1 /* 2 * net/sched/em_meta.c Metadata ematch 3 * 4 * This program is free software; you can redistribute it and/or 5 * modify it under the terms of the GNU General Public License 6 * as published by the Free Software Foundation; either version 7 * 2 of the License, or (at your option) any later version. 8 * 9 * Authors: Thomas Graf <tgraf@suug.ch> 10 * 11 * ========================================================================== 12 * 13 * The metadata ematch compares two meta objects where each object 14 * represents either a meta value stored in the kernel or a static 15 * value provided by userspace. The objects are not provided by 16 * userspace itself but rather a definition providing the information 17 * to build them. Every object is of a certain type which must be 18 * equal to the object it is being compared to. 19 * 20 * The definition of a objects conists of the type (meta type), a 21 * identifier (meta id) and additional type specific information. 22 * The meta id is either TCF_META_TYPE_VALUE for values provided by 23 * userspace or a index to the meta operations table consisting of 24 * function pointers to type specific meta data collectors returning 25 * the value of the requested meta value. 26 * 27 * lvalue rvalue 28 * +-----------+ +-----------+ 29 * | type: INT | | type: INT | 30 * def | id: DEV | | id: VALUE | 31 * | data: | | data: 3 | 32 * +-----------+ +-----------+ 33 * | | 34 * ---> meta_ops[INT][DEV](...) | 35 * | | 36 * ----------- | 37 * V V 38 * +-----------+ +-----------+ 39 * | type: INT | | type: INT | 40 * obj | id: DEV | | id: VALUE | 41 * | data: 2 |<--data got filled out | data: 3 | 42 * +-----------+ +-----------+ 43 * | | 44 * --------------> 2 equals 3 <-------------- 45 * 46 * This is a simplified schema, the complexity varies depending 47 * on the meta type. Obviously, the length of the data must also 48 * be provided for non-numeric types. 49 * 50 * Additionally, type dependent modifiers such as shift operators 51 * or mask may be applied to extend the functionaliy. As of now, 52 * the variable length type supports shifting the byte string to 53 * the right, eating up any number of octets and thus supporting 54 * wildcard interface name comparisons such as "ppp%" matching 55 * ppp0..9. 56 * 57 * NOTE: Certain meta values depend on other subsystems and are 58 * only available if that subsystem is enabled in the kernel. 59 */ 60 61 #include <linux/slab.h> 62 #include <linux/module.h> 63 #include <linux/types.h> 64 #include <linux/kernel.h> 65 #include <linux/sched.h> 66 #include <linux/string.h> 67 #include <linux/skbuff.h> 68 #include <linux/random.h> 69 #include <linux/if_vlan.h> 70 #include <linux/tc_ematch/tc_em_meta.h> 71 #include <net/dst.h> 72 #include <net/route.h> 73 #include <net/pkt_cls.h> 74 #include <net/sock.h> 75 76 struct meta_obj { 77 unsigned long value; 78 unsigned int len; 79 }; 80 81 struct meta_value { 82 struct tcf_meta_val hdr; 83 unsigned long val; 84 unsigned int len; 85 }; 86 87 struct meta_match { 88 struct meta_value lvalue; 89 struct meta_value rvalue; 90 }; 91 92 static inline int meta_id(struct meta_value *v) 93 { 94 return TCF_META_ID(v->hdr.kind); 95 } 96 97 static inline int meta_type(struct meta_value *v) 98 { 99 return TCF_META_TYPE(v->hdr.kind); 100 } 101 102 #define META_COLLECTOR(FUNC) static void meta_##FUNC(struct sk_buff *skb, \ 103 struct tcf_pkt_info *info, struct meta_value *v, \ 104 struct meta_obj *dst, int *err) 105 106 /************************************************************************** 107 * System status & misc 108 **************************************************************************/ 109 110 META_COLLECTOR(int_random) 111 { 112 get_random_bytes(&dst->value, sizeof(dst->value)); 113 } 114 115 static inline unsigned long fixed_loadavg(int load) 116 { 117 int rnd_load = load + (FIXED_1/200); 118 int rnd_frac = ((rnd_load & (FIXED_1-1)) * 100) >> FSHIFT; 119 120 return ((rnd_load >> FSHIFT) * 100) + rnd_frac; 121 } 122 123 META_COLLECTOR(int_loadavg_0) 124 { 125 dst->value = fixed_loadavg(avenrun[0]); 126 } 127 128 META_COLLECTOR(int_loadavg_1) 129 { 130 dst->value = fixed_loadavg(avenrun[1]); 131 } 132 133 META_COLLECTOR(int_loadavg_2) 134 { 135 dst->value = fixed_loadavg(avenrun[2]); 136 } 137 138 /************************************************************************** 139 * Device names & indices 140 **************************************************************************/ 141 142 static inline int int_dev(struct net_device *dev, struct meta_obj *dst) 143 { 144 if (unlikely(dev == NULL)) 145 return -1; 146 147 dst->value = dev->ifindex; 148 return 0; 149 } 150 151 static inline int var_dev(struct net_device *dev, struct meta_obj *dst) 152 { 153 if (unlikely(dev == NULL)) 154 return -1; 155 156 dst->value = (unsigned long) dev->name; 157 dst->len = strlen(dev->name); 158 return 0; 159 } 160 161 META_COLLECTOR(int_dev) 162 { 163 *err = int_dev(skb->dev, dst); 164 } 165 166 META_COLLECTOR(var_dev) 167 { 168 *err = var_dev(skb->dev, dst); 169 } 170 171 /************************************************************************** 172 * vlan tag 173 **************************************************************************/ 174 175 META_COLLECTOR(int_vlan_tag) 176 { 177 unsigned short tag; 178 179 tag = skb_vlan_tag_get(skb); 180 if (!tag && __vlan_get_tag(skb, &tag)) 181 *err = -1; 182 else 183 dst->value = tag; 184 } 185 186 187 188 /************************************************************************** 189 * skb attributes 190 **************************************************************************/ 191 192 META_COLLECTOR(int_priority) 193 { 194 dst->value = skb->priority; 195 } 196 197 META_COLLECTOR(int_protocol) 198 { 199 /* Let userspace take care of the byte ordering */ 200 dst->value = tc_skb_protocol(skb); 201 } 202 203 META_COLLECTOR(int_pkttype) 204 { 205 dst->value = skb->pkt_type; 206 } 207 208 META_COLLECTOR(int_pktlen) 209 { 210 dst->value = skb->len; 211 } 212 213 META_COLLECTOR(int_datalen) 214 { 215 dst->value = skb->data_len; 216 } 217 218 META_COLLECTOR(int_maclen) 219 { 220 dst->value = skb->mac_len; 221 } 222 223 META_COLLECTOR(int_rxhash) 224 { 225 dst->value = skb_get_hash(skb); 226 } 227 228 /************************************************************************** 229 * Netfilter 230 **************************************************************************/ 231 232 META_COLLECTOR(int_mark) 233 { 234 dst->value = skb->mark; 235 } 236 237 /************************************************************************** 238 * Traffic Control 239 **************************************************************************/ 240 241 META_COLLECTOR(int_tcindex) 242 { 243 dst->value = skb->tc_index; 244 } 245 246 /************************************************************************** 247 * Routing 248 **************************************************************************/ 249 250 META_COLLECTOR(int_rtclassid) 251 { 252 if (unlikely(skb_dst(skb) == NULL)) 253 *err = -1; 254 else 255 #ifdef CONFIG_IP_ROUTE_CLASSID 256 dst->value = skb_dst(skb)->tclassid; 257 #else 258 dst->value = 0; 259 #endif 260 } 261 262 META_COLLECTOR(int_rtiif) 263 { 264 if (unlikely(skb_rtable(skb) == NULL)) 265 *err = -1; 266 else 267 dst->value = inet_iif(skb); 268 } 269 270 /************************************************************************** 271 * Socket Attributes 272 **************************************************************************/ 273 274 #define skip_nonlocal(skb) \ 275 (unlikely(skb->sk == NULL)) 276 277 META_COLLECTOR(int_sk_family) 278 { 279 if (skip_nonlocal(skb)) { 280 *err = -1; 281 return; 282 } 283 dst->value = skb->sk->sk_family; 284 } 285 286 META_COLLECTOR(int_sk_state) 287 { 288 if (skip_nonlocal(skb)) { 289 *err = -1; 290 return; 291 } 292 dst->value = skb->sk->sk_state; 293 } 294 295 META_COLLECTOR(int_sk_reuse) 296 { 297 if (skip_nonlocal(skb)) { 298 *err = -1; 299 return; 300 } 301 dst->value = skb->sk->sk_reuse; 302 } 303 304 META_COLLECTOR(int_sk_bound_if) 305 { 306 if (skip_nonlocal(skb)) { 307 *err = -1; 308 return; 309 } 310 /* No error if bound_dev_if is 0, legal userspace check */ 311 dst->value = skb->sk->sk_bound_dev_if; 312 } 313 314 META_COLLECTOR(var_sk_bound_if) 315 { 316 if (skip_nonlocal(skb)) { 317 *err = -1; 318 return; 319 } 320 321 if (skb->sk->sk_bound_dev_if == 0) { 322 dst->value = (unsigned long) "any"; 323 dst->len = 3; 324 } else { 325 struct net_device *dev; 326 327 rcu_read_lock(); 328 dev = dev_get_by_index_rcu(sock_net(skb->sk), 329 skb->sk->sk_bound_dev_if); 330 *err = var_dev(dev, dst); 331 rcu_read_unlock(); 332 } 333 } 334 335 META_COLLECTOR(int_sk_refcnt) 336 { 337 if (skip_nonlocal(skb)) { 338 *err = -1; 339 return; 340 } 341 dst->value = atomic_read(&skb->sk->sk_refcnt); 342 } 343 344 META_COLLECTOR(int_sk_rcvbuf) 345 { 346 const struct sock *sk = skb_to_full_sk(skb); 347 348 if (!sk) { 349 *err = -1; 350 return; 351 } 352 dst->value = sk->sk_rcvbuf; 353 } 354 355 META_COLLECTOR(int_sk_shutdown) 356 { 357 const struct sock *sk = skb_to_full_sk(skb); 358 359 if (!sk) { 360 *err = -1; 361 return; 362 } 363 dst->value = sk->sk_shutdown; 364 } 365 366 META_COLLECTOR(int_sk_proto) 367 { 368 const struct sock *sk = skb_to_full_sk(skb); 369 370 if (!sk) { 371 *err = -1; 372 return; 373 } 374 dst->value = sk->sk_protocol; 375 } 376 377 META_COLLECTOR(int_sk_type) 378 { 379 const struct sock *sk = skb_to_full_sk(skb); 380 381 if (!sk) { 382 *err = -1; 383 return; 384 } 385 dst->value = sk->sk_type; 386 } 387 388 META_COLLECTOR(int_sk_rmem_alloc) 389 { 390 const struct sock *sk = skb_to_full_sk(skb); 391 392 if (!sk) { 393 *err = -1; 394 return; 395 } 396 dst->value = sk_rmem_alloc_get(sk); 397 } 398 399 META_COLLECTOR(int_sk_wmem_alloc) 400 { 401 const struct sock *sk = skb_to_full_sk(skb); 402 403 if (!sk) { 404 *err = -1; 405 return; 406 } 407 dst->value = sk_wmem_alloc_get(sk); 408 } 409 410 META_COLLECTOR(int_sk_omem_alloc) 411 { 412 const struct sock *sk = skb_to_full_sk(skb); 413 414 if (!sk) { 415 *err = -1; 416 return; 417 } 418 dst->value = atomic_read(&sk->sk_omem_alloc); 419 } 420 421 META_COLLECTOR(int_sk_rcv_qlen) 422 { 423 const struct sock *sk = skb_to_full_sk(skb); 424 425 if (!sk) { 426 *err = -1; 427 return; 428 } 429 dst->value = sk->sk_receive_queue.qlen; 430 } 431 432 META_COLLECTOR(int_sk_snd_qlen) 433 { 434 const struct sock *sk = skb_to_full_sk(skb); 435 436 if (!sk) { 437 *err = -1; 438 return; 439 } 440 dst->value = sk->sk_write_queue.qlen; 441 } 442 443 META_COLLECTOR(int_sk_wmem_queued) 444 { 445 const struct sock *sk = skb_to_full_sk(skb); 446 447 if (!sk) { 448 *err = -1; 449 return; 450 } 451 dst->value = sk->sk_wmem_queued; 452 } 453 454 META_COLLECTOR(int_sk_fwd_alloc) 455 { 456 const struct sock *sk = skb_to_full_sk(skb); 457 458 if (!sk) { 459 *err = -1; 460 return; 461 } 462 dst->value = sk->sk_forward_alloc; 463 } 464 465 META_COLLECTOR(int_sk_sndbuf) 466 { 467 const struct sock *sk = skb_to_full_sk(skb); 468 469 if (!sk) { 470 *err = -1; 471 return; 472 } 473 dst->value = sk->sk_sndbuf; 474 } 475 476 META_COLLECTOR(int_sk_alloc) 477 { 478 const struct sock *sk = skb_to_full_sk(skb); 479 480 if (!sk) { 481 *err = -1; 482 return; 483 } 484 dst->value = (__force int) sk->sk_allocation; 485 } 486 487 META_COLLECTOR(int_sk_hash) 488 { 489 if (skip_nonlocal(skb)) { 490 *err = -1; 491 return; 492 } 493 dst->value = skb->sk->sk_hash; 494 } 495 496 META_COLLECTOR(int_sk_lingertime) 497 { 498 const struct sock *sk = skb_to_full_sk(skb); 499 500 if (!sk) { 501 *err = -1; 502 return; 503 } 504 dst->value = sk->sk_lingertime / HZ; 505 } 506 507 META_COLLECTOR(int_sk_err_qlen) 508 { 509 const struct sock *sk = skb_to_full_sk(skb); 510 511 if (!sk) { 512 *err = -1; 513 return; 514 } 515 dst->value = sk->sk_error_queue.qlen; 516 } 517 518 META_COLLECTOR(int_sk_ack_bl) 519 { 520 const struct sock *sk = skb_to_full_sk(skb); 521 522 if (!sk) { 523 *err = -1; 524 return; 525 } 526 dst->value = sk->sk_ack_backlog; 527 } 528 529 META_COLLECTOR(int_sk_max_ack_bl) 530 { 531 const struct sock *sk = skb_to_full_sk(skb); 532 533 if (!sk) { 534 *err = -1; 535 return; 536 } 537 dst->value = sk->sk_max_ack_backlog; 538 } 539 540 META_COLLECTOR(int_sk_prio) 541 { 542 const struct sock *sk = skb_to_full_sk(skb); 543 544 if (!sk) { 545 *err = -1; 546 return; 547 } 548 dst->value = sk->sk_priority; 549 } 550 551 META_COLLECTOR(int_sk_rcvlowat) 552 { 553 const struct sock *sk = skb_to_full_sk(skb); 554 555 if (!sk) { 556 *err = -1; 557 return; 558 } 559 dst->value = sk->sk_rcvlowat; 560 } 561 562 META_COLLECTOR(int_sk_rcvtimeo) 563 { 564 const struct sock *sk = skb_to_full_sk(skb); 565 566 if (!sk) { 567 *err = -1; 568 return; 569 } 570 dst->value = sk->sk_rcvtimeo / HZ; 571 } 572 573 META_COLLECTOR(int_sk_sndtimeo) 574 { 575 const struct sock *sk = skb_to_full_sk(skb); 576 577 if (!sk) { 578 *err = -1; 579 return; 580 } 581 dst->value = sk->sk_sndtimeo / HZ; 582 } 583 584 META_COLLECTOR(int_sk_sendmsg_off) 585 { 586 const struct sock *sk = skb_to_full_sk(skb); 587 588 if (!sk) { 589 *err = -1; 590 return; 591 } 592 dst->value = sk->sk_frag.offset; 593 } 594 595 META_COLLECTOR(int_sk_write_pend) 596 { 597 const struct sock *sk = skb_to_full_sk(skb); 598 599 if (!sk) { 600 *err = -1; 601 return; 602 } 603 dst->value = sk->sk_write_pending; 604 } 605 606 /************************************************************************** 607 * Meta value collectors assignment table 608 **************************************************************************/ 609 610 struct meta_ops { 611 void (*get)(struct sk_buff *, struct tcf_pkt_info *, 612 struct meta_value *, struct meta_obj *, int *); 613 }; 614 615 #define META_ID(name) TCF_META_ID_##name 616 #define META_FUNC(name) { .get = meta_##name } 617 618 /* Meta value operations table listing all meta value collectors and 619 * assigns them to a type and meta id. */ 620 static struct meta_ops __meta_ops[TCF_META_TYPE_MAX + 1][TCF_META_ID_MAX + 1] = { 621 [TCF_META_TYPE_VAR] = { 622 [META_ID(DEV)] = META_FUNC(var_dev), 623 [META_ID(SK_BOUND_IF)] = META_FUNC(var_sk_bound_if), 624 }, 625 [TCF_META_TYPE_INT] = { 626 [META_ID(RANDOM)] = META_FUNC(int_random), 627 [META_ID(LOADAVG_0)] = META_FUNC(int_loadavg_0), 628 [META_ID(LOADAVG_1)] = META_FUNC(int_loadavg_1), 629 [META_ID(LOADAVG_2)] = META_FUNC(int_loadavg_2), 630 [META_ID(DEV)] = META_FUNC(int_dev), 631 [META_ID(PRIORITY)] = META_FUNC(int_priority), 632 [META_ID(PROTOCOL)] = META_FUNC(int_protocol), 633 [META_ID(PKTTYPE)] = META_FUNC(int_pkttype), 634 [META_ID(PKTLEN)] = META_FUNC(int_pktlen), 635 [META_ID(DATALEN)] = META_FUNC(int_datalen), 636 [META_ID(MACLEN)] = META_FUNC(int_maclen), 637 [META_ID(NFMARK)] = META_FUNC(int_mark), 638 [META_ID(TCINDEX)] = META_FUNC(int_tcindex), 639 [META_ID(RTCLASSID)] = META_FUNC(int_rtclassid), 640 [META_ID(RTIIF)] = META_FUNC(int_rtiif), 641 [META_ID(SK_FAMILY)] = META_FUNC(int_sk_family), 642 [META_ID(SK_STATE)] = META_FUNC(int_sk_state), 643 [META_ID(SK_REUSE)] = META_FUNC(int_sk_reuse), 644 [META_ID(SK_BOUND_IF)] = META_FUNC(int_sk_bound_if), 645 [META_ID(SK_REFCNT)] = META_FUNC(int_sk_refcnt), 646 [META_ID(SK_RCVBUF)] = META_FUNC(int_sk_rcvbuf), 647 [META_ID(SK_SNDBUF)] = META_FUNC(int_sk_sndbuf), 648 [META_ID(SK_SHUTDOWN)] = META_FUNC(int_sk_shutdown), 649 [META_ID(SK_PROTO)] = META_FUNC(int_sk_proto), 650 [META_ID(SK_TYPE)] = META_FUNC(int_sk_type), 651 [META_ID(SK_RMEM_ALLOC)] = META_FUNC(int_sk_rmem_alloc), 652 [META_ID(SK_WMEM_ALLOC)] = META_FUNC(int_sk_wmem_alloc), 653 [META_ID(SK_OMEM_ALLOC)] = META_FUNC(int_sk_omem_alloc), 654 [META_ID(SK_WMEM_QUEUED)] = META_FUNC(int_sk_wmem_queued), 655 [META_ID(SK_RCV_QLEN)] = META_FUNC(int_sk_rcv_qlen), 656 [META_ID(SK_SND_QLEN)] = META_FUNC(int_sk_snd_qlen), 657 [META_ID(SK_ERR_QLEN)] = META_FUNC(int_sk_err_qlen), 658 [META_ID(SK_FORWARD_ALLOCS)] = META_FUNC(int_sk_fwd_alloc), 659 [META_ID(SK_ALLOCS)] = META_FUNC(int_sk_alloc), 660 [META_ID(SK_HASH)] = META_FUNC(int_sk_hash), 661 [META_ID(SK_LINGERTIME)] = META_FUNC(int_sk_lingertime), 662 [META_ID(SK_ACK_BACKLOG)] = META_FUNC(int_sk_ack_bl), 663 [META_ID(SK_MAX_ACK_BACKLOG)] = META_FUNC(int_sk_max_ack_bl), 664 [META_ID(SK_PRIO)] = META_FUNC(int_sk_prio), 665 [META_ID(SK_RCVLOWAT)] = META_FUNC(int_sk_rcvlowat), 666 [META_ID(SK_RCVTIMEO)] = META_FUNC(int_sk_rcvtimeo), 667 [META_ID(SK_SNDTIMEO)] = META_FUNC(int_sk_sndtimeo), 668 [META_ID(SK_SENDMSG_OFF)] = META_FUNC(int_sk_sendmsg_off), 669 [META_ID(SK_WRITE_PENDING)] = META_FUNC(int_sk_write_pend), 670 [META_ID(VLAN_TAG)] = META_FUNC(int_vlan_tag), 671 [META_ID(RXHASH)] = META_FUNC(int_rxhash), 672 } 673 }; 674 675 static inline struct meta_ops *meta_ops(struct meta_value *val) 676 { 677 return &__meta_ops[meta_type(val)][meta_id(val)]; 678 } 679 680 /************************************************************************** 681 * Type specific operations for TCF_META_TYPE_VAR 682 **************************************************************************/ 683 684 static int meta_var_compare(struct meta_obj *a, struct meta_obj *b) 685 { 686 int r = a->len - b->len; 687 688 if (r == 0) 689 r = memcmp((void *) a->value, (void *) b->value, a->len); 690 691 return r; 692 } 693 694 static int meta_var_change(struct meta_value *dst, struct nlattr *nla) 695 { 696 int len = nla_len(nla); 697 698 dst->val = (unsigned long)kmemdup(nla_data(nla), len, GFP_KERNEL); 699 if (dst->val == 0UL) 700 return -ENOMEM; 701 dst->len = len; 702 return 0; 703 } 704 705 static void meta_var_destroy(struct meta_value *v) 706 { 707 kfree((void *) v->val); 708 } 709 710 static void meta_var_apply_extras(struct meta_value *v, 711 struct meta_obj *dst) 712 { 713 int shift = v->hdr.shift; 714 715 if (shift && shift < dst->len) 716 dst->len -= shift; 717 } 718 719 static int meta_var_dump(struct sk_buff *skb, struct meta_value *v, int tlv) 720 { 721 if (v->val && v->len && 722 nla_put(skb, tlv, v->len, (void *) v->val)) 723 goto nla_put_failure; 724 return 0; 725 726 nla_put_failure: 727 return -1; 728 } 729 730 /************************************************************************** 731 * Type specific operations for TCF_META_TYPE_INT 732 **************************************************************************/ 733 734 static int meta_int_compare(struct meta_obj *a, struct meta_obj *b) 735 { 736 /* Let gcc optimize it, the unlikely is not really based on 737 * some numbers but jump free code for mismatches seems 738 * more logical. */ 739 if (unlikely(a->value == b->value)) 740 return 0; 741 else if (a->value < b->value) 742 return -1; 743 else 744 return 1; 745 } 746 747 static int meta_int_change(struct meta_value *dst, struct nlattr *nla) 748 { 749 if (nla_len(nla) >= sizeof(unsigned long)) { 750 dst->val = *(unsigned long *) nla_data(nla); 751 dst->len = sizeof(unsigned long); 752 } else if (nla_len(nla) == sizeof(u32)) { 753 dst->val = nla_get_u32(nla); 754 dst->len = sizeof(u32); 755 } else 756 return -EINVAL; 757 758 return 0; 759 } 760 761 static void meta_int_apply_extras(struct meta_value *v, 762 struct meta_obj *dst) 763 { 764 if (v->hdr.shift) 765 dst->value >>= v->hdr.shift; 766 767 if (v->val) 768 dst->value &= v->val; 769 } 770 771 static int meta_int_dump(struct sk_buff *skb, struct meta_value *v, int tlv) 772 { 773 if (v->len == sizeof(unsigned long)) { 774 if (nla_put(skb, tlv, sizeof(unsigned long), &v->val)) 775 goto nla_put_failure; 776 } else if (v->len == sizeof(u32)) { 777 if (nla_put_u32(skb, tlv, v->val)) 778 goto nla_put_failure; 779 } 780 781 return 0; 782 783 nla_put_failure: 784 return -1; 785 } 786 787 /************************************************************************** 788 * Type specific operations table 789 **************************************************************************/ 790 791 struct meta_type_ops { 792 void (*destroy)(struct meta_value *); 793 int (*compare)(struct meta_obj *, struct meta_obj *); 794 int (*change)(struct meta_value *, struct nlattr *); 795 void (*apply_extras)(struct meta_value *, struct meta_obj *); 796 int (*dump)(struct sk_buff *, struct meta_value *, int); 797 }; 798 799 static struct meta_type_ops __meta_type_ops[TCF_META_TYPE_MAX + 1] = { 800 [TCF_META_TYPE_VAR] = { 801 .destroy = meta_var_destroy, 802 .compare = meta_var_compare, 803 .change = meta_var_change, 804 .apply_extras = meta_var_apply_extras, 805 .dump = meta_var_dump 806 }, 807 [TCF_META_TYPE_INT] = { 808 .compare = meta_int_compare, 809 .change = meta_int_change, 810 .apply_extras = meta_int_apply_extras, 811 .dump = meta_int_dump 812 } 813 }; 814 815 static inline struct meta_type_ops *meta_type_ops(struct meta_value *v) 816 { 817 return &__meta_type_ops[meta_type(v)]; 818 } 819 820 /************************************************************************** 821 * Core 822 **************************************************************************/ 823 824 static int meta_get(struct sk_buff *skb, struct tcf_pkt_info *info, 825 struct meta_value *v, struct meta_obj *dst) 826 { 827 int err = 0; 828 829 if (meta_id(v) == TCF_META_ID_VALUE) { 830 dst->value = v->val; 831 dst->len = v->len; 832 return 0; 833 } 834 835 meta_ops(v)->get(skb, info, v, dst, &err); 836 if (err < 0) 837 return err; 838 839 if (meta_type_ops(v)->apply_extras) 840 meta_type_ops(v)->apply_extras(v, dst); 841 842 return 0; 843 } 844 845 static int em_meta_match(struct sk_buff *skb, struct tcf_ematch *m, 846 struct tcf_pkt_info *info) 847 { 848 int r; 849 struct meta_match *meta = (struct meta_match *) m->data; 850 struct meta_obj l_value, r_value; 851 852 if (meta_get(skb, info, &meta->lvalue, &l_value) < 0 || 853 meta_get(skb, info, &meta->rvalue, &r_value) < 0) 854 return 0; 855 856 r = meta_type_ops(&meta->lvalue)->compare(&l_value, &r_value); 857 858 switch (meta->lvalue.hdr.op) { 859 case TCF_EM_OPND_EQ: 860 return !r; 861 case TCF_EM_OPND_LT: 862 return r < 0; 863 case TCF_EM_OPND_GT: 864 return r > 0; 865 } 866 867 return 0; 868 } 869 870 static void meta_delete(struct meta_match *meta) 871 { 872 if (meta) { 873 struct meta_type_ops *ops = meta_type_ops(&meta->lvalue); 874 875 if (ops && ops->destroy) { 876 ops->destroy(&meta->lvalue); 877 ops->destroy(&meta->rvalue); 878 } 879 } 880 881 kfree(meta); 882 } 883 884 static inline int meta_change_data(struct meta_value *dst, struct nlattr *nla) 885 { 886 if (nla) { 887 if (nla_len(nla) == 0) 888 return -EINVAL; 889 890 return meta_type_ops(dst)->change(dst, nla); 891 } 892 893 return 0; 894 } 895 896 static inline int meta_is_supported(struct meta_value *val) 897 { 898 return !meta_id(val) || meta_ops(val)->get; 899 } 900 901 static const struct nla_policy meta_policy[TCA_EM_META_MAX + 1] = { 902 [TCA_EM_META_HDR] = { .len = sizeof(struct tcf_meta_hdr) }, 903 }; 904 905 static int em_meta_change(struct net *net, void *data, int len, 906 struct tcf_ematch *m) 907 { 908 int err; 909 struct nlattr *tb[TCA_EM_META_MAX + 1]; 910 struct tcf_meta_hdr *hdr; 911 struct meta_match *meta = NULL; 912 913 err = nla_parse(tb, TCA_EM_META_MAX, data, len, meta_policy); 914 if (err < 0) 915 goto errout; 916 917 err = -EINVAL; 918 if (tb[TCA_EM_META_HDR] == NULL) 919 goto errout; 920 hdr = nla_data(tb[TCA_EM_META_HDR]); 921 922 if (TCF_META_TYPE(hdr->left.kind) != TCF_META_TYPE(hdr->right.kind) || 923 TCF_META_TYPE(hdr->left.kind) > TCF_META_TYPE_MAX || 924 TCF_META_ID(hdr->left.kind) > TCF_META_ID_MAX || 925 TCF_META_ID(hdr->right.kind) > TCF_META_ID_MAX) 926 goto errout; 927 928 meta = kzalloc(sizeof(*meta), GFP_KERNEL); 929 if (meta == NULL) { 930 err = -ENOMEM; 931 goto errout; 932 } 933 934 memcpy(&meta->lvalue.hdr, &hdr->left, sizeof(hdr->left)); 935 memcpy(&meta->rvalue.hdr, &hdr->right, sizeof(hdr->right)); 936 937 if (!meta_is_supported(&meta->lvalue) || 938 !meta_is_supported(&meta->rvalue)) { 939 err = -EOPNOTSUPP; 940 goto errout; 941 } 942 943 if (meta_change_data(&meta->lvalue, tb[TCA_EM_META_LVALUE]) < 0 || 944 meta_change_data(&meta->rvalue, tb[TCA_EM_META_RVALUE]) < 0) 945 goto errout; 946 947 m->datalen = sizeof(*meta); 948 m->data = (unsigned long) meta; 949 950 err = 0; 951 errout: 952 if (err && meta) 953 meta_delete(meta); 954 return err; 955 } 956 957 static void em_meta_destroy(struct tcf_ematch *m) 958 { 959 if (m) 960 meta_delete((struct meta_match *) m->data); 961 } 962 963 static int em_meta_dump(struct sk_buff *skb, struct tcf_ematch *em) 964 { 965 struct meta_match *meta = (struct meta_match *) em->data; 966 struct tcf_meta_hdr hdr; 967 struct meta_type_ops *ops; 968 969 memset(&hdr, 0, sizeof(hdr)); 970 memcpy(&hdr.left, &meta->lvalue.hdr, sizeof(hdr.left)); 971 memcpy(&hdr.right, &meta->rvalue.hdr, sizeof(hdr.right)); 972 973 if (nla_put(skb, TCA_EM_META_HDR, sizeof(hdr), &hdr)) 974 goto nla_put_failure; 975 976 ops = meta_type_ops(&meta->lvalue); 977 if (ops->dump(skb, &meta->lvalue, TCA_EM_META_LVALUE) < 0 || 978 ops->dump(skb, &meta->rvalue, TCA_EM_META_RVALUE) < 0) 979 goto nla_put_failure; 980 981 return 0; 982 983 nla_put_failure: 984 return -1; 985 } 986 987 static struct tcf_ematch_ops em_meta_ops = { 988 .kind = TCF_EM_META, 989 .change = em_meta_change, 990 .match = em_meta_match, 991 .destroy = em_meta_destroy, 992 .dump = em_meta_dump, 993 .owner = THIS_MODULE, 994 .link = LIST_HEAD_INIT(em_meta_ops.link) 995 }; 996 997 static int __init init_em_meta(void) 998 { 999 return tcf_em_register(&em_meta_ops); 1000 } 1001 1002 static void __exit exit_em_meta(void) 1003 { 1004 tcf_em_unregister(&em_meta_ops); 1005 } 1006 1007 MODULE_LICENSE("GPL"); 1008 1009 module_init(init_em_meta); 1010 module_exit(exit_em_meta); 1011 1012 MODULE_ALIAS_TCF_EMATCH(TCF_EM_META); 1013