return e->ops->decode(skb, mdata, mlen); 607 } 608 } 609 } 610 611 return 0; 612 } 613 614 struct ifeheadr { 615 __be16 metalen; 616 u8 tlv_data[]; 617 }; 618 619 struct meta_tlvhdr { 620 __be16 type; 621 __be16 len; 622 }; 623 624 static int tcf_ife_decode(struct sk_buff *skb, const struct tc_action *a, 625 struct tcf_result *res) 626 { 627 struct tcf_ife_info *ife = a->priv; 628 int action = ife->tcf_action; 629 struct ifeheadr *ifehdr = (struct ifeheadr *)skb->data; 630 u16 ifehdrln = ifehdr->metalen; 631 struct meta_tlvhdr *tlv = (struct meta_tlvhdr *)(ifehdr->tlv_data); 632 633 spin_lock(&ife->tcf_lock); 634 bstats_update(&ife->tcf_bstats, skb); 635 ife->tcf_tm.lastuse = jiffies; 636 spin_unlock(&ife->tcf_lock); 637 638 ifehdrln = ntohs(ifehdrln); 639 if (unlikely(!pskb_may_pull(skb, ifehdrln))) { 640 spin_lock(&ife->tcf_lock); 641 ife->tcf_qstats.drops++; 642 spin_unlock(&ife->tcf_lock); 643 return TC_ACT_SHOT; 644 } 645 646 skb_set_mac_header(skb, ifehdrln); 647 __skb_pull(skb, ifehdrln); 648 skb->protocol = eth_type_trans(skb, skb->dev); 649 ifehdrln -= IFE_METAHDRLEN; 650 651 while (ifehdrln > 0) { 652 u8 *tlvdata = (u8 *)tlv; 653 u16 mtype = tlv->type; 654 u16 mlen = tlv->len; 655 656 mtype = ntohs(mtype); 657 mlen = ntohs(mlen); 658 659 if (find_decode_metaid(skb, ife, mtype, (mlen - 4), 660 (void *)(tlvdata + 4))) { 661 /* abuse overlimits to count when we receive metadata 662 * but dont have an ops for it 663 */ 664 pr_info_ratelimited("Unknown metaid %d alnlen %d\n", 665 mtype, mlen); 666 ife->tcf_qstats.overlimits++; 667 } 668 669 tlvdata += mlen; 670 ifehdrln -= mlen; 671 tlv = (struct meta_tlvhdr *)tlvdata; 672 } 673 674 skb_reset_network_header(skb); 675 return action; 676 } 677 678 /*XXX: check if we can do this at install time instead of current 679 * send data path 680 **/ 681 static int ife_get_sz(struct sk_buff *skb, struct tcf_ife_info *ife) 682 { 683 struct tcf_meta_info *e, *n; 684 int tot_run_sz = 0, run_sz = 0; 685 686 list_for_each_entry_safe(e, n, &ife->metalist, metalist) { 687 if (e->ops->check_presence) { 688 run_sz = e->ops->check_presence(skb, e); 689 tot_run_sz += run_sz; 690 } 691 } 692 693 return tot_run_sz; 694 } 695 696 static int tcf_ife_encode(struct sk_buff *skb, const struct tc_action *a, 697 struct tcf_result *res) 698 { 699 struct tcf_ife_info *ife = a->priv; 700 int action = ife->tcf_action; 701 struct ethhdr *oethh; /* outer ether header */ 702 struct ethhdr *iethh; /* inner eth header */ 703 struct tcf_meta_info *e; 704 /* 705 OUTERHDR:TOTMETALEN:{TLVHDR:Metadatum:TLVHDR..}:ORIGDATA 706 where ORIGDATA = original ethernet header ... 707 */ 708 u16 metalen = ife_get_sz(skb, ife); 709 int hdrm = metalen + skb->dev->hard_header_len + IFE_METAHDRLEN; 710 unsigned int skboff = skb->dev->hard_header_len; 711 u32 at = G_TC_AT(skb->tc_verd); 712 int new_len = skb->len + hdrm; 713 bool exceed_mtu = false; 714 int err; 715 716 if (at & AT_EGRESS) { 717 if (new_len > skb->dev->mtu) 718 exceed_mtu = true; 719 } 720 721 spin_lock(&ife->tcf_lock); 722 bstats_update(&ife->tcf_bstats, skb); 723 ife->tcf_tm.lastuse = jiffies; 724 725 if (!metalen) { /* no metadata to send */ 726 /* abuse overlimits to count when we allow packet 727 * with no metadata 728 */ 729 ife->tcf_qstats.overlimits++; 730 spin_unlock(&ife->tcf_lock); 731 return action; 732 } 733 /* could be stupid policy setup or mtu config 734 * so lets be conservative.. */ 735 if ((action == TC_ACT_SHOT) || exceed_mtu) { 736 ife->tcf_qstats.drops++; 737 spin_unlock(&ife->tcf_lock); 738 return TC_ACT_SHOT; 739 } 740 741 iethh = eth_hdr(skb); 742 743 err = skb_cow_head(skb, hdrm); 744 if (unlikely(err)) { 745 ife->tcf_qstats.drops++; 746 spin_unlock(&ife->tcf_lock); 747 return TC_ACT_SHOT; 748 } 749 750 if (!(at & AT_EGRESS)) 751 skb_push(skb, skb->dev->hard_header_len); 752 753 __skb_push(skb, hdrm); 754 memcpy(skb->data, iethh, skb->mac_len); 755 skb_reset_mac_header(skb); 756 oethh = eth_hdr(skb); 757 758 /*total metadata length */ 759 metalen += IFE_METAHDRLEN; 760 metalen = htons(metalen); 761 memcpy((skb->data + skboff), &metalen, IFE_METAHDRLEN); 762 skboff += IFE_METAHDRLEN; 763 764 /* XXX: we dont have a clever way of telling encode to 765 * not repeat some of the computations that are done by 766 * ops->presence_check... 767 */ 768 list_for_each_entry(e, &ife->metalist, metalist) { 769 if (e->ops->encode) { 770 err = e->ops->encode(skb, (void *)(skb->data + skboff), 771 e); 772 } 773 if (err < 0) { 774 /* too corrupt to keep around if overwritten */ 775 ife->tcf_qstats.drops++; 776 spin_unlock(&ife->tcf_lock); 777 return TC_ACT_SHOT; 778 } 779 skboff += err; 780 } 781 782 if (!is_zero_ether_addr(ife->eth_src)) 783 ether_addr_copy(oethh->h_source, ife->eth_src); 784 else 785 ether_addr_copy(oethh->h_source, iethh->h_source); 786 if (!is_zero_ether_addr(ife->eth_dst)) 787 ether_addr_copy(oethh->h_dest, ife->eth_dst); 788 else 789 ether_addr_copy(oethh->h_dest, iethh->h_dest); 790 oethh->h_proto = htons(ife->eth_type); 791 792 if (!(at & AT_EGRESS)) 793 skb_pull(skb, skb->dev->hard_header_len); 794 795 spin_unlock(&ife->tcf_lock); 796 797 return action; 798 } 799 800 static int tcf_ife_act(struct sk_buff *skb, const struct tc_action *a, 801 struct tcf_result *res) 802 { 803 struct tcf_ife_info *ife = a->priv; 804 805 if (ife->flags & IFE_ENCODE) 806 return tcf_ife_encode(skb, a, res); 807 808 if (!(ife->flags & IFE_ENCODE)) 809 return tcf_ife_decode(skb, a, res); 810 811 pr_info_ratelimited("unknown failure(policy neither de/encode\n"); 812 spin_lock(&ife->tcf_lock); 813 bstats_update(&ife->tcf_bstats, skb); 814 ife->tcf_tm.lastuse = jiffies; 815 ife->tcf_qstats.drops++; 816 spin_unlock(&ife->tcf_lock); 817 818 return TC_ACT_SHOT; 819 } 820 821 static int tcf_ife_walker(struct net *net, struct sk_buff *skb, 822 struct netlink_callback *cb, int type, 823 struct tc_action *a) 824 { 825 struct tc_action_net *tn = net_generic(net, ife_net_id); 826 827 return tcf_generic_walker(tn, skb, cb, type, a); 828 } 829 830 static int tcf_ife_search(struct net *net, struct tc_action *a, u32 index) 831 { 832 struct tc_action_net *tn = net_generic(net, ife_net_id); 833 834 return tcf_hash_search(tn, a, index); 835 } 836 837 static struct tc_action_ops act_ife_ops = { 838 .kind = "ife", 839 .type = TCA_ACT_IFE, 840 .owner = THIS_MODULE, 841 .act = tcf_ife_act, 842 .dump = tcf_ife_dump, 843 .cleanup = tcf_ife_cleanup, 844 .init = tcf_ife_init, 845 .walk = tcf_ife_walker, 846 .lookup = tcf_ife_search, 847 }; 848 849 static __net_init int ife_init_net(struct net *net) 850 { 851 struct tc_action_net *tn = net_generic(net, ife_net_id); 852 853 return tc_action_net_init(tn, &act_ife_ops, IFE_TAB_MASK); 854 } 855 856 static void __net_exit ife_exit_net(struct net *net) 857 { 858 struct tc_action_net *tn = net_generic(net, ife_net_id); 859 860 tc_action_net_exit(tn); 861 } 862 863 static struct pernet_operations ife_net_ops = { 864 .init = ife_init_net, 865 .exit = ife_exit_net, 866 .id = &ife_net_id, 867 .size = sizeof(struct tc_action_net), 868 }; 869 870 static int __init ife_init_module(void) 871 { 872 return tcf_register_action(&act_ife_ops, &ife_net_ops); 873 } 874 875 static void __exit ife_cleanup_module(void) 876 { 877 tcf_unregister_action(&act_ife_ops, &ife_net_ops); 878 } 879 880 module_init(ife_init_module); 881 module_exit(ife_cleanup_module); 882 883 MODULE_AUTHOR("Jamal Hadi Salim(2015)"); 884 MODULE_DESCRIPTION("Inter-FE LFB action"); 885 MODULE_LICENSE("GPL"); 886