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/module.h> 62 #include <linux/types.h> 63 #include <linux/kernel.h> 64 #include <linux/sched.h> 65 #include <linux/string.h> 66 #include <linux/skbuff.h> 67 #include <linux/random.h> 68 #include <linux/tc_ematch/tc_em_meta.h> 69 #include <net/dst.h> 70 #include <net/route.h> 71 #include <net/pkt_cls.h> 72 #include <net/sock.h> 73 74 struct meta_obj 75 { 76 unsigned long value; 77 unsigned int len; 78 }; 79 80 struct meta_value 81 { 82 struct tcf_meta_val hdr; 83 unsigned long val; 84 unsigned int len; 85 }; 86 87 struct meta_match 88 { 89 struct meta_value lvalue; 90 struct meta_value rvalue; 91 }; 92 93 static inline int meta_id(struct meta_value *v) 94 { 95 return TCF_META_ID(v->hdr.kind); 96 } 97 98 static inline int meta_type(struct meta_value *v) 99 { 100 return TCF_META_TYPE(v->hdr.kind); 101 } 102 103 #define META_COLLECTOR(FUNC) static void meta_##FUNC(struct sk_buff *skb, \ 104 struct tcf_pkt_info *info, struct meta_value *v, \ 105 struct meta_obj *dst, int *err) 106 107 /************************************************************************** 108 * System status & misc 109 **************************************************************************/ 110 111 META_COLLECTOR(int_random) 112 { 113 get_random_bytes(&dst->value, sizeof(dst->value)); 114 } 115 116 static inline unsigned long fixed_loadavg(int load) 117 { 118 int rnd_load = load + (FIXED_1/200); 119 int rnd_frac = ((rnd_load & (FIXED_1-1)) * 100) >> FSHIFT; 120 121 return ((rnd_load >> FSHIFT) * 100) + rnd_frac; 122 } 123 124 META_COLLECTOR(int_loadavg_0) 125 { 126 dst->value = fixed_loadavg(avenrun[0]); 127 } 128 129 META_COLLECTOR(int_loadavg_1) 130 { 131 dst->value = fixed_loadavg(avenrun[1]); 132 } 133 134 META_COLLECTOR(int_loadavg_2) 135 { 136 dst->value = fixed_loadavg(avenrun[2]); 137 } 138 139 /************************************************************************** 140 * Device names & indices 141 **************************************************************************/ 142 143 static inline int int_dev(struct net_device *dev, struct meta_obj *dst) 144 { 145 if (unlikely(dev == NULL)) 146 return -1; 147 148 dst->value = dev->ifindex; 149 return 0; 150 } 151 152 static inline int var_dev(struct net_device *dev, struct meta_obj *dst) 153 { 154 if (unlikely(dev == NULL)) 155 return -1; 156 157 dst->value = (unsigned long) dev->name; 158 dst->len = strlen(dev->name); 159 return 0; 160 } 161 162 META_COLLECTOR(int_dev) 163 { 164 *err = int_dev(skb->dev, dst); 165 } 166 167 META_COLLECTOR(var_dev) 168 { 169 *err = var_dev(skb->dev, dst); 170 } 171 172 /************************************************************************** 173 * skb attributes 174 **************************************************************************/ 175 176 META_COLLECTOR(int_priority) 177 { 178 dst->value = skb->priority; 179 } 180 181 META_COLLECTOR(int_protocol) 182 { 183 /* Let userspace take care of the byte ordering */ 184 dst->value = skb->protocol; 185 } 186 187 META_COLLECTOR(int_pkttype) 188 { 189 dst->value = skb->pkt_type; 190 } 191 192 META_COLLECTOR(int_pktlen) 193 { 194 dst->value = skb->len; 195 } 196 197 META_COLLECTOR(int_datalen) 198 { 199 dst->value = skb->data_len; 200 } 201 202 META_COLLECTOR(int_maclen) 203 { 204 dst->value = skb->mac_len; 205 } 206 207 /************************************************************************** 208 * Netfilter 209 **************************************************************************/ 210 211 META_COLLECTOR(int_nfmark) 212 { 213 #ifdef CONFIG_NETFILTER 214 dst->value = skb->nfmark; 215 #else 216 dst->value = 0; 217 #endif 218 } 219 220 /************************************************************************** 221 * Traffic Control 222 **************************************************************************/ 223 224 META_COLLECTOR(int_tcindex) 225 { 226 dst->value = skb->tc_index; 227 } 228 229 /************************************************************************** 230 * Routing 231 **************************************************************************/ 232 233 META_COLLECTOR(int_rtclassid) 234 { 235 if (unlikely(skb->dst == NULL)) 236 *err = -1; 237 else 238 #ifdef CONFIG_NET_CLS_ROUTE 239 dst->value = skb->dst->tclassid; 240 #else 241 dst->value = 0; 242 #endif 243 } 244 245 META_COLLECTOR(int_rtiif) 246 { 247 if (unlikely(skb->dst == NULL)) 248 *err = -1; 249 else 250 dst->value = ((struct rtable*) skb->dst)->fl.iif; 251 } 252 253 /************************************************************************** 254 * Socket Attributes 255 **************************************************************************/ 256 257 #define SKIP_NONLOCAL(skb) \ 258 if (unlikely(skb->sk == NULL)) { \ 259 *err = -1; \ 260 return; \ 261 } 262 263 META_COLLECTOR(int_sk_family) 264 { 265 SKIP_NONLOCAL(skb); 266 dst->value = skb->sk->sk_family; 267 } 268 269 META_COLLECTOR(int_sk_state) 270 { 271 SKIP_NONLOCAL(skb); 272 dst->value = skb->sk->sk_state; 273 } 274 275 META_COLLECTOR(int_sk_reuse) 276 { 277 SKIP_NONLOCAL(skb); 278 dst->value = skb->sk->sk_reuse; 279 } 280 281 META_COLLECTOR(int_sk_bound_if) 282 { 283 SKIP_NONLOCAL(skb); 284 /* No error if bound_dev_if is 0, legal userspace check */ 285 dst->value = skb->sk->sk_bound_dev_if; 286 } 287 288 META_COLLECTOR(var_sk_bound_if) 289 { 290 SKIP_NONLOCAL(skb); 291 292 if (skb->sk->sk_bound_dev_if == 0) { 293 dst->value = (unsigned long) "any"; 294 dst->len = 3; 295 } else { 296 struct net_device *dev; 297 298 dev = dev_get_by_index(skb->sk->sk_bound_dev_if); 299 *err = var_dev(dev, dst); 300 if (dev) 301 dev_put(dev); 302 } 303 } 304 305 META_COLLECTOR(int_sk_refcnt) 306 { 307 SKIP_NONLOCAL(skb); 308 dst->value = atomic_read(&skb->sk->sk_refcnt); 309 } 310 311 META_COLLECTOR(int_sk_rcvbuf) 312 { 313 SKIP_NONLOCAL(skb); 314 dst->value = skb->sk->sk_rcvbuf; 315 } 316 317 META_COLLECTOR(int_sk_shutdown) 318 { 319 SKIP_NONLOCAL(skb); 320 dst->value = skb->sk->sk_shutdown; 321 } 322 323 META_COLLECTOR(int_sk_proto) 324 { 325 SKIP_NONLOCAL(skb); 326 dst->value = skb->sk->sk_protocol; 327 } 328 329 META_COLLECTOR(int_sk_type) 330 { 331 SKIP_NONLOCAL(skb); 332 dst->value = skb->sk->sk_type; 333 } 334 335 META_COLLECTOR(int_sk_rmem_alloc) 336 { 337 SKIP_NONLOCAL(skb); 338 dst->value = atomic_read(&skb->sk->sk_rmem_alloc); 339 } 340 341 META_COLLECTOR(int_sk_wmem_alloc) 342 { 343 SKIP_NONLOCAL(skb); 344 dst->value = atomic_read(&skb->sk->sk_wmem_alloc); 345 } 346 347 META_COLLECTOR(int_sk_omem_alloc) 348 { 349 SKIP_NONLOCAL(skb); 350 dst->value = atomic_read(&skb->sk->sk_omem_alloc); 351 } 352 353 META_COLLECTOR(int_sk_rcv_qlen) 354 { 355 SKIP_NONLOCAL(skb); 356 dst->value = skb->sk->sk_receive_queue.qlen; 357 } 358 359 META_COLLECTOR(int_sk_snd_qlen) 360 { 361 SKIP_NONLOCAL(skb); 362 dst->value = skb->sk->sk_write_queue.qlen; 363 } 364 365 META_COLLECTOR(int_sk_wmem_queued) 366 { 367 SKIP_NONLOCAL(skb); 368 dst->value = skb->sk->sk_wmem_queued; 369 } 370 371 META_COLLECTOR(int_sk_fwd_alloc) 372 { 373 SKIP_NONLOCAL(skb); 374 dst->value = skb->sk->sk_forward_alloc; 375 } 376 377 META_COLLECTOR(int_sk_sndbuf) 378 { 379 SKIP_NONLOCAL(skb); 380 dst->value = skb->sk->sk_sndbuf; 381 } 382 383 META_COLLECTOR(int_sk_alloc) 384 { 385 SKIP_NONLOCAL(skb); 386 dst->value = skb->sk->sk_allocation; 387 } 388 389 META_COLLECTOR(int_sk_route_caps) 390 { 391 SKIP_NONLOCAL(skb); 392 dst->value = skb->sk->sk_route_caps; 393 } 394 395 META_COLLECTOR(int_sk_hash) 396 { 397 SKIP_NONLOCAL(skb); 398 dst->value = skb->sk->sk_hash; 399 } 400 401 META_COLLECTOR(int_sk_lingertime) 402 { 403 SKIP_NONLOCAL(skb); 404 dst->value = skb->sk->sk_lingertime / HZ; 405 } 406 407 META_COLLECTOR(int_sk_err_qlen) 408 { 409 SKIP_NONLOCAL(skb); 410 dst->value = skb->sk->sk_error_queue.qlen; 411 } 412 413 META_COLLECTOR(int_sk_ack_bl) 414 { 415 SKIP_NONLOCAL(skb); 416 dst->value = skb->sk->sk_ack_backlog; 417 } 418 419 META_COLLECTOR(int_sk_max_ack_bl) 420 { 421 SKIP_NONLOCAL(skb); 422 dst->value = skb->sk->sk_max_ack_backlog; 423 } 424 425 META_COLLECTOR(int_sk_prio) 426 { 427 SKIP_NONLOCAL(skb); 428 dst->value = skb->sk->sk_priority; 429 } 430 431 META_COLLECTOR(int_sk_rcvlowat) 432 { 433 SKIP_NONLOCAL(skb); 434 dst->value = skb->sk->sk_rcvlowat; 435 } 436 437 META_COLLECTOR(int_sk_rcvtimeo) 438 { 439 SKIP_NONLOCAL(skb); 440 dst->value = skb->sk->sk_rcvtimeo / HZ; 441 } 442 443 META_COLLECTOR(int_sk_sndtimeo) 444 { 445 SKIP_NONLOCAL(skb); 446 dst->value = skb->sk->sk_sndtimeo / HZ; 447 } 448 449 META_COLLECTOR(int_sk_sendmsg_off) 450 { 451 SKIP_NONLOCAL(skb); 452 dst->value = skb->sk->sk_sndmsg_off; 453 } 454 455 META_COLLECTOR(int_sk_write_pend) 456 { 457 SKIP_NONLOCAL(skb); 458 dst->value = skb->sk->sk_write_pending; 459 } 460 461 /************************************************************************** 462 * Meta value collectors assignment table 463 **************************************************************************/ 464 465 struct meta_ops 466 { 467 void (*get)(struct sk_buff *, struct tcf_pkt_info *, 468 struct meta_value *, struct meta_obj *, int *); 469 }; 470 471 #define META_ID(name) TCF_META_ID_##name 472 #define META_FUNC(name) { .get = meta_##name } 473 474 /* Meta value operations table listing all meta value collectors and 475 * assigns them to a type and meta id. */ 476 static struct meta_ops __meta_ops[TCF_META_TYPE_MAX+1][TCF_META_ID_MAX+1] = { 477 [TCF_META_TYPE_VAR] = { 478 [META_ID(DEV)] = META_FUNC(var_dev), 479 [META_ID(SK_BOUND_IF)] = META_FUNC(var_sk_bound_if), 480 }, 481 [TCF_META_TYPE_INT] = { 482 [META_ID(RANDOM)] = META_FUNC(int_random), 483 [META_ID(LOADAVG_0)] = META_FUNC(int_loadavg_0), 484 [META_ID(LOADAVG_1)] = META_FUNC(int_loadavg_1), 485 [META_ID(LOADAVG_2)] = META_FUNC(int_loadavg_2), 486 [META_ID(DEV)] = META_FUNC(int_dev), 487 [META_ID(PRIORITY)] = META_FUNC(int_priority), 488 [META_ID(PROTOCOL)] = META_FUNC(int_protocol), 489 [META_ID(PKTTYPE)] = META_FUNC(int_pkttype), 490 [META_ID(PKTLEN)] = META_FUNC(int_pktlen), 491 [META_ID(DATALEN)] = META_FUNC(int_datalen), 492 [META_ID(MACLEN)] = META_FUNC(int_maclen), 493 [META_ID(NFMARK)] = META_FUNC(int_nfmark), 494 [META_ID(TCINDEX)] = META_FUNC(int_tcindex), 495 [META_ID(RTCLASSID)] = META_FUNC(int_rtclassid), 496 [META_ID(RTIIF)] = META_FUNC(int_rtiif), 497 [META_ID(SK_FAMILY)] = META_FUNC(int_sk_family), 498 [META_ID(SK_STATE)] = META_FUNC(int_sk_state), 499 [META_ID(SK_REUSE)] = META_FUNC(int_sk_reuse), 500 [META_ID(SK_BOUND_IF)] = META_FUNC(int_sk_bound_if), 501 [META_ID(SK_REFCNT)] = META_FUNC(int_sk_refcnt), 502 [META_ID(SK_RCVBUF)] = META_FUNC(int_sk_rcvbuf), 503 [META_ID(SK_SNDBUF)] = META_FUNC(int_sk_sndbuf), 504 [META_ID(SK_SHUTDOWN)] = META_FUNC(int_sk_shutdown), 505 [META_ID(SK_PROTO)] = META_FUNC(int_sk_proto), 506 [META_ID(SK_TYPE)] = META_FUNC(int_sk_type), 507 [META_ID(SK_RMEM_ALLOC)] = META_FUNC(int_sk_rmem_alloc), 508 [META_ID(SK_WMEM_ALLOC)] = META_FUNC(int_sk_wmem_alloc), 509 [META_ID(SK_OMEM_ALLOC)] = META_FUNC(int_sk_omem_alloc), 510 [META_ID(SK_WMEM_QUEUED)] = META_FUNC(int_sk_wmem_queued), 511 [META_ID(SK_RCV_QLEN)] = META_FUNC(int_sk_rcv_qlen), 512 [META_ID(SK_SND_QLEN)] = META_FUNC(int_sk_snd_qlen), 513 [META_ID(SK_ERR_QLEN)] = META_FUNC(int_sk_err_qlen), 514 [META_ID(SK_FORWARD_ALLOCS)] = META_FUNC(int_sk_fwd_alloc), 515 [META_ID(SK_ALLOCS)] = META_FUNC(int_sk_alloc), 516 [META_ID(SK_ROUTE_CAPS)] = META_FUNC(int_sk_route_caps), 517 [META_ID(SK_HASH)] = META_FUNC(int_sk_hash), 518 [META_ID(SK_LINGERTIME)] = META_FUNC(int_sk_lingertime), 519 [META_ID(SK_ACK_BACKLOG)] = META_FUNC(int_sk_ack_bl), 520 [META_ID(SK_MAX_ACK_BACKLOG)] = META_FUNC(int_sk_max_ack_bl), 521 [META_ID(SK_PRIO)] = META_FUNC(int_sk_prio), 522 [META_ID(SK_RCVLOWAT)] = META_FUNC(int_sk_rcvlowat), 523 [META_ID(SK_RCVTIMEO)] = META_FUNC(int_sk_rcvtimeo), 524 [META_ID(SK_SNDTIMEO)] = META_FUNC(int_sk_sndtimeo), 525 [META_ID(SK_SENDMSG_OFF)] = META_FUNC(int_sk_sendmsg_off), 526 [META_ID(SK_WRITE_PENDING)] = META_FUNC(int_sk_write_pend), 527 } 528 }; 529 530 static inline struct meta_ops * meta_ops(struct meta_value *val) 531 { 532 return &__meta_ops[meta_type(val)][meta_id(val)]; 533 } 534 535 /************************************************************************** 536 * Type specific operations for TCF_META_TYPE_VAR 537 **************************************************************************/ 538 539 static int meta_var_compare(struct meta_obj *a, struct meta_obj *b) 540 { 541 int r = a->len - b->len; 542 543 if (r == 0) 544 r = memcmp((void *) a->value, (void *) b->value, a->len); 545 546 return r; 547 } 548 549 static int meta_var_change(struct meta_value *dst, struct rtattr *rta) 550 { 551 int len = RTA_PAYLOAD(rta); 552 553 dst->val = (unsigned long) kmalloc(len, GFP_KERNEL); 554 if (dst->val == 0UL) 555 return -ENOMEM; 556 memcpy((void *) dst->val, RTA_DATA(rta), len); 557 dst->len = len; 558 return 0; 559 } 560 561 static void meta_var_destroy(struct meta_value *v) 562 { 563 kfree((void *) v->val); 564 } 565 566 static void meta_var_apply_extras(struct meta_value *v, 567 struct meta_obj *dst) 568 { 569 int shift = v->hdr.shift; 570 571 if (shift && shift < dst->len) 572 dst->len -= shift; 573 } 574 575 static int meta_var_dump(struct sk_buff *skb, struct meta_value *v, int tlv) 576 { 577 if (v->val && v->len) 578 RTA_PUT(skb, tlv, v->len, (void *) v->val); 579 return 0; 580 581 rtattr_failure: 582 return -1; 583 } 584 585 /************************************************************************** 586 * Type specific operations for TCF_META_TYPE_INT 587 **************************************************************************/ 588 589 static int meta_int_compare(struct meta_obj *a, struct meta_obj *b) 590 { 591 /* Let gcc optimize it, the unlikely is not really based on 592 * some numbers but jump free code for mismatches seems 593 * more logical. */ 594 if (unlikely(a->value == b->value)) 595 return 0; 596 else if (a->value < b->value) 597 return -1; 598 else 599 return 1; 600 } 601 602 static int meta_int_change(struct meta_value *dst, struct rtattr *rta) 603 { 604 if (RTA_PAYLOAD(rta) >= sizeof(unsigned long)) { 605 dst->val = *(unsigned long *) RTA_DATA(rta); 606 dst->len = sizeof(unsigned long); 607 } else if (RTA_PAYLOAD(rta) == sizeof(u32)) { 608 dst->val = *(u32 *) RTA_DATA(rta); 609 dst->len = sizeof(u32); 610 } else 611 return -EINVAL; 612 613 return 0; 614 } 615 616 static void meta_int_apply_extras(struct meta_value *v, 617 struct meta_obj *dst) 618 { 619 if (v->hdr.shift) 620 dst->value >>= v->hdr.shift; 621 622 if (v->val) 623 dst->value &= v->val; 624 } 625 626 static int meta_int_dump(struct sk_buff *skb, struct meta_value *v, int tlv) 627 { 628 if (v->len == sizeof(unsigned long)) 629 RTA_PUT(skb, tlv, sizeof(unsigned long), &v->val); 630 else if (v->len == sizeof(u32)) { 631 u32 d = v->val; 632 RTA_PUT(skb, tlv, sizeof(d), &d); 633 } 634 635 return 0; 636 637 rtattr_failure: 638 return -1; 639 } 640 641 /************************************************************************** 642 * Type specific operations table 643 **************************************************************************/ 644 645 struct meta_type_ops 646 { 647 void (*destroy)(struct meta_value *); 648 int (*compare)(struct meta_obj *, struct meta_obj *); 649 int (*change)(struct meta_value *, struct rtattr *); 650 void (*apply_extras)(struct meta_value *, struct meta_obj *); 651 int (*dump)(struct sk_buff *, struct meta_value *, int); 652 }; 653 654 static struct meta_type_ops __meta_type_ops[TCF_META_TYPE_MAX+1] = { 655 [TCF_META_TYPE_VAR] = { 656 .destroy = meta_var_destroy, 657 .compare = meta_var_compare, 658 .change = meta_var_change, 659 .apply_extras = meta_var_apply_extras, 660 .dump = meta_var_dump 661 }, 662 [TCF_META_TYPE_INT] = { 663 .compare = meta_int_compare, 664 .change = meta_int_change, 665 .apply_extras = meta_int_apply_extras, 666 .dump = meta_int_dump 667 } 668 }; 669 670 static inline struct meta_type_ops * meta_type_ops(struct meta_value *v) 671 { 672 return &__meta_type_ops[meta_type(v)]; 673 } 674 675 /************************************************************************** 676 * Core 677 **************************************************************************/ 678 679 static inline int meta_get(struct sk_buff *skb, struct tcf_pkt_info *info, 680 struct meta_value *v, struct meta_obj *dst) 681 { 682 int err = 0; 683 684 if (meta_id(v) == TCF_META_ID_VALUE) { 685 dst->value = v->val; 686 dst->len = v->len; 687 return 0; 688 } 689 690 meta_ops(v)->get(skb, info, v, dst, &err); 691 if (err < 0) 692 return err; 693 694 if (meta_type_ops(v)->apply_extras) 695 meta_type_ops(v)->apply_extras(v, dst); 696 697 return 0; 698 } 699 700 static int em_meta_match(struct sk_buff *skb, struct tcf_ematch *m, 701 struct tcf_pkt_info *info) 702 { 703 int r; 704 struct meta_match *meta = (struct meta_match *) m->data; 705 struct meta_obj l_value, r_value; 706 707 if (meta_get(skb, info, &meta->lvalue, &l_value) < 0 || 708 meta_get(skb, info, &meta->rvalue, &r_value) < 0) 709 return 0; 710 711 r = meta_type_ops(&meta->lvalue)->compare(&l_value, &r_value); 712 713 switch (meta->lvalue.hdr.op) { 714 case TCF_EM_OPND_EQ: 715 return !r; 716 case TCF_EM_OPND_LT: 717 return r < 0; 718 case TCF_EM_OPND_GT: 719 return r > 0; 720 } 721 722 return 0; 723 } 724 725 static inline void meta_delete(struct meta_match *meta) 726 { 727 struct meta_type_ops *ops = meta_type_ops(&meta->lvalue); 728 729 if (ops && ops->destroy) { 730 ops->destroy(&meta->lvalue); 731 ops->destroy(&meta->rvalue); 732 } 733 734 kfree(meta); 735 } 736 737 static inline int meta_change_data(struct meta_value *dst, struct rtattr *rta) 738 { 739 if (rta) { 740 if (RTA_PAYLOAD(rta) == 0) 741 return -EINVAL; 742 743 return meta_type_ops(dst)->change(dst, rta); 744 } 745 746 return 0; 747 } 748 749 static inline int meta_is_supported(struct meta_value *val) 750 { 751 return (!meta_id(val) || meta_ops(val)->get); 752 } 753 754 static int em_meta_change(struct tcf_proto *tp, void *data, int len, 755 struct tcf_ematch *m) 756 { 757 int err = -EINVAL; 758 struct rtattr *tb[TCA_EM_META_MAX]; 759 struct tcf_meta_hdr *hdr; 760 struct meta_match *meta = NULL; 761 762 if (rtattr_parse(tb, TCA_EM_META_MAX, data, len) < 0) 763 goto errout; 764 765 if (tb[TCA_EM_META_HDR-1] == NULL || 766 RTA_PAYLOAD(tb[TCA_EM_META_HDR-1]) < sizeof(*hdr)) 767 goto errout; 768 hdr = RTA_DATA(tb[TCA_EM_META_HDR-1]); 769 770 if (TCF_META_TYPE(hdr->left.kind) != TCF_META_TYPE(hdr->right.kind) || 771 TCF_META_TYPE(hdr->left.kind) > TCF_META_TYPE_MAX || 772 TCF_META_ID(hdr->left.kind) > TCF_META_ID_MAX || 773 TCF_META_ID(hdr->right.kind) > TCF_META_ID_MAX) 774 goto errout; 775 776 meta = kzalloc(sizeof(*meta), GFP_KERNEL); 777 if (meta == NULL) 778 goto errout; 779 780 memcpy(&meta->lvalue.hdr, &hdr->left, sizeof(hdr->left)); 781 memcpy(&meta->rvalue.hdr, &hdr->right, sizeof(hdr->right)); 782 783 if (!meta_is_supported(&meta->lvalue) || 784 !meta_is_supported(&meta->rvalue)) { 785 err = -EOPNOTSUPP; 786 goto errout; 787 } 788 789 if (meta_change_data(&meta->lvalue, tb[TCA_EM_META_LVALUE-1]) < 0 || 790 meta_change_data(&meta->rvalue, tb[TCA_EM_META_RVALUE-1]) < 0) 791 goto errout; 792 793 m->datalen = sizeof(*meta); 794 m->data = (unsigned long) meta; 795 796 err = 0; 797 errout: 798 if (err && meta) 799 meta_delete(meta); 800 return err; 801 } 802 803 static void em_meta_destroy(struct tcf_proto *tp, struct tcf_ematch *m) 804 { 805 if (m) 806 meta_delete((struct meta_match *) m->data); 807 } 808 809 static int em_meta_dump(struct sk_buff *skb, struct tcf_ematch *em) 810 { 811 struct meta_match *meta = (struct meta_match *) em->data; 812 struct tcf_meta_hdr hdr; 813 struct meta_type_ops *ops; 814 815 memset(&hdr, 0, sizeof(hdr)); 816 memcpy(&hdr.left, &meta->lvalue.hdr, sizeof(hdr.left)); 817 memcpy(&hdr.right, &meta->rvalue.hdr, sizeof(hdr.right)); 818 819 RTA_PUT(skb, TCA_EM_META_HDR, sizeof(hdr), &hdr); 820 821 ops = meta_type_ops(&meta->lvalue); 822 if (ops->dump(skb, &meta->lvalue, TCA_EM_META_LVALUE) < 0 || 823 ops->dump(skb, &meta->rvalue, TCA_EM_META_RVALUE) < 0) 824 goto rtattr_failure; 825 826 return 0; 827 828 rtattr_failure: 829 return -1; 830 } 831 832 static struct tcf_ematch_ops em_meta_ops = { 833 .kind = TCF_EM_META, 834 .change = em_meta_change, 835 .match = em_meta_match, 836 .destroy = em_meta_destroy, 837 .dump = em_meta_dump, 838 .owner = THIS_MODULE, 839 .link = LIST_HEAD_INIT(em_meta_ops.link) 840 }; 841 842 static int __init init_em_meta(void) 843 { 844 return tcf_em_register(&em_meta_ops); 845 } 846 847 static void __exit exit_em_meta(void) 848 { 849 tcf_em_unregister(&em_meta_ops); 850 } 851 852 MODULE_LICENSE("GPL"); 853 854 module_init(init_em_meta); 855 module_exit(exit_em_meta); 856