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: INDEV | | id: VALUE | 31 * | data: | | data: 3 | 32 * +-----------+ +-----------+ 33 * | | 34 * ---> meta_ops[INT][INDEV](...) | 35 * | | 36 * ----------- | 37 * V V 38 * +-----------+ +-----------+ 39 * | type: INT | | type: INT | 40 * obj | id: INDEV | | 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 META_COLLECTOR(int_indev) 174 { 175 *err = int_dev(skb->input_dev, dst); 176 } 177 178 META_COLLECTOR(var_indev) 179 { 180 *err = var_dev(skb->input_dev, dst); 181 } 182 183 META_COLLECTOR(int_realdev) 184 { 185 *err = int_dev(skb->real_dev, dst); 186 } 187 188 META_COLLECTOR(var_realdev) 189 { 190 *err = var_dev(skb->real_dev, dst); 191 } 192 193 /************************************************************************** 194 * skb attributes 195 **************************************************************************/ 196 197 META_COLLECTOR(int_priority) 198 { 199 dst->value = skb->priority; 200 } 201 202 META_COLLECTOR(int_protocol) 203 { 204 /* Let userspace take care of the byte ordering */ 205 dst->value = skb->protocol; 206 } 207 208 META_COLLECTOR(int_security) 209 { 210 dst->value = skb->security; 211 } 212 213 META_COLLECTOR(int_pkttype) 214 { 215 dst->value = skb->pkt_type; 216 } 217 218 META_COLLECTOR(int_pktlen) 219 { 220 dst->value = skb->len; 221 } 222 223 META_COLLECTOR(int_datalen) 224 { 225 dst->value = skb->data_len; 226 } 227 228 META_COLLECTOR(int_maclen) 229 { 230 dst->value = skb->mac_len; 231 } 232 233 /************************************************************************** 234 * Netfilter 235 **************************************************************************/ 236 237 #ifdef CONFIG_NETFILTER 238 META_COLLECTOR(int_nfmark) 239 { 240 dst->value = skb->nfmark; 241 } 242 #endif 243 244 /************************************************************************** 245 * Traffic Control 246 **************************************************************************/ 247 248 META_COLLECTOR(int_tcindex) 249 { 250 dst->value = skb->tc_index; 251 } 252 253 #ifdef CONFIG_NET_CLS_ACT 254 META_COLLECTOR(int_tcverd) 255 { 256 dst->value = skb->tc_verd; 257 } 258 259 META_COLLECTOR(int_tcclassid) 260 { 261 dst->value = skb->tc_classid; 262 } 263 #endif 264 265 /************************************************************************** 266 * Routing 267 **************************************************************************/ 268 269 #ifdef CONFIG_NET_CLS_ROUTE 270 META_COLLECTOR(int_rtclassid) 271 { 272 if (unlikely(skb->dst == NULL)) 273 *err = -1; 274 else 275 dst->value = skb->dst->tclassid; 276 } 277 #endif 278 279 META_COLLECTOR(int_rtiif) 280 { 281 if (unlikely(skb->dst == NULL)) 282 *err = -1; 283 else 284 dst->value = ((struct rtable*) skb->dst)->fl.iif; 285 } 286 287 /************************************************************************** 288 * Socket Attributes 289 **************************************************************************/ 290 291 #define SKIP_NONLOCAL(skb) \ 292 if (unlikely(skb->sk == NULL)) { \ 293 *err = -1; \ 294 return; \ 295 } 296 297 META_COLLECTOR(int_sk_family) 298 { 299 SKIP_NONLOCAL(skb); 300 dst->value = skb->sk->sk_family; 301 } 302 303 META_COLLECTOR(int_sk_state) 304 { 305 SKIP_NONLOCAL(skb); 306 dst->value = skb->sk->sk_state; 307 } 308 309 META_COLLECTOR(int_sk_reuse) 310 { 311 SKIP_NONLOCAL(skb); 312 dst->value = skb->sk->sk_reuse; 313 } 314 315 META_COLLECTOR(int_sk_bound_if) 316 { 317 SKIP_NONLOCAL(skb); 318 /* No error if bound_dev_if is 0, legal userspace check */ 319 dst->value = skb->sk->sk_bound_dev_if; 320 } 321 322 META_COLLECTOR(var_sk_bound_if) 323 { 324 SKIP_NONLOCAL(skb); 325 326 if (skb->sk->sk_bound_dev_if == 0) { 327 dst->value = (unsigned long) "any"; 328 dst->len = 3; 329 } else { 330 struct net_device *dev; 331 332 dev = dev_get_by_index(skb->sk->sk_bound_dev_if); 333 *err = var_dev(dev, dst); 334 if (dev) 335 dev_put(dev); 336 } 337 } 338 339 META_COLLECTOR(int_sk_refcnt) 340 { 341 SKIP_NONLOCAL(skb); 342 dst->value = atomic_read(&skb->sk->sk_refcnt); 343 } 344 345 META_COLLECTOR(int_sk_rcvbuf) 346 { 347 SKIP_NONLOCAL(skb); 348 dst->value = skb->sk->sk_rcvbuf; 349 } 350 351 META_COLLECTOR(int_sk_shutdown) 352 { 353 SKIP_NONLOCAL(skb); 354 dst->value = skb->sk->sk_shutdown; 355 } 356 357 META_COLLECTOR(int_sk_proto) 358 { 359 SKIP_NONLOCAL(skb); 360 dst->value = skb->sk->sk_protocol; 361 } 362 363 META_COLLECTOR(int_sk_type) 364 { 365 SKIP_NONLOCAL(skb); 366 dst->value = skb->sk->sk_type; 367 } 368 369 META_COLLECTOR(int_sk_rmem_alloc) 370 { 371 SKIP_NONLOCAL(skb); 372 dst->value = atomic_read(&skb->sk->sk_rmem_alloc); 373 } 374 375 META_COLLECTOR(int_sk_wmem_alloc) 376 { 377 SKIP_NONLOCAL(skb); 378 dst->value = atomic_read(&skb->sk->sk_wmem_alloc); 379 } 380 381 META_COLLECTOR(int_sk_omem_alloc) 382 { 383 SKIP_NONLOCAL(skb); 384 dst->value = atomic_read(&skb->sk->sk_omem_alloc); 385 } 386 387 META_COLLECTOR(int_sk_rcv_qlen) 388 { 389 SKIP_NONLOCAL(skb); 390 dst->value = skb->sk->sk_receive_queue.qlen; 391 } 392 393 META_COLLECTOR(int_sk_snd_qlen) 394 { 395 SKIP_NONLOCAL(skb); 396 dst->value = skb->sk->sk_write_queue.qlen; 397 } 398 399 META_COLLECTOR(int_sk_wmem_queued) 400 { 401 SKIP_NONLOCAL(skb); 402 dst->value = skb->sk->sk_wmem_queued; 403 } 404 405 META_COLLECTOR(int_sk_fwd_alloc) 406 { 407 SKIP_NONLOCAL(skb); 408 dst->value = skb->sk->sk_forward_alloc; 409 } 410 411 META_COLLECTOR(int_sk_sndbuf) 412 { 413 SKIP_NONLOCAL(skb); 414 dst->value = skb->sk->sk_sndbuf; 415 } 416 417 META_COLLECTOR(int_sk_alloc) 418 { 419 SKIP_NONLOCAL(skb); 420 dst->value = skb->sk->sk_allocation; 421 } 422 423 META_COLLECTOR(int_sk_route_caps) 424 { 425 SKIP_NONLOCAL(skb); 426 dst->value = skb->sk->sk_route_caps; 427 } 428 429 META_COLLECTOR(int_sk_hashent) 430 { 431 SKIP_NONLOCAL(skb); 432 dst->value = skb->sk->sk_hashent; 433 } 434 435 META_COLLECTOR(int_sk_lingertime) 436 { 437 SKIP_NONLOCAL(skb); 438 dst->value = skb->sk->sk_lingertime / HZ; 439 } 440 441 META_COLLECTOR(int_sk_err_qlen) 442 { 443 SKIP_NONLOCAL(skb); 444 dst->value = skb->sk->sk_error_queue.qlen; 445 } 446 447 META_COLLECTOR(int_sk_ack_bl) 448 { 449 SKIP_NONLOCAL(skb); 450 dst->value = skb->sk->sk_ack_backlog; 451 } 452 453 META_COLLECTOR(int_sk_max_ack_bl) 454 { 455 SKIP_NONLOCAL(skb); 456 dst->value = skb->sk->sk_max_ack_backlog; 457 } 458 459 META_COLLECTOR(int_sk_prio) 460 { 461 SKIP_NONLOCAL(skb); 462 dst->value = skb->sk->sk_priority; 463 } 464 465 META_COLLECTOR(int_sk_rcvlowat) 466 { 467 SKIP_NONLOCAL(skb); 468 dst->value = skb->sk->sk_rcvlowat; 469 } 470 471 META_COLLECTOR(int_sk_rcvtimeo) 472 { 473 SKIP_NONLOCAL(skb); 474 dst->value = skb->sk->sk_rcvtimeo / HZ; 475 } 476 477 META_COLLECTOR(int_sk_sndtimeo) 478 { 479 SKIP_NONLOCAL(skb); 480 dst->value = skb->sk->sk_sndtimeo / HZ; 481 } 482 483 META_COLLECTOR(int_sk_sendmsg_off) 484 { 485 SKIP_NONLOCAL(skb); 486 dst->value = skb->sk->sk_sndmsg_off; 487 } 488 489 META_COLLECTOR(int_sk_write_pend) 490 { 491 SKIP_NONLOCAL(skb); 492 dst->value = skb->sk->sk_write_pending; 493 } 494 495 /************************************************************************** 496 * Meta value collectors assignment table 497 **************************************************************************/ 498 499 struct meta_ops 500 { 501 void (*get)(struct sk_buff *, struct tcf_pkt_info *, 502 struct meta_value *, struct meta_obj *, int *); 503 }; 504 505 #define META_ID(name) TCF_META_ID_##name 506 #define META_FUNC(name) { .get = meta_##name } 507 508 /* Meta value operations table listing all meta value collectors and 509 * assigns them to a type and meta id. */ 510 static struct meta_ops __meta_ops[TCF_META_TYPE_MAX+1][TCF_META_ID_MAX+1] = { 511 [TCF_META_TYPE_VAR] = { 512 [META_ID(DEV)] = META_FUNC(var_dev), 513 [META_ID(INDEV)] = META_FUNC(var_indev), 514 [META_ID(REALDEV)] = META_FUNC(var_realdev), 515 [META_ID(SK_BOUND_IF)] = META_FUNC(var_sk_bound_if), 516 }, 517 [TCF_META_TYPE_INT] = { 518 [META_ID(RANDOM)] = META_FUNC(int_random), 519 [META_ID(LOADAVG_0)] = META_FUNC(int_loadavg_0), 520 [META_ID(LOADAVG_1)] = META_FUNC(int_loadavg_1), 521 [META_ID(LOADAVG_2)] = META_FUNC(int_loadavg_2), 522 [META_ID(DEV)] = META_FUNC(int_dev), 523 [META_ID(INDEV)] = META_FUNC(int_indev), 524 [META_ID(REALDEV)] = META_FUNC(int_realdev), 525 [META_ID(PRIORITY)] = META_FUNC(int_priority), 526 [META_ID(PROTOCOL)] = META_FUNC(int_protocol), 527 [META_ID(SECURITY)] = META_FUNC(int_security), 528 [META_ID(PKTTYPE)] = META_FUNC(int_pkttype), 529 [META_ID(PKTLEN)] = META_FUNC(int_pktlen), 530 [META_ID(DATALEN)] = META_FUNC(int_datalen), 531 [META_ID(MACLEN)] = META_FUNC(int_maclen), 532 #ifdef CONFIG_NETFILTER 533 [META_ID(NFMARK)] = META_FUNC(int_nfmark), 534 #endif 535 [META_ID(TCINDEX)] = META_FUNC(int_tcindex), 536 #ifdef CONFIG_NET_CLS_ACT 537 [META_ID(TCVERDICT)] = META_FUNC(int_tcverd), 538 [META_ID(TCCLASSID)] = META_FUNC(int_tcclassid), 539 #endif 540 #ifdef CONFIG_NET_CLS_ROUTE 541 [META_ID(RTCLASSID)] = META_FUNC(int_rtclassid), 542 #endif 543 [META_ID(RTIIF)] = META_FUNC(int_rtiif), 544 [META_ID(SK_FAMILY)] = META_FUNC(int_sk_family), 545 [META_ID(SK_STATE)] = META_FUNC(int_sk_state), 546 [META_ID(SK_REUSE)] = META_FUNC(int_sk_reuse), 547 [META_ID(SK_BOUND_IF)] = META_FUNC(int_sk_bound_if), 548 [META_ID(SK_REFCNT)] = META_FUNC(int_sk_refcnt), 549 [META_ID(SK_RCVBUF)] = META_FUNC(int_sk_rcvbuf), 550 [META_ID(SK_SNDBUF)] = META_FUNC(int_sk_sndbuf), 551 [META_ID(SK_SHUTDOWN)] = META_FUNC(int_sk_shutdown), 552 [META_ID(SK_PROTO)] = META_FUNC(int_sk_proto), 553 [META_ID(SK_TYPE)] = META_FUNC(int_sk_type), 554 [META_ID(SK_RMEM_ALLOC)] = META_FUNC(int_sk_rmem_alloc), 555 [META_ID(SK_WMEM_ALLOC)] = META_FUNC(int_sk_wmem_alloc), 556 [META_ID(SK_OMEM_ALLOC)] = META_FUNC(int_sk_omem_alloc), 557 [META_ID(SK_WMEM_QUEUED)] = META_FUNC(int_sk_wmem_queued), 558 [META_ID(SK_RCV_QLEN)] = META_FUNC(int_sk_rcv_qlen), 559 [META_ID(SK_SND_QLEN)] = META_FUNC(int_sk_snd_qlen), 560 [META_ID(SK_ERR_QLEN)] = META_FUNC(int_sk_err_qlen), 561 [META_ID(SK_FORWARD_ALLOCS)] = META_FUNC(int_sk_fwd_alloc), 562 [META_ID(SK_ALLOCS)] = META_FUNC(int_sk_alloc), 563 [META_ID(SK_ROUTE_CAPS)] = META_FUNC(int_sk_route_caps), 564 [META_ID(SK_HASHENT)] = META_FUNC(int_sk_hashent), 565 [META_ID(SK_LINGERTIME)] = META_FUNC(int_sk_lingertime), 566 [META_ID(SK_ACK_BACKLOG)] = META_FUNC(int_sk_ack_bl), 567 [META_ID(SK_MAX_ACK_BACKLOG)] = META_FUNC(int_sk_max_ack_bl), 568 [META_ID(SK_PRIO)] = META_FUNC(int_sk_prio), 569 [META_ID(SK_RCVLOWAT)] = META_FUNC(int_sk_rcvlowat), 570 [META_ID(SK_RCVTIMEO)] = META_FUNC(int_sk_rcvtimeo), 571 [META_ID(SK_SNDTIMEO)] = META_FUNC(int_sk_sndtimeo), 572 [META_ID(SK_SENDMSG_OFF)] = META_FUNC(int_sk_sendmsg_off), 573 [META_ID(SK_WRITE_PENDING)] = META_FUNC(int_sk_write_pend), 574 } 575 }; 576 577 static inline struct meta_ops * meta_ops(struct meta_value *val) 578 { 579 return &__meta_ops[meta_type(val)][meta_id(val)]; 580 } 581 582 /************************************************************************** 583 * Type specific operations for TCF_META_TYPE_VAR 584 **************************************************************************/ 585 586 static int meta_var_compare(struct meta_obj *a, struct meta_obj *b) 587 { 588 int r = a->len - b->len; 589 590 if (r == 0) 591 r = memcmp((void *) a->value, (void *) b->value, a->len); 592 593 return r; 594 } 595 596 static int meta_var_change(struct meta_value *dst, struct rtattr *rta) 597 { 598 int len = RTA_PAYLOAD(rta); 599 600 dst->val = (unsigned long) kmalloc(len, GFP_KERNEL); 601 if (dst->val == 0UL) 602 return -ENOMEM; 603 memcpy((void *) dst->val, RTA_DATA(rta), len); 604 dst->len = len; 605 return 0; 606 } 607 608 static void meta_var_destroy(struct meta_value *v) 609 { 610 if (v->val) 611 kfree((void *) v->val); 612 } 613 614 static void meta_var_apply_extras(struct meta_value *v, 615 struct meta_obj *dst) 616 { 617 int shift = v->hdr.shift; 618 619 if (shift && shift < dst->len) 620 dst->len -= shift; 621 } 622 623 static int meta_var_dump(struct sk_buff *skb, struct meta_value *v, int tlv) 624 { 625 if (v->val && v->len) 626 RTA_PUT(skb, tlv, v->len, (void *) v->val); 627 return 0; 628 629 rtattr_failure: 630 return -1; 631 } 632 633 /************************************************************************** 634 * Type specific operations for TCF_META_TYPE_INT 635 **************************************************************************/ 636 637 static int meta_int_compare(struct meta_obj *a, struct meta_obj *b) 638 { 639 /* Let gcc optimize it, the unlikely is not really based on 640 * some numbers but jump free code for mismatches seems 641 * more logical. */ 642 if (unlikely(a->value == b->value)) 643 return 0; 644 else if (a->value < b->value) 645 return -1; 646 else 647 return 1; 648 } 649 650 static int meta_int_change(struct meta_value *dst, struct rtattr *rta) 651 { 652 if (RTA_PAYLOAD(rta) >= sizeof(unsigned long)) { 653 dst->val = *(unsigned long *) RTA_DATA(rta); 654 dst->len = sizeof(unsigned long); 655 } else if (RTA_PAYLOAD(rta) == sizeof(u32)) { 656 dst->val = *(u32 *) RTA_DATA(rta); 657 dst->len = sizeof(u32); 658 } else 659 return -EINVAL; 660 661 return 0; 662 } 663 664 static void meta_int_apply_extras(struct meta_value *v, 665 struct meta_obj *dst) 666 { 667 if (v->hdr.shift) 668 dst->value >>= v->hdr.shift; 669 670 if (v->val) 671 dst->value &= v->val; 672 } 673 674 static int meta_int_dump(struct sk_buff *skb, struct meta_value *v, int tlv) 675 { 676 if (v->len == sizeof(unsigned long)) 677 RTA_PUT(skb, tlv, sizeof(unsigned long), &v->val); 678 else if (v->len == sizeof(u32)) { 679 u32 d = v->val; 680 RTA_PUT(skb, tlv, sizeof(d), &d); 681 } 682 683 return 0; 684 685 rtattr_failure: 686 return -1; 687 } 688 689 /************************************************************************** 690 * Type specific operations table 691 **************************************************************************/ 692 693 struct meta_type_ops 694 { 695 void (*destroy)(struct meta_value *); 696 int (*compare)(struct meta_obj *, struct meta_obj *); 697 int (*change)(struct meta_value *, struct rtattr *); 698 void (*apply_extras)(struct meta_value *, struct meta_obj *); 699 int (*dump)(struct sk_buff *, struct meta_value *, int); 700 }; 701 702 static struct meta_type_ops __meta_type_ops[TCF_META_TYPE_MAX+1] = { 703 [TCF_META_TYPE_VAR] = { 704 .destroy = meta_var_destroy, 705 .compare = meta_var_compare, 706 .change = meta_var_change, 707 .apply_extras = meta_var_apply_extras, 708 .dump = meta_var_dump 709 }, 710 [TCF_META_TYPE_INT] = { 711 .compare = meta_int_compare, 712 .change = meta_int_change, 713 .apply_extras = meta_int_apply_extras, 714 .dump = meta_int_dump 715 } 716 }; 717 718 static inline struct meta_type_ops * meta_type_ops(struct meta_value *v) 719 { 720 return &__meta_type_ops[meta_type(v)]; 721 } 722 723 /************************************************************************** 724 * Core 725 **************************************************************************/ 726 727 static inline int meta_get(struct sk_buff *skb, struct tcf_pkt_info *info, 728 struct meta_value *v, struct meta_obj *dst) 729 { 730 int err = 0; 731 732 if (meta_id(v) == TCF_META_ID_VALUE) { 733 dst->value = v->val; 734 dst->len = v->len; 735 return 0; 736 } 737 738 meta_ops(v)->get(skb, info, v, dst, &err); 739 if (err < 0) 740 return err; 741 742 if (meta_type_ops(v)->apply_extras) 743 meta_type_ops(v)->apply_extras(v, dst); 744 745 return 0; 746 } 747 748 static int em_meta_match(struct sk_buff *skb, struct tcf_ematch *m, 749 struct tcf_pkt_info *info) 750 { 751 int r; 752 struct meta_match *meta = (struct meta_match *) m->data; 753 struct meta_obj l_value, r_value; 754 755 if (meta_get(skb, info, &meta->lvalue, &l_value) < 0 || 756 meta_get(skb, info, &meta->rvalue, &r_value) < 0) 757 return 0; 758 759 r = meta_type_ops(&meta->lvalue)->compare(&l_value, &r_value); 760 761 switch (meta->lvalue.hdr.op) { 762 case TCF_EM_OPND_EQ: 763 return !r; 764 case TCF_EM_OPND_LT: 765 return r < 0; 766 case TCF_EM_OPND_GT: 767 return r > 0; 768 } 769 770 return 0; 771 } 772 773 static inline void meta_delete(struct meta_match *meta) 774 { 775 struct meta_type_ops *ops = meta_type_ops(&meta->lvalue); 776 777 if (ops && ops->destroy) { 778 ops->destroy(&meta->lvalue); 779 ops->destroy(&meta->rvalue); 780 } 781 782 kfree(meta); 783 } 784 785 static inline int meta_change_data(struct meta_value *dst, struct rtattr *rta) 786 { 787 if (rta) { 788 if (RTA_PAYLOAD(rta) == 0) 789 return -EINVAL; 790 791 return meta_type_ops(dst)->change(dst, rta); 792 } 793 794 return 0; 795 } 796 797 static inline int meta_is_supported(struct meta_value *val) 798 { 799 return (!meta_id(val) || meta_ops(val)->get); 800 } 801 802 static int em_meta_change(struct tcf_proto *tp, void *data, int len, 803 struct tcf_ematch *m) 804 { 805 int err = -EINVAL; 806 struct rtattr *tb[TCA_EM_META_MAX]; 807 struct tcf_meta_hdr *hdr; 808 struct meta_match *meta = NULL; 809 810 if (rtattr_parse(tb, TCA_EM_META_MAX, data, len) < 0) 811 goto errout; 812 813 if (tb[TCA_EM_META_HDR-1] == NULL || 814 RTA_PAYLOAD(tb[TCA_EM_META_HDR-1]) < sizeof(*hdr)) 815 goto errout; 816 hdr = RTA_DATA(tb[TCA_EM_META_HDR-1]); 817 818 if (TCF_META_TYPE(hdr->left.kind) != TCF_META_TYPE(hdr->right.kind) || 819 TCF_META_TYPE(hdr->left.kind) > TCF_META_TYPE_MAX || 820 TCF_META_ID(hdr->left.kind) > TCF_META_ID_MAX || 821 TCF_META_ID(hdr->right.kind) > TCF_META_ID_MAX) 822 goto errout; 823 824 meta = kmalloc(sizeof(*meta), GFP_KERNEL); 825 if (meta == NULL) 826 goto errout; 827 memset(meta, 0, sizeof(*meta)); 828 829 memcpy(&meta->lvalue.hdr, &hdr->left, sizeof(hdr->left)); 830 memcpy(&meta->rvalue.hdr, &hdr->right, sizeof(hdr->right)); 831 832 if (!meta_is_supported(&meta->lvalue) || 833 !meta_is_supported(&meta->rvalue)) { 834 err = -EOPNOTSUPP; 835 goto errout; 836 } 837 838 if (meta_change_data(&meta->lvalue, tb[TCA_EM_META_LVALUE-1]) < 0 || 839 meta_change_data(&meta->rvalue, tb[TCA_EM_META_RVALUE-1]) < 0) 840 goto errout; 841 842 m->datalen = sizeof(*meta); 843 m->data = (unsigned long) meta; 844 845 err = 0; 846 errout: 847 if (err && meta) 848 meta_delete(meta); 849 return err; 850 } 851 852 static void em_meta_destroy(struct tcf_proto *tp, struct tcf_ematch *m) 853 { 854 if (m) 855 meta_delete((struct meta_match *) m->data); 856 } 857 858 static int em_meta_dump(struct sk_buff *skb, struct tcf_ematch *em) 859 { 860 struct meta_match *meta = (struct meta_match *) em->data; 861 struct tcf_meta_hdr hdr; 862 struct meta_type_ops *ops; 863 864 memset(&hdr, 0, sizeof(hdr)); 865 memcpy(&hdr.left, &meta->lvalue.hdr, sizeof(hdr.left)); 866 memcpy(&hdr.right, &meta->rvalue.hdr, sizeof(hdr.right)); 867 868 RTA_PUT(skb, TCA_EM_META_HDR, sizeof(hdr), &hdr); 869 870 ops = meta_type_ops(&meta->lvalue); 871 if (ops->dump(skb, &meta->lvalue, TCA_EM_META_LVALUE) < 0 || 872 ops->dump(skb, &meta->rvalue, TCA_EM_META_RVALUE) < 0) 873 goto rtattr_failure; 874 875 return 0; 876 877 rtattr_failure: 878 return -1; 879 } 880 881 static struct tcf_ematch_ops em_meta_ops = { 882 .kind = TCF_EM_META, 883 .change = em_meta_change, 884 .match = em_meta_match, 885 .destroy = em_meta_destroy, 886 .dump = em_meta_dump, 887 .owner = THIS_MODULE, 888 .link = LIST_HEAD_INIT(em_meta_ops.link) 889 }; 890 891 static int __init init_em_meta(void) 892 { 893 return tcf_em_register(&em_meta_ops); 894 } 895 896 static void __exit exit_em_meta(void) 897 { 898 tcf_em_unregister(&em_meta_ops); 899 } 900 901 MODULE_LICENSE("GPL"); 902 903 module_init(init_em_meta); 904 module_exit(exit_em_meta); 905