1 /* 2 * This is a module which is used for queueing packets and communicating with 3 * userspace via nfetlink. 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_ALIGN(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 data_len = 0; 247 break; 248 249 case NFQNL_COPY_PACKET: 250 if ((entskb->ip_summed == CHECKSUM_PARTIAL || 251 entskb->ip_summed == CHECKSUM_COMPLETE) && 252 skb_checksum_help(entskb)) { 253 spin_unlock_bh(&queue->lock); 254 return NULL; 255 } 256 if (queue->copy_range == 0 257 || queue->copy_range > entskb->len) 258 data_len = entskb->len; 259 else 260 data_len = queue->copy_range; 261 262 size += nla_total_size(data_len); 263 break; 264 } 265 266 entry->id = queue->id_sequence++; 267 268 spin_unlock_bh(&queue->lock); 269 270 skb = alloc_skb(size, GFP_ATOMIC); 271 if (!skb) 272 goto nlmsg_failure; 273 274 old_tail = skb->tail; 275 nlh = NLMSG_PUT(skb, 0, 0, 276 NFNL_SUBSYS_QUEUE << 8 | NFQNL_MSG_PACKET, 277 sizeof(struct nfgenmsg)); 278 nfmsg = NLMSG_DATA(nlh); 279 nfmsg->nfgen_family = entry->pf; 280 nfmsg->version = NFNETLINK_V0; 281 nfmsg->res_id = htons(queue->queue_num); 282 283 pmsg.packet_id = htonl(entry->id); 284 pmsg.hw_protocol = entskb->protocol; 285 pmsg.hook = entry->hook; 286 287 NLA_PUT(skb, NFQA_PACKET_HDR, sizeof(pmsg), &pmsg); 288 289 indev = entry->indev; 290 if (indev) { 291 #ifndef CONFIG_BRIDGE_NETFILTER 292 NLA_PUT_BE32(skb, NFQA_IFINDEX_INDEV, htonl(indev->ifindex)); 293 #else 294 if (entry->pf == PF_BRIDGE) { 295 /* Case 1: indev is physical input device, we need to 296 * look for bridge group (when called from 297 * netfilter_bridge) */ 298 NLA_PUT_BE32(skb, NFQA_IFINDEX_PHYSINDEV, 299 htonl(indev->ifindex)); 300 /* this is the bridge group "brX" */ 301 NLA_PUT_BE32(skb, NFQA_IFINDEX_INDEV, 302 htonl(indev->br_port->br->dev->ifindex)); 303 } else { 304 /* Case 2: indev is bridge group, we need to look for 305 * physical device (when called from ipv4) */ 306 NLA_PUT_BE32(skb, NFQA_IFINDEX_INDEV, 307 htonl(indev->ifindex)); 308 if (entskb->nf_bridge && entskb->nf_bridge->physindev) 309 NLA_PUT_BE32(skb, NFQA_IFINDEX_PHYSINDEV, 310 htonl(entskb->nf_bridge->physindev->ifindex)); 311 } 312 #endif 313 } 314 315 if (outdev) { 316 #ifndef CONFIG_BRIDGE_NETFILTER 317 NLA_PUT_BE32(skb, NFQA_IFINDEX_OUTDEV, htonl(outdev->ifindex)); 318 #else 319 if (entry->pf == PF_BRIDGE) { 320 /* Case 1: outdev is physical output device, we need to 321 * look for bridge group (when called from 322 * netfilter_bridge) */ 323 NLA_PUT_BE32(skb, NFQA_IFINDEX_PHYSOUTDEV, 324 htonl(outdev->ifindex)); 325 /* this is the bridge group "brX" */ 326 NLA_PUT_BE32(skb, NFQA_IFINDEX_OUTDEV, 327 htonl(outdev->br_port->br->dev->ifindex)); 328 } else { 329 /* Case 2: outdev is bridge group, we need to look for 330 * physical output device (when called from ipv4) */ 331 NLA_PUT_BE32(skb, NFQA_IFINDEX_OUTDEV, 332 htonl(outdev->ifindex)); 333 if (entskb->nf_bridge && entskb->nf_bridge->physoutdev) 334 NLA_PUT_BE32(skb, NFQA_IFINDEX_PHYSOUTDEV, 335 htonl(entskb->nf_bridge->physoutdev->ifindex)); 336 } 337 #endif 338 } 339 340 if (entskb->mark) 341 NLA_PUT_BE32(skb, NFQA_MARK, htonl(entskb->mark)); 342 343 if (indev && entskb->dev) { 344 struct nfqnl_msg_packet_hw phw; 345 int len = dev_parse_header(entskb, phw.hw_addr); 346 if (len) { 347 phw.hw_addrlen = htons(len); 348 NLA_PUT(skb, NFQA_HWADDR, sizeof(phw), &phw); 349 } 350 } 351 352 if (entskb->tstamp.tv64) { 353 struct nfqnl_msg_packet_timestamp ts; 354 struct timeval tv = ktime_to_timeval(entskb->tstamp); 355 ts.sec = cpu_to_be64(tv.tv_sec); 356 ts.usec = cpu_to_be64(tv.tv_usec); 357 358 NLA_PUT(skb, NFQA_TIMESTAMP, sizeof(ts), &ts); 359 } 360 361 if (data_len) { 362 struct nlattr *nla; 363 int sz = nla_attr_size(data_len); 364 365 if (skb_tailroom(skb) < nla_total_size(data_len)) { 366 printk(KERN_WARNING "nf_queue: no tailroom!\n"); 367 goto nlmsg_failure; 368 } 369 370 nla = (struct nlattr *)skb_put(skb, nla_total_size(data_len)); 371 nla->nla_type = NFQA_PAYLOAD; 372 nla->nla_len = sz; 373 374 if (skb_copy_bits(entskb, 0, nla_data(nla), data_len)) 375 BUG(); 376 } 377 378 nlh->nlmsg_len = skb->tail - old_tail; 379 return skb; 380 381 nlmsg_failure: 382 nla_put_failure: 383 if (skb) 384 kfree_skb(skb); 385 if (net_ratelimit()) 386 printk(KERN_ERR "nf_queue: error creating packet message\n"); 387 return NULL; 388 } 389 390 static int 391 nfqnl_enqueue_packet(struct nf_queue_entry *entry, unsigned int queuenum) 392 { 393 struct sk_buff *nskb; 394 struct nfqnl_instance *queue; 395 int err; 396 397 /* rcu_read_lock()ed by nf_hook_slow() */ 398 queue = instance_lookup(queuenum); 399 if (!queue) 400 goto err_out; 401 402 if (queue->copy_mode == NFQNL_COPY_NONE) 403 goto err_out; 404 405 nskb = nfqnl_build_packet_message(queue, entry); 406 if (nskb == NULL) 407 goto err_out; 408 409 spin_lock_bh(&queue->lock); 410 411 if (!queue->peer_pid) 412 goto err_out_free_nskb; 413 414 if (queue->queue_total >= queue->queue_maxlen) { 415 queue->queue_dropped++; 416 if (net_ratelimit()) 417 printk(KERN_WARNING "nf_queue: full at %d entries, " 418 "dropping packets(s). Dropped: %d\n", 419 queue->queue_total, queue->queue_dropped); 420 goto err_out_free_nskb; 421 } 422 423 /* nfnetlink_unicast will either free the nskb or add it to a socket */ 424 err = nfnetlink_unicast(nskb, queue->peer_pid, MSG_DONTWAIT); 425 if (err < 0) { 426 queue->queue_user_dropped++; 427 goto err_out_unlock; 428 } 429 430 __enqueue_entry(queue, entry); 431 432 spin_unlock_bh(&queue->lock); 433 return 0; 434 435 err_out_free_nskb: 436 kfree_skb(nskb); 437 err_out_unlock: 438 spin_unlock_bh(&queue->lock); 439 err_out: 440 return -1; 441 } 442 443 static int 444 nfqnl_mangle(void *data, int data_len, struct nf_queue_entry *e) 445 { 446 struct sk_buff *nskb; 447 int diff; 448 449 diff = data_len - e->skb->len; 450 if (diff < 0) { 451 if (pskb_trim(e->skb, data_len)) 452 return -ENOMEM; 453 } else if (diff > 0) { 454 if (data_len > 0xFFFF) 455 return -EINVAL; 456 if (diff > skb_tailroom(e->skb)) { 457 nskb = skb_copy_expand(e->skb, 0, 458 diff - skb_tailroom(e->skb), 459 GFP_ATOMIC); 460 if (!nskb) { 461 printk(KERN_WARNING "nf_queue: OOM " 462 "in mangle, dropping packet\n"); 463 return -ENOMEM; 464 } 465 kfree_skb(e->skb); 466 e->skb = nskb; 467 } 468 skb_put(e->skb, diff); 469 } 470 if (!skb_make_writable(e->skb, data_len)) 471 return -ENOMEM; 472 skb_copy_to_linear_data(e->skb, data, data_len); 473 e->skb->ip_summed = CHECKSUM_NONE; 474 return 0; 475 } 476 477 static int 478 nfqnl_set_mode(struct nfqnl_instance *queue, 479 unsigned char mode, unsigned int range) 480 { 481 int status = 0; 482 483 spin_lock_bh(&queue->lock); 484 switch (mode) { 485 case NFQNL_COPY_NONE: 486 case NFQNL_COPY_META: 487 queue->copy_mode = mode; 488 queue->copy_range = 0; 489 break; 490 491 case NFQNL_COPY_PACKET: 492 queue->copy_mode = mode; 493 /* we're using struct nlattr which has 16bit nla_len */ 494 if (range > 0xffff) 495 queue->copy_range = 0xffff; 496 else 497 queue->copy_range = range; 498 break; 499 500 default: 501 status = -EINVAL; 502 503 } 504 spin_unlock_bh(&queue->lock); 505 506 return status; 507 } 508 509 static int 510 dev_cmp(struct nf_queue_entry *entry, unsigned long ifindex) 511 { 512 if (entry->indev) 513 if (entry->indev->ifindex == ifindex) 514 return 1; 515 if (entry->outdev) 516 if (entry->outdev->ifindex == ifindex) 517 return 1; 518 #ifdef CONFIG_BRIDGE_NETFILTER 519 if (entry->skb->nf_bridge) { 520 if (entry->skb->nf_bridge->physindev && 521 entry->skb->nf_bridge->physindev->ifindex == ifindex) 522 return 1; 523 if (entry->skb->nf_bridge->physoutdev && 524 entry->skb->nf_bridge->physoutdev->ifindex == ifindex) 525 return 1; 526 } 527 #endif 528 return 0; 529 } 530 531 /* drop all packets with either indev or outdev == ifindex from all queue 532 * instances */ 533 static void 534 nfqnl_dev_drop(int ifindex) 535 { 536 int i; 537 538 rcu_read_lock(); 539 540 for (i = 0; i < INSTANCE_BUCKETS; i++) { 541 struct hlist_node *tmp; 542 struct nfqnl_instance *inst; 543 struct hlist_head *head = &instance_table[i]; 544 545 hlist_for_each_entry_rcu(inst, tmp, head, hlist) 546 nfqnl_flush(inst, dev_cmp, ifindex); 547 } 548 549 rcu_read_unlock(); 550 } 551 552 #define RCV_SKB_FAIL(err) do { netlink_ack(skb, nlh, (err)); return; } while (0) 553 554 static int 555 nfqnl_rcv_dev_event(struct notifier_block *this, 556 unsigned long event, void *ptr) 557 { 558 struct net_device *dev = ptr; 559 560 if (dev->nd_net != &init_net) 561 return NOTIFY_DONE; 562 563 /* Drop any packets associated with the downed device */ 564 if (event == NETDEV_DOWN) 565 nfqnl_dev_drop(dev->ifindex); 566 return NOTIFY_DONE; 567 } 568 569 static struct notifier_block nfqnl_dev_notifier = { 570 .notifier_call = nfqnl_rcv_dev_event, 571 }; 572 573 static int 574 nfqnl_rcv_nl_event(struct notifier_block *this, 575 unsigned long event, void *ptr) 576 { 577 struct netlink_notify *n = ptr; 578 579 if (event == NETLINK_URELEASE && 580 n->protocol == NETLINK_NETFILTER && n->pid) { 581 int i; 582 583 /* destroy all instances for this pid */ 584 spin_lock(&instances_lock); 585 for (i = 0; i < INSTANCE_BUCKETS; i++) { 586 struct hlist_node *tmp, *t2; 587 struct nfqnl_instance *inst; 588 struct hlist_head *head = &instance_table[i]; 589 590 hlist_for_each_entry_safe(inst, tmp, t2, head, hlist) { 591 if ((n->net == &init_net) && 592 (n->pid == inst->peer_pid)) 593 __instance_destroy(inst); 594 } 595 } 596 spin_unlock(&instances_lock); 597 } 598 return NOTIFY_DONE; 599 } 600 601 static struct notifier_block nfqnl_rtnl_notifier = { 602 .notifier_call = nfqnl_rcv_nl_event, 603 }; 604 605 static const struct nla_policy nfqa_verdict_policy[NFQA_MAX+1] = { 606 [NFQA_VERDICT_HDR] = { .len = sizeof(struct nfqnl_msg_verdict_hdr) }, 607 [NFQA_MARK] = { .type = NLA_U32 }, 608 [NFQA_PAYLOAD] = { .type = NLA_UNSPEC }, 609 }; 610 611 static int 612 nfqnl_recv_verdict(struct sock *ctnl, struct sk_buff *skb, 613 struct nlmsghdr *nlh, struct nlattr *nfqa[]) 614 { 615 struct nfgenmsg *nfmsg = NLMSG_DATA(nlh); 616 u_int16_t queue_num = ntohs(nfmsg->res_id); 617 618 struct nfqnl_msg_verdict_hdr *vhdr; 619 struct nfqnl_instance *queue; 620 unsigned int verdict; 621 struct nf_queue_entry *entry; 622 int err; 623 624 rcu_read_lock(); 625 queue = instance_lookup(queue_num); 626 if (!queue) { 627 err = -ENODEV; 628 goto err_out_unlock; 629 } 630 631 if (queue->peer_pid != NETLINK_CB(skb).pid) { 632 err = -EPERM; 633 goto err_out_unlock; 634 } 635 636 if (!nfqa[NFQA_VERDICT_HDR]) { 637 err = -EINVAL; 638 goto err_out_unlock; 639 } 640 641 vhdr = nla_data(nfqa[NFQA_VERDICT_HDR]); 642 verdict = ntohl(vhdr->verdict); 643 644 if ((verdict & NF_VERDICT_MASK) > NF_MAX_VERDICT) { 645 err = -EINVAL; 646 goto err_out_unlock; 647 } 648 649 entry = find_dequeue_entry(queue, ntohl(vhdr->id)); 650 if (entry == NULL) { 651 err = -ENOENT; 652 goto err_out_unlock; 653 } 654 rcu_read_unlock(); 655 656 if (nfqa[NFQA_PAYLOAD]) { 657 if (nfqnl_mangle(nla_data(nfqa[NFQA_PAYLOAD]), 658 nla_len(nfqa[NFQA_PAYLOAD]), entry) < 0) 659 verdict = NF_DROP; 660 } 661 662 if (nfqa[NFQA_MARK]) 663 entry->skb->mark = ntohl(nla_get_be32(nfqa[NFQA_MARK])); 664 665 nf_reinject(entry, verdict); 666 return 0; 667 668 err_out_unlock: 669 rcu_read_unlock(); 670 return err; 671 } 672 673 static int 674 nfqnl_recv_unsupp(struct sock *ctnl, struct sk_buff *skb, 675 struct nlmsghdr *nlh, struct nlattr *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 struct nlmsghdr *nlh, struct nlattr *nfqa[]) 693 { 694 struct nfgenmsg *nfmsg = NLMSG_DATA(nlh); 695 u_int16_t queue_num = ntohs(nfmsg->res_id); 696 struct nfqnl_instance *queue; 697 struct nfqnl_msg_config_cmd *cmd = NULL; 698 int ret = 0; 699 700 if (nfqa[NFQA_CFG_CMD]) { 701 cmd = nla_data(nfqa[NFQA_CFG_CMD]); 702 703 /* Commands without queue context - might sleep */ 704 switch (cmd->command) { 705 case NFQNL_CFG_CMD_PF_BIND: 706 ret = nf_register_queue_handler(ntohs(cmd->pf), 707 &nfqh); 708 break; 709 case NFQNL_CFG_CMD_PF_UNBIND: 710 ret = nf_unregister_queue_handler(ntohs(cmd->pf), 711 &nfqh); 712 break; 713 default: 714 break; 715 } 716 717 if (ret < 0) 718 return ret; 719 } 720 721 rcu_read_lock(); 722 queue = instance_lookup(queue_num); 723 if (queue && queue->peer_pid != NETLINK_CB(skb).pid) { 724 ret = -EPERM; 725 goto err_out_unlock; 726 } 727 728 if (cmd != NULL) { 729 switch (cmd->command) { 730 case NFQNL_CFG_CMD_BIND: 731 if (queue) { 732 ret = -EBUSY; 733 goto err_out_unlock; 734 } 735 queue = instance_create(queue_num, NETLINK_CB(skb).pid); 736 if (IS_ERR(queue)) { 737 ret = PTR_ERR(queue); 738 goto err_out_unlock; 739 } 740 break; 741 case NFQNL_CFG_CMD_UNBIND: 742 if (!queue) { 743 ret = -ENODEV; 744 goto err_out_unlock; 745 } 746 instance_destroy(queue); 747 break; 748 case NFQNL_CFG_CMD_PF_BIND: 749 case NFQNL_CFG_CMD_PF_UNBIND: 750 break; 751 default: 752 ret = -ENOTSUPP; 753 break; 754 } 755 } 756 757 if (nfqa[NFQA_CFG_PARAMS]) { 758 struct nfqnl_msg_config_params *params; 759 760 if (!queue) { 761 ret = -ENODEV; 762 goto err_out_unlock; 763 } 764 params = nla_data(nfqa[NFQA_CFG_PARAMS]); 765 nfqnl_set_mode(queue, params->copy_mode, 766 ntohl(params->copy_range)); 767 } 768 769 if (nfqa[NFQA_CFG_QUEUE_MAXLEN]) { 770 __be32 *queue_maxlen; 771 772 if (!queue) { 773 ret = -ENODEV; 774 goto err_out_unlock; 775 } 776 queue_maxlen = nla_data(nfqa[NFQA_CFG_QUEUE_MAXLEN]); 777 spin_lock_bh(&queue->lock); 778 queue->queue_maxlen = ntohl(*queue_maxlen); 779 spin_unlock_bh(&queue->lock); 780 } 781 782 err_out_unlock: 783 rcu_read_unlock(); 784 return ret; 785 } 786 787 static const struct nfnl_callback nfqnl_cb[NFQNL_MSG_MAX] = { 788 [NFQNL_MSG_PACKET] = { .call = nfqnl_recv_unsupp, 789 .attr_count = NFQA_MAX, }, 790 [NFQNL_MSG_VERDICT] = { .call = nfqnl_recv_verdict, 791 .attr_count = NFQA_MAX, 792 .policy = nfqa_verdict_policy }, 793 [NFQNL_MSG_CONFIG] = { .call = nfqnl_recv_config, 794 .attr_count = NFQA_CFG_MAX, 795 .policy = nfqa_cfg_policy }, 796 }; 797 798 static const struct nfnetlink_subsystem nfqnl_subsys = { 799 .name = "nf_queue", 800 .subsys_id = NFNL_SUBSYS_QUEUE, 801 .cb_count = NFQNL_MSG_MAX, 802 .cb = nfqnl_cb, 803 }; 804 805 #ifdef CONFIG_PROC_FS 806 struct iter_state { 807 unsigned int bucket; 808 }; 809 810 static struct hlist_node *get_first(struct seq_file *seq) 811 { 812 struct iter_state *st = seq->private; 813 814 if (!st) 815 return NULL; 816 817 for (st->bucket = 0; st->bucket < INSTANCE_BUCKETS; st->bucket++) { 818 if (!hlist_empty(&instance_table[st->bucket])) 819 return instance_table[st->bucket].first; 820 } 821 return NULL; 822 } 823 824 static struct hlist_node *get_next(struct seq_file *seq, struct hlist_node *h) 825 { 826 struct iter_state *st = seq->private; 827 828 h = h->next; 829 while (!h) { 830 if (++st->bucket >= INSTANCE_BUCKETS) 831 return NULL; 832 833 h = instance_table[st->bucket].first; 834 } 835 return h; 836 } 837 838 static struct hlist_node *get_idx(struct seq_file *seq, loff_t pos) 839 { 840 struct hlist_node *head; 841 head = get_first(seq); 842 843 if (head) 844 while (pos && (head = get_next(seq, head))) 845 pos--; 846 return pos ? NULL : head; 847 } 848 849 static void *seq_start(struct seq_file *seq, loff_t *pos) 850 __acquires(instances_lock) 851 { 852 spin_lock(&instances_lock); 853 return get_idx(seq, *pos); 854 } 855 856 static void *seq_next(struct seq_file *s, void *v, loff_t *pos) 857 { 858 (*pos)++; 859 return get_next(s, v); 860 } 861 862 static void seq_stop(struct seq_file *s, void *v) 863 __releases(instances_lock) 864 { 865 spin_unlock(&instances_lock); 866 } 867 868 static int seq_show(struct seq_file *s, void *v) 869 { 870 const struct nfqnl_instance *inst = v; 871 872 return seq_printf(s, "%5d %6d %5d %1d %5d %5d %5d %8d %2d\n", 873 inst->queue_num, 874 inst->peer_pid, inst->queue_total, 875 inst->copy_mode, inst->copy_range, 876 inst->queue_dropped, inst->queue_user_dropped, 877 inst->id_sequence, 1); 878 } 879 880 static const struct seq_operations nfqnl_seq_ops = { 881 .start = seq_start, 882 .next = seq_next, 883 .stop = seq_stop, 884 .show = seq_show, 885 }; 886 887 static int nfqnl_open(struct inode *inode, struct file *file) 888 { 889 return seq_open_private(file, &nfqnl_seq_ops, 890 sizeof(struct iter_state)); 891 } 892 893 static const struct file_operations nfqnl_file_ops = { 894 .owner = THIS_MODULE, 895 .open = nfqnl_open, 896 .read = seq_read, 897 .llseek = seq_lseek, 898 .release = seq_release_private, 899 }; 900 901 #endif /* PROC_FS */ 902 903 static int __init nfnetlink_queue_init(void) 904 { 905 int i, status = -ENOMEM; 906 #ifdef CONFIG_PROC_FS 907 struct proc_dir_entry *proc_nfqueue; 908 #endif 909 910 for (i = 0; i < INSTANCE_BUCKETS; i++) 911 INIT_HLIST_HEAD(&instance_table[i]); 912 913 netlink_register_notifier(&nfqnl_rtnl_notifier); 914 status = nfnetlink_subsys_register(&nfqnl_subsys); 915 if (status < 0) { 916 printk(KERN_ERR "nf_queue: failed to create netlink socket\n"); 917 goto cleanup_netlink_notifier; 918 } 919 920 #ifdef CONFIG_PROC_FS 921 proc_nfqueue = create_proc_entry("nfnetlink_queue", 0440, 922 proc_net_netfilter); 923 if (!proc_nfqueue) 924 goto cleanup_subsys; 925 proc_nfqueue->proc_fops = &nfqnl_file_ops; 926 #endif 927 928 register_netdevice_notifier(&nfqnl_dev_notifier); 929 return status; 930 931 #ifdef CONFIG_PROC_FS 932 cleanup_subsys: 933 nfnetlink_subsys_unregister(&nfqnl_subsys); 934 #endif 935 cleanup_netlink_notifier: 936 netlink_unregister_notifier(&nfqnl_rtnl_notifier); 937 return status; 938 } 939 940 static void __exit nfnetlink_queue_fini(void) 941 { 942 nf_unregister_queue_handlers(&nfqh); 943 unregister_netdevice_notifier(&nfqnl_dev_notifier); 944 #ifdef CONFIG_PROC_FS 945 remove_proc_entry("nfnetlink_queue", proc_net_netfilter); 946 #endif 947 nfnetlink_subsys_unregister(&nfqnl_subsys); 948 netlink_unregister_notifier(&nfqnl_rtnl_notifier); 949 } 950 951 MODULE_DESCRIPTION("netfilter packet queue handler"); 952 MODULE_AUTHOR("Harald Welte <[email protected]>"); 953 MODULE_LICENSE("GPL"); 954 MODULE_ALIAS_NFNL_SUBSYS(NFNL_SUBSYS_QUEUE); 955 956 module_init(nfnetlink_queue_init); 957 module_exit(nfnetlink_queue_fini); 958