1 // SPDX-License-Identifier: GPL-2.0-only 2 /* 3 * This is a module which is used for queueing packets and communicating with 4 * userspace via nfnetlink. 5 * 6 * (C) 2005 by Harald Welte <[email protected]> 7 * (C) 2007 by Patrick McHardy <[email protected]> 8 * 9 * Based on the old ipv4-only ip_queue.c: 10 * (C) 2000-2002 James Morris <[email protected]> 11 * (C) 2003-2005 Netfilter Core Team <[email protected]> 12 */ 13 14 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt 15 16 #include <linux/module.h> 17 #include <linux/skbuff.h> 18 #include <linux/init.h> 19 #include <linux/spinlock.h> 20 #include <linux/slab.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_bridge.h> 28 #include <linux/netfilter/nfnetlink.h> 29 #include <linux/netfilter/nfnetlink_queue.h> 30 #include <linux/netfilter/nf_conntrack_common.h> 31 #include <linux/list.h> 32 #include <linux/cgroup-defs.h> 33 #include <net/gso.h> 34 #include <net/sock.h> 35 #include <net/tcp_states.h> 36 #include <net/netfilter/nf_queue.h> 37 #include <net/netns/generic.h> 38 39 #include <linux/atomic.h> 40 41 #if IS_ENABLED(CONFIG_BRIDGE_NETFILTER) 42 #include "../bridge/br_private.h" 43 #endif 44 45 #if IS_ENABLED(CONFIG_NF_CONNTRACK) 46 #include <net/netfilter/nf_conntrack.h> 47 #endif 48 49 #define NFQNL_QMAX_DEFAULT 1024 50 51 /* We're using struct nlattr which has 16bit nla_len. Note that nla_len 52 * includes the header length. Thus, the maximum packet length that we 53 * support is 65531 bytes. We send truncated packets if the specified length 54 * is larger than that. Userspace can check for presence of NFQA_CAP_LEN 55 * attribute to detect truncation. 56 */ 57 #define NFQNL_MAX_COPY_RANGE (0xffff - NLA_HDRLEN) 58 59 struct nfqnl_instance { 60 struct hlist_node hlist; /* global list of queues */ 61 struct rcu_head rcu; 62 63 u32 peer_portid; 64 unsigned int queue_maxlen; 65 unsigned int copy_range; 66 unsigned int queue_dropped; 67 unsigned int queue_user_dropped; 68 69 70 u_int16_t queue_num; /* number of this queue */ 71 u_int8_t copy_mode; 72 u_int32_t flags; /* Set using NFQA_CFG_FLAGS */ 73 /* 74 * Following fields are dirtied for each queued packet, 75 * keep them in same cache line if possible. 76 */ 77 spinlock_t lock ____cacheline_aligned_in_smp; 78 unsigned int queue_total; 79 unsigned int id_sequence; /* 'sequence' of pkt ids */ 80 struct list_head queue_list; /* packets in queue */ 81 }; 82 83 typedef int (*nfqnl_cmpfn)(struct nf_queue_entry *, unsigned long); 84 85 static unsigned int nfnl_queue_net_id __read_mostly; 86 87 #define INSTANCE_BUCKETS 16 88 struct nfnl_queue_net { 89 spinlock_t instances_lock; 90 struct hlist_head instance_table[INSTANCE_BUCKETS]; 91 }; 92 93 static struct nfnl_queue_net *nfnl_queue_pernet(struct net *net) 94 { 95 return net_generic(net, nfnl_queue_net_id); 96 } 97 98 static inline u_int8_t instance_hashfn(u_int16_t queue_num) 99 { 100 return ((queue_num >> 8) ^ queue_num) % INSTANCE_BUCKETS; 101 } 102 103 static struct nfqnl_instance * 104 instance_lookup(struct nfnl_queue_net *q, u_int16_t queue_num) 105 { 106 struct hlist_head *head; 107 struct nfqnl_instance *inst; 108 109 head = &q->instance_table[instance_hashfn(queue_num)]; 110 hlist_for_each_entry_rcu(inst, head, hlist) { 111 if (inst->queue_num == queue_num) 112 return inst; 113 } 114 return NULL; 115 } 116 117 static struct nfqnl_instance * 118 instance_create(struct nfnl_queue_net *q, u_int16_t queue_num, u32 portid) 119 { 120 struct nfqnl_instance *inst; 121 unsigned int h; 122 int err; 123 124 spin_lock(&q->instances_lock); 125 if (instance_lookup(q, queue_num)) { 126 err = -EEXIST; 127 goto out_unlock; 128 } 129 130 inst = kzalloc(sizeof(*inst), GFP_ATOMIC); 131 if (!inst) { 132 err = -ENOMEM; 133 goto out_unlock; 134 } 135 136 inst->queue_num = queue_num; 137 inst->peer_portid = portid; 138 inst->queue_maxlen = NFQNL_QMAX_DEFAULT; 139 inst->copy_range = NFQNL_MAX_COPY_RANGE; 140 inst->copy_mode = NFQNL_COPY_NONE; 141 spin_lock_init(&inst->lock); 142 INIT_LIST_HEAD(&inst->queue_list); 143 144 if (!try_module_get(THIS_MODULE)) { 145 err = -EAGAIN; 146 goto out_free; 147 } 148 149 h = instance_hashfn(queue_num); 150 hlist_add_head_rcu(&inst->hlist, &q->instance_table[h]); 151 152 spin_unlock(&q->instances_lock); 153 154 return inst; 155 156 out_free: 157 kfree(inst); 158 out_unlock: 159 spin_unlock(&q->instances_lock); 160 return ERR_PTR(err); 161 } 162 163 static void nfqnl_flush(struct nfqnl_instance *queue, nfqnl_cmpfn cmpfn, 164 unsigned long data); 165 166 static void 167 instance_destroy_rcu(struct rcu_head *head) 168 { 169 struct nfqnl_instance *inst = container_of(head, struct nfqnl_instance, 170 rcu); 171 172 nfqnl_flush(inst, NULL, 0); 173 kfree(inst); 174 module_put(THIS_MODULE); 175 } 176 177 static void 178 __instance_destroy(struct nfqnl_instance *inst) 179 { 180 hlist_del_rcu(&inst->hlist); 181 call_rcu(&inst->rcu, instance_destroy_rcu); 182 } 183 184 static void 185 instance_destroy(struct nfnl_queue_net *q, struct nfqnl_instance *inst) 186 { 187 spin_lock(&q->instances_lock); 188 __instance_destroy(inst); 189 spin_unlock(&q->instances_lock); 190 } 191 192 static inline void 193 __enqueue_entry(struct nfqnl_instance *queue, struct nf_queue_entry *entry) 194 { 195 list_add_tail(&entry->list, &queue->queue_list); 196 queue->queue_total++; 197 } 198 199 static void 200 __dequeue_entry(struct nfqnl_instance *queue, struct nf_queue_entry *entry) 201 { 202 list_del(&entry->list); 203 queue->queue_total--; 204 } 205 206 static struct nf_queue_entry * 207 find_dequeue_entry(struct nfqnl_instance *queue, unsigned int id) 208 { 209 struct nf_queue_entry *entry = NULL, *i; 210 211 spin_lock_bh(&queue->lock); 212 213 list_for_each_entry(i, &queue->queue_list, list) { 214 if (i->id == id) { 215 entry = i; 216 break; 217 } 218 } 219 220 if (entry) 221 __dequeue_entry(queue, entry); 222 223 spin_unlock_bh(&queue->lock); 224 225 return entry; 226 } 227 228 static void nfqnl_reinject(struct nf_queue_entry *entry, unsigned int verdict) 229 { 230 const struct nf_ct_hook *ct_hook; 231 232 if (verdict == NF_ACCEPT || 233 verdict == NF_REPEAT || 234 verdict == NF_STOP) { 235 unsigned int ct_verdict = verdict; 236 237 rcu_read_lock(); 238 ct_hook = rcu_dereference(nf_ct_hook); 239 if (ct_hook) 240 ct_verdict = ct_hook->update(entry->state.net, entry->skb); 241 rcu_read_unlock(); 242 243 switch (ct_verdict & NF_VERDICT_MASK) { 244 case NF_ACCEPT: 245 /* follow userspace verdict, could be REPEAT */ 246 break; 247 case NF_STOLEN: 248 nf_queue_entry_free(entry); 249 return; 250 default: 251 verdict = ct_verdict & NF_VERDICT_MASK; 252 break; 253 } 254 } 255 nf_reinject(entry, verdict); 256 } 257 258 static void 259 nfqnl_flush(struct nfqnl_instance *queue, nfqnl_cmpfn cmpfn, unsigned long data) 260 { 261 struct nf_queue_entry *entry, *next; 262 263 spin_lock_bh(&queue->lock); 264 list_for_each_entry_safe(entry, next, &queue->queue_list, list) { 265 if (!cmpfn || cmpfn(entry, data)) { 266 list_del(&entry->list); 267 queue->queue_total--; 268 nfqnl_reinject(entry, NF_DROP); 269 } 270 } 271 spin_unlock_bh(&queue->lock); 272 } 273 274 static int 275 nfqnl_put_packet_info(struct sk_buff *nlskb, struct sk_buff *packet, 276 bool csum_verify) 277 { 278 __u32 flags = 0; 279 280 if (packet->ip_summed == CHECKSUM_PARTIAL) 281 flags = NFQA_SKB_CSUMNOTREADY; 282 else if (csum_verify) 283 flags = NFQA_SKB_CSUM_NOTVERIFIED; 284 285 if (skb_is_gso(packet)) 286 flags |= NFQA_SKB_GSO; 287 288 return flags ? nla_put_be32(nlskb, NFQA_SKB_INFO, htonl(flags)) : 0; 289 } 290 291 static int nfqnl_put_sk_uidgid(struct sk_buff *skb, struct sock *sk) 292 { 293 const struct cred *cred; 294 295 if (!sk_fullsock(sk)) 296 return 0; 297 298 read_lock_bh(&sk->sk_callback_lock); 299 if (sk->sk_socket && sk->sk_socket->file) { 300 cred = sk->sk_socket->file->f_cred; 301 if (nla_put_be32(skb, NFQA_UID, 302 htonl(from_kuid_munged(&init_user_ns, cred->fsuid)))) 303 goto nla_put_failure; 304 if (nla_put_be32(skb, NFQA_GID, 305 htonl(from_kgid_munged(&init_user_ns, cred->fsgid)))) 306 goto nla_put_failure; 307 } 308 read_unlock_bh(&sk->sk_callback_lock); 309 return 0; 310 311 nla_put_failure: 312 read_unlock_bh(&sk->sk_callback_lock); 313 return -1; 314 } 315 316 static int nfqnl_put_sk_classid(struct sk_buff *skb, struct sock *sk) 317 { 318 #if IS_ENABLED(CONFIG_CGROUP_NET_CLASSID) 319 if (sk && sk_fullsock(sk)) { 320 u32 classid = sock_cgroup_classid(&sk->sk_cgrp_data); 321 322 if (classid && nla_put_be32(skb, NFQA_CGROUP_CLASSID, htonl(classid))) 323 return -1; 324 } 325 #endif 326 return 0; 327 } 328 329 static u32 nfqnl_get_sk_secctx(struct sk_buff *skb, char **secdata) 330 { 331 u32 seclen = 0; 332 #if IS_ENABLED(CONFIG_NETWORK_SECMARK) 333 if (!skb || !sk_fullsock(skb->sk)) 334 return 0; 335 336 read_lock_bh(&skb->sk->sk_callback_lock); 337 338 if (skb->secmark) 339 security_secid_to_secctx(skb->secmark, secdata, &seclen); 340 341 read_unlock_bh(&skb->sk->sk_callback_lock); 342 #endif 343 return seclen; 344 } 345 346 static u32 nfqnl_get_bridge_size(struct nf_queue_entry *entry) 347 { 348 struct sk_buff *entskb = entry->skb; 349 u32 nlalen = 0; 350 351 if (entry->state.pf != PF_BRIDGE || !skb_mac_header_was_set(entskb)) 352 return 0; 353 354 if (skb_vlan_tag_present(entskb)) 355 nlalen += nla_total_size(nla_total_size(sizeof(__be16)) + 356 nla_total_size(sizeof(__be16))); 357 358 if (entskb->network_header > entskb->mac_header) 359 nlalen += nla_total_size((entskb->network_header - 360 entskb->mac_header)); 361 362 return nlalen; 363 } 364 365 static int nfqnl_put_bridge(struct nf_queue_entry *entry, struct sk_buff *skb) 366 { 367 struct sk_buff *entskb = entry->skb; 368 369 if (entry->state.pf != PF_BRIDGE || !skb_mac_header_was_set(entskb)) 370 return 0; 371 372 if (skb_vlan_tag_present(entskb)) { 373 struct nlattr *nest; 374 375 nest = nla_nest_start(skb, NFQA_VLAN); 376 if (!nest) 377 goto nla_put_failure; 378 379 if (nla_put_be16(skb, NFQA_VLAN_TCI, htons(entskb->vlan_tci)) || 380 nla_put_be16(skb, NFQA_VLAN_PROTO, entskb->vlan_proto)) 381 goto nla_put_failure; 382 383 nla_nest_end(skb, nest); 384 } 385 386 if (entskb->mac_header < entskb->network_header) { 387 int len = (int)(entskb->network_header - entskb->mac_header); 388 389 if (nla_put(skb, NFQA_L2HDR, len, skb_mac_header(entskb))) 390 goto nla_put_failure; 391 } 392 393 return 0; 394 395 nla_put_failure: 396 return -1; 397 } 398 399 static struct sk_buff * 400 nfqnl_build_packet_message(struct net *net, struct nfqnl_instance *queue, 401 struct nf_queue_entry *entry, 402 __be32 **packet_id_ptr) 403 { 404 size_t size; 405 size_t data_len = 0, cap_len = 0; 406 unsigned int hlen = 0; 407 struct sk_buff *skb; 408 struct nlattr *nla; 409 struct nfqnl_msg_packet_hdr *pmsg; 410 struct nlmsghdr *nlh; 411 struct sk_buff *entskb = entry->skb; 412 struct net_device *indev; 413 struct net_device *outdev; 414 struct nf_conn *ct = NULL; 415 enum ip_conntrack_info ctinfo = 0; 416 const struct nfnl_ct_hook *nfnl_ct; 417 bool csum_verify; 418 char *secdata = NULL; 419 u32 seclen = 0; 420 ktime_t tstamp; 421 422 size = nlmsg_total_size(sizeof(struct nfgenmsg)) 423 + nla_total_size(sizeof(struct nfqnl_msg_packet_hdr)) 424 + nla_total_size(sizeof(u_int32_t)) /* ifindex */ 425 + nla_total_size(sizeof(u_int32_t)) /* ifindex */ 426 #if IS_ENABLED(CONFIG_BRIDGE_NETFILTER) 427 + nla_total_size(sizeof(u_int32_t)) /* ifindex */ 428 + nla_total_size(sizeof(u_int32_t)) /* ifindex */ 429 #endif 430 + nla_total_size(sizeof(u_int32_t)) /* mark */ 431 + nla_total_size(sizeof(u_int32_t)) /* priority */ 432 + nla_total_size(sizeof(struct nfqnl_msg_packet_hw)) 433 + nla_total_size(sizeof(u_int32_t)) /* skbinfo */ 434 #if IS_ENABLED(CONFIG_CGROUP_NET_CLASSID) 435 + nla_total_size(sizeof(u_int32_t)) /* classid */ 436 #endif 437 + nla_total_size(sizeof(u_int32_t)); /* cap_len */ 438 439 tstamp = skb_tstamp_cond(entskb, false); 440 if (tstamp) 441 size += nla_total_size(sizeof(struct nfqnl_msg_packet_timestamp)); 442 443 size += nfqnl_get_bridge_size(entry); 444 445 if (entry->state.hook <= NF_INET_FORWARD || 446 (entry->state.hook == NF_INET_POST_ROUTING && entskb->sk == NULL)) 447 csum_verify = !skb_csum_unnecessary(entskb); 448 else 449 csum_verify = false; 450 451 outdev = entry->state.out; 452 453 switch ((enum nfqnl_config_mode)READ_ONCE(queue->copy_mode)) { 454 case NFQNL_COPY_META: 455 case NFQNL_COPY_NONE: 456 break; 457 458 case NFQNL_COPY_PACKET: 459 if (!(queue->flags & NFQA_CFG_F_GSO) && 460 entskb->ip_summed == CHECKSUM_PARTIAL && 461 skb_checksum_help(entskb)) 462 return NULL; 463 464 data_len = READ_ONCE(queue->copy_range); 465 if (data_len > entskb->len) 466 data_len = entskb->len; 467 468 hlen = skb_zerocopy_headlen(entskb); 469 hlen = min_t(unsigned int, hlen, data_len); 470 size += sizeof(struct nlattr) + hlen; 471 cap_len = entskb->len; 472 break; 473 } 474 475 nfnl_ct = rcu_dereference(nfnl_ct_hook); 476 477 #if IS_ENABLED(CONFIG_NF_CONNTRACK) 478 if (queue->flags & NFQA_CFG_F_CONNTRACK) { 479 if (nfnl_ct != NULL) { 480 ct = nf_ct_get(entskb, &ctinfo); 481 if (ct != NULL) 482 size += nfnl_ct->build_size(ct); 483 } 484 } 485 #endif 486 487 if (queue->flags & NFQA_CFG_F_UID_GID) { 488 size += (nla_total_size(sizeof(u_int32_t)) /* uid */ 489 + nla_total_size(sizeof(u_int32_t))); /* gid */ 490 } 491 492 if ((queue->flags & NFQA_CFG_F_SECCTX) && entskb->sk) { 493 seclen = nfqnl_get_sk_secctx(entskb, &secdata); 494 if (seclen) 495 size += nla_total_size(seclen); 496 } 497 498 skb = alloc_skb(size, GFP_ATOMIC); 499 if (!skb) { 500 skb_tx_error(entskb); 501 goto nlmsg_failure; 502 } 503 504 nlh = nfnl_msg_put(skb, 0, 0, 505 nfnl_msg_type(NFNL_SUBSYS_QUEUE, NFQNL_MSG_PACKET), 506 0, entry->state.pf, NFNETLINK_V0, 507 htons(queue->queue_num)); 508 if (!nlh) { 509 skb_tx_error(entskb); 510 kfree_skb(skb); 511 goto nlmsg_failure; 512 } 513 514 nla = __nla_reserve(skb, NFQA_PACKET_HDR, sizeof(*pmsg)); 515 pmsg = nla_data(nla); 516 pmsg->hw_protocol = entskb->protocol; 517 pmsg->hook = entry->state.hook; 518 *packet_id_ptr = &pmsg->packet_id; 519 520 indev = entry->state.in; 521 if (indev) { 522 #if !IS_ENABLED(CONFIG_BRIDGE_NETFILTER) 523 if (nla_put_be32(skb, NFQA_IFINDEX_INDEV, htonl(indev->ifindex))) 524 goto nla_put_failure; 525 #else 526 if (entry->state.pf == PF_BRIDGE) { 527 /* Case 1: indev is physical input device, we need to 528 * look for bridge group (when called from 529 * netfilter_bridge) */ 530 if (nla_put_be32(skb, NFQA_IFINDEX_PHYSINDEV, 531 htonl(indev->ifindex)) || 532 /* this is the bridge group "brX" */ 533 /* rcu_read_lock()ed by __nf_queue */ 534 nla_put_be32(skb, NFQA_IFINDEX_INDEV, 535 htonl(br_port_get_rcu(indev)->br->dev->ifindex))) 536 goto nla_put_failure; 537 } else { 538 int physinif; 539 540 /* Case 2: indev is bridge group, we need to look for 541 * physical device (when called from ipv4) */ 542 if (nla_put_be32(skb, NFQA_IFINDEX_INDEV, 543 htonl(indev->ifindex))) 544 goto nla_put_failure; 545 546 physinif = nf_bridge_get_physinif(entskb); 547 if (physinif && 548 nla_put_be32(skb, NFQA_IFINDEX_PHYSINDEV, 549 htonl(physinif))) 550 goto nla_put_failure; 551 } 552 #endif 553 } 554 555 if (outdev) { 556 #if !IS_ENABLED(CONFIG_BRIDGE_NETFILTER) 557 if (nla_put_be32(skb, NFQA_IFINDEX_OUTDEV, htonl(outdev->ifindex))) 558 goto nla_put_failure; 559 #else 560 if (entry->state.pf == PF_BRIDGE) { 561 /* Case 1: outdev is physical output device, we need to 562 * look for bridge group (when called from 563 * netfilter_bridge) */ 564 if (nla_put_be32(skb, NFQA_IFINDEX_PHYSOUTDEV, 565 htonl(outdev->ifindex)) || 566 /* this is the bridge group "brX" */ 567 /* rcu_read_lock()ed by __nf_queue */ 568 nla_put_be32(skb, NFQA_IFINDEX_OUTDEV, 569 htonl(br_port_get_rcu(outdev)->br->dev->ifindex))) 570 goto nla_put_failure; 571 } else { 572 int physoutif; 573 574 /* Case 2: outdev is bridge group, we need to look for 575 * physical output device (when called from ipv4) */ 576 if (nla_put_be32(skb, NFQA_IFINDEX_OUTDEV, 577 htonl(outdev->ifindex))) 578 goto nla_put_failure; 579 580 physoutif = nf_bridge_get_physoutif(entskb); 581 if (physoutif && 582 nla_put_be32(skb, NFQA_IFINDEX_PHYSOUTDEV, 583 htonl(physoutif))) 584 goto nla_put_failure; 585 } 586 #endif 587 } 588 589 if (entskb->mark && 590 nla_put_be32(skb, NFQA_MARK, htonl(entskb->mark))) 591 goto nla_put_failure; 592 593 if (entskb->priority && 594 nla_put_be32(skb, NFQA_PRIORITY, htonl(entskb->priority))) 595 goto nla_put_failure; 596 597 if (indev && entskb->dev && 598 skb_mac_header_was_set(entskb) && 599 skb_mac_header_len(entskb) != 0) { 600 struct nfqnl_msg_packet_hw phw; 601 int len; 602 603 memset(&phw, 0, sizeof(phw)); 604 len = dev_parse_header(entskb, phw.hw_addr); 605 if (len) { 606 phw.hw_addrlen = htons(len); 607 if (nla_put(skb, NFQA_HWADDR, sizeof(phw), &phw)) 608 goto nla_put_failure; 609 } 610 } 611 612 if (nfqnl_put_bridge(entry, skb) < 0) 613 goto nla_put_failure; 614 615 if (entry->state.hook <= NF_INET_FORWARD && tstamp) { 616 struct nfqnl_msg_packet_timestamp ts; 617 struct timespec64 kts = ktime_to_timespec64(tstamp); 618 619 ts.sec = cpu_to_be64(kts.tv_sec); 620 ts.usec = cpu_to_be64(kts.tv_nsec / NSEC_PER_USEC); 621 622 if (nla_put(skb, NFQA_TIMESTAMP, sizeof(ts), &ts)) 623 goto nla_put_failure; 624 } 625 626 if ((queue->flags & NFQA_CFG_F_UID_GID) && entskb->sk && 627 nfqnl_put_sk_uidgid(skb, entskb->sk) < 0) 628 goto nla_put_failure; 629 630 if (nfqnl_put_sk_classid(skb, entskb->sk) < 0) 631 goto nla_put_failure; 632 633 if (seclen && nla_put(skb, NFQA_SECCTX, seclen, secdata)) 634 goto nla_put_failure; 635 636 if (ct && nfnl_ct->build(skb, ct, ctinfo, NFQA_CT, NFQA_CT_INFO) < 0) 637 goto nla_put_failure; 638 639 if (cap_len > data_len && 640 nla_put_be32(skb, NFQA_CAP_LEN, htonl(cap_len))) 641 goto nla_put_failure; 642 643 if (nfqnl_put_packet_info(skb, entskb, csum_verify)) 644 goto nla_put_failure; 645 646 if (data_len) { 647 struct nlattr *nla; 648 649 if (skb_tailroom(skb) < sizeof(*nla) + hlen) 650 goto nla_put_failure; 651 652 nla = skb_put(skb, sizeof(*nla)); 653 nla->nla_type = NFQA_PAYLOAD; 654 nla->nla_len = nla_attr_size(data_len); 655 656 if (skb_zerocopy(skb, entskb, data_len, hlen)) 657 goto nla_put_failure; 658 } 659 660 nlh->nlmsg_len = skb->len; 661 if (seclen) 662 security_release_secctx(secdata, seclen); 663 return skb; 664 665 nla_put_failure: 666 skb_tx_error(entskb); 667 kfree_skb(skb); 668 net_err_ratelimited("nf_queue: error creating packet message\n"); 669 nlmsg_failure: 670 if (seclen) 671 security_release_secctx(secdata, seclen); 672 return NULL; 673 } 674 675 static bool nf_ct_drop_unconfirmed(const struct nf_queue_entry *entry) 676 { 677 #if IS_ENABLED(CONFIG_NF_CONNTRACK) 678 static const unsigned long flags = IPS_CONFIRMED | IPS_DYING; 679 const struct nf_conn *ct = (void *)skb_nfct(entry->skb); 680 681 if (ct && ((ct->status & flags) == IPS_DYING)) 682 return true; 683 #endif 684 return false; 685 } 686 687 static int 688 __nfqnl_enqueue_packet(struct net *net, struct nfqnl_instance *queue, 689 struct nf_queue_entry *entry) 690 { 691 struct sk_buff *nskb; 692 int err = -ENOBUFS; 693 __be32 *packet_id_ptr; 694 int failopen = 0; 695 696 nskb = nfqnl_build_packet_message(net, queue, entry, &packet_id_ptr); 697 if (nskb == NULL) { 698 err = -ENOMEM; 699 goto err_out; 700 } 701 spin_lock_bh(&queue->lock); 702 703 if (nf_ct_drop_unconfirmed(entry)) 704 goto err_out_free_nskb; 705 706 if (queue->queue_total >= queue->queue_maxlen) { 707 if (queue->flags & NFQA_CFG_F_FAIL_OPEN) { 708 failopen = 1; 709 err = 0; 710 } else { 711 queue->queue_dropped++; 712 net_warn_ratelimited("nf_queue: full at %d entries, dropping packets(s)\n", 713 queue->queue_total); 714 } 715 goto err_out_free_nskb; 716 } 717 entry->id = ++queue->id_sequence; 718 *packet_id_ptr = htonl(entry->id); 719 720 /* nfnetlink_unicast will either free the nskb or add it to a socket */ 721 err = nfnetlink_unicast(nskb, net, queue->peer_portid); 722 if (err < 0) { 723 if (queue->flags & NFQA_CFG_F_FAIL_OPEN) { 724 failopen = 1; 725 err = 0; 726 } else { 727 queue->queue_user_dropped++; 728 } 729 goto err_out_unlock; 730 } 731 732 __enqueue_entry(queue, entry); 733 734 spin_unlock_bh(&queue->lock); 735 return 0; 736 737 err_out_free_nskb: 738 kfree_skb(nskb); 739 err_out_unlock: 740 spin_unlock_bh(&queue->lock); 741 if (failopen) 742 nfqnl_reinject(entry, NF_ACCEPT); 743 err_out: 744 return err; 745 } 746 747 static struct nf_queue_entry * 748 nf_queue_entry_dup(struct nf_queue_entry *e) 749 { 750 struct nf_queue_entry *entry = kmemdup(e, e->size, GFP_ATOMIC); 751 752 if (!entry) 753 return NULL; 754 755 if (nf_queue_entry_get_refs(entry)) 756 return entry; 757 758 kfree(entry); 759 return NULL; 760 } 761 762 #if IS_ENABLED(CONFIG_BRIDGE_NETFILTER) 763 /* When called from bridge netfilter, skb->data must point to MAC header 764 * before calling skb_gso_segment(). Else, original MAC header is lost 765 * and segmented skbs will be sent to wrong destination. 766 */ 767 static void nf_bridge_adjust_skb_data(struct sk_buff *skb) 768 { 769 if (nf_bridge_info_get(skb)) 770 __skb_push(skb, skb->network_header - skb->mac_header); 771 } 772 773 static void nf_bridge_adjust_segmented_data(struct sk_buff *skb) 774 { 775 if (nf_bridge_info_get(skb)) 776 __skb_pull(skb, skb->network_header - skb->mac_header); 777 } 778 #else 779 #define nf_bridge_adjust_skb_data(s) do {} while (0) 780 #define nf_bridge_adjust_segmented_data(s) do {} while (0) 781 #endif 782 783 static int 784 __nfqnl_enqueue_packet_gso(struct net *net, struct nfqnl_instance *queue, 785 struct sk_buff *skb, struct nf_queue_entry *entry) 786 { 787 int ret = -ENOMEM; 788 struct nf_queue_entry *entry_seg; 789 790 nf_bridge_adjust_segmented_data(skb); 791 792 if (skb->next == NULL) { /* last packet, no need to copy entry */ 793 struct sk_buff *gso_skb = entry->skb; 794 entry->skb = skb; 795 ret = __nfqnl_enqueue_packet(net, queue, entry); 796 if (ret) 797 entry->skb = gso_skb; 798 return ret; 799 } 800 801 skb_mark_not_on_list(skb); 802 803 entry_seg = nf_queue_entry_dup(entry); 804 if (entry_seg) { 805 entry_seg->skb = skb; 806 ret = __nfqnl_enqueue_packet(net, queue, entry_seg); 807 if (ret) 808 nf_queue_entry_free(entry_seg); 809 } 810 return ret; 811 } 812 813 static int 814 nfqnl_enqueue_packet(struct nf_queue_entry *entry, unsigned int queuenum) 815 { 816 unsigned int queued; 817 struct nfqnl_instance *queue; 818 struct sk_buff *skb, *segs, *nskb; 819 int err = -ENOBUFS; 820 struct net *net = entry->state.net; 821 struct nfnl_queue_net *q = nfnl_queue_pernet(net); 822 823 /* rcu_read_lock()ed by nf_hook_thresh */ 824 queue = instance_lookup(q, queuenum); 825 if (!queue) 826 return -ESRCH; 827 828 if (queue->copy_mode == NFQNL_COPY_NONE) 829 return -EINVAL; 830 831 skb = entry->skb; 832 833 switch (entry->state.pf) { 834 case NFPROTO_IPV4: 835 skb->protocol = htons(ETH_P_IP); 836 break; 837 case NFPROTO_IPV6: 838 skb->protocol = htons(ETH_P_IPV6); 839 break; 840 } 841 842 if ((queue->flags & NFQA_CFG_F_GSO) || !skb_is_gso(skb)) 843 return __nfqnl_enqueue_packet(net, queue, entry); 844 845 nf_bridge_adjust_skb_data(skb); 846 segs = skb_gso_segment(skb, 0); 847 /* Does not use PTR_ERR to limit the number of error codes that can be 848 * returned by nf_queue. For instance, callers rely on -ESRCH to 849 * mean 'ignore this hook'. 850 */ 851 if (IS_ERR_OR_NULL(segs)) 852 goto out_err; 853 queued = 0; 854 err = 0; 855 skb_list_walk_safe(segs, segs, nskb) { 856 if (err == 0) 857 err = __nfqnl_enqueue_packet_gso(net, queue, 858 segs, entry); 859 if (err == 0) 860 queued++; 861 else 862 kfree_skb(segs); 863 } 864 865 if (queued) { 866 if (err) /* some segments are already queued */ 867 nf_queue_entry_free(entry); 868 kfree_skb(skb); 869 return 0; 870 } 871 out_err: 872 nf_bridge_adjust_segmented_data(skb); 873 return err; 874 } 875 876 static int 877 nfqnl_mangle(void *data, unsigned int data_len, struct nf_queue_entry *e, int diff) 878 { 879 struct sk_buff *nskb; 880 881 if (diff < 0) { 882 unsigned int min_len = skb_transport_offset(e->skb); 883 884 if (data_len < min_len) 885 return -EINVAL; 886 887 if (pskb_trim(e->skb, data_len)) 888 return -ENOMEM; 889 } else if (diff > 0) { 890 if (data_len > 0xFFFF) 891 return -EINVAL; 892 if (diff > skb_tailroom(e->skb)) { 893 nskb = skb_copy_expand(e->skb, skb_headroom(e->skb), 894 diff, GFP_ATOMIC); 895 if (!nskb) 896 return -ENOMEM; 897 kfree_skb(e->skb); 898 e->skb = nskb; 899 } 900 skb_put(e->skb, diff); 901 } 902 if (skb_ensure_writable(e->skb, data_len)) 903 return -ENOMEM; 904 skb_copy_to_linear_data(e->skb, data, data_len); 905 e->skb->ip_summed = CHECKSUM_NONE; 906 return 0; 907 } 908 909 static int 910 nfqnl_set_mode(struct nfqnl_instance *queue, 911 unsigned char mode, unsigned int range) 912 { 913 int status = 0; 914 915 spin_lock_bh(&queue->lock); 916 switch (mode) { 917 case NFQNL_COPY_NONE: 918 case NFQNL_COPY_META: 919 queue->copy_mode = mode; 920 queue->copy_range = 0; 921 break; 922 923 case NFQNL_COPY_PACKET: 924 queue->copy_mode = mode; 925 if (range == 0 || range > NFQNL_MAX_COPY_RANGE) 926 queue->copy_range = NFQNL_MAX_COPY_RANGE; 927 else 928 queue->copy_range = range; 929 break; 930 931 default: 932 status = -EINVAL; 933 934 } 935 spin_unlock_bh(&queue->lock); 936 937 return status; 938 } 939 940 static int 941 dev_cmp(struct nf_queue_entry *entry, unsigned long ifindex) 942 { 943 #if IS_ENABLED(CONFIG_BRIDGE_NETFILTER) 944 int physinif, physoutif; 945 946 physinif = nf_bridge_get_physinif(entry->skb); 947 physoutif = nf_bridge_get_physoutif(entry->skb); 948 949 if (physinif == ifindex || physoutif == ifindex) 950 return 1; 951 #endif 952 if (entry->state.in) 953 if (entry->state.in->ifindex == ifindex) 954 return 1; 955 if (entry->state.out) 956 if (entry->state.out->ifindex == ifindex) 957 return 1; 958 959 return 0; 960 } 961 962 /* drop all packets with either indev or outdev == ifindex from all queue 963 * instances */ 964 static void 965 nfqnl_dev_drop(struct net *net, int ifindex) 966 { 967 int i; 968 struct nfnl_queue_net *q = nfnl_queue_pernet(net); 969 970 rcu_read_lock(); 971 972 for (i = 0; i < INSTANCE_BUCKETS; i++) { 973 struct nfqnl_instance *inst; 974 struct hlist_head *head = &q->instance_table[i]; 975 976 hlist_for_each_entry_rcu(inst, head, hlist) 977 nfqnl_flush(inst, dev_cmp, ifindex); 978 } 979 980 rcu_read_unlock(); 981 } 982 983 static int 984 nfqnl_rcv_dev_event(struct notifier_block *this, 985 unsigned long event, void *ptr) 986 { 987 struct net_device *dev = netdev_notifier_info_to_dev(ptr); 988 989 /* Drop any packets associated with the downed device */ 990 if (event == NETDEV_DOWN) 991 nfqnl_dev_drop(dev_net(dev), dev->ifindex); 992 return NOTIFY_DONE; 993 } 994 995 static struct notifier_block nfqnl_dev_notifier = { 996 .notifier_call = nfqnl_rcv_dev_event, 997 }; 998 999 static void nfqnl_nf_hook_drop(struct net *net) 1000 { 1001 struct nfnl_queue_net *q = nfnl_queue_pernet(net); 1002 int i; 1003 1004 /* This function is also called on net namespace error unwind, 1005 * when pernet_ops->init() failed and ->exit() functions of the 1006 * previous pernet_ops gets called. 1007 * 1008 * This may result in a call to nfqnl_nf_hook_drop() before 1009 * struct nfnl_queue_net was allocated. 1010 */ 1011 if (!q) 1012 return; 1013 1014 for (i = 0; i < INSTANCE_BUCKETS; i++) { 1015 struct nfqnl_instance *inst; 1016 struct hlist_head *head = &q->instance_table[i]; 1017 1018 hlist_for_each_entry_rcu(inst, head, hlist) 1019 nfqnl_flush(inst, NULL, 0); 1020 } 1021 } 1022 1023 static int 1024 nfqnl_rcv_nl_event(struct notifier_block *this, 1025 unsigned long event, void *ptr) 1026 { 1027 struct netlink_notify *n = ptr; 1028 struct nfnl_queue_net *q = nfnl_queue_pernet(n->net); 1029 1030 if (event == NETLINK_URELEASE && n->protocol == NETLINK_NETFILTER) { 1031 int i; 1032 1033 /* destroy all instances for this portid */ 1034 spin_lock(&q->instances_lock); 1035 for (i = 0; i < INSTANCE_BUCKETS; i++) { 1036 struct hlist_node *t2; 1037 struct nfqnl_instance *inst; 1038 struct hlist_head *head = &q->instance_table[i]; 1039 1040 hlist_for_each_entry_safe(inst, t2, head, hlist) { 1041 if (n->portid == inst->peer_portid) 1042 __instance_destroy(inst); 1043 } 1044 } 1045 spin_unlock(&q->instances_lock); 1046 } 1047 return NOTIFY_DONE; 1048 } 1049 1050 static struct notifier_block nfqnl_rtnl_notifier = { 1051 .notifier_call = nfqnl_rcv_nl_event, 1052 }; 1053 1054 static const struct nla_policy nfqa_vlan_policy[NFQA_VLAN_MAX + 1] = { 1055 [NFQA_VLAN_TCI] = { .type = NLA_U16}, 1056 [NFQA_VLAN_PROTO] = { .type = NLA_U16}, 1057 }; 1058 1059 static const struct nla_policy nfqa_verdict_policy[NFQA_MAX+1] = { 1060 [NFQA_VERDICT_HDR] = { .len = sizeof(struct nfqnl_msg_verdict_hdr) }, 1061 [NFQA_MARK] = { .type = NLA_U32 }, 1062 [NFQA_PAYLOAD] = { .type = NLA_UNSPEC }, 1063 [NFQA_CT] = { .type = NLA_UNSPEC }, 1064 [NFQA_EXP] = { .type = NLA_UNSPEC }, 1065 [NFQA_VLAN] = { .type = NLA_NESTED }, 1066 [NFQA_PRIORITY] = { .type = NLA_U32 }, 1067 }; 1068 1069 static const struct nla_policy nfqa_verdict_batch_policy[NFQA_MAX+1] = { 1070 [NFQA_VERDICT_HDR] = { .len = sizeof(struct nfqnl_msg_verdict_hdr) }, 1071 [NFQA_MARK] = { .type = NLA_U32 }, 1072 [NFQA_PRIORITY] = { .type = NLA_U32 }, 1073 }; 1074 1075 static struct nfqnl_instance * 1076 verdict_instance_lookup(struct nfnl_queue_net *q, u16 queue_num, u32 nlportid) 1077 { 1078 struct nfqnl_instance *queue; 1079 1080 queue = instance_lookup(q, queue_num); 1081 if (!queue) 1082 return ERR_PTR(-ENODEV); 1083 1084 if (queue->peer_portid != nlportid) 1085 return ERR_PTR(-EPERM); 1086 1087 return queue; 1088 } 1089 1090 static struct nfqnl_msg_verdict_hdr* 1091 verdicthdr_get(const struct nlattr * const nfqa[]) 1092 { 1093 struct nfqnl_msg_verdict_hdr *vhdr; 1094 unsigned int verdict; 1095 1096 if (!nfqa[NFQA_VERDICT_HDR]) 1097 return NULL; 1098 1099 vhdr = nla_data(nfqa[NFQA_VERDICT_HDR]); 1100 verdict = ntohl(vhdr->verdict) & NF_VERDICT_MASK; 1101 if (verdict > NF_MAX_VERDICT || verdict == NF_STOLEN) 1102 return NULL; 1103 return vhdr; 1104 } 1105 1106 static int nfq_id_after(unsigned int id, unsigned int max) 1107 { 1108 return (int)(id - max) > 0; 1109 } 1110 1111 static int nfqnl_recv_verdict_batch(struct sk_buff *skb, 1112 const struct nfnl_info *info, 1113 const struct nlattr * const nfqa[]) 1114 { 1115 struct nfnl_queue_net *q = nfnl_queue_pernet(info->net); 1116 u16 queue_num = ntohs(info->nfmsg->res_id); 1117 struct nf_queue_entry *entry, *tmp; 1118 struct nfqnl_msg_verdict_hdr *vhdr; 1119 struct nfqnl_instance *queue; 1120 unsigned int verdict, maxid; 1121 LIST_HEAD(batch_list); 1122 1123 queue = verdict_instance_lookup(q, queue_num, 1124 NETLINK_CB(skb).portid); 1125 if (IS_ERR(queue)) 1126 return PTR_ERR(queue); 1127 1128 vhdr = verdicthdr_get(nfqa); 1129 if (!vhdr) 1130 return -EINVAL; 1131 1132 verdict = ntohl(vhdr->verdict); 1133 maxid = ntohl(vhdr->id); 1134 1135 spin_lock_bh(&queue->lock); 1136 1137 list_for_each_entry_safe(entry, tmp, &queue->queue_list, list) { 1138 if (nfq_id_after(entry->id, maxid)) 1139 break; 1140 __dequeue_entry(queue, entry); 1141 list_add_tail(&entry->list, &batch_list); 1142 } 1143 1144 spin_unlock_bh(&queue->lock); 1145 1146 if (list_empty(&batch_list)) 1147 return -ENOENT; 1148 1149 list_for_each_entry_safe(entry, tmp, &batch_list, list) { 1150 if (nfqa[NFQA_MARK]) 1151 entry->skb->mark = ntohl(nla_get_be32(nfqa[NFQA_MARK])); 1152 1153 if (nfqa[NFQA_PRIORITY]) 1154 entry->skb->priority = ntohl(nla_get_be32(nfqa[NFQA_PRIORITY])); 1155 1156 nfqnl_reinject(entry, verdict); 1157 } 1158 return 0; 1159 } 1160 1161 static struct nf_conn *nfqnl_ct_parse(const struct nfnl_ct_hook *nfnl_ct, 1162 const struct nlmsghdr *nlh, 1163 const struct nlattr * const nfqa[], 1164 struct nf_queue_entry *entry, 1165 enum ip_conntrack_info *ctinfo) 1166 { 1167 #if IS_ENABLED(CONFIG_NF_CONNTRACK) 1168 struct nf_conn *ct; 1169 1170 ct = nf_ct_get(entry->skb, ctinfo); 1171 if (ct == NULL) 1172 return NULL; 1173 1174 if (nfnl_ct->parse(nfqa[NFQA_CT], ct) < 0) 1175 return NULL; 1176 1177 if (nfqa[NFQA_EXP]) 1178 nfnl_ct->attach_expect(nfqa[NFQA_EXP], ct, 1179 NETLINK_CB(entry->skb).portid, 1180 nlmsg_report(nlh)); 1181 return ct; 1182 #else 1183 return NULL; 1184 #endif 1185 } 1186 1187 static int nfqa_parse_bridge(struct nf_queue_entry *entry, 1188 const struct nlattr * const nfqa[]) 1189 { 1190 if (nfqa[NFQA_VLAN]) { 1191 struct nlattr *tb[NFQA_VLAN_MAX + 1]; 1192 int err; 1193 1194 err = nla_parse_nested_deprecated(tb, NFQA_VLAN_MAX, 1195 nfqa[NFQA_VLAN], 1196 nfqa_vlan_policy, NULL); 1197 if (err < 0) 1198 return err; 1199 1200 if (!tb[NFQA_VLAN_TCI] || !tb[NFQA_VLAN_PROTO]) 1201 return -EINVAL; 1202 1203 __vlan_hwaccel_put_tag(entry->skb, 1204 nla_get_be16(tb[NFQA_VLAN_PROTO]), 1205 ntohs(nla_get_be16(tb[NFQA_VLAN_TCI]))); 1206 } 1207 1208 if (nfqa[NFQA_L2HDR]) { 1209 int mac_header_len = entry->skb->network_header - 1210 entry->skb->mac_header; 1211 1212 if (mac_header_len != nla_len(nfqa[NFQA_L2HDR])) 1213 return -EINVAL; 1214 else if (mac_header_len > 0) 1215 memcpy(skb_mac_header(entry->skb), 1216 nla_data(nfqa[NFQA_L2HDR]), 1217 mac_header_len); 1218 } 1219 1220 return 0; 1221 } 1222 1223 static int nfqnl_recv_verdict(struct sk_buff *skb, const struct nfnl_info *info, 1224 const struct nlattr * const nfqa[]) 1225 { 1226 struct nfnl_queue_net *q = nfnl_queue_pernet(info->net); 1227 u_int16_t queue_num = ntohs(info->nfmsg->res_id); 1228 const struct nfnl_ct_hook *nfnl_ct; 1229 struct nfqnl_msg_verdict_hdr *vhdr; 1230 enum ip_conntrack_info ctinfo; 1231 struct nfqnl_instance *queue; 1232 struct nf_queue_entry *entry; 1233 struct nf_conn *ct = NULL; 1234 unsigned int verdict; 1235 int err; 1236 1237 queue = verdict_instance_lookup(q, queue_num, 1238 NETLINK_CB(skb).portid); 1239 if (IS_ERR(queue)) 1240 return PTR_ERR(queue); 1241 1242 vhdr = verdicthdr_get(nfqa); 1243 if (!vhdr) 1244 return -EINVAL; 1245 1246 verdict = ntohl(vhdr->verdict); 1247 1248 entry = find_dequeue_entry(queue, ntohl(vhdr->id)); 1249 if (entry == NULL) 1250 return -ENOENT; 1251 1252 /* rcu lock already held from nfnl->call_rcu. */ 1253 nfnl_ct = rcu_dereference(nfnl_ct_hook); 1254 1255 if (nfqa[NFQA_CT]) { 1256 if (nfnl_ct != NULL) 1257 ct = nfqnl_ct_parse(nfnl_ct, info->nlh, nfqa, entry, 1258 &ctinfo); 1259 } 1260 1261 if (entry->state.pf == PF_BRIDGE) { 1262 err = nfqa_parse_bridge(entry, nfqa); 1263 if (err < 0) 1264 return err; 1265 } 1266 1267 if (nfqa[NFQA_PAYLOAD]) { 1268 u16 payload_len = nla_len(nfqa[NFQA_PAYLOAD]); 1269 int diff = payload_len - entry->skb->len; 1270 1271 if (nfqnl_mangle(nla_data(nfqa[NFQA_PAYLOAD]), 1272 payload_len, entry, diff) < 0) 1273 verdict = NF_DROP; 1274 1275 if (ct && diff) 1276 nfnl_ct->seq_adjust(entry->skb, ct, ctinfo, diff); 1277 } 1278 1279 if (nfqa[NFQA_MARK]) 1280 entry->skb->mark = ntohl(nla_get_be32(nfqa[NFQA_MARK])); 1281 1282 if (nfqa[NFQA_PRIORITY]) 1283 entry->skb->priority = ntohl(nla_get_be32(nfqa[NFQA_PRIORITY])); 1284 1285 nfqnl_reinject(entry, verdict); 1286 return 0; 1287 } 1288 1289 static int nfqnl_recv_unsupp(struct sk_buff *skb, const struct nfnl_info *info, 1290 const struct nlattr * const cda[]) 1291 { 1292 return -ENOTSUPP; 1293 } 1294 1295 static const struct nla_policy nfqa_cfg_policy[NFQA_CFG_MAX+1] = { 1296 [NFQA_CFG_CMD] = { .len = sizeof(struct nfqnl_msg_config_cmd) }, 1297 [NFQA_CFG_PARAMS] = { .len = sizeof(struct nfqnl_msg_config_params) }, 1298 [NFQA_CFG_QUEUE_MAXLEN] = { .type = NLA_U32 }, 1299 [NFQA_CFG_MASK] = { .type = NLA_U32 }, 1300 [NFQA_CFG_FLAGS] = { .type = NLA_U32 }, 1301 }; 1302 1303 static const struct nf_queue_handler nfqh = { 1304 .outfn = nfqnl_enqueue_packet, 1305 .nf_hook_drop = nfqnl_nf_hook_drop, 1306 }; 1307 1308 static int nfqnl_recv_config(struct sk_buff *skb, const struct nfnl_info *info, 1309 const struct nlattr * const nfqa[]) 1310 { 1311 struct nfnl_queue_net *q = nfnl_queue_pernet(info->net); 1312 u_int16_t queue_num = ntohs(info->nfmsg->res_id); 1313 struct nfqnl_msg_config_cmd *cmd = NULL; 1314 struct nfqnl_instance *queue; 1315 __u32 flags = 0, mask = 0; 1316 int ret = 0; 1317 1318 if (nfqa[NFQA_CFG_CMD]) { 1319 cmd = nla_data(nfqa[NFQA_CFG_CMD]); 1320 1321 /* Obsolete commands without queue context */ 1322 switch (cmd->command) { 1323 case NFQNL_CFG_CMD_PF_BIND: return 0; 1324 case NFQNL_CFG_CMD_PF_UNBIND: return 0; 1325 } 1326 } 1327 1328 /* Check if we support these flags in first place, dependencies should 1329 * be there too not to break atomicity. 1330 */ 1331 if (nfqa[NFQA_CFG_FLAGS]) { 1332 if (!nfqa[NFQA_CFG_MASK]) { 1333 /* A mask is needed to specify which flags are being 1334 * changed. 1335 */ 1336 return -EINVAL; 1337 } 1338 1339 flags = ntohl(nla_get_be32(nfqa[NFQA_CFG_FLAGS])); 1340 mask = ntohl(nla_get_be32(nfqa[NFQA_CFG_MASK])); 1341 1342 if (flags >= NFQA_CFG_F_MAX) 1343 return -EOPNOTSUPP; 1344 1345 #if !IS_ENABLED(CONFIG_NETWORK_SECMARK) 1346 if (flags & mask & NFQA_CFG_F_SECCTX) 1347 return -EOPNOTSUPP; 1348 #endif 1349 if ((flags & mask & NFQA_CFG_F_CONNTRACK) && 1350 !rcu_access_pointer(nfnl_ct_hook)) { 1351 #ifdef CONFIG_MODULES 1352 nfnl_unlock(NFNL_SUBSYS_QUEUE); 1353 request_module("ip_conntrack_netlink"); 1354 nfnl_lock(NFNL_SUBSYS_QUEUE); 1355 if (rcu_access_pointer(nfnl_ct_hook)) 1356 return -EAGAIN; 1357 #endif 1358 return -EOPNOTSUPP; 1359 } 1360 } 1361 1362 rcu_read_lock(); 1363 queue = instance_lookup(q, queue_num); 1364 if (queue && queue->peer_portid != NETLINK_CB(skb).portid) { 1365 ret = -EPERM; 1366 goto err_out_unlock; 1367 } 1368 1369 if (cmd != NULL) { 1370 switch (cmd->command) { 1371 case NFQNL_CFG_CMD_BIND: 1372 if (queue) { 1373 ret = -EBUSY; 1374 goto err_out_unlock; 1375 } 1376 queue = instance_create(q, queue_num, 1377 NETLINK_CB(skb).portid); 1378 if (IS_ERR(queue)) { 1379 ret = PTR_ERR(queue); 1380 goto err_out_unlock; 1381 } 1382 break; 1383 case NFQNL_CFG_CMD_UNBIND: 1384 if (!queue) { 1385 ret = -ENODEV; 1386 goto err_out_unlock; 1387 } 1388 instance_destroy(q, queue); 1389 goto err_out_unlock; 1390 case NFQNL_CFG_CMD_PF_BIND: 1391 case NFQNL_CFG_CMD_PF_UNBIND: 1392 break; 1393 default: 1394 ret = -ENOTSUPP; 1395 goto err_out_unlock; 1396 } 1397 } 1398 1399 if (!queue) { 1400 ret = -ENODEV; 1401 goto err_out_unlock; 1402 } 1403 1404 if (nfqa[NFQA_CFG_PARAMS]) { 1405 struct nfqnl_msg_config_params *params = 1406 nla_data(nfqa[NFQA_CFG_PARAMS]); 1407 1408 nfqnl_set_mode(queue, params->copy_mode, 1409 ntohl(params->copy_range)); 1410 } 1411 1412 if (nfqa[NFQA_CFG_QUEUE_MAXLEN]) { 1413 __be32 *queue_maxlen = nla_data(nfqa[NFQA_CFG_QUEUE_MAXLEN]); 1414 1415 spin_lock_bh(&queue->lock); 1416 queue->queue_maxlen = ntohl(*queue_maxlen); 1417 spin_unlock_bh(&queue->lock); 1418 } 1419 1420 if (nfqa[NFQA_CFG_FLAGS]) { 1421 spin_lock_bh(&queue->lock); 1422 queue->flags &= ~mask; 1423 queue->flags |= flags & mask; 1424 spin_unlock_bh(&queue->lock); 1425 } 1426 1427 err_out_unlock: 1428 rcu_read_unlock(); 1429 return ret; 1430 } 1431 1432 static const struct nfnl_callback nfqnl_cb[NFQNL_MSG_MAX] = { 1433 [NFQNL_MSG_PACKET] = { 1434 .call = nfqnl_recv_unsupp, 1435 .type = NFNL_CB_RCU, 1436 .attr_count = NFQA_MAX, 1437 }, 1438 [NFQNL_MSG_VERDICT] = { 1439 .call = nfqnl_recv_verdict, 1440 .type = NFNL_CB_RCU, 1441 .attr_count = NFQA_MAX, 1442 .policy = nfqa_verdict_policy 1443 }, 1444 [NFQNL_MSG_CONFIG] = { 1445 .call = nfqnl_recv_config, 1446 .type = NFNL_CB_MUTEX, 1447 .attr_count = NFQA_CFG_MAX, 1448 .policy = nfqa_cfg_policy 1449 }, 1450 [NFQNL_MSG_VERDICT_BATCH] = { 1451 .call = nfqnl_recv_verdict_batch, 1452 .type = NFNL_CB_RCU, 1453 .attr_count = NFQA_MAX, 1454 .policy = nfqa_verdict_batch_policy 1455 }, 1456 }; 1457 1458 static const struct nfnetlink_subsystem nfqnl_subsys = { 1459 .name = "nf_queue", 1460 .subsys_id = NFNL_SUBSYS_QUEUE, 1461 .cb_count = NFQNL_MSG_MAX, 1462 .cb = nfqnl_cb, 1463 }; 1464 1465 #ifdef CONFIG_PROC_FS 1466 struct iter_state { 1467 struct seq_net_private p; 1468 unsigned int bucket; 1469 }; 1470 1471 static struct hlist_node *get_first(struct seq_file *seq) 1472 { 1473 struct iter_state *st = seq->private; 1474 struct net *net; 1475 struct nfnl_queue_net *q; 1476 1477 if (!st) 1478 return NULL; 1479 1480 net = seq_file_net(seq); 1481 q = nfnl_queue_pernet(net); 1482 for (st->bucket = 0; st->bucket < INSTANCE_BUCKETS; st->bucket++) { 1483 if (!hlist_empty(&q->instance_table[st->bucket])) 1484 return q->instance_table[st->bucket].first; 1485 } 1486 return NULL; 1487 } 1488 1489 static struct hlist_node *get_next(struct seq_file *seq, struct hlist_node *h) 1490 { 1491 struct iter_state *st = seq->private; 1492 struct net *net = seq_file_net(seq); 1493 1494 h = h->next; 1495 while (!h) { 1496 struct nfnl_queue_net *q; 1497 1498 if (++st->bucket >= INSTANCE_BUCKETS) 1499 return NULL; 1500 1501 q = nfnl_queue_pernet(net); 1502 h = q->instance_table[st->bucket].first; 1503 } 1504 return h; 1505 } 1506 1507 static struct hlist_node *get_idx(struct seq_file *seq, loff_t pos) 1508 { 1509 struct hlist_node *head; 1510 head = get_first(seq); 1511 1512 if (head) 1513 while (pos && (head = get_next(seq, head))) 1514 pos--; 1515 return pos ? NULL : head; 1516 } 1517 1518 static void *seq_start(struct seq_file *s, loff_t *pos) 1519 __acquires(nfnl_queue_pernet(seq_file_net(s))->instances_lock) 1520 { 1521 spin_lock(&nfnl_queue_pernet(seq_file_net(s))->instances_lock); 1522 return get_idx(s, *pos); 1523 } 1524 1525 static void *seq_next(struct seq_file *s, void *v, loff_t *pos) 1526 { 1527 (*pos)++; 1528 return get_next(s, v); 1529 } 1530 1531 static void seq_stop(struct seq_file *s, void *v) 1532 __releases(nfnl_queue_pernet(seq_file_net(s))->instances_lock) 1533 { 1534 spin_unlock(&nfnl_queue_pernet(seq_file_net(s))->instances_lock); 1535 } 1536 1537 static int seq_show(struct seq_file *s, void *v) 1538 { 1539 const struct nfqnl_instance *inst = v; 1540 1541 seq_printf(s, "%5u %6u %5u %1u %5u %5u %5u %8u %2d\n", 1542 inst->queue_num, 1543 inst->peer_portid, inst->queue_total, 1544 inst->copy_mode, inst->copy_range, 1545 inst->queue_dropped, inst->queue_user_dropped, 1546 inst->id_sequence, 1); 1547 return 0; 1548 } 1549 1550 static const struct seq_operations nfqnl_seq_ops = { 1551 .start = seq_start, 1552 .next = seq_next, 1553 .stop = seq_stop, 1554 .show = seq_show, 1555 }; 1556 #endif /* PROC_FS */ 1557 1558 static int __net_init nfnl_queue_net_init(struct net *net) 1559 { 1560 unsigned int i; 1561 struct nfnl_queue_net *q = nfnl_queue_pernet(net); 1562 1563 for (i = 0; i < INSTANCE_BUCKETS; i++) 1564 INIT_HLIST_HEAD(&q->instance_table[i]); 1565 1566 spin_lock_init(&q->instances_lock); 1567 1568 #ifdef CONFIG_PROC_FS 1569 if (!proc_create_net("nfnetlink_queue", 0440, net->nf.proc_netfilter, 1570 &nfqnl_seq_ops, sizeof(struct iter_state))) 1571 return -ENOMEM; 1572 #endif 1573 return 0; 1574 } 1575 1576 static void __net_exit nfnl_queue_net_exit(struct net *net) 1577 { 1578 struct nfnl_queue_net *q = nfnl_queue_pernet(net); 1579 unsigned int i; 1580 1581 #ifdef CONFIG_PROC_FS 1582 remove_proc_entry("nfnetlink_queue", net->nf.proc_netfilter); 1583 #endif 1584 for (i = 0; i < INSTANCE_BUCKETS; i++) 1585 WARN_ON_ONCE(!hlist_empty(&q->instance_table[i])); 1586 } 1587 1588 static struct pernet_operations nfnl_queue_net_ops = { 1589 .init = nfnl_queue_net_init, 1590 .exit = nfnl_queue_net_exit, 1591 .id = &nfnl_queue_net_id, 1592 .size = sizeof(struct nfnl_queue_net), 1593 }; 1594 1595 static int __init nfnetlink_queue_init(void) 1596 { 1597 int status; 1598 1599 status = register_pernet_subsys(&nfnl_queue_net_ops); 1600 if (status < 0) { 1601 pr_err("failed to register pernet ops\n"); 1602 goto out; 1603 } 1604 1605 netlink_register_notifier(&nfqnl_rtnl_notifier); 1606 status = nfnetlink_subsys_register(&nfqnl_subsys); 1607 if (status < 0) { 1608 pr_err("failed to create netlink socket\n"); 1609 goto cleanup_netlink_notifier; 1610 } 1611 1612 status = register_netdevice_notifier(&nfqnl_dev_notifier); 1613 if (status < 0) { 1614 pr_err("failed to register netdevice notifier\n"); 1615 goto cleanup_netlink_subsys; 1616 } 1617 1618 nf_register_queue_handler(&nfqh); 1619 1620 return status; 1621 1622 cleanup_netlink_subsys: 1623 nfnetlink_subsys_unregister(&nfqnl_subsys); 1624 cleanup_netlink_notifier: 1625 netlink_unregister_notifier(&nfqnl_rtnl_notifier); 1626 unregister_pernet_subsys(&nfnl_queue_net_ops); 1627 out: 1628 return status; 1629 } 1630 1631 static void __exit nfnetlink_queue_fini(void) 1632 { 1633 nf_unregister_queue_handler(); 1634 unregister_netdevice_notifier(&nfqnl_dev_notifier); 1635 nfnetlink_subsys_unregister(&nfqnl_subsys); 1636 netlink_unregister_notifier(&nfqnl_rtnl_notifier); 1637 unregister_pernet_subsys(&nfnl_queue_net_ops); 1638 1639 rcu_barrier(); /* Wait for completion of call_rcu()'s */ 1640 } 1641 1642 MODULE_DESCRIPTION("netfilter packet queue handler"); 1643 MODULE_AUTHOR("Harald Welte <[email protected]>"); 1644 MODULE_LICENSE("GPL"); 1645 MODULE_ALIAS_NFNL_SUBSYS(NFNL_SUBSYS_QUEUE); 1646 1647 module_init(nfnetlink_queue_init); 1648 module_exit(nfnetlink_queue_fini); 1649