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 subsytem is enabled in the kernel. 59 */ 60 61 #include <linux/config.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/tc_ematch/tc_em_meta.h> 70 #include <net/dst.h> 71 #include <net/route.h> 72 #include <net/pkt_cls.h> 73 #include <net/sock.h> 74 75 struct meta_obj 76 { 77 unsigned long value; 78 unsigned int len; 79 }; 80 81 struct meta_value 82 { 83 struct tcf_meta_val hdr; 84 unsigned long val; 85 unsigned int len; 86 }; 87 88 struct meta_match 89 { 90 struct meta_value lvalue; 91 struct meta_value rvalue; 92 }; 93 94 static inline int meta_id(struct meta_value *v) 95 { 96 return TCF_META_ID(v->hdr.kind); 97 } 98 99 static inline int meta_type(struct meta_value *v) 100 { 101 return TCF_META_TYPE(v->hdr.kind); 102 } 103 104 #define META_COLLECTOR(FUNC) static void meta_##FUNC(struct sk_buff *skb, \ 105 struct tcf_pkt_info *info, struct meta_value *v, \ 106 struct meta_obj *dst, int *err) 107 108 /************************************************************************** 109 * System status & misc 110 **************************************************************************/ 111 112 META_COLLECTOR(int_random) 113 { 114 get_random_bytes(&dst->value, sizeof(dst->value)); 115 } 116 117 static inline unsigned long fixed_loadavg(int load) 118 { 119 int rnd_load = load + (FIXED_1/200); 120 int rnd_frac = ((rnd_load & (FIXED_1-1)) * 100) >> FSHIFT; 121 122 return ((rnd_load >> FSHIFT) * 100) + rnd_frac; 123 } 124 125 META_COLLECTOR(int_loadavg_0) 126 { 127 dst->value = fixed_loadavg(avenrun[0]); 128 } 129 130 META_COLLECTOR(int_loadavg_1) 131 { 132 dst->value = fixed_loadavg(avenrun[1]); 133 } 134 135 META_COLLECTOR(int_loadavg_2) 136 { 137 dst->value = fixed_loadavg(avenrun[2]); 138 } 139 140 /************************************************************************** 141 * Device names & indices 142 **************************************************************************/ 143 144 static inline int int_dev(struct net_device *dev, struct meta_obj *dst) 145 { 146 if (unlikely(dev == NULL)) 147 return -1; 148 149 dst->value = dev->ifindex; 150 return 0; 151 } 152 153 static inline int var_dev(struct net_device *dev, struct meta_obj *dst) 154 { 155 if (unlikely(dev == NULL)) 156 return -1; 157 158 dst->value = (unsigned long) dev->name; 159 dst->len = strlen(dev->name); 160 return 0; 161 } 162 163 META_COLLECTOR(int_dev) 164 { 165 *err = int_dev(skb->dev, dst); 166 } 167 168 META_COLLECTOR(var_dev) 169 { 170 *err = var_dev(skb->dev, dst); 171 } 172 173 /************************************************************************** 174 * skb attributes 175 **************************************************************************/ 176 177 META_COLLECTOR(int_priority) 178 { 179 dst->value = skb->priority; 180 } 181 182 META_COLLECTOR(int_protocol) 183 { 184 /* Let userspace take care of the byte ordering */ 185 dst->value = skb->protocol; 186 } 187 188 META_COLLECTOR(int_pkttype) 189 { 190 dst->value = skb->pkt_type; 191 } 192 193 META_COLLECTOR(int_pktlen) 194 { 195 dst->value = skb->len; 196 } 197 198 META_COLLECTOR(int_datalen) 199 { 200 dst->value = skb->data_len; 201 } 202 203 META_COLLECTOR(int_maclen) 204 { 205 dst->value = skb->mac_len; 206 } 207 208 /************************************************************************** 209 * Netfilter 210 **************************************************************************/ 211 212 META_COLLECTOR(int_nfmark) 213 { 214 #ifdef CONFIG_NETFILTER 215 dst->value = skb->nfmark; 216 #else 217 dst->value = 0; 218 #endif 219 } 220 221 /************************************************************************** 222 * Traffic Control 223 **************************************************************************/ 224 225 META_COLLECTOR(int_tcindex) 226 { 227 dst->value = skb->tc_index; 228 } 229 230 /************************************************************************** 231 * Routing 232 **************************************************************************/ 233 234 META_COLLECTOR(int_rtclassid) 235 { 236 if (unlikely(skb->dst == NULL)) 237 *err = -1; 238 else 239 #ifdef CONFIG_NET_CLS_ROUTE 240 dst->value = skb->dst->tclassid; 241 #else 242 dst->value = 0; 243 #endif 244 } 245 246 META_COLLECTOR(int_rtiif) 247 { 248 if (unlikely(skb->dst == NULL)) 249 *err = -1; 250 else 251 dst->value = ((struct rtable*) skb->dst)->fl.iif; 252 } 253 254 /************************************************************************** 255 * Socket Attributes 256 **************************************************************************/ 257 258 #define SKIP_NONLOCAL(skb) \ 259 if (unlikely(skb->sk == NULL)) { \ 260 *err = -1; \ 261 return; \ 262 } 263 264 META_COLLECTOR(int_sk_family) 265 { 266 SKIP_NONLOCAL(skb); 267 dst->value = skb->sk->sk_family; 268 } 269 270 META_COLLECTOR(int_sk_state) 271 { 272 SKIP_NONLOCAL(skb); 273 dst->value = skb->sk->sk_state; 274 } 275 276 META_COLLECTOR(int_sk_reuse) 277 { 278 SKIP_NONLOCAL(skb); 279 dst->value = skb->sk->sk_reuse; 280 } 281 282 META_COLLECTOR(int_sk_bound_if) 283 { 284 SKIP_NONLOCAL(skb); 285 /* No error if bound_dev_if is 0, legal userspace check */ 286 dst->value = skb->sk->sk_bound_dev_if; 287 } 288 289 META_COLLECTOR(var_sk_bound_if) 290 { 291 SKIP_NONLOCAL(skb); 292 293 if (skb->sk->sk_bound_dev_if == 0) { 294 dst->value = (unsigned long) "any"; 295 dst->len = 3; 296 } else { 297 struct net_device *dev; 298 299 dev = dev_get_by_index(skb->sk->sk_bound_dev_if); 300 *err = var_dev(dev, dst); 301 if (dev) 302 dev_put(dev); 303 } 304 } 305 306 META_COLLECTOR(int_sk_refcnt) 307 { 308 SKIP_NONLOCAL(skb); 309 dst->value = atomic_read(&skb->sk->sk_refcnt); 310 } 311 312 META_COLLECTOR(int_sk_rcvbuf) 313 { 314 SKIP_NONLOCAL(skb); 315 dst->value = skb->sk->sk_rcvbuf; 316 } 317 318 META_COLLECTOR(int_sk_shutdown) 319 { 320 SKIP_NONLOCAL(skb); 321 dst->value = skb->sk->sk_shutdown; 322 } 323 324 META_COLLECTOR(int_sk_proto) 325 { 326 SKIP_NONLOCAL(skb); 327 dst->value = skb->sk->sk_protocol; 328 } 329 330 META_COLLECTOR(int_sk_type) 331 { 332 SKIP_NONLOCAL(skb); 333 dst->value = skb->sk->sk_type; 334 } 335 336 META_COLLECTOR(int_sk_rmem_alloc) 337 { 338 SKIP_NONLOCAL(skb); 339 dst->value = atomic_read(&skb->sk->sk_rmem_alloc); 340 } 341 342 META_COLLECTOR(int_sk_wmem_alloc) 343 { 344 SKIP_NONLOCAL(skb); 345 dst->value = atomic_read(&skb->sk->sk_wmem_alloc); 346 } 347 348 META_COLLECTOR(int_sk_omem_alloc) 349 { 350 SKIP_NONLOCAL(skb); 351 dst->value = atomic_read(&skb->sk->sk_omem_alloc); 352 } 353 354 META_COLLECTOR(int_sk_rcv_qlen) 355 { 356 SKIP_NONLOCAL(skb); 357 dst->value = skb->sk->sk_receive_queue.qlen; 358 } 359 360 META_COLLECTOR(int_sk_snd_qlen) 361 { 362 SKIP_NONLOCAL(skb); 363 dst->value = skb->sk->sk_write_queue.qlen; 364 } 365 366 META_COLLECTOR(int_sk_wmem_queued) 367 { 368 SKIP_NONLOCAL(skb); 369 dst->value = skb->sk->sk_wmem_queued; 370 } 371 372 META_COLLECTOR(int_sk_fwd_alloc) 373 { 374 SKIP_NONLOCAL(skb); 375 dst->value = skb->sk->sk_forward_alloc; 376 } 377 378 META_COLLECTOR(int_sk_sndbuf) 379 { 380 SKIP_NONLOCAL(skb); 381 dst->value = skb->sk->sk_sndbuf; 382 } 383 384 META_COLLECTOR(int_sk_alloc) 385 { 386 SKIP_NONLOCAL(skb); 387 dst->value = skb->sk->sk_allocation; 388 } 389 390 META_COLLECTOR(int_sk_route_caps) 391 { 392 SKIP_NONLOCAL(skb); 393 dst->value = skb->sk->sk_route_caps; 394 } 395 396 META_COLLECTOR(int_sk_hash) 397 { 398 SKIP_NONLOCAL(skb); 399 dst->value = skb->sk->sk_hash; 400 } 401 402 META_COLLECTOR(int_sk_lingertime) 403 { 404 SKIP_NONLOCAL(skb); 405 dst->value = skb->sk->sk_lingertime / HZ; 406 } 407 408 META_COLLECTOR(int_sk_err_qlen) 409 { 410 SKIP_NONLOCAL(skb); 411 dst->value = skb->sk->sk_error_queue.qlen; 412 } 413 414 META_COLLECTOR(int_sk_ack_bl) 415 { 416 SKIP_NONLOCAL(skb); 417 dst->value = skb->sk->sk_ack_backlog; 418 } 419 420 META_COLLECTOR(int_sk_max_ack_bl) 421 { 422 SKIP_NONLOCAL(skb); 423 dst->value = skb->sk->sk_max_ack_backlog; 424 } 425 426 META_COLLECTOR(int_sk_prio) 427 { 428 SKIP_NONLOCAL(skb); 429 dst->value = skb->sk->sk_priority; 430 } 431 432 META_COLLECTOR(int_sk_rcvlowat) 433 { 434 SKIP_NONLOCAL(skb); 435 dst->value = skb->sk->sk_rcvlowat; 436 } 437 438 META_COLLECTOR(int_sk_rcvtimeo) 439 { 440 SKIP_NONLOCAL(skb); 441 dst->value = skb->sk->sk_rcvtimeo / HZ; 442 } 443 444 META_COLLECTOR(int_sk_sndtimeo) 445 { 446 SKIP_NONLOCAL(skb); 447 dst->value = skb->sk->sk_sndtimeo / HZ; 448 } 449 450 META_COLLECTOR(int_sk_sendmsg_off) 451 { 452 SKIP_NONLOCAL(skb); 453 dst->value = skb->sk->sk_sndmsg_off; 454 } 455 456 META_COLLECTOR(int_sk_write_pend) 457 { 458 SKIP_NONLOCAL(skb); 459 dst->value = skb->sk->sk_write_pending; 460 } 461 462 /************************************************************************** 463 * Meta value collectors assignment table 464 **************************************************************************/ 465 466 struct meta_ops 467 { 468 void (*get)(struct sk_buff *, struct tcf_pkt_info *, 469 struct meta_value *, struct meta_obj *, int *); 470 }; 471 472 #define META_ID(name) TCF_META_ID_##name 473 #define META_FUNC(name) { .get = meta_##name } 474 475 /* Meta value operations table listing all meta value collectors and 476 * assigns them to a type and meta id. */ 477 static struct meta_ops __meta_ops[TCF_META_TYPE_MAX+1][TCF_META_ID_MAX+1] = { 478 [TCF_META_TYPE_VAR] = { 479 [META_ID(DEV)] = META_FUNC(var_dev), 480 [META_ID(SK_BOUND_IF)] = META_FUNC(var_sk_bound_if), 481 }, 482 [TCF_META_TYPE_INT] = { 483 [META_ID(RANDOM)] = META_FUNC(int_random), 484 [META_ID(LOADAVG_0)] = META_FUNC(int_loadavg_0), 485 [META_ID(LOADAVG_1)] = META_FUNC(int_loadavg_1), 486 [META_ID(LOADAVG_2)] = META_FUNC(int_loadavg_2), 487 [META_ID(DEV)] = META_FUNC(int_dev), 488 [META_ID(PRIORITY)] = META_FUNC(int_priority), 489 [META_ID(PROTOCOL)] = META_FUNC(int_protocol), 490 [META_ID(PKTTYPE)] = META_FUNC(int_pkttype), 491 [META_ID(PKTLEN)] = META_FUNC(int_pktlen), 492 [META_ID(DATALEN)] = META_FUNC(int_datalen), 493 [META_ID(MACLEN)] = META_FUNC(int_maclen), 494 [META_ID(NFMARK)] = META_FUNC(int_nfmark), 495 [META_ID(TCINDEX)] = META_FUNC(int_tcindex), 496 [META_ID(RTCLASSID)] = META_FUNC(int_rtclassid), 497 [META_ID(RTIIF)] = META_FUNC(int_rtiif), 498 [META_ID(SK_FAMILY)] = META_FUNC(int_sk_family), 499 [META_ID(SK_STATE)] = META_FUNC(int_sk_state), 500 [META_ID(SK_REUSE)] = META_FUNC(int_sk_reuse), 501 [META_ID(SK_BOUND_IF)] = META_FUNC(int_sk_bound_if), 502 [META_ID(SK_REFCNT)] = META_FUNC(int_sk_refcnt), 503 [META_ID(SK_RCVBUF)] = META_FUNC(int_sk_rcvbuf), 504 [META_ID(SK_SNDBUF)] = META_FUNC(int_sk_sndbuf), 505 [META_ID(SK_SHUTDOWN)] = META_FUNC(int_sk_shutdown), 506 [META_ID(SK_PROTO)] = META_FUNC(int_sk_proto), 507 [META_ID(SK_TYPE)] = META_FUNC(int_sk_type), 508 [META_ID(SK_RMEM_ALLOC)] = META_FUNC(int_sk_rmem_alloc), 509 [META_ID(SK_WMEM_ALLOC)] = META_FUNC(int_sk_wmem_alloc), 510 [META_ID(SK_OMEM_ALLOC)] = META_FUNC(int_sk_omem_alloc), 511 [META_ID(SK_WMEM_QUEUED)] = META_FUNC(int_sk_wmem_queued), 512 [META_ID(SK_RCV_QLEN)] = META_FUNC(int_sk_rcv_qlen), 513 [META_ID(SK_SND_QLEN)] = META_FUNC(int_sk_snd_qlen), 514 [META_ID(SK_ERR_QLEN)] = META_FUNC(int_sk_err_qlen), 515 [META_ID(SK_FORWARD_ALLOCS)] = META_FUNC(int_sk_fwd_alloc), 516 [META_ID(SK_ALLOCS)] = META_FUNC(int_sk_alloc), 517 [META_ID(SK_ROUTE_CAPS)] = META_FUNC(int_sk_route_caps), 518 [META_ID(SK_HASH)] = META_FUNC(int_sk_hash), 519 [META_ID(SK_LINGERTIME)] = META_FUNC(int_sk_lingertime), 520 [META_ID(SK_ACK_BACKLOG)] = META_FUNC(int_sk_ack_bl), 521 [META_ID(SK_MAX_ACK_BACKLOG)] = META_FUNC(int_sk_max_ack_bl), 522 [META_ID(SK_PRIO)] = META_FUNC(int_sk_prio), 523 [META_ID(SK_RCVLOWAT)] = META_FUNC(int_sk_rcvlowat), 524 [META_ID(SK_RCVTIMEO)] = META_FUNC(int_sk_rcvtimeo), 525 [META_ID(SK_SNDTIMEO)] = META_FUNC(int_sk_sndtimeo), 526 [META_ID(SK_SENDMSG_OFF)] = META_FUNC(int_sk_sendmsg_off), 527 [META_ID(SK_WRITE_PENDING)] = META_FUNC(int_sk_write_pend), 528 } 529 }; 530 531 static inline struct meta_ops * meta_ops(struct meta_value *val) 532 { 533 return &__meta_ops[meta_type(val)][meta_id(val)]; 534 } 535 536 /************************************************************************** 537 * Type specific operations for TCF_META_TYPE_VAR 538 **************************************************************************/ 539 540 static int meta_var_compare(struct meta_obj *a, struct meta_obj *b) 541 { 542 int r = a->len - b->len; 543 544 if (r == 0) 545 r = memcmp((void *) a->value, (void *) b->value, a->len); 546 547 return r; 548 } 549 550 static int meta_var_change(struct meta_value *dst, struct rtattr *rta) 551 { 552 int len = RTA_PAYLOAD(rta); 553 554 dst->val = (unsigned long) kmalloc(len, GFP_KERNEL); 555 if (dst->val == 0UL) 556 return -ENOMEM; 557 memcpy((void *) dst->val, RTA_DATA(rta), len); 558 dst->len = len; 559 return 0; 560 } 561 562 static void meta_var_destroy(struct meta_value *v) 563 { 564 kfree((void *) v->val); 565 } 566 567 static void meta_var_apply_extras(struct meta_value *v, 568 struct meta_obj *dst) 569 { 570 int shift = v->hdr.shift; 571 572 if (shift && shift < dst->len) 573 dst->len -= shift; 574 } 575 576 static int meta_var_dump(struct sk_buff *skb, struct meta_value *v, int tlv) 577 { 578 if (v->val && v->len) 579 RTA_PUT(skb, tlv, v->len, (void *) v->val); 580 return 0; 581 582 rtattr_failure: 583 return -1; 584 } 585 586 /************************************************************************** 587 * Type specific operations for TCF_META_TYPE_INT 588 **************************************************************************/ 589 590 static int meta_int_compare(struct meta_obj *a, struct meta_obj *b) 591 { 592 /* Let gcc optimize it, the unlikely is not really based on 593 * some numbers but jump free code for mismatches seems 594 * more logical. */ 595 if (unlikely(a->value == b->value)) 596 return 0; 597 else if (a->value < b->value) 598 return -1; 599 else 600 return 1; 601 } 602 603 static int meta_int_change(struct meta_value *dst, struct rtattr *rta) 604 { 605 if (RTA_PAYLOAD(rta) >= sizeof(unsigned long)) { 606 dst->val = *(unsigned long *) RTA_DATA(rta); 607 dst->len = sizeof(unsigned long); 608 } else if (RTA_PAYLOAD(rta) == sizeof(u32)) { 609 dst->val = *(u32 *) RTA_DATA(rta); 610 dst->len = sizeof(u32); 611 } else 612 return -EINVAL; 613 614 return 0; 615 } 616 617 static void meta_int_apply_extras(struct meta_value *v, 618 struct meta_obj *dst) 619 { 620 if (v->hdr.shift) 621 dst->value >>= v->hdr.shift; 622 623 if (v->val) 624 dst->value &= v->val; 625 } 626 627 static int meta_int_dump(struct sk_buff *skb, struct meta_value *v, int tlv) 628 { 629 if (v->len == sizeof(unsigned long)) 630 RTA_PUT(skb, tlv, sizeof(unsigned long), &v->val); 631 else if (v->len == sizeof(u32)) { 632 u32 d = v->val; 633 RTA_PUT(skb, tlv, sizeof(d), &d); 634 } 635 636 return 0; 637 638 rtattr_failure: 639 return -1; 640 } 641 642 /************************************************************************** 643 * Type specific operations table 644 **************************************************************************/ 645 646 struct meta_type_ops 647 { 648 void (*destroy)(struct meta_value *); 649 int (*compare)(struct meta_obj *, struct meta_obj *); 650 int (*change)(struct meta_value *, struct rtattr *); 651 void (*apply_extras)(struct meta_value *, struct meta_obj *); 652 int (*dump)(struct sk_buff *, struct meta_value *, int); 653 }; 654 655 static struct meta_type_ops __meta_type_ops[TCF_META_TYPE_MAX+1] = { 656 [TCF_META_TYPE_VAR] = { 657 .destroy = meta_var_destroy, 658 .compare = meta_var_compare, 659 .change = meta_var_change, 660 .apply_extras = meta_var_apply_extras, 661 .dump = meta_var_dump 662 }, 663 [TCF_META_TYPE_INT] = { 664 .compare = meta_int_compare, 665 .change = meta_int_change, 666 .apply_extras = meta_int_apply_extras, 667 .dump = meta_int_dump 668 } 669 }; 670 671 static inline struct meta_type_ops * meta_type_ops(struct meta_value *v) 672 { 673 return &__meta_type_ops[meta_type(v)]; 674 } 675 676 /************************************************************************** 677 * Core 678 **************************************************************************/ 679 680 static inline int meta_get(struct sk_buff *skb, struct tcf_pkt_info *info, 681 struct meta_value *v, struct meta_obj *dst) 682 { 683 int err = 0; 684 685 if (meta_id(v) == TCF_META_ID_VALUE) { 686 dst->value = v->val; 687 dst->len = v->len; 688 return 0; 689 } 690 691 meta_ops(v)->get(skb, info, v, dst, &err); 692 if (err < 0) 693 return err; 694 695 if (meta_type_ops(v)->apply_extras) 696 meta_type_ops(v)->apply_extras(v, dst); 697 698 return 0; 699 } 700 701 static int em_meta_match(struct sk_buff *skb, struct tcf_ematch *m, 702 struct tcf_pkt_info *info) 703 { 704 int r; 705 struct meta_match *meta = (struct meta_match *) m->data; 706 struct meta_obj l_value, r_value; 707 708 if (meta_get(skb, info, &meta->lvalue, &l_value) < 0 || 709 meta_get(skb, info, &meta->rvalue, &r_value) < 0) 710 return 0; 711 712 r = meta_type_ops(&meta->lvalue)->compare(&l_value, &r_value); 713 714 switch (meta->lvalue.hdr.op) { 715 case TCF_EM_OPND_EQ: 716 return !r; 717 case TCF_EM_OPND_LT: 718 return r < 0; 719 case TCF_EM_OPND_GT: 720 return r > 0; 721 } 722 723 return 0; 724 } 725 726 static inline void meta_delete(struct meta_match *meta) 727 { 728 struct meta_type_ops *ops = meta_type_ops(&meta->lvalue); 729 730 if (ops && ops->destroy) { 731 ops->destroy(&meta->lvalue); 732 ops->destroy(&meta->rvalue); 733 } 734 735 kfree(meta); 736 } 737 738 static inline int meta_change_data(struct meta_value *dst, struct rtattr *rta) 739 { 740 if (rta) { 741 if (RTA_PAYLOAD(rta) == 0) 742 return -EINVAL; 743 744 return meta_type_ops(dst)->change(dst, rta); 745 } 746 747 return 0; 748 } 749 750 static inline int meta_is_supported(struct meta_value *val) 751 { 752 return (!meta_id(val) || meta_ops(val)->get); 753 } 754 755 static int em_meta_change(struct tcf_proto *tp, void *data, int len, 756 struct tcf_ematch *m) 757 { 758 int err = -EINVAL; 759 struct rtattr *tb[TCA_EM_META_MAX]; 760 struct tcf_meta_hdr *hdr; 761 struct meta_match *meta = NULL; 762 763 if (rtattr_parse(tb, TCA_EM_META_MAX, data, len) < 0) 764 goto errout; 765 766 if (tb[TCA_EM_META_HDR-1] == NULL || 767 RTA_PAYLOAD(tb[TCA_EM_META_HDR-1]) < sizeof(*hdr)) 768 goto errout; 769 hdr = RTA_DATA(tb[TCA_EM_META_HDR-1]); 770 771 if (TCF_META_TYPE(hdr->left.kind) != TCF_META_TYPE(hdr->right.kind) || 772 TCF_META_TYPE(hdr->left.kind) > TCF_META_TYPE_MAX || 773 TCF_META_ID(hdr->left.kind) > TCF_META_ID_MAX || 774 TCF_META_ID(hdr->right.kind) > TCF_META_ID_MAX) 775 goto errout; 776 777 meta = kmalloc(sizeof(*meta), GFP_KERNEL); 778 if (meta == NULL) 779 goto errout; 780 memset(meta, 0, sizeof(*meta)); 781 782 memcpy(&meta->lvalue.hdr, &hdr->left, sizeof(hdr->left)); 783 memcpy(&meta->rvalue.hdr, &hdr->right, sizeof(hdr->right)); 784 785 if (!meta_is_supported(&meta->lvalue) || 786 !meta_is_supported(&meta->rvalue)) { 787 err = -EOPNOTSUPP; 788 goto errout; 789 } 790 791 if (meta_change_data(&meta->lvalue, tb[TCA_EM_META_LVALUE-1]) < 0 || 792 meta_change_data(&meta->rvalue, tb[TCA_EM_META_RVALUE-1]) < 0) 793 goto errout; 794 795 m->datalen = sizeof(*meta); 796 m->data = (unsigned long) meta; 797 798 err = 0; 799 errout: 800 if (err && meta) 801 meta_delete(meta); 802 return err; 803 } 804 805 static void em_meta_destroy(struct tcf_proto *tp, struct tcf_ematch *m) 806 { 807 if (m) 808 meta_delete((struct meta_match *) m->data); 809 } 810 811 static int em_meta_dump(struct sk_buff *skb, struct tcf_ematch *em) 812 { 813 struct meta_match *meta = (struct meta_match *) em->data; 814 struct tcf_meta_hdr hdr; 815 struct meta_type_ops *ops; 816 817 memset(&hdr, 0, sizeof(hdr)); 818 memcpy(&hdr.left, &meta->lvalue.hdr, sizeof(hdr.left)); 819 memcpy(&hdr.right, &meta->rvalue.hdr, sizeof(hdr.right)); 820 821 RTA_PUT(skb, TCA_EM_META_HDR, sizeof(hdr), &hdr); 822 823 ops = meta_type_ops(&meta->lvalue); 824 if (ops->dump(skb, &meta->lvalue, TCA_EM_META_LVALUE) < 0 || 825 ops->dump(skb, &meta->rvalue, TCA_EM_META_RVALUE) < 0) 826 goto rtattr_failure; 827 828 return 0; 829 830 rtattr_failure: 831 return -1; 832 } 833 834 static struct tcf_ematch_ops em_meta_ops = { 835 .kind = TCF_EM_META, 836 .change = em_meta_change, 837 .match = em_meta_match, 838 .destroy = em_meta_destroy, 839 .dump = em_meta_dump, 840 .owner = THIS_MODULE, 841 .link = LIST_HEAD_INIT(em_meta_ops.link) 842 }; 843 844 static int __init init_em_meta(void) 845 { 846 return tcf_em_register(&em_meta_ops); 847 } 848 849 static void __exit exit_em_meta(void) 850 { 851 tcf_em_unregister(&em_meta_ops); 852 } 853 854 MODULE_LICENSE("GPL"); 855 856 module_init(init_em_meta); 857 module_exit(exit_em_meta); 858