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 * Additionaly, type dependant 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 { 78 unsigned long value; 79 unsigned int len; 80 }; 81 82 struct meta_value 83 { 84 struct tcf_meta_val hdr; 85 unsigned long val; 86 unsigned int len; 87 }; 88 89 struct meta_match 90 { 91 struct meta_value lvalue; 92 struct meta_value rvalue; 93 }; 94 95 static inline int meta_id(struct meta_value *v) 96 { 97 return TCF_META_ID(v->hdr.kind); 98 } 99 100 static inline int meta_type(struct meta_value *v) 101 { 102 return TCF_META_TYPE(v->hdr.kind); 103 } 104 105 #define META_COLLECTOR(FUNC) static void meta_##FUNC(struct sk_buff *skb, \ 106 struct tcf_pkt_info *info, struct meta_value *v, \ 107 struct meta_obj *dst, int *err) 108 109 /************************************************************************** 110 * System status & misc 111 **************************************************************************/ 112 113 META_COLLECTOR(int_random) 114 { 115 get_random_bytes(&dst->value, sizeof(dst->value)); 116 } 117 118 static inline unsigned long fixed_loadavg(int load) 119 { 120 int rnd_load = load + (FIXED_1/200); 121 int rnd_frac = ((rnd_load & (FIXED_1-1)) * 100) >> FSHIFT; 122 123 return ((rnd_load >> FSHIFT) * 100) + rnd_frac; 124 } 125 126 META_COLLECTOR(int_loadavg_0) 127 { 128 dst->value = fixed_loadavg(avenrun[0]); 129 } 130 131 META_COLLECTOR(int_loadavg_1) 132 { 133 dst->value = fixed_loadavg(avenrun[1]); 134 } 135 136 META_COLLECTOR(int_loadavg_2) 137 { 138 dst->value = fixed_loadavg(avenrun[2]); 139 } 140 141 /************************************************************************** 142 * Device names & indices 143 **************************************************************************/ 144 145 static inline int int_dev(struct net_device *dev, struct meta_obj *dst) 146 { 147 if (unlikely(dev == NULL)) 148 return -1; 149 150 dst->value = dev->ifindex; 151 return 0; 152 } 153 154 static inline int var_dev(struct net_device *dev, struct meta_obj *dst) 155 { 156 if (unlikely(dev == NULL)) 157 return -1; 158 159 dst->value = (unsigned long) dev->name; 160 dst->len = strlen(dev->name); 161 return 0; 162 } 163 164 META_COLLECTOR(int_dev) 165 { 166 *err = int_dev(skb->dev, dst); 167 } 168 169 META_COLLECTOR(var_dev) 170 { 171 *err = var_dev(skb->dev, dst); 172 } 173 174 /************************************************************************** 175 * vlan tag 176 **************************************************************************/ 177 178 META_COLLECTOR(int_vlan_tag) 179 { 180 unsigned short tag; 181 182 tag = vlan_tx_tag_get(skb); 183 if (!tag && __vlan_get_tag(skb, &tag)) 184 *err = -1; 185 else 186 dst->value = tag; 187 } 188 189 190 191 /************************************************************************** 192 * skb attributes 193 **************************************************************************/ 194 195 META_COLLECTOR(int_priority) 196 { 197 dst->value = skb->priority; 198 } 199 200 META_COLLECTOR(int_protocol) 201 { 202 /* Let userspace take care of the byte ordering */ 203 dst->value = skb->protocol; 204 } 205 206 META_COLLECTOR(int_pkttype) 207 { 208 dst->value = skb->pkt_type; 209 } 210 211 META_COLLECTOR(int_pktlen) 212 { 213 dst->value = skb->len; 214 } 215 216 META_COLLECTOR(int_datalen) 217 { 218 dst->value = skb->data_len; 219 } 220 221 META_COLLECTOR(int_maclen) 222 { 223 dst->value = skb->mac_len; 224 } 225 226 /************************************************************************** 227 * Netfilter 228 **************************************************************************/ 229 230 META_COLLECTOR(int_mark) 231 { 232 dst->value = skb->mark; 233 } 234 235 /************************************************************************** 236 * Traffic Control 237 **************************************************************************/ 238 239 META_COLLECTOR(int_tcindex) 240 { 241 dst->value = skb->tc_index; 242 } 243 244 /************************************************************************** 245 * Routing 246 **************************************************************************/ 247 248 META_COLLECTOR(int_rtclassid) 249 { 250 if (unlikely(skb_dst(skb) == NULL)) 251 *err = -1; 252 else 253 #ifdef CONFIG_NET_CLS_ROUTE 254 dst->value = skb_dst(skb)->tclassid; 255 #else 256 dst->value = 0; 257 #endif 258 } 259 260 META_COLLECTOR(int_rtiif) 261 { 262 if (unlikely(skb_rtable(skb) == NULL)) 263 *err = -1; 264 else 265 dst->value = skb_rtable(skb)->fl.iif; 266 } 267 268 /************************************************************************** 269 * Socket Attributes 270 **************************************************************************/ 271 272 #define SKIP_NONLOCAL(skb) \ 273 if (unlikely(skb->sk == NULL)) { \ 274 *err = -1; \ 275 return; \ 276 } 277 278 META_COLLECTOR(int_sk_family) 279 { 280 SKIP_NONLOCAL(skb); 281 dst->value = skb->sk->sk_family; 282 } 283 284 META_COLLECTOR(int_sk_state) 285 { 286 SKIP_NONLOCAL(skb); 287 dst->value = skb->sk->sk_state; 288 } 289 290 META_COLLECTOR(int_sk_reuse) 291 { 292 SKIP_NONLOCAL(skb); 293 dst->value = skb->sk->sk_reuse; 294 } 295 296 META_COLLECTOR(int_sk_bound_if) 297 { 298 SKIP_NONLOCAL(skb); 299 /* No error if bound_dev_if is 0, legal userspace check */ 300 dst->value = skb->sk->sk_bound_dev_if; 301 } 302 303 META_COLLECTOR(var_sk_bound_if) 304 { 305 SKIP_NONLOCAL(skb); 306 307 if (skb->sk->sk_bound_dev_if == 0) { 308 dst->value = (unsigned long) "any"; 309 dst->len = 3; 310 } else { 311 struct net_device *dev; 312 313 rcu_read_lock(); 314 dev = dev_get_by_index_rcu(sock_net(skb->sk), 315 skb->sk->sk_bound_dev_if); 316 *err = var_dev(dev, dst); 317 rcu_read_unlock(); 318 } 319 } 320 321 META_COLLECTOR(int_sk_refcnt) 322 { 323 SKIP_NONLOCAL(skb); 324 dst->value = atomic_read(&skb->sk->sk_refcnt); 325 } 326 327 META_COLLECTOR(int_sk_rcvbuf) 328 { 329 SKIP_NONLOCAL(skb); 330 dst->value = skb->sk->sk_rcvbuf; 331 } 332 333 META_COLLECTOR(int_sk_shutdown) 334 { 335 SKIP_NONLOCAL(skb); 336 dst->value = skb->sk->sk_shutdown; 337 } 338 339 META_COLLECTOR(int_sk_proto) 340 { 341 SKIP_NONLOCAL(skb); 342 dst->value = skb->sk->sk_protocol; 343 } 344 345 META_COLLECTOR(int_sk_type) 346 { 347 SKIP_NONLOCAL(skb); 348 dst->value = skb->sk->sk_type; 349 } 350 351 META_COLLECTOR(int_sk_rmem_alloc) 352 { 353 SKIP_NONLOCAL(skb); 354 dst->value = sk_rmem_alloc_get(skb->sk); 355 } 356 357 META_COLLECTOR(int_sk_wmem_alloc) 358 { 359 SKIP_NONLOCAL(skb); 360 dst->value = sk_wmem_alloc_get(skb->sk); 361 } 362 363 META_COLLECTOR(int_sk_omem_alloc) 364 { 365 SKIP_NONLOCAL(skb); 366 dst->value = atomic_read(&skb->sk->sk_omem_alloc); 367 } 368 369 META_COLLECTOR(int_sk_rcv_qlen) 370 { 371 SKIP_NONLOCAL(skb); 372 dst->value = skb->sk->sk_receive_queue.qlen; 373 } 374 375 META_COLLECTOR(int_sk_snd_qlen) 376 { 377 SKIP_NONLOCAL(skb); 378 dst->value = skb->sk->sk_write_queue.qlen; 379 } 380 381 META_COLLECTOR(int_sk_wmem_queued) 382 { 383 SKIP_NONLOCAL(skb); 384 dst->value = skb->sk->sk_wmem_queued; 385 } 386 387 META_COLLECTOR(int_sk_fwd_alloc) 388 { 389 SKIP_NONLOCAL(skb); 390 dst->value = skb->sk->sk_forward_alloc; 391 } 392 393 META_COLLECTOR(int_sk_sndbuf) 394 { 395 SKIP_NONLOCAL(skb); 396 dst->value = skb->sk->sk_sndbuf; 397 } 398 399 META_COLLECTOR(int_sk_alloc) 400 { 401 SKIP_NONLOCAL(skb); 402 dst->value = skb->sk->sk_allocation; 403 } 404 405 META_COLLECTOR(int_sk_route_caps) 406 { 407 SKIP_NONLOCAL(skb); 408 dst->value = skb->sk->sk_route_caps; 409 } 410 411 META_COLLECTOR(int_sk_hash) 412 { 413 SKIP_NONLOCAL(skb); 414 dst->value = skb->sk->sk_hash; 415 } 416 417 META_COLLECTOR(int_sk_lingertime) 418 { 419 SKIP_NONLOCAL(skb); 420 dst->value = skb->sk->sk_lingertime / HZ; 421 } 422 423 META_COLLECTOR(int_sk_err_qlen) 424 { 425 SKIP_NONLOCAL(skb); 426 dst->value = skb->sk->sk_error_queue.qlen; 427 } 428 429 META_COLLECTOR(int_sk_ack_bl) 430 { 431 SKIP_NONLOCAL(skb); 432 dst->value = skb->sk->sk_ack_backlog; 433 } 434 435 META_COLLECTOR(int_sk_max_ack_bl) 436 { 437 SKIP_NONLOCAL(skb); 438 dst->value = skb->sk->sk_max_ack_backlog; 439 } 440 441 META_COLLECTOR(int_sk_prio) 442 { 443 SKIP_NONLOCAL(skb); 444 dst->value = skb->sk->sk_priority; 445 } 446 447 META_COLLECTOR(int_sk_rcvlowat) 448 { 449 SKIP_NONLOCAL(skb); 450 dst->value = skb->sk->sk_rcvlowat; 451 } 452 453 META_COLLECTOR(int_sk_rcvtimeo) 454 { 455 SKIP_NONLOCAL(skb); 456 dst->value = skb->sk->sk_rcvtimeo / HZ; 457 } 458 459 META_COLLECTOR(int_sk_sndtimeo) 460 { 461 SKIP_NONLOCAL(skb); 462 dst->value = skb->sk->sk_sndtimeo / HZ; 463 } 464 465 META_COLLECTOR(int_sk_sendmsg_off) 466 { 467 SKIP_NONLOCAL(skb); 468 dst->value = skb->sk->sk_sndmsg_off; 469 } 470 471 META_COLLECTOR(int_sk_write_pend) 472 { 473 SKIP_NONLOCAL(skb); 474 dst->value = skb->sk->sk_write_pending; 475 } 476 477 /************************************************************************** 478 * Meta value collectors assignment table 479 **************************************************************************/ 480 481 struct meta_ops 482 { 483 void (*get)(struct sk_buff *, struct tcf_pkt_info *, 484 struct meta_value *, struct meta_obj *, int *); 485 }; 486 487 #define META_ID(name) TCF_META_ID_##name 488 #define META_FUNC(name) { .get = meta_##name } 489 490 /* Meta value operations table listing all meta value collectors and 491 * assigns them to a type and meta id. */ 492 static struct meta_ops __meta_ops[TCF_META_TYPE_MAX+1][TCF_META_ID_MAX+1] = { 493 [TCF_META_TYPE_VAR] = { 494 [META_ID(DEV)] = META_FUNC(var_dev), 495 [META_ID(SK_BOUND_IF)] = META_FUNC(var_sk_bound_if), 496 }, 497 [TCF_META_TYPE_INT] = { 498 [META_ID(RANDOM)] = META_FUNC(int_random), 499 [META_ID(LOADAVG_0)] = META_FUNC(int_loadavg_0), 500 [META_ID(LOADAVG_1)] = META_FUNC(int_loadavg_1), 501 [META_ID(LOADAVG_2)] = META_FUNC(int_loadavg_2), 502 [META_ID(DEV)] = META_FUNC(int_dev), 503 [META_ID(PRIORITY)] = META_FUNC(int_priority), 504 [META_ID(PROTOCOL)] = META_FUNC(int_protocol), 505 [META_ID(PKTTYPE)] = META_FUNC(int_pkttype), 506 [META_ID(PKTLEN)] = META_FUNC(int_pktlen), 507 [META_ID(DATALEN)] = META_FUNC(int_datalen), 508 [META_ID(MACLEN)] = META_FUNC(int_maclen), 509 [META_ID(NFMARK)] = META_FUNC(int_mark), 510 [META_ID(TCINDEX)] = META_FUNC(int_tcindex), 511 [META_ID(RTCLASSID)] = META_FUNC(int_rtclassid), 512 [META_ID(RTIIF)] = META_FUNC(int_rtiif), 513 [META_ID(SK_FAMILY)] = META_FUNC(int_sk_family), 514 [META_ID(SK_STATE)] = META_FUNC(int_sk_state), 515 [META_ID(SK_REUSE)] = META_FUNC(int_sk_reuse), 516 [META_ID(SK_BOUND_IF)] = META_FUNC(int_sk_bound_if), 517 [META_ID(SK_REFCNT)] = META_FUNC(int_sk_refcnt), 518 [META_ID(SK_RCVBUF)] = META_FUNC(int_sk_rcvbuf), 519 [META_ID(SK_SNDBUF)] = META_FUNC(int_sk_sndbuf), 520 [META_ID(SK_SHUTDOWN)] = META_FUNC(int_sk_shutdown), 521 [META_ID(SK_PROTO)] = META_FUNC(int_sk_proto), 522 [META_ID(SK_TYPE)] = META_FUNC(int_sk_type), 523 [META_ID(SK_RMEM_ALLOC)] = META_FUNC(int_sk_rmem_alloc), 524 [META_ID(SK_WMEM_ALLOC)] = META_FUNC(int_sk_wmem_alloc), 525 [META_ID(SK_OMEM_ALLOC)] = META_FUNC(int_sk_omem_alloc), 526 [META_ID(SK_WMEM_QUEUED)] = META_FUNC(int_sk_wmem_queued), 527 [META_ID(SK_RCV_QLEN)] = META_FUNC(int_sk_rcv_qlen), 528 [META_ID(SK_SND_QLEN)] = META_FUNC(int_sk_snd_qlen), 529 [META_ID(SK_ERR_QLEN)] = META_FUNC(int_sk_err_qlen), 530 [META_ID(SK_FORWARD_ALLOCS)] = META_FUNC(int_sk_fwd_alloc), 531 [META_ID(SK_ALLOCS)] = META_FUNC(int_sk_alloc), 532 [META_ID(SK_ROUTE_CAPS)] = META_FUNC(int_sk_route_caps), 533 [META_ID(SK_HASH)] = META_FUNC(int_sk_hash), 534 [META_ID(SK_LINGERTIME)] = META_FUNC(int_sk_lingertime), 535 [META_ID(SK_ACK_BACKLOG)] = META_FUNC(int_sk_ack_bl), 536 [META_ID(SK_MAX_ACK_BACKLOG)] = META_FUNC(int_sk_max_ack_bl), 537 [META_ID(SK_PRIO)] = META_FUNC(int_sk_prio), 538 [META_ID(SK_RCVLOWAT)] = META_FUNC(int_sk_rcvlowat), 539 [META_ID(SK_RCVTIMEO)] = META_FUNC(int_sk_rcvtimeo), 540 [META_ID(SK_SNDTIMEO)] = META_FUNC(int_sk_sndtimeo), 541 [META_ID(SK_SENDMSG_OFF)] = META_FUNC(int_sk_sendmsg_off), 542 [META_ID(SK_WRITE_PENDING)] = META_FUNC(int_sk_write_pend), 543 [META_ID(VLAN_TAG)] = META_FUNC(int_vlan_tag), 544 } 545 }; 546 547 static inline struct meta_ops * meta_ops(struct meta_value *val) 548 { 549 return &__meta_ops[meta_type(val)][meta_id(val)]; 550 } 551 552 /************************************************************************** 553 * Type specific operations for TCF_META_TYPE_VAR 554 **************************************************************************/ 555 556 static int meta_var_compare(struct meta_obj *a, struct meta_obj *b) 557 { 558 int r = a->len - b->len; 559 560 if (r == 0) 561 r = memcmp((void *) a->value, (void *) b->value, a->len); 562 563 return r; 564 } 565 566 static int meta_var_change(struct meta_value *dst, struct nlattr *nla) 567 { 568 int len = nla_len(nla); 569 570 dst->val = (unsigned long)kmemdup(nla_data(nla), len, GFP_KERNEL); 571 if (dst->val == 0UL) 572 return -ENOMEM; 573 dst->len = len; 574 return 0; 575 } 576 577 static void meta_var_destroy(struct meta_value *v) 578 { 579 kfree((void *) v->val); 580 } 581 582 static void meta_var_apply_extras(struct meta_value *v, 583 struct meta_obj *dst) 584 { 585 int shift = v->hdr.shift; 586 587 if (shift && shift < dst->len) 588 dst->len -= shift; 589 } 590 591 static int meta_var_dump(struct sk_buff *skb, struct meta_value *v, int tlv) 592 { 593 if (v->val && v->len) 594 NLA_PUT(skb, tlv, v->len, (void *) v->val); 595 return 0; 596 597 nla_put_failure: 598 return -1; 599 } 600 601 /************************************************************************** 602 * Type specific operations for TCF_META_TYPE_INT 603 **************************************************************************/ 604 605 static int meta_int_compare(struct meta_obj *a, struct meta_obj *b) 606 { 607 /* Let gcc optimize it, the unlikely is not really based on 608 * some numbers but jump free code for mismatches seems 609 * more logical. */ 610 if (unlikely(a->value == b->value)) 611 return 0; 612 else if (a->value < b->value) 613 return -1; 614 else 615 return 1; 616 } 617 618 static int meta_int_change(struct meta_value *dst, struct nlattr *nla) 619 { 620 if (nla_len(nla) >= sizeof(unsigned long)) { 621 dst->val = *(unsigned long *) nla_data(nla); 622 dst->len = sizeof(unsigned long); 623 } else if (nla_len(nla) == sizeof(u32)) { 624 dst->val = nla_get_u32(nla); 625 dst->len = sizeof(u32); 626 } else 627 return -EINVAL; 628 629 return 0; 630 } 631 632 static void meta_int_apply_extras(struct meta_value *v, 633 struct meta_obj *dst) 634 { 635 if (v->hdr.shift) 636 dst->value >>= v->hdr.shift; 637 638 if (v->val) 639 dst->value &= v->val; 640 } 641 642 static int meta_int_dump(struct sk_buff *skb, struct meta_value *v, int tlv) 643 { 644 if (v->len == sizeof(unsigned long)) 645 NLA_PUT(skb, tlv, sizeof(unsigned long), &v->val); 646 else if (v->len == sizeof(u32)) { 647 NLA_PUT_U32(skb, tlv, v->val); 648 } 649 650 return 0; 651 652 nla_put_failure: 653 return -1; 654 } 655 656 /************************************************************************** 657 * Type specific operations table 658 **************************************************************************/ 659 660 struct meta_type_ops 661 { 662 void (*destroy)(struct meta_value *); 663 int (*compare)(struct meta_obj *, struct meta_obj *); 664 int (*change)(struct meta_value *, struct nlattr *); 665 void (*apply_extras)(struct meta_value *, struct meta_obj *); 666 int (*dump)(struct sk_buff *, struct meta_value *, int); 667 }; 668 669 static struct meta_type_ops __meta_type_ops[TCF_META_TYPE_MAX+1] = { 670 [TCF_META_TYPE_VAR] = { 671 .destroy = meta_var_destroy, 672 .compare = meta_var_compare, 673 .change = meta_var_change, 674 .apply_extras = meta_var_apply_extras, 675 .dump = meta_var_dump 676 }, 677 [TCF_META_TYPE_INT] = { 678 .compare = meta_int_compare, 679 .change = meta_int_change, 680 .apply_extras = meta_int_apply_extras, 681 .dump = meta_int_dump 682 } 683 }; 684 685 static inline struct meta_type_ops * meta_type_ops(struct meta_value *v) 686 { 687 return &__meta_type_ops[meta_type(v)]; 688 } 689 690 /************************************************************************** 691 * Core 692 **************************************************************************/ 693 694 static int meta_get(struct sk_buff *skb, struct tcf_pkt_info *info, 695 struct meta_value *v, struct meta_obj *dst) 696 { 697 int err = 0; 698 699 if (meta_id(v) == TCF_META_ID_VALUE) { 700 dst->value = v->val; 701 dst->len = v->len; 702 return 0; 703 } 704 705 meta_ops(v)->get(skb, info, v, dst, &err); 706 if (err < 0) 707 return err; 708 709 if (meta_type_ops(v)->apply_extras) 710 meta_type_ops(v)->apply_extras(v, dst); 711 712 return 0; 713 } 714 715 static int em_meta_match(struct sk_buff *skb, struct tcf_ematch *m, 716 struct tcf_pkt_info *info) 717 { 718 int r; 719 struct meta_match *meta = (struct meta_match *) m->data; 720 struct meta_obj l_value, r_value; 721 722 if (meta_get(skb, info, &meta->lvalue, &l_value) < 0 || 723 meta_get(skb, info, &meta->rvalue, &r_value) < 0) 724 return 0; 725 726 r = meta_type_ops(&meta->lvalue)->compare(&l_value, &r_value); 727 728 switch (meta->lvalue.hdr.op) { 729 case TCF_EM_OPND_EQ: 730 return !r; 731 case TCF_EM_OPND_LT: 732 return r < 0; 733 case TCF_EM_OPND_GT: 734 return r > 0; 735 } 736 737 return 0; 738 } 739 740 static void meta_delete(struct meta_match *meta) 741 { 742 if (meta) { 743 struct meta_type_ops *ops = meta_type_ops(&meta->lvalue); 744 745 if (ops && ops->destroy) { 746 ops->destroy(&meta->lvalue); 747 ops->destroy(&meta->rvalue); 748 } 749 } 750 751 kfree(meta); 752 } 753 754 static inline int meta_change_data(struct meta_value *dst, struct nlattr *nla) 755 { 756 if (nla) { 757 if (nla_len(nla) == 0) 758 return -EINVAL; 759 760 return meta_type_ops(dst)->change(dst, nla); 761 } 762 763 return 0; 764 } 765 766 static inline int meta_is_supported(struct meta_value *val) 767 { 768 return (!meta_id(val) || meta_ops(val)->get); 769 } 770 771 static const struct nla_policy meta_policy[TCA_EM_META_MAX + 1] = { 772 [TCA_EM_META_HDR] = { .len = sizeof(struct tcf_meta_hdr) }, 773 }; 774 775 static int em_meta_change(struct tcf_proto *tp, void *data, int len, 776 struct tcf_ematch *m) 777 { 778 int err; 779 struct nlattr *tb[TCA_EM_META_MAX + 1]; 780 struct tcf_meta_hdr *hdr; 781 struct meta_match *meta = NULL; 782 783 err = nla_parse(tb, TCA_EM_META_MAX, data, len, meta_policy); 784 if (err < 0) 785 goto errout; 786 787 err = -EINVAL; 788 if (tb[TCA_EM_META_HDR] == NULL) 789 goto errout; 790 hdr = nla_data(tb[TCA_EM_META_HDR]); 791 792 if (TCF_META_TYPE(hdr->left.kind) != TCF_META_TYPE(hdr->right.kind) || 793 TCF_META_TYPE(hdr->left.kind) > TCF_META_TYPE_MAX || 794 TCF_META_ID(hdr->left.kind) > TCF_META_ID_MAX || 795 TCF_META_ID(hdr->right.kind) > TCF_META_ID_MAX) 796 goto errout; 797 798 meta = kzalloc(sizeof(*meta), GFP_KERNEL); 799 if (meta == NULL) 800 goto errout; 801 802 memcpy(&meta->lvalue.hdr, &hdr->left, sizeof(hdr->left)); 803 memcpy(&meta->rvalue.hdr, &hdr->right, sizeof(hdr->right)); 804 805 if (!meta_is_supported(&meta->lvalue) || 806 !meta_is_supported(&meta->rvalue)) { 807 err = -EOPNOTSUPP; 808 goto errout; 809 } 810 811 if (meta_change_data(&meta->lvalue, tb[TCA_EM_META_LVALUE]) < 0 || 812 meta_change_data(&meta->rvalue, tb[TCA_EM_META_RVALUE]) < 0) 813 goto errout; 814 815 m->datalen = sizeof(*meta); 816 m->data = (unsigned long) meta; 817 818 err = 0; 819 errout: 820 if (err && meta) 821 meta_delete(meta); 822 return err; 823 } 824 825 static void em_meta_destroy(struct tcf_proto *tp, struct tcf_ematch *m) 826 { 827 if (m) 828 meta_delete((struct meta_match *) m->data); 829 } 830 831 static int em_meta_dump(struct sk_buff *skb, struct tcf_ematch *em) 832 { 833 struct meta_match *meta = (struct meta_match *) em->data; 834 struct tcf_meta_hdr hdr; 835 struct meta_type_ops *ops; 836 837 memset(&hdr, 0, sizeof(hdr)); 838 memcpy(&hdr.left, &meta->lvalue.hdr, sizeof(hdr.left)); 839 memcpy(&hdr.right, &meta->rvalue.hdr, sizeof(hdr.right)); 840 841 NLA_PUT(skb, TCA_EM_META_HDR, sizeof(hdr), &hdr); 842 843 ops = meta_type_ops(&meta->lvalue); 844 if (ops->dump(skb, &meta->lvalue, TCA_EM_META_LVALUE) < 0 || 845 ops->dump(skb, &meta->rvalue, TCA_EM_META_RVALUE) < 0) 846 goto nla_put_failure; 847 848 return 0; 849 850 nla_put_failure: 851 return -1; 852 } 853 854 static struct tcf_ematch_ops em_meta_ops = { 855 .kind = TCF_EM_META, 856 .change = em_meta_change, 857 .match = em_meta_match, 858 .destroy = em_meta_destroy, 859 .dump = em_meta_dump, 860 .owner = THIS_MODULE, 861 .link = LIST_HEAD_INIT(em_meta_ops.link) 862 }; 863 864 static int __init init_em_meta(void) 865 { 866 return tcf_em_register(&em_meta_ops); 867 } 868 869 static void __exit exit_em_meta(void) 870 { 871 tcf_em_unregister(&em_meta_ops); 872 } 873 874 MODULE_LICENSE("GPL"); 875 876 module_init(init_em_meta); 877 module_exit(exit_em_meta); 878 879 MODULE_ALIAS_TCF_EMATCH(TCF_EM_META); 880