1 /* 2 * This is a module which is used for queueing packets and communicating with 3 * userspace via nfnetlink. 4 * 5 * (C) 2005 by Harald Welte <[email protected]> 6 * (C) 2007 by Patrick McHardy <[email protected]> 7 * 8 * Based on the old ipv4-only ip_queue.c: 9 * (C) 2000-2002 James Morris <[email protected]> 10 * (C) 2003-2005 Netfilter Core Team <[email protected]> 11 * 12 * This program is free software; you can redistribute it and/or modify 13 * it under the terms of the GNU General Public License version 2 as 14 * published by the Free Software Foundation. 15 * 16 */ 17 #include <linux/module.h> 18 #include <linux/skbuff.h> 19 #include <linux/init.h> 20 #include <linux/spinlock.h> 21 #include <linux/notifier.h> 22 #include <linux/netdevice.h> 23 #include <linux/netfilter.h> 24 #include <linux/proc_fs.h> 25 #include <linux/netfilter_ipv4.h> 26 #include <linux/netfilter_ipv6.h> 27 #include <linux/netfilter/nfnetlink.h> 28 #include <linux/netfilter/nfnetlink_queue.h> 29 #include <linux/list.h> 30 #include <net/sock.h> 31 #include <net/netfilter/nf_queue.h> 32 33 #include <asm/atomic.h> 34 35 #ifdef CONFIG_BRIDGE_NETFILTER 36 #include "../bridge/br_private.h" 37 #endif 38 39 #define NFQNL_QMAX_DEFAULT 1024 40 41 struct nfqnl_instance { 42 struct hlist_node hlist; /* global list of queues */ 43 struct rcu_head rcu; 44 45 int peer_pid; 46 unsigned int queue_maxlen; 47 unsigned int copy_range; 48 unsigned int queue_total; 49 unsigned int queue_dropped; 50 unsigned int queue_user_dropped; 51 52 unsigned int id_sequence; /* 'sequence' of pkt ids */ 53 54 u_int16_t queue_num; /* number of this queue */ 55 u_int8_t copy_mode; 56 57 spinlock_t lock; 58 59 struct list_head queue_list; /* packets in queue */ 60 }; 61 62 typedef int (*nfqnl_cmpfn)(struct nf_queue_entry *, unsigned long); 63 64 static DEFINE_SPINLOCK(instances_lock); 65 66 #define INSTANCE_BUCKETS 16 67 static struct hlist_head instance_table[INSTANCE_BUCKETS] __read_mostly; 68 69 static inline u_int8_t instance_hashfn(u_int16_t queue_num) 70 { 71 return ((queue_num >> 8) | queue_num) % INSTANCE_BUCKETS; 72 } 73 74 static struct nfqnl_instance * 75 instance_lookup(u_int16_t queue_num) 76 { 77 struct hlist_head *head; 78 struct hlist_node *pos; 79 struct nfqnl_instance *inst; 80 81 head = &instance_table[instance_hashfn(queue_num)]; 82 hlist_for_each_entry_rcu(inst, pos, head, hlist) { 83 if (inst->queue_num == queue_num) 84 return inst; 85 } 86 return NULL; 87 } 88 89 static struct nfqnl_instance * 90 instance_create(u_int16_t queue_num, int pid) 91 { 92 struct nfqnl_instance *inst; 93 unsigned int h; 94 int err; 95 96 spin_lock(&instances_lock); 97 if (instance_lookup(queue_num)) { 98 err = -EEXIST; 99 goto out_unlock; 100 } 101 102 inst = kzalloc(sizeof(*inst), GFP_ATOMIC); 103 if (!inst) { 104 err = -ENOMEM; 105 goto out_unlock; 106 } 107 108 inst->queue_num = queue_num; 109 inst->peer_pid = pid; 110 inst->queue_maxlen = NFQNL_QMAX_DEFAULT; 111 inst->copy_range = 0xfffff; 112 inst->copy_mode = NFQNL_COPY_NONE; 113 spin_lock_init(&inst->lock); 114 INIT_LIST_HEAD(&inst->queue_list); 115 INIT_RCU_HEAD(&inst->rcu); 116 117 if (!try_module_get(THIS_MODULE)) { 118 err = -EAGAIN; 119 goto out_free; 120 } 121 122 h = instance_hashfn(queue_num); 123 hlist_add_head_rcu(&inst->hlist, &instance_table[h]); 124 125 spin_unlock(&instances_lock); 126 127 return inst; 128 129 out_free: 130 kfree(inst); 131 out_unlock: 132 spin_unlock(&instances_lock); 133 return ERR_PTR(err); 134 } 135 136 static void nfqnl_flush(struct nfqnl_instance *queue, nfqnl_cmpfn cmpfn, 137 unsigned long data); 138 139 static void 140 instance_destroy_rcu(struct rcu_head *head) 141 { 142 struct nfqnl_instance *inst = container_of(head, struct nfqnl_instance, 143 rcu); 144 145 nfqnl_flush(inst, NULL, 0); 146 kfree(inst); 147 module_put(THIS_MODULE); 148 } 149 150 static void 151 __instance_destroy(struct nfqnl_instance *inst) 152 { 153 hlist_del_rcu(&inst->hlist); 154 call_rcu(&inst->rcu, instance_destroy_rcu); 155 } 156 157 static void 158 instance_destroy(struct nfqnl_instance *inst) 159 { 160 spin_lock(&instances_lock); 161 __instance_destroy(inst); 162 spin_unlock(&instances_lock); 163 } 164 165 static inline void 166 __enqueue_entry(struct nfqnl_instance *queue, struct nf_queue_entry *entry) 167 { 168 list_add_tail(&entry->list, &queue->queue_list); 169 queue->queue_total++; 170 } 171 172 static struct nf_queue_entry * 173 find_dequeue_entry(struct nfqnl_instance *queue, unsigned int id) 174 { 175 struct nf_queue_entry *entry = NULL, *i; 176 177 spin_lock_bh(&queue->lock); 178 179 list_for_each_entry(i, &queue->queue_list, list) { 180 if (i->id == id) { 181 entry = i; 182 break; 183 } 184 } 185 186 if (entry) { 187 list_del(&entry->list); 188 queue->queue_total--; 189 } 190 191 spin_unlock_bh(&queue->lock); 192 193 return entry; 194 } 195 196 static void 197 nfqnl_flush(struct nfqnl_instance *queue, nfqnl_cmpfn cmpfn, unsigned long data) 198 { 199 struct nf_queue_entry *entry, *next; 200 201 spin_lock_bh(&queue->lock); 202 list_for_each_entry_safe(entry, next, &queue->queue_list, list) { 203 if (!cmpfn || cmpfn(entry, data)) { 204 list_del(&entry->list); 205 queue->queue_total--; 206 nf_reinject(entry, NF_DROP); 207 } 208 } 209 spin_unlock_bh(&queue->lock); 210 } 211 212 static struct sk_buff * 213 nfqnl_build_packet_message(struct nfqnl_instance *queue, 214 struct nf_queue_entry *entry) 215 { 216 sk_buff_data_t old_tail; 217 size_t size; 218 size_t data_len = 0; 219 struct sk_buff *skb; 220 struct nfqnl_msg_packet_hdr pmsg; 221 struct nlmsghdr *nlh; 222 struct nfgenmsg *nfmsg; 223 struct sk_buff *entskb = entry->skb; 224 struct net_device *indev; 225 struct net_device *outdev; 226 227 size = NLMSG_SPACE(sizeof(struct nfgenmsg)) 228 + nla_total_size(sizeof(struct nfqnl_msg_packet_hdr)) 229 + nla_total_size(sizeof(u_int32_t)) /* ifindex */ 230 + nla_total_size(sizeof(u_int32_t)) /* ifindex */ 231 #ifdef CONFIG_BRIDGE_NETFILTER 232 + nla_total_size(sizeof(u_int32_t)) /* ifindex */ 233 + nla_total_size(sizeof(u_int32_t)) /* ifindex */ 234 #endif 235 + nla_total_size(sizeof(u_int32_t)) /* mark */ 236 + nla_total_size(sizeof(struct nfqnl_msg_packet_hw)) 237 + nla_total_size(sizeof(struct nfqnl_msg_packet_timestamp)); 238 239 outdev = entry->outdev; 240 241 spin_lock_bh(&queue->lock); 242 243 switch ((enum nfqnl_config_mode)queue->copy_mode) { 244 case NFQNL_COPY_META: 245 case NFQNL_COPY_NONE: 246 break; 247 248 case NFQNL_COPY_PACKET: 249 if ((entskb->ip_summed == CHECKSUM_PARTIAL || 250 entskb->ip_summed == CHECKSUM_COMPLETE) && 251 skb_checksum_help(entskb)) { 252 spin_unlock_bh(&queue->lock); 253 return NULL; 254 } 255 if (queue->copy_range == 0 256 || queue->copy_range > entskb->len) 257 data_len = entskb->len; 258 else 259 data_len = queue->copy_range; 260 261 size += nla_total_size(data_len); 262 break; 263 } 264 265 entry->id = queue->id_sequence++; 266 267 spin_unlock_bh(&queue->lock); 268 269 skb = alloc_skb(size, GFP_ATOMIC); 270 if (!skb) 271 goto nlmsg_failure; 272 273 old_tail = skb->tail; 274 nlh = NLMSG_PUT(skb, 0, 0, 275 NFNL_SUBSYS_QUEUE << 8 | NFQNL_MSG_PACKET, 276 sizeof(struct nfgenmsg)); 277 nfmsg = NLMSG_DATA(nlh); 278 nfmsg->nfgen_family = entry->pf; 279 nfmsg->version = NFNETLINK_V0; 280 nfmsg->res_id = htons(queue->queue_num); 281 282 pmsg.packet_id = htonl(entry->id); 283 pmsg.hw_protocol = entskb->protocol; 284 pmsg.hook = entry->hook; 285 286 NLA_PUT(skb, NFQA_PACKET_HDR, sizeof(pmsg), &pmsg); 287 288 indev = entry->indev; 289 if (indev) { 290 #ifndef CONFIG_BRIDGE_NETFILTER 291 NLA_PUT_BE32(skb, NFQA_IFINDEX_INDEV, htonl(indev->ifindex)); 292 #else 293 if (entry->pf == PF_BRIDGE) { 294 /* Case 1: indev is physical input device, we need to 295 * look for bridge group (when called from 296 * netfilter_bridge) */ 297 NLA_PUT_BE32(skb, NFQA_IFINDEX_PHYSINDEV, 298 htonl(indev->ifindex)); 299 /* this is the bridge group "brX" */ 300 NLA_PUT_BE32(skb, NFQA_IFINDEX_INDEV, 301 htonl(indev->br_port->br->dev->ifindex)); 302 } else { 303 /* Case 2: indev is bridge group, we need to look for 304 * physical device (when called from ipv4) */ 305 NLA_PUT_BE32(skb, NFQA_IFINDEX_INDEV, 306 htonl(indev->ifindex)); 307 if (entskb->nf_bridge && entskb->nf_bridge->physindev) 308 NLA_PUT_BE32(skb, NFQA_IFINDEX_PHYSINDEV, 309 htonl(entskb->nf_bridge->physindev->ifindex)); 310 } 311 #endif 312 } 313 314 if (outdev) { 315 #ifndef CONFIG_BRIDGE_NETFILTER 316 NLA_PUT_BE32(skb, NFQA_IFINDEX_OUTDEV, htonl(outdev->ifindex)); 317 #else 318 if (entry->pf == PF_BRIDGE) { 319 /* Case 1: outdev is physical output device, we need to 320 * look for bridge group (when called from 321 * netfilter_bridge) */ 322 NLA_PUT_BE32(skb, NFQA_IFINDEX_PHYSOUTDEV, 323 htonl(outdev->ifindex)); 324 /* this is the bridge group "brX" */ 325 NLA_PUT_BE32(skb, NFQA_IFINDEX_OUTDEV, 326 htonl(outdev->br_port->br->dev->ifindex)); 327 } else { 328 /* Case 2: outdev is bridge group, we need to look for 329 * physical output device (when called from ipv4) */ 330 NLA_PUT_BE32(skb, NFQA_IFINDEX_OUTDEV, 331 htonl(outdev->ifindex)); 332 if (entskb->nf_bridge && entskb->nf_bridge->physoutdev) 333 NLA_PUT_BE32(skb, NFQA_IFINDEX_PHYSOUTDEV, 334 htonl(entskb->nf_bridge->physoutdev->ifindex)); 335 } 336 #endif 337 } 338 339 if (entskb->mark) 340 NLA_PUT_BE32(skb, NFQA_MARK, htonl(entskb->mark)); 341 342 if (indev && entskb->dev) { 343 struct nfqnl_msg_packet_hw phw; 344 int len = dev_parse_header(entskb, phw.hw_addr); 345 if (len) { 346 phw.hw_addrlen = htons(len); 347 NLA_PUT(skb, NFQA_HWADDR, sizeof(phw), &phw); 348 } 349 } 350 351 if (entskb->tstamp.tv64) { 352 struct nfqnl_msg_packet_timestamp ts; 353 struct timeval tv = ktime_to_timeval(entskb->tstamp); 354 ts.sec = cpu_to_be64(tv.tv_sec); 355 ts.usec = cpu_to_be64(tv.tv_usec); 356 357 NLA_PUT(skb, NFQA_TIMESTAMP, sizeof(ts), &ts); 358 } 359 360 if (data_len) { 361 struct nlattr *nla; 362 int sz = nla_attr_size(data_len); 363 364 if (skb_tailroom(skb) < nla_total_size(data_len)) { 365 printk(KERN_WARNING "nf_queue: no tailroom!\n"); 366 goto nlmsg_failure; 367 } 368 369 nla = (struct nlattr *)skb_put(skb, nla_total_size(data_len)); 370 nla->nla_type = NFQA_PAYLOAD; 371 nla->nla_len = sz; 372 373 if (skb_copy_bits(entskb, 0, nla_data(nla), data_len)) 374 BUG(); 375 } 376 377 nlh->nlmsg_len = skb->tail - old_tail; 378 return skb; 379 380 nlmsg_failure: 381 nla_put_failure: 382 if (skb) 383 kfree_skb(skb); 384 if (net_ratelimit()) 385 printk(KERN_ERR "nf_queue: error creating packet message\n"); 386 return NULL; 387 } 388 389 static int 390 nfqnl_enqueue_packet(struct nf_queue_entry *entry, unsigned int queuenum) 391 { 392 struct sk_buff *nskb; 393 struct nfqnl_instance *queue; 394 int err; 395 396 /* rcu_read_lock()ed by nf_hook_slow() */ 397 queue = instance_lookup(queuenum); 398 if (!queue) 399 goto err_out; 400 401 if (queue->copy_mode == NFQNL_COPY_NONE) 402 goto err_out; 403 404 nskb = nfqnl_build_packet_message(queue, entry); 405 if (nskb == NULL) 406 goto err_out; 407 408 spin_lock_bh(&queue->lock); 409 410 if (!queue->peer_pid) 411 goto err_out_free_nskb; 412 413 if (queue->queue_total >= queue->queue_maxlen) { 414 queue->queue_dropped++; 415 if (net_ratelimit()) 416 printk(KERN_WARNING "nf_queue: full at %d entries, " 417 "dropping packets(s). Dropped: %d\n", 418 queue->queue_total, queue->queue_dropped); 419 goto err_out_free_nskb; 420 } 421 422 /* nfnetlink_unicast will either free the nskb or add it to a socket */ 423 err = nfnetlink_unicast(nskb, queue->peer_pid, MSG_DONTWAIT); 424 if (err < 0) { 425 queue->queue_user_dropped++; 426 goto err_out_unlock; 427 } 428 429 __enqueue_entry(queue, entry); 430 431 spin_unlock_bh(&queue->lock); 432 return 0; 433 434 err_out_free_nskb: 435 kfree_skb(nskb); 436 err_out_unlock: 437 spin_unlock_bh(&queue->lock); 438 err_out: 439 return -1; 440 } 441 442 static int 443 nfqnl_mangle(void *data, int data_len, struct nf_queue_entry *e) 444 { 445 struct sk_buff *nskb; 446 int diff; 447 448 diff = data_len - e->skb->len; 449 if (diff < 0) { 450 if (pskb_trim(e->skb, data_len)) 451 return -ENOMEM; 452 } else if (diff > 0) { 453 if (data_len > 0xFFFF) 454 return -EINVAL; 455 if (diff > skb_tailroom(e->skb)) { 456 nskb = skb_copy_expand(e->skb, skb_headroom(e->skb), 457 diff, GFP_ATOMIC); 458 if (!nskb) { 459 printk(KERN_WARNING "nf_queue: OOM " 460 "in mangle, dropping packet\n"); 461 return -ENOMEM; 462 } 463 kfree_skb(e->skb); 464 e->skb = nskb; 465 } 466 skb_put(e->skb, diff); 467 } 468 if (!skb_make_writable(e->skb, data_len)) 469 return -ENOMEM; 470 skb_copy_to_linear_data(e->skb, data, data_len); 471 e->skb->ip_summed = CHECKSUM_NONE; 472 return 0; 473 } 474 475 static int 476 nfqnl_set_mode(struct nfqnl_instance *queue, 477 unsigned char mode, unsigned int range) 478 { 479 int status = 0; 480 481 spin_lock_bh(&queue->lock); 482 switch (mode) { 483 case NFQNL_COPY_NONE: 484 case NFQNL_COPY_META: 485 queue->copy_mode = mode; 486 queue->copy_range = 0; 487 break; 488 489 case NFQNL_COPY_PACKET: 490 queue->copy_mode = mode; 491 /* we're using struct nlattr which has 16bit nla_len */ 492 if (range > 0xffff) 493 queue->copy_range = 0xffff; 494 else 495 queue->copy_range = range; 496 break; 497 498 default: 499 status = -EINVAL; 500 501 } 502 spin_unlock_bh(&queue->lock); 503 504 return status; 505 } 506 507 static int 508 dev_cmp(struct nf_queue_entry *entry, unsigned long ifindex) 509 { 510 if (entry->indev) 511 if (entry->indev->ifindex == ifindex) 512 return 1; 513 if (entry->outdev) 514 if (entry->outdev->ifindex == ifindex) 515 return 1; 516 #ifdef CONFIG_BRIDGE_NETFILTER 517 if (entry->skb->nf_bridge) { 518 if (entry->skb->nf_bridge->physindev && 519 entry->skb->nf_bridge->physindev->ifindex == ifindex) 520 return 1; 521 if (entry->skb->nf_bridge->physoutdev && 522 entry->skb->nf_bridge->physoutdev->ifindex == ifindex) 523 return 1; 524 } 525 #endif 526 return 0; 527 } 528 529 /* drop all packets with either indev or outdev == ifindex from all queue 530 * instances */ 531 static void 532 nfqnl_dev_drop(int ifindex) 533 { 534 int i; 535 536 rcu_read_lock(); 537 538 for (i = 0; i < INSTANCE_BUCKETS; i++) { 539 struct hlist_node *tmp; 540 struct nfqnl_instance *inst; 541 struct hlist_head *head = &instance_table[i]; 542 543 hlist_for_each_entry_rcu(inst, tmp, head, hlist) 544 nfqnl_flush(inst, dev_cmp, ifindex); 545 } 546 547 rcu_read_unlock(); 548 } 549 550 #define RCV_SKB_FAIL(err) do { netlink_ack(skb, nlh, (err)); return; } while (0) 551 552 static int 553 nfqnl_rcv_dev_event(struct notifier_block *this, 554 unsigned long event, void *ptr) 555 { 556 struct net_device *dev = ptr; 557 558 if (!net_eq(dev_net(dev), &init_net)) 559 return NOTIFY_DONE; 560 561 /* Drop any packets associated with the downed device */ 562 if (event == NETDEV_DOWN) 563 nfqnl_dev_drop(dev->ifindex); 564 return NOTIFY_DONE; 565 } 566 567 static struct notifier_block nfqnl_dev_notifier = { 568 .notifier_call = nfqnl_rcv_dev_event, 569 }; 570 571 static int 572 nfqnl_rcv_nl_event(struct notifier_block *this, 573 unsigned long event, void *ptr) 574 { 575 struct netlink_notify *n = ptr; 576 577 if (event == NETLINK_URELEASE && 578 n->protocol == NETLINK_NETFILTER && n->pid) { 579 int i; 580 581 /* destroy all instances for this pid */ 582 spin_lock(&instances_lock); 583 for (i = 0; i < INSTANCE_BUCKETS; i++) { 584 struct hlist_node *tmp, *t2; 585 struct nfqnl_instance *inst; 586 struct hlist_head *head = &instance_table[i]; 587 588 hlist_for_each_entry_safe(inst, tmp, t2, head, hlist) { 589 if ((n->net == &init_net) && 590 (n->pid == inst->peer_pid)) 591 __instance_destroy(inst); 592 } 593 } 594 spin_unlock(&instances_lock); 595 } 596 return NOTIFY_DONE; 597 } 598 599 static struct notifier_block nfqnl_rtnl_notifier = { 600 .notifier_call = nfqnl_rcv_nl_event, 601 }; 602 603 static const struct nla_policy nfqa_verdict_policy[NFQA_MAX+1] = { 604 [NFQA_VERDICT_HDR] = { .len = sizeof(struct nfqnl_msg_verdict_hdr) }, 605 [NFQA_MARK] = { .type = NLA_U32 }, 606 [NFQA_PAYLOAD] = { .type = NLA_UNSPEC }, 607 }; 608 609 static int 610 nfqnl_recv_verdict(struct sock *ctnl, struct sk_buff *skb, 611 const struct nlmsghdr *nlh, 612 const struct nlattr * const nfqa[]) 613 { 614 struct nfgenmsg *nfmsg = NLMSG_DATA(nlh); 615 u_int16_t queue_num = ntohs(nfmsg->res_id); 616 617 struct nfqnl_msg_verdict_hdr *vhdr; 618 struct nfqnl_instance *queue; 619 unsigned int verdict; 620 struct nf_queue_entry *entry; 621 int err; 622 623 rcu_read_lock(); 624 queue = instance_lookup(queue_num); 625 if (!queue) { 626 err = -ENODEV; 627 goto err_out_unlock; 628 } 629 630 if (queue->peer_pid != NETLINK_CB(skb).pid) { 631 err = -EPERM; 632 goto err_out_unlock; 633 } 634 635 if (!nfqa[NFQA_VERDICT_HDR]) { 636 err = -EINVAL; 637 goto err_out_unlock; 638 } 639 640 vhdr = nla_data(nfqa[NFQA_VERDICT_HDR]); 641 verdict = ntohl(vhdr->verdict); 642 643 if ((verdict & NF_VERDICT_MASK) > NF_MAX_VERDICT) { 644 err = -EINVAL; 645 goto err_out_unlock; 646 } 647 648 entry = find_dequeue_entry(queue, ntohl(vhdr->id)); 649 if (entry == NULL) { 650 err = -ENOENT; 651 goto err_out_unlock; 652 } 653 rcu_read_unlock(); 654 655 if (nfqa[NFQA_PAYLOAD]) { 656 if (nfqnl_mangle(nla_data(nfqa[NFQA_PAYLOAD]), 657 nla_len(nfqa[NFQA_PAYLOAD]), entry) < 0) 658 verdict = NF_DROP; 659 } 660 661 if (nfqa[NFQA_MARK]) 662 entry->skb->mark = ntohl(nla_get_be32(nfqa[NFQA_MARK])); 663 664 nf_reinject(entry, verdict); 665 return 0; 666 667 err_out_unlock: 668 rcu_read_unlock(); 669 return err; 670 } 671 672 static int 673 nfqnl_recv_unsupp(struct sock *ctnl, struct sk_buff *skb, 674 const struct nlmsghdr *nlh, 675 const struct nlattr * const nfqa[]) 676 { 677 return -ENOTSUPP; 678 } 679 680 static const struct nla_policy nfqa_cfg_policy[NFQA_CFG_MAX+1] = { 681 [NFQA_CFG_CMD] = { .len = sizeof(struct nfqnl_msg_config_cmd) }, 682 [NFQA_CFG_PARAMS] = { .len = sizeof(struct nfqnl_msg_config_params) }, 683 }; 684 685 static const struct nf_queue_handler nfqh = { 686 .name = "nf_queue", 687 .outfn = &nfqnl_enqueue_packet, 688 }; 689 690 static int 691 nfqnl_recv_config(struct sock *ctnl, struct sk_buff *skb, 692 const struct nlmsghdr *nlh, 693 const struct nlattr * const nfqa[]) 694 { 695 struct nfgenmsg *nfmsg = NLMSG_DATA(nlh); 696 u_int16_t queue_num = ntohs(nfmsg->res_id); 697 struct nfqnl_instance *queue; 698 struct nfqnl_msg_config_cmd *cmd = NULL; 699 int ret = 0; 700 701 if (nfqa[NFQA_CFG_CMD]) { 702 cmd = nla_data(nfqa[NFQA_CFG_CMD]); 703 704 /* Commands without queue context - might sleep */ 705 switch (cmd->command) { 706 case NFQNL_CFG_CMD_PF_BIND: 707 return nf_register_queue_handler(ntohs(cmd->pf), 708 &nfqh); 709 case NFQNL_CFG_CMD_PF_UNBIND: 710 return nf_unregister_queue_handler(ntohs(cmd->pf), 711 &nfqh); 712 } 713 } 714 715 rcu_read_lock(); 716 queue = instance_lookup(queue_num); 717 if (queue && queue->peer_pid != NETLINK_CB(skb).pid) { 718 ret = -EPERM; 719 goto err_out_unlock; 720 } 721 722 if (cmd != NULL) { 723 switch (cmd->command) { 724 case NFQNL_CFG_CMD_BIND: 725 if (queue) { 726 ret = -EBUSY; 727 goto err_out_unlock; 728 } 729 queue = instance_create(queue_num, NETLINK_CB(skb).pid); 730 if (IS_ERR(queue)) { 731 ret = PTR_ERR(queue); 732 goto err_out_unlock; 733 } 734 break; 735 case NFQNL_CFG_CMD_UNBIND: 736 if (!queue) { 737 ret = -ENODEV; 738 goto err_out_unlock; 739 } 740 instance_destroy(queue); 741 break; 742 case NFQNL_CFG_CMD_PF_BIND: 743 case NFQNL_CFG_CMD_PF_UNBIND: 744 break; 745 default: 746 ret = -ENOTSUPP; 747 break; 748 } 749 } 750 751 if (nfqa[NFQA_CFG_PARAMS]) { 752 struct nfqnl_msg_config_params *params; 753 754 if (!queue) { 755 ret = -ENODEV; 756 goto err_out_unlock; 757 } 758 params = nla_data(nfqa[NFQA_CFG_PARAMS]); 759 nfqnl_set_mode(queue, params->copy_mode, 760 ntohl(params->copy_range)); 761 } 762 763 if (nfqa[NFQA_CFG_QUEUE_MAXLEN]) { 764 __be32 *queue_maxlen; 765 766 if (!queue) { 767 ret = -ENODEV; 768 goto err_out_unlock; 769 } 770 queue_maxlen = nla_data(nfqa[NFQA_CFG_QUEUE_MAXLEN]); 771 spin_lock_bh(&queue->lock); 772 queue->queue_maxlen = ntohl(*queue_maxlen); 773 spin_unlock_bh(&queue->lock); 774 } 775 776 err_out_unlock: 777 rcu_read_unlock(); 778 return ret; 779 } 780 781 static const struct nfnl_callback nfqnl_cb[NFQNL_MSG_MAX] = { 782 [NFQNL_MSG_PACKET] = { .call = nfqnl_recv_unsupp, 783 .attr_count = NFQA_MAX, }, 784 [NFQNL_MSG_VERDICT] = { .call = nfqnl_recv_verdict, 785 .attr_count = NFQA_MAX, 786 .policy = nfqa_verdict_policy }, 787 [NFQNL_MSG_CONFIG] = { .call = nfqnl_recv_config, 788 .attr_count = NFQA_CFG_MAX, 789 .policy = nfqa_cfg_policy }, 790 }; 791 792 static const struct nfnetlink_subsystem nfqnl_subsys = { 793 .name = "nf_queue", 794 .subsys_id = NFNL_SUBSYS_QUEUE, 795 .cb_count = NFQNL_MSG_MAX, 796 .cb = nfqnl_cb, 797 }; 798 799 #ifdef CONFIG_PROC_FS 800 struct iter_state { 801 unsigned int bucket; 802 }; 803 804 static struct hlist_node *get_first(struct seq_file *seq) 805 { 806 struct iter_state *st = seq->private; 807 808 if (!st) 809 return NULL; 810 811 for (st->bucket = 0; st->bucket < INSTANCE_BUCKETS; st->bucket++) { 812 if (!hlist_empty(&instance_table[st->bucket])) 813 return instance_table[st->bucket].first; 814 } 815 return NULL; 816 } 817 818 static struct hlist_node *get_next(struct seq_file *seq, struct hlist_node *h) 819 { 820 struct iter_state *st = seq->private; 821 822 h = h->next; 823 while (!h) { 824 if (++st->bucket >= INSTANCE_BUCKETS) 825 return NULL; 826 827 h = instance_table[st->bucket].first; 828 } 829 return h; 830 } 831 832 static struct hlist_node *get_idx(struct seq_file *seq, loff_t pos) 833 { 834 struct hlist_node *head; 835 head = get_first(seq); 836 837 if (head) 838 while (pos && (head = get_next(seq, head))) 839 pos--; 840 return pos ? NULL : head; 841 } 842 843 static void *seq_start(struct seq_file *seq, loff_t *pos) 844 __acquires(instances_lock) 845 { 846 spin_lock(&instances_lock); 847 return get_idx(seq, *pos); 848 } 849 850 static void *seq_next(struct seq_file *s, void *v, loff_t *pos) 851 { 852 (*pos)++; 853 return get_next(s, v); 854 } 855 856 static void seq_stop(struct seq_file *s, void *v) 857 __releases(instances_lock) 858 { 859 spin_unlock(&instances_lock); 860 } 861 862 static int seq_show(struct seq_file *s, void *v) 863 { 864 const struct nfqnl_instance *inst = v; 865 866 return seq_printf(s, "%5d %6d %5d %1d %5d %5d %5d %8d %2d\n", 867 inst->queue_num, 868 inst->peer_pid, inst->queue_total, 869 inst->copy_mode, inst->copy_range, 870 inst->queue_dropped, inst->queue_user_dropped, 871 inst->id_sequence, 1); 872 } 873 874 static const struct seq_operations nfqnl_seq_ops = { 875 .start = seq_start, 876 .next = seq_next, 877 .stop = seq_stop, 878 .show = seq_show, 879 }; 880 881 static int nfqnl_open(struct inode *inode, struct file *file) 882 { 883 return seq_open_private(file, &nfqnl_seq_ops, 884 sizeof(struct iter_state)); 885 } 886 887 static const struct file_operations nfqnl_file_ops = { 888 .owner = THIS_MODULE, 889 .open = nfqnl_open, 890 .read = seq_read, 891 .llseek = seq_lseek, 892 .release = seq_release_private, 893 }; 894 895 #endif /* PROC_FS */ 896 897 static int __init nfnetlink_queue_init(void) 898 { 899 int i, status = -ENOMEM; 900 901 for (i = 0; i < INSTANCE_BUCKETS; i++) 902 INIT_HLIST_HEAD(&instance_table[i]); 903 904 netlink_register_notifier(&nfqnl_rtnl_notifier); 905 status = nfnetlink_subsys_register(&nfqnl_subsys); 906 if (status < 0) { 907 printk(KERN_ERR "nf_queue: failed to create netlink socket\n"); 908 goto cleanup_netlink_notifier; 909 } 910 911 #ifdef CONFIG_PROC_FS 912 if (!proc_create("nfnetlink_queue", 0440, 913 proc_net_netfilter, &nfqnl_file_ops)) 914 goto cleanup_subsys; 915 #endif 916 917 register_netdevice_notifier(&nfqnl_dev_notifier); 918 return status; 919 920 #ifdef CONFIG_PROC_FS 921 cleanup_subsys: 922 nfnetlink_subsys_unregister(&nfqnl_subsys); 923 #endif 924 cleanup_netlink_notifier: 925 netlink_unregister_notifier(&nfqnl_rtnl_notifier); 926 return status; 927 } 928 929 static void __exit nfnetlink_queue_fini(void) 930 { 931 nf_unregister_queue_handlers(&nfqh); 932 unregister_netdevice_notifier(&nfqnl_dev_notifier); 933 #ifdef CONFIG_PROC_FS 934 remove_proc_entry("nfnetlink_queue", proc_net_netfilter); 935 #endif 936 nfnetlink_subsys_unregister(&nfqnl_subsys); 937 netlink_unregister_notifier(&nfqnl_rtnl_notifier); 938 939 rcu_barrier(); /* Wait for completion of call_rcu()'s */ 940 } 941 942 MODULE_DESCRIPTION("netfilter packet queue handler"); 943 MODULE_AUTHOR("Harald Welte <[email protected]>"); 944 MODULE_LICENSE("GPL"); 945 MODULE_ALIAS_NFNL_SUBSYS(NFNL_SUBSYS_QUEUE); 946 947 module_init(nfnetlink_queue_init); 948 module_exit(nfnetlink_queue_fini); 949