net/netfilter/nfnetlink_queue.c

   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 <laforge@netfilter.org>
   6  * (C) 2007 by Patrick McHardy <kaber@trash.net>
   7  *
   8  * Based on the old ipv4-only ip_queue.c:
   9  * (C) 2000-2002 James Morris <jmorris@intercode.com.au>
  10  * (C) 2003-2005 Netfilter Core Team <coreteam@netfilter.org>
  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/slab.h>
  22 #include <linux/notifier.h>
  23 #include <linux/netdevice.h>
  24 #include <linux/netfilter.h>
  25 #include <linux/proc_fs.h>
  26 #include <linux/netfilter_ipv4.h>
  27 #include <linux/netfilter_ipv6.h>
  28 #include <linux/netfilter_bridge.h>
  29 #include <linux/netfilter/nfnetlink.h>
  30 #include <linux/netfilter/nfnetlink_queue.h>
  31 #include <linux/netfilter/nf_conntrack_common.h>
  32 #include <linux/list.h>
  33 #include <net/sock.h>
  34 #include <net/tcp_states.h>
  35 #include <net/netfilter/nf_queue.h>
  36 #include <net/netns/generic.h>
  37
  38 #include <linux/atomic.h>
  39
  40 #if IS_ENABLED(CONFIG_BRIDGE_NETFILTER)
  41 #include "../bridge/br_private.h"
  42 #endif
  43
  44 #define NFQNL_QMAX_DEFAULT 1024
  45
  46 /* We're using struct nlattr which has 16bit nla_len. Note that nla_len
  47  * includes the header length. Thus, the maximum packet length that we
  48  * support is 65531 bytes. We send truncated packets if the specified length
  49  * is larger than that.  Userspace can check for presence of NFQA_CAP_LEN
  50  * attribute to detect truncation.
  51  */
  52 #define NFQNL_MAX_COPY_RANGE (0xffff - NLA_HDRLEN)
  53
  54 struct nfqnl_instance {
  55         struct hlist_node hlist;                /* global list of queues */
  56         struct rcu_head rcu;
  57
  58         u32 peer_portid;
  59         unsigned int queue_maxlen;
  60         unsigned int copy_range;
  61         unsigned int queue_dropped;
  62         unsigned int queue_user_dropped;
  63
  64
  65         u_int16_t queue_num;                    /* number of this queue */
  66         u_int8_t copy_mode;
  67         u_int32_t flags;                        /* Set using NFQA_CFG_FLAGS */
  68 /*
  69  * Following fields are dirtied for each queued packet,
  70  * keep them in same cache line if possible.
  71  */
  72         spinlock_t      lock;
  73         unsigned int    queue_total;
  74         unsigned int    id_sequence;            /* 'sequence' of pkt ids */
  75         struct list_head queue_list;            /* packets in queue */
  76 };
  77
  78 typedef int (*nfqnl_cmpfn)(struct nf_queue_entry *, unsigned long);
  79
  80 static int nfnl_queue_net_id __read_mostly;
  81
  82 #define INSTANCE_BUCKETS        16
  83 struct nfnl_queue_net {
  84         spinlock_t instances_lock;
  85         struct hlist_head instance_table[INSTANCE_BUCKETS];
  86 };
  87
  88 static struct nfnl_queue_net *nfnl_queue_pernet(struct net *net)
  89 {
  90         return net_generic(net, nfnl_queue_net_id);
  91 }
  92
  93 static inline u_int8_t instance_hashfn(u_int16_t queue_num)
  94 {
  95         return ((queue_num >> 8) ^ queue_num) % INSTANCE_BUCKETS;
  96 }
  97
  98 static struct nfqnl_instance *
  99 instance_lookup(struct nfnl_queue_net *q, u_int16_t queue_num)
 100 {
 101         struct hlist_head *head;
 102         struct nfqnl_instance *inst;
 103
 104         head = &q->instance_table[instance_hashfn(queue_num)];
 105         hlist_for_each_entry_rcu(inst, head, hlist) {
 106                 if (inst->queue_num == queue_num)
 107                         return inst;
 108         }
 109         return NULL;
 110 }
 111
 112 static struct nfqnl_instance *
 113 instance_create(struct nfnl_queue_net *q, u_int16_t queue_num, u32 portid)
 114 {
 115         struct nfqnl_instance *inst;
 116         unsigned int h;
 117         int err;
 118
 119         spin_lock(&q->instances_lock);
 120         if (instance_lookup(q, queue_num)) {
 121                 err = -EEXIST;
 122                 goto out_unlock;
 123         }
 124
 125         inst = kzalloc(sizeof(*inst), GFP_ATOMIC);
 126         if (!inst) {
 127                 err = -ENOMEM;
 128                 goto out_unlock;
 129         }
 130
 131         inst->queue_num = queue_num;
 132         inst->peer_portid = portid;
 133         inst->queue_maxlen = NFQNL_QMAX_DEFAULT;
 134         inst->copy_range = NFQNL_MAX_COPY_RANGE;
 135         inst->copy_mode = NFQNL_COPY_NONE;
 136         spin_lock_init(&inst->lock);
 137         INIT_LIST_HEAD(&inst->queue_list);
 138
 139         if (!try_module_get(THIS_MODULE)) {
 140                 err = -EAGAIN;
 141                 goto out_free;
 142         }
 143
 144         h = instance_hashfn(queue_num);
 145         hlist_add_head_rcu(&inst->hlist, &q->instance_table[h]);
 146
 147         spin_unlock(&q->instances_lock);
 148
 149         return inst;
 150
 151 out_free:
 152         kfree(inst);
 153 out_unlock:
 154         spin_unlock(&q->instances_lock);
 155         return ERR_PTR(err);
 156 }
 157
 158 static void nfqnl_flush(struct nfqnl_instance *queue, nfqnl_cmpfn cmpfn,
 159                         unsigned long data);
 160
 161 static void
 162 instance_destroy_rcu(struct rcu_head *head)
 163 {
 164         struct nfqnl_instance *inst = container_of(head, struct nfqnl_instance,
 165                                                    rcu);
 166
 167         nfqnl_flush(inst, NULL, 0);
 168         kfree(inst);
 169         module_put(THIS_MODULE);
 170 }
 171
 172 static void
 173 __instance_destroy(struct nfqnl_instance *inst)
 174 {
 175         hlist_del_rcu(&inst->hlist);
 176         call_rcu(&inst->rcu, instance_destroy_rcu);
 177 }
 178
 179 static void
 180 instance_destroy(struct nfnl_queue_net *q, struct nfqnl_instance *inst)
 181 {
 182         spin_lock(&q->instances_lock);
 183         __instance_destroy(inst);
 184         spin_unlock(&q->instances_lock);
 185 }
 186
 187 static inline void
 188 __enqueue_entry(struct nfqnl_instance *queue, struct nf_queue_entry *entry)
 189 {
 190        list_add_tail(&entry->list, &queue->queue_list);
 191        queue->queue_total++;
 192 }
 193
 194 static void
 195 __dequeue_entry(struct nfqnl_instance *queue, struct nf_queue_entry *entry)
 196 {
 197         list_del(&entry->list);
 198         queue->queue_total--;
 199 }
 200
 201 static struct nf_queue_entry *
 202 find_dequeue_entry(struct nfqnl_instance *queue, unsigned int id)
 203 {
 204         struct nf_queue_entry *entry = NULL, *i;
 205
 206         spin_lock_bh(&queue->lock);
 207
 208         list_for_each_entry(i, &queue->queue_list, list) {
 209                 if (i->id == id) {
 210                         entry = i;
 211                         break;
 212                 }
 213         }
 214
 215         if (entry)
 216                 __dequeue_entry(queue, entry);
 217
 218         spin_unlock_bh(&queue->lock);
 219
 220         return entry;
 221 }
 222
 223 static void
 224 nfqnl_flush(struct nfqnl_instance *queue, nfqnl_cmpfn cmpfn, unsigned long data)
 225 {
 226         struct nf_queue_entry *entry, *next;
 227
 228         spin_lock_bh(&queue->lock);
 229         list_for_each_entry_safe(entry, next, &queue->queue_list, list) {
 230                 if (!cmpfn || cmpfn(entry, data)) {
 231                         list_del(&entry->list);
 232                         queue->queue_total--;
 233                         nf_reinject(entry, NF_DROP);
 234                 }
 235         }
 236         spin_unlock_bh(&queue->lock);
 237 }
 238
 239 static int
 240 nfqnl_put_packet_info(struct sk_buff *nlskb, struct sk_buff *packet,
 241                       bool csum_verify)
 242 {
 243         __u32 flags = 0;
 244
 245         if (packet->ip_summed == CHECKSUM_PARTIAL)
 246                 flags = NFQA_SKB_CSUMNOTREADY;
 247         else if (csum_verify)
 248                 flags = NFQA_SKB_CSUM_NOTVERIFIED;
 249
 250         if (skb_is_gso(packet))
 251                 flags |= NFQA_SKB_GSO;
 252
 253         return flags ? nla_put_be32(nlskb, NFQA_SKB_INFO, htonl(flags)) : 0;
 254 }
 255
 256 static int nfqnl_put_sk_uidgid(struct sk_buff *skb, struct sock *sk)
 257 {
 258         const struct cred *cred;
 259
 260         if (!sk_fullsock(sk))
 261                 return 0;
 262
 263         read_lock_bh(&sk->sk_callback_lock);
 264         if (sk->sk_socket && sk->sk_socket->file) {
 265                 cred = sk->sk_socket->file->f_cred;
 266                 if (nla_put_be32(skb, NFQA_UID,
 267                     htonl(from_kuid_munged(&init_user_ns, cred->fsuid))))
 268                         goto nla_put_failure;
 269                 if (nla_put_be32(skb, NFQA_GID,
 270                     htonl(from_kgid_munged(&init_user_ns, cred->fsgid))))
 271                         goto nla_put_failure;
 272         }
 273         read_unlock_bh(&sk->sk_callback_lock);
 274         return 0;
 275
 276 nla_put_failure:
 277         read_unlock_bh(&sk->sk_callback_lock);
 278         return -1;
 279 }
 280
 281 static u32 nfqnl_get_sk_secctx(struct sk_buff *skb, char **secdata)
 282 {
 283         u32 seclen = 0;
 284 #if IS_ENABLED(CONFIG_NETWORK_SECMARK)
 285         if (!skb || !sk_fullsock(skb->sk))
 286                 return 0;
 287
 288         read_lock_bh(&skb->sk->sk_callback_lock);
 289
 290         if (skb->secmark)
 291                 security_secid_to_secctx(skb->secmark, secdata, &seclen);
 292
 293         read_unlock_bh(&skb->sk->sk_callback_lock);
 294 #endif
 295         return seclen;
 296 }
 297
 298 static u32 nfqnl_get_bridge_size(struct nf_queue_entry *entry)
 299 {
 300         struct sk_buff *entskb = entry->skb;
 301         u32 nlalen = 0;
 302
 303         if (entry->state.pf != PF_BRIDGE || !skb_mac_header_was_set(entskb))
 304                 return 0;
 305
 306         if (skb_vlan_tag_present(entskb))
 307                 nlalen += nla_total_size(nla_total_size(sizeof(__be16)) +
 308                                          nla_total_size(sizeof(__be16)));
 309
 310         if (entskb->network_header > entskb->mac_header)
 311                 nlalen += nla_total_size((entskb->network_header -
 312                                           entskb->mac_header));
 313
 314         return nlalen;
 315 }
 316
 317 static int nfqnl_put_bridge(struct nf_queue_entry *entry, struct sk_buff *skb)
 318 {
 319         struct sk_buff *entskb = entry->skb;
 320
 321         if (entry->state.pf != PF_BRIDGE || !skb_mac_header_was_set(entskb))
 322                 return 0;
 323
 324         if (skb_vlan_tag_present(entskb)) {
 325                 struct nlattr *nest;
 326
 327                 nest = nla_nest_start(skb, NFQA_VLAN | NLA_F_NESTED);
 328                 if (!nest)
 329                         goto nla_put_failure;
 330
 331                 if (nla_put_be16(skb, NFQA_VLAN_TCI, htons(entskb->vlan_tci)) ||
 332                     nla_put_be16(skb, NFQA_VLAN_PROTO, entskb->vlan_proto))
 333                         goto nla_put_failure;
 334
 335                 nla_nest_end(skb, nest);
 336         }
 337
 338         if (entskb->mac_header < entskb->network_header) {
 339                 int len = (int)(entskb->network_header - entskb->mac_header);
 340
 341                 if (nla_put(skb, NFQA_L2HDR, len, skb_mac_header(entskb)))
 342                         goto nla_put_failure;
 343         }
 344
 345         return 0;
 346
 347 nla_put_failure:
 348         return -1;
 349 }
 350
 351 static struct sk_buff *
 352 nfqnl_build_packet_message(struct net *net, struct nfqnl_instance *queue,
 353                            struct nf_queue_entry *entry,
 354                            __be32 **packet_id_ptr)
 355 {
 356         size_t size;
 357         size_t data_len = 0, cap_len = 0;
 358         unsigned int hlen = 0;
 359         struct sk_buff *skb;
 360         struct nlattr *nla;
 361         struct nfqnl_msg_packet_hdr *pmsg;
 362         struct nlmsghdr *nlh;
 363         struct nfgenmsg *nfmsg;
 364         struct sk_buff *entskb = entry->skb;
 365         struct net_device *indev;
 366         struct net_device *outdev;
 367         struct nf_conn *ct = NULL;
 368         enum ip_conntrack_info uninitialized_var(ctinfo);
 369         struct nfnl_ct_hook *nfnl_ct;
 370         bool csum_verify;
 371         char *secdata = NULL;
 372         u32 seclen = 0;
 373
 374         size =    nlmsg_total_size(sizeof(struct nfgenmsg))
 375                 + nla_total_size(sizeof(struct nfqnl_msg_packet_hdr))
 376                 + nla_total_size(sizeof(u_int32_t))     /* ifindex */
 377                 + nla_total_size(sizeof(u_int32_t))     /* ifindex */
 378 #if IS_ENABLED(CONFIG_BRIDGE_NETFILTER)
 379                 + nla_total_size(sizeof(u_int32_t))     /* ifindex */
 380                 + nla_total_size(sizeof(u_int32_t))     /* ifindex */
 381 #endif
 382                 + nla_total_size(sizeof(u_int32_t))     /* mark */
 383                 + nla_total_size(sizeof(struct nfqnl_msg_packet_hw))
 384                 + nla_total_size(sizeof(u_int32_t))     /* skbinfo */
 385                 + nla_total_size(sizeof(u_int32_t));    /* cap_len */
 386
 387         if (entskb->tstamp.tv64)
 388                 size += nla_total_size(sizeof(struct nfqnl_msg_packet_timestamp));
 389
 390         size += nfqnl_get_bridge_size(entry);
 391
 392         if (entry->state.hook <= NF_INET_FORWARD ||
 393            (entry->state.hook == NF_INET_POST_ROUTING && entskb->sk == NULL))
 394                 csum_verify = !skb_csum_unnecessary(entskb);
 395         else
 396                 csum_verify = false;
 397
 398         outdev = entry->state.out;
 399
 400         switch ((enum nfqnl_config_mode)ACCESS_ONCE(queue->copy_mode)) {
 401         case NFQNL_COPY_META:
 402         case NFQNL_COPY_NONE:
 403                 break;
 404
 405         case NFQNL_COPY_PACKET:
 406                 if (!(queue->flags & NFQA_CFG_F_GSO) &&
 407                     entskb->ip_summed == CHECKSUM_PARTIAL &&
 408                     skb_checksum_help(entskb))
 409                         return NULL;
 410
 411                 data_len = ACCESS_ONCE(queue->copy_range);
 412                 if (data_len > entskb->len)
 413                         data_len = entskb->len;
 414
 415                 hlen = skb_zerocopy_headlen(entskb);
 416                 hlen = min_t(unsigned int, hlen, data_len);
 417                 size += sizeof(struct nlattr) + hlen;
 418                 cap_len = entskb->len;
 419                 break;
 420         }
 421
 422         nfnl_ct = rcu_dereference(nfnl_ct_hook);
 423
 424         if (queue->flags & NFQA_CFG_F_CONNTRACK) {
 425                 if (nfnl_ct != NULL) {
 426                         ct = nfnl_ct->get_ct(entskb, &ctinfo);
 427                         if (ct != NULL)
 428                                 size += nfnl_ct->build_size(ct);
 429                 }
 430         }
 431
 432         if (queue->flags & NFQA_CFG_F_UID_GID) {
 433                 size +=  (nla_total_size(sizeof(u_int32_t))     /* uid */
 434                         + nla_total_size(sizeof(u_int32_t)));   /* gid */
 435         }
 436
 437         if ((queue->flags & NFQA_CFG_F_SECCTX) && entskb->sk) {
 438                 seclen = nfqnl_get_sk_secctx(entskb, &secdata);
 439                 if (seclen)
 440                         size += nla_total_size(seclen);
 441         }
 442
 443         skb = alloc_skb(size, GFP_ATOMIC);
 444         if (!skb) {
 445                 skb_tx_error(entskb);
 446                 return NULL;
 447         }
 448
 449         nlh = nlmsg_put(skb, 0, 0,
 450                         NFNL_SUBSYS_QUEUE << 8 | NFQNL_MSG_PACKET,
 451                         sizeof(struct nfgenmsg), 0);
 452         if (!nlh) {
 453                 skb_tx_error(entskb);
 454                 kfree_skb(skb);
 455                 return NULL;
 456         }
 457         nfmsg = nlmsg_data(nlh);
 458         nfmsg->nfgen_family = entry->state.pf;
 459         nfmsg->version = NFNETLINK_V0;
 460         nfmsg->res_id = htons(queue->queue_num);
 461
 462         nla = __nla_reserve(skb, NFQA_PACKET_HDR, sizeof(*pmsg));
 463         pmsg = nla_data(nla);
 464         pmsg->hw_protocol       = entskb->protocol;
 465         pmsg->hook              = entry->state.hook;
 466         *packet_id_ptr          = &pmsg->packet_id;
 467
 468         indev = entry->state.in;
 469         if (indev) {
 470 #if !IS_ENABLED(CONFIG_BRIDGE_NETFILTER)
 471                 if (nla_put_be32(skb, NFQA_IFINDEX_INDEV, htonl(indev->ifindex)))
 472                         goto nla_put_failure;
 473 #else
 474                 if (entry->state.pf == PF_BRIDGE) {
 475                         /* Case 1: indev is physical input device, we need to
 476                          * look for bridge group (when called from
 477                          * netfilter_bridge) */
 478                         if (nla_put_be32(skb, NFQA_IFINDEX_PHYSINDEV,
 479                                          htonl(indev->ifindex)) ||
 480                         /* this is the bridge group "brX" */
 481                         /* rcu_read_lock()ed by __nf_queue */
 482                             nla_put_be32(skb, NFQA_IFINDEX_INDEV,
 483                                          htonl(br_port_get_rcu(indev)->br->dev->ifindex)))
 484                                 goto nla_put_failure;
 485                 } else {
 486                         int physinif;
 487
 488                         /* Case 2: indev is bridge group, we need to look for
 489                          * physical device (when called from ipv4) */
 490                         if (nla_put_be32(skb, NFQA_IFINDEX_INDEV,
 491                                          htonl(indev->ifindex)))
 492                                 goto nla_put_failure;
 493
 494                         physinif = nf_bridge_get_physinif(entskb);
 495                         if (physinif &&
 496                             nla_put_be32(skb, NFQA_IFINDEX_PHYSINDEV,
 497                                          htonl(physinif)))
 498                                 goto nla_put_failure;
 499                 }
 500 #endif
 501         }
 502
 503         if (outdev) {
 504 #if !IS_ENABLED(CONFIG_BRIDGE_NETFILTER)
 505                 if (nla_put_be32(skb, NFQA_IFINDEX_OUTDEV, htonl(outdev->ifindex)))
 506                         goto nla_put_failure;
 507 #else
 508                 if (entry->state.pf == PF_BRIDGE) {
 509                         /* Case 1: outdev is physical output device, we need to
 510                          * look for bridge group (when called from
 511                          * netfilter_bridge) */
 512                         if (nla_put_be32(skb, NFQA_IFINDEX_PHYSOUTDEV,
 513                                          htonl(outdev->ifindex)) ||
 514                         /* this is the bridge group "brX" */
 515                         /* rcu_read_lock()ed by __nf_queue */
 516                             nla_put_be32(skb, NFQA_IFINDEX_OUTDEV,
 517                                          htonl(br_port_get_rcu(outdev)->br->dev->ifindex)))
 518                                 goto nla_put_failure;
 519                 } else {
 520                         int physoutif;
 521
 522                         /* Case 2: outdev is bridge group, we need to look for
 523                          * physical output device (when called from ipv4) */
 524                         if (nla_put_be32(skb, NFQA_IFINDEX_OUTDEV,
 525                                          htonl(outdev->ifindex)))
 526                                 goto nla_put_failure;
 527
 528                         physoutif = nf_bridge_get_physoutif(entskb);
 529                         if (physoutif &&
 530                             nla_put_be32(skb, NFQA_IFINDEX_PHYSOUTDEV,
 531                                          htonl(physoutif)))
 532                                 goto nla_put_failure;
 533                 }
 534 #endif
 535         }
 536
 537         if (entskb->mark &&
 538             nla_put_be32(skb, NFQA_MARK, htonl(entskb->mark)))
 539                 goto nla_put_failure;
 540
 541         if (indev && entskb->dev &&
 542             entskb->mac_header != entskb->network_header) {
 543                 struct nfqnl_msg_packet_hw phw;
 544                 int len;
 545
 546                 memset(&phw, 0, sizeof(phw));
 547                 len = dev_parse_header(entskb, phw.hw_addr);
 548                 if (len) {
 549                         phw.hw_addrlen = htons(len);
 550                         if (nla_put(skb, NFQA_HWADDR, sizeof(phw), &phw))
 551                                 goto nla_put_failure;
 552                 }
 553         }
 554
 555         if (nfqnl_put_bridge(entry, skb) < 0)
 556                 goto nla_put_failure;
 557
 558         if (entskb->tstamp.tv64) {
 559                 struct nfqnl_msg_packet_timestamp ts;
 560                 struct timespec64 kts = ktime_to_timespec64(entskb->tstamp);
 561
 562                 ts.sec = cpu_to_be64(kts.tv_sec);
 563                 ts.usec = cpu_to_be64(kts.tv_nsec / NSEC_PER_USEC);
 564
 565                 if (nla_put(skb, NFQA_TIMESTAMP, sizeof(ts), &ts))
 566                         goto nla_put_failure;
 567         }
 568
 569         if ((queue->flags & NFQA_CFG_F_UID_GID) && entskb->sk &&
 570             nfqnl_put_sk_uidgid(skb, entskb->sk) < 0)
 571                 goto nla_put_failure;
 572
 573         if (seclen && nla_put(skb, NFQA_SECCTX, seclen, secdata))
 574                 goto nla_put_failure;
 575
 576         if (ct && nfnl_ct->build(skb, ct, ctinfo, NFQA_CT, NFQA_CT_INFO) < 0)
 577                 goto nla_put_failure;
 578
 579         if (cap_len > data_len &&
 580             nla_put_be32(skb, NFQA_CAP_LEN, htonl(cap_len)))
 581                 goto nla_put_failure;
 582
 583         if (nfqnl_put_packet_info(skb, entskb, csum_verify))
 584                 goto nla_put_failure;
 585
 586         if (data_len) {
 587                 struct nlattr *nla;
 588
 589                 if (skb_tailroom(skb) < sizeof(*nla) + hlen)
 590                         goto nla_put_failure;
 591
 592                 nla = (struct nlattr *)skb_put(skb, sizeof(*nla));
 593                 nla->nla_type = NFQA_PAYLOAD;
 594                 nla->nla_len = nla_attr_size(data_len);
 595
 596                 if (skb_zerocopy(skb, entskb, data_len, hlen))
 597                         goto nla_put_failure;
 598         }
 599
 600         nlh->nlmsg_len = skb->len;
 601         return skb;
 602
 603 nla_put_failure:
 604         skb_tx_error(entskb);
 605         kfree_skb(skb);
 606         net_err_ratelimited("nf_queue: error creating packet message\n");
 607         return NULL;
 608 }
 609
 610 static int
 611 __nfqnl_enqueue_packet(struct net *net, struct nfqnl_instance *queue,
 612                         struct nf_queue_entry *entry)
 613 {
 614         struct sk_buff *nskb;
 615         int err = -ENOBUFS;
 616         __be32 *packet_id_ptr;
 617         int failopen = 0;
 618
 619         nskb = nfqnl_build_packet_message(net, queue, entry, &packet_id_ptr);
 620         if (nskb == NULL) {
 621                 err = -ENOMEM;
 622                 goto err_out;
 623         }
 624         spin_lock_bh(&queue->lock);
 625
 626         if (queue->queue_total >= queue->queue_maxlen) {
 627                 if (queue->flags & NFQA_CFG_F_FAIL_OPEN) {
 628                         failopen = 1;
 629                         err = 0;
 630                 } else {
 631                         queue->queue_dropped++;
 632                         net_warn_ratelimited("nf_queue: full at %d entries, dropping packets(s)\n",
 633                                              queue->queue_total);
 634                 }
 635                 goto err_out_free_nskb;
 636         }
 637         entry->id = ++queue->id_sequence;
 638         *packet_id_ptr = htonl(entry->id);
 639
 640         /* nfnetlink_unicast will either free the nskb or add it to a socket */
 641         err = nfnetlink_unicast(nskb, net, queue->peer_portid, MSG_DONTWAIT);
 642         if (err < 0) {
 643                 if (queue->flags & NFQA_CFG_F_FAIL_OPEN) {
 644                         failopen = 1;
 645                         err = 0;
 646                 } else {
 647                         queue->queue_user_dropped++;
 648                 }
 649                 goto err_out_unlock;
 650         }
 651
 652         __enqueue_entry(queue, entry);
 653
 654         spin_unlock_bh(&queue->lock);
 655         return 0;
 656
 657 err_out_free_nskb:
 658         kfree_skb(nskb);
 659 err_out_unlock:
 660         spin_unlock_bh(&queue->lock);
 661         if (failopen)
 662                 nf_reinject(entry, NF_ACCEPT);
 663 err_out:
 664         return err;
 665 }
 666
 667 static struct nf_queue_entry *
 668 nf_queue_entry_dup(struct nf_queue_entry *e)
 669 {
 670         struct nf_queue_entry *entry = kmemdup(e, e->size, GFP_ATOMIC);
 671         if (entry)
 672                 nf_queue_entry_get_refs(entry);
 673         return entry;
 674 }
 675
 676 #if IS_ENABLED(CONFIG_BRIDGE_NETFILTER)
 677 /* When called from bridge netfilter, skb->data must point to MAC header
 678  * before calling skb_gso_segment(). Else, original MAC header is lost
 679  * and segmented skbs will be sent to wrong destination.
 680  */
 681 static void nf_bridge_adjust_skb_data(struct sk_buff *skb)
 682 {
 683         if (skb->nf_bridge)
 684                 __skb_push(skb, skb->network_header - skb->mac_header);
 685 }
 686
 687 static void nf_bridge_adjust_segmented_data(struct sk_buff *skb)
 688 {
 689         if (skb->nf_bridge)
 690                 __skb_pull(skb, skb->network_header - skb->mac_header);
 691 }
 692 #else
 693 #define nf_bridge_adjust_skb_data(s) do {} while (0)
 694 #define nf_bridge_adjust_segmented_data(s) do {} while (0)
 695 #endif
 696
 697 static void free_entry(struct nf_queue_entry *entry)
 698 {
 699         nf_queue_entry_release_refs(entry);
 700         kfree(entry);
 701 }
 702
 703 static int
 704 __nfqnl_enqueue_packet_gso(struct net *net, struct nfqnl_instance *queue,
 705                            struct sk_buff *skb, struct nf_queue_entry *entry)
 706 {
 707         int ret = -ENOMEM;
 708         struct nf_queue_entry *entry_seg;
 709
 710         nf_bridge_adjust_segmented_data(skb);
 711
 712         if (skb->next == NULL) { /* last packet, no need to copy entry */
 713                 struct sk_buff *gso_skb = entry->skb;
 714                 entry->skb = skb;
 715                 ret = __nfqnl_enqueue_packet(net, queue, entry);
 716                 if (ret)
 717                         entry->skb = gso_skb;
 718                 return ret;
 719         }
 720
 721         skb->next = NULL;
 722
 723         entry_seg = nf_queue_entry_dup(entry);
 724         if (entry_seg) {
 725                 entry_seg->skb = skb;
 726                 ret = __nfqnl_enqueue_packet(net, queue, entry_seg);
 727                 if (ret)
 728                         free_entry(entry_seg);
 729         }
 730         return ret;
 731 }
 732
 733 static int
 734 nfqnl_enqueue_packet(struct nf_queue_entry *entry, unsigned int queuenum)
 735 {
 736         unsigned int queued;
 737         struct nfqnl_instance *queue;
 738         struct sk_buff *skb, *segs;
 739         int err = -ENOBUFS;
 740         struct net *net = entry->state.net;
 741         struct nfnl_queue_net *q = nfnl_queue_pernet(net);
 742
 743         /* rcu_read_lock()ed by nf_hook_thresh */
 744         queue = instance_lookup(q, queuenum);
 745         if (!queue)
 746                 return -ESRCH;
 747
 748         if (queue->copy_mode == NFQNL_COPY_NONE)
 749                 return -EINVAL;
 750
 751         skb = entry->skb;
 752
 753         switch (entry->state.pf) {
 754         case NFPROTO_IPV4:
 755                 skb->protocol = htons(ETH_P_IP);
 756                 break;
 757         case NFPROTO_IPV6:
 758                 skb->protocol = htons(ETH_P_IPV6);
 759                 break;
 760         }
 761
 762         if ((queue->flags & NFQA_CFG_F_GSO) || !skb_is_gso(skb))
 763                 return __nfqnl_enqueue_packet(net, queue, entry);
 764
 765         nf_bridge_adjust_skb_data(skb);
 766         segs = skb_gso_segment(skb, 0);
 767         /* Does not use PTR_ERR to limit the number of error codes that can be
 768          * returned by nf_queue.  For instance, callers rely on -ESRCH to
 769          * mean 'ignore this hook'.
 770          */
 771         if (IS_ERR_OR_NULL(segs))
 772                 goto out_err;
 773         queued = 0;
 774         err = 0;
 775         do {
 776                 struct sk_buff *nskb = segs->next;
 777                 if (err == 0)
 778                         err = __nfqnl_enqueue_packet_gso(net, queue,
 779                                                         segs, entry);
 780                 if (err == 0)
 781                         queued++;
 782                 else
 783                         kfree_skb(segs);
 784                 segs = nskb;
 785         } while (segs);
 786
 787         if (queued) {
 788                 if (err) /* some segments are already queued */
 789                         free_entry(entry);
 790                 kfree_skb(skb);
 791                 return 0;
 792         }
 793  out_err:
 794         nf_bridge_adjust_segmented_data(skb);
 795         return err;
 796 }
 797
 798 static int
 799 nfqnl_mangle(void *data, int data_len, struct nf_queue_entry *e, int diff)
 800 {
 801         struct sk_buff *nskb;
 802
 803         if (diff < 0) {
 804                 if (pskb_trim(e->skb, data_len))
 805                         return -ENOMEM;
 806         } else if (diff > 0) {
 807                 if (data_len > 0xFFFF)
 808                         return -EINVAL;
 809                 if (diff > skb_tailroom(e->skb)) {
 810                         nskb = skb_copy_expand(e->skb, skb_headroom(e->skb),
 811                                                diff, GFP_ATOMIC);
 812                         if (!nskb) {
 813                                 printk(KERN_WARNING "nf_queue: OOM "
 814                                       "in mangle, dropping packet\n");
 815                                 return -ENOMEM;
 816                         }
 817                         kfree_skb(e->skb);
 818                         e->skb = nskb;
 819                 }
 820                 skb_put(e->skb, diff);
 821         }
 822         if (!skb_make_writable(e->skb, data_len))
 823                 return -ENOMEM;
 824         skb_copy_to_linear_data(e->skb, data, data_len);
 825         e->skb->ip_summed = CHECKSUM_NONE;
 826         return 0;
 827 }
 828
 829 static int
 830 nfqnl_set_mode(struct nfqnl_instance *queue,
 831                unsigned char mode, unsigned int range)
 832 {
 833         int status = 0;
 834
 835         spin_lock_bh(&queue->lock);
 836         switch (mode) {
 837         case NFQNL_COPY_NONE:
 838         case NFQNL_COPY_META:
 839                 queue->copy_mode = mode;
 840                 queue->copy_range = 0;
 841                 break;
 842
 843         case NFQNL_COPY_PACKET:
 844                 queue->copy_mode = mode;
 845                 if (range == 0 || range > NFQNL_MAX_COPY_RANGE)
 846                         queue->copy_range = NFQNL_MAX_COPY_RANGE;
 847                 else
 848                         queue->copy_range = range;
 849                 break;
 850
 851         default:
 852                 status = -EINVAL;
 853
 854         }
 855         spin_unlock_bh(&queue->lock);
 856
 857         return status;
 858 }
 859
 860 static int
 861 dev_cmp(struct nf_queue_entry *entry, unsigned long ifindex)
 862 {
 863         if (entry->state.in)
 864                 if (entry->state.in->ifindex == ifindex)
 865                         return 1;
 866         if (entry->state.out)
 867                 if (entry->state.out->ifindex == ifindex)
 868                         return 1;
 869 #if IS_ENABLED(CONFIG_BRIDGE_NETFILTER)
 870         if (entry->skb->nf_bridge) {
 871                 int physinif, physoutif;
 872
 873                 physinif = nf_bridge_get_physinif(entry->skb);
 874                 physoutif = nf_bridge_get_physoutif(entry->skb);
 875
 876                 if (physinif == ifindex || physoutif == ifindex)
 877                         return 1;
 878         }
 879 #endif
 880         return 0;
 881 }
 882
 883 /* drop all packets with either indev or outdev == ifindex from all queue
 884  * instances */
 885 static void
 886 nfqnl_dev_drop(struct net *net, int ifindex)
 887 {
 888         int i;
 889         struct nfnl_queue_net *q = nfnl_queue_pernet(net);
 890
 891         rcu_read_lock();
 892
 893         for (i = 0; i < INSTANCE_BUCKETS; i++) {
 894                 struct nfqnl_instance *inst;
 895                 struct hlist_head *head = &q->instance_table[i];
 896
 897                 hlist_for_each_entry_rcu(inst, head, hlist)
 898                         nfqnl_flush(inst, dev_cmp, ifindex);
 899         }
 900
 901         rcu_read_unlock();
 902 }
 903
 904 static int
 905 nfqnl_rcv_dev_event(struct notifier_block *this,
 906                     unsigned long event, void *ptr)
 907 {
 908         struct net_device *dev = netdev_notifier_info_to_dev(ptr);
 909
 910         /* Drop any packets associated with the downed device */
 911         if (event == NETDEV_DOWN)
 912                 nfqnl_dev_drop(dev_net(dev), dev->ifindex);
 913         return NOTIFY_DONE;
 914 }
 915
 916 static struct notifier_block nfqnl_dev_notifier = {
 917         .notifier_call  = nfqnl_rcv_dev_event,
 918 };
 919
 920 static int nf_hook_cmp(struct nf_queue_entry *entry, unsigned long entry_ptr)
 921 {
 922         return rcu_access_pointer(entry->state.hook_entries) ==
 923                 (struct nf_hook_entry *)entry_ptr;
 924 }
 925
 926 static void nfqnl_nf_hook_drop(struct net *net,
 927                                const struct nf_hook_entry *hook)
 928 {
 929         struct nfnl_queue_net *q = nfnl_queue_pernet(net);
 930         int i;
 931
 932         rcu_read_lock();
 933         for (i = 0; i < INSTANCE_BUCKETS; i++) {
 934                 struct nfqnl_instance *inst;
 935                 struct hlist_head *head = &q->instance_table[i];
 936
 937                 hlist_for_each_entry_rcu(inst, head, hlist)
 938                         nfqnl_flush(inst, nf_hook_cmp, (unsigned long)hook);
 939         }
 940         rcu_read_unlock();
 941 }
 942
 943 static int
 944 nfqnl_rcv_nl_event(struct notifier_block *this,
 945                    unsigned long event, void *ptr)
 946 {
 947         struct netlink_notify *n = ptr;
 948         struct nfnl_queue_net *q = nfnl_queue_pernet(n->net);
 949
 950         if (event == NETLINK_URELEASE && n->protocol == NETLINK_NETFILTER) {
 951                 int i;
 952
 953                 /* destroy all instances for this portid */
 954                 spin_lock(&q->instances_lock);
 955                 for (i = 0; i < INSTANCE_BUCKETS; i++) {
 956                         struct hlist_node *t2;
 957                         struct nfqnl_instance *inst;
 958                         struct hlist_head *head = &q->instance_table[i];
 959
 960                         hlist_for_each_entry_safe(inst, t2, head, hlist) {
 961                                 if (n->portid == inst->peer_portid)
 962                                         __instance_destroy(inst);
 963                         }
 964                 }
 965                 spin_unlock(&q->instances_lock);
 966         }
 967         return NOTIFY_DONE;
 968 }
 969
 970 static struct notifier_block nfqnl_rtnl_notifier = {
 971         .notifier_call  = nfqnl_rcv_nl_event,
 972 };
 973
 974 static const struct nla_policy nfqa_vlan_policy[NFQA_VLAN_MAX + 1] = {
 975         [NFQA_VLAN_TCI]         = { .type = NLA_U16},
 976         [NFQA_VLAN_PROTO]       = { .type = NLA_U16},
 977 };
 978
 979 static const struct nla_policy nfqa_verdict_policy[NFQA_MAX+1] = {
 980         [NFQA_VERDICT_HDR]      = { .len = sizeof(struct nfqnl_msg_verdict_hdr) },
 981         [NFQA_MARK]             = { .type = NLA_U32 },
 982         [NFQA_PAYLOAD]          = { .type = NLA_UNSPEC },
 983         [NFQA_CT]               = { .type = NLA_UNSPEC },
 984         [NFQA_EXP]              = { .type = NLA_UNSPEC },
 985         [NFQA_VLAN]             = { .type = NLA_NESTED },
 986 };
 987
 988 static const struct nla_policy nfqa_verdict_batch_policy[NFQA_MAX+1] = {
 989         [NFQA_VERDICT_HDR]      = { .len = sizeof(struct nfqnl_msg_verdict_hdr) },
 990         [NFQA_MARK]             = { .type = NLA_U32 },
 991 };
 992
 993 static struct nfqnl_instance *
 994 verdict_instance_lookup(struct nfnl_queue_net *q, u16 queue_num, u32 nlportid)
 995 {
 996         struct nfqnl_instance *queue;
 997
 998         queue = instance_lookup(q, queue_num);
 999         if (!queue)
1000                 return ERR_PTR(-ENODEV);
1001
1002         if (queue->peer_portid != nlportid)
1003                 return ERR_PTR(-EPERM);
1004
1005         return queue;
1006 }
1007
1008 static struct nfqnl_msg_verdict_hdr*
1009 verdicthdr_get(const struct nlattr * const nfqa[])
1010 {
1011         struct nfqnl_msg_verdict_hdr *vhdr;
1012         unsigned int verdict;
1013
1014         if (!nfqa[NFQA_VERDICT_HDR])
1015                 return NULL;
1016
1017         vhdr = nla_data(nfqa[NFQA_VERDICT_HDR]);
1018         verdict = ntohl(vhdr->verdict) & NF_VERDICT_MASK;
1019         if (verdict > NF_MAX_VERDICT || verdict == NF_STOLEN)
1020                 return NULL;
1021         return vhdr;
1022 }
1023
1024 static int nfq_id_after(unsigned int id, unsigned int max)
1025 {
1026         return (int)(id - max) > 0;
1027 }
1028
1029 static int nfqnl_recv_verdict_batch(struct net *net, struct sock *ctnl,
1030                                     struct sk_buff *skb,
1031                                     const struct nlmsghdr *nlh,
1032                                     const struct nlattr * const nfqa[])
1033 {
1034         struct nfgenmsg *nfmsg = nlmsg_data(nlh);
1035         struct nf_queue_entry *entry, *tmp;
1036         unsigned int verdict, maxid;
1037         struct nfqnl_msg_verdict_hdr *vhdr;
1038         struct nfqnl_instance *queue;
1039         LIST_HEAD(batch_list);
1040         u16 queue_num = ntohs(nfmsg->res_id);
1041         struct nfnl_queue_net *q = nfnl_queue_pernet(net);
1042
1043         queue = verdict_instance_lookup(q, queue_num,
1044                                         NETLINK_CB(skb).portid);
1045         if (IS_ERR(queue))
1046                 return PTR_ERR(queue);
1047
1048         vhdr = verdicthdr_get(nfqa);
1049         if (!vhdr)
1050                 return -EINVAL;
1051
1052         verdict = ntohl(vhdr->verdict);
1053         maxid = ntohl(vhdr->id);
1054
1055         spin_lock_bh(&queue->lock);
1056
1057         list_for_each_entry_safe(entry, tmp, &queue->queue_list, list) {
1058                 if (nfq_id_after(entry->id, maxid))
1059                         break;
1060                 __dequeue_entry(queue, entry);
1061                 list_add_tail(&entry->list, &batch_list);
1062         }
1063
1064         spin_unlock_bh(&queue->lock);
1065
1066         if (list_empty(&batch_list))
1067                 return -ENOENT;
1068
1069         list_for_each_entry_safe(entry, tmp, &batch_list, list) {
1070                 if (nfqa[NFQA_MARK])
1071                         entry->skb->mark = ntohl(nla_get_be32(nfqa[NFQA_MARK]));
1072                 nf_reinject(entry, verdict);
1073         }
1074         return 0;
1075 }
1076
1077 static struct nf_conn *nfqnl_ct_parse(struct nfnl_ct_hook *nfnl_ct,
1078                                       const struct nlmsghdr *nlh,
1079                                       const struct nlattr * const nfqa[],
1080                                       struct nf_queue_entry *entry,
1081                                       enum ip_conntrack_info *ctinfo)
1082 {
1083         struct nf_conn *ct;
1084
1085         ct = nfnl_ct->get_ct(entry->skb, ctinfo);
1086         if (ct == NULL)
1087                 return NULL;
1088
1089         if (nfnl_ct->parse(nfqa[NFQA_CT], ct) < 0)
1090                 return NULL;
1091
1092         if (nfqa[NFQA_EXP])
1093                 nfnl_ct->attach_expect(nfqa[NFQA_EXP], ct,
1094                                       NETLINK_CB(entry->skb).portid,
1095                                       nlmsg_report(nlh));
1096         return ct;
1097 }
1098
1099 static int nfqa_parse_bridge(struct nf_queue_entry *entry,
1100                              const struct nlattr * const nfqa[])
1101 {
1102         if (nfqa[NFQA_VLAN]) {
1103                 struct nlattr *tb[NFQA_VLAN_MAX + 1];
1104                 int err;
1105
1106                 err = nla_parse_nested(tb, NFQA_VLAN_MAX, nfqa[NFQA_VLAN],
1107                                        nfqa_vlan_policy);
1108                 if (err < 0)
1109                         return err;
1110
1111                 if (!tb[NFQA_VLAN_TCI] || !tb[NFQA_VLAN_PROTO])
1112                         return -EINVAL;
1113
1114                 entry->skb->vlan_tci = ntohs(nla_get_be16(tb[NFQA_VLAN_TCI]));
1115                 entry->skb->vlan_proto = nla_get_be16(tb[NFQA_VLAN_PROTO]);
1116         }
1117
1118         if (nfqa[NFQA_L2HDR]) {
1119                 int mac_header_len = entry->skb->network_header -
1120                         entry->skb->mac_header;
1121
1122                 if (mac_header_len != nla_len(nfqa[NFQA_L2HDR]))
1123                         return -EINVAL;
1124                 else if (mac_header_len > 0)
1125                         memcpy(skb_mac_header(entry->skb),
1126                                nla_data(nfqa[NFQA_L2HDR]),
1127                                mac_header_len);
1128         }
1129
1130         return 0;
1131 }
1132
1133 static int nfqnl_recv_verdict(struct net *net, struct sock *ctnl,
1134                               struct sk_buff *skb,
1135                               const struct nlmsghdr *nlh,
1136                               const struct nlattr * const nfqa[])
1137 {
1138         struct nfgenmsg *nfmsg = nlmsg_data(nlh);
1139         u_int16_t queue_num = ntohs(nfmsg->res_id);
1140         struct nfqnl_msg_verdict_hdr *vhdr;
1141         struct nfqnl_instance *queue;
1142         unsigned int verdict;
1143         struct nf_queue_entry *entry;
1144         enum ip_conntrack_info uninitialized_var(ctinfo);
1145         struct nfnl_ct_hook *nfnl_ct;
1146         struct nf_conn *ct = NULL;
1147         struct nfnl_queue_net *q = nfnl_queue_pernet(net);
1148         int err;
1149
1150         queue = verdict_instance_lookup(q, queue_num,
1151                                         NETLINK_CB(skb).portid);
1152         if (IS_ERR(queue))
1153                 return PTR_ERR(queue);
1154
1155         vhdr = verdicthdr_get(nfqa);
1156         if (!vhdr)
1157                 return -EINVAL;
1158
1159         verdict = ntohl(vhdr->verdict);
1160
1161         entry = find_dequeue_entry(queue, ntohl(vhdr->id));
1162         if (entry == NULL)
1163                 return -ENOENT;
1164
1165         /* rcu lock already held from nfnl->call_rcu. */
1166         nfnl_ct = rcu_dereference(nfnl_ct_hook);
1167
1168         if (nfqa[NFQA_CT]) {
1169                 if (nfnl_ct != NULL)
1170                         ct = nfqnl_ct_parse(nfnl_ct, nlh, nfqa, entry, &ctinfo);
1171         }
1172
1173         if (entry->state.pf == PF_BRIDGE) {
1174                 err = nfqa_parse_bridge(entry, nfqa);
1175                 if (err < 0)
1176                         return err;
1177         }
1178
1179         if (nfqa[NFQA_PAYLOAD]) {
1180                 u16 payload_len = nla_len(nfqa[NFQA_PAYLOAD]);
1181                 int diff = payload_len - entry->skb->len;
1182
1183                 if (nfqnl_mangle(nla_data(nfqa[NFQA_PAYLOAD]),
1184                                  payload_len, entry, diff) < 0)
1185                         verdict = NF_DROP;
1186
1187                 if (ct && diff)
1188                         nfnl_ct->seq_adjust(entry->skb, ct, ctinfo, diff);
1189         }
1190
1191         if (nfqa[NFQA_MARK])
1192                 entry->skb->mark = ntohl(nla_get_be32(nfqa[NFQA_MARK]));
1193
1194         nf_reinject(entry, verdict);
1195         return 0;
1196 }
1197
1198 static int nfqnl_recv_unsupp(struct net *net, struct sock *ctnl,
1199                              struct sk_buff *skb, const struct nlmsghdr *nlh,
1200                              const struct nlattr * const nfqa[])
1201 {
1202         return -ENOTSUPP;
1203 }
1204
1205 static const struct nla_policy nfqa_cfg_policy[NFQA_CFG_MAX+1] = {
1206         [NFQA_CFG_CMD]          = { .len = sizeof(struct nfqnl_msg_config_cmd) },
1207         [NFQA_CFG_PARAMS]       = { .len = sizeof(struct nfqnl_msg_config_params) },
1208 };
1209
1210 static const struct nf_queue_handler nfqh = {
1211         .outfn          = &nfqnl_enqueue_packet,
1212         .nf_hook_drop   = &nfqnl_nf_hook_drop,
1213 };
1214
1215 static int nfqnl_recv_config(struct net *net, struct sock *ctnl,
1216                              struct sk_buff *skb, const struct nlmsghdr *nlh,
1217                              const struct nlattr * const nfqa[])
1218 {
1219         struct nfgenmsg *nfmsg = nlmsg_data(nlh);
1220         u_int16_t queue_num = ntohs(nfmsg->res_id);
1221         struct nfqnl_instance *queue;
1222         struct nfqnl_msg_config_cmd *cmd = NULL;
1223         struct nfnl_queue_net *q = nfnl_queue_pernet(net);
1224         __u32 flags = 0, mask = 0;
1225         int ret = 0;
1226
1227         if (nfqa[NFQA_CFG_CMD]) {
1228                 cmd = nla_data(nfqa[NFQA_CFG_CMD]);
1229
1230                 /* Obsolete commands without queue context */
1231                 switch (cmd->command) {
1232                 case NFQNL_CFG_CMD_PF_BIND: return 0;
1233                 case NFQNL_CFG_CMD_PF_UNBIND: return 0;
1234                 }
1235         }
1236
1237         /* Check if we support these flags in first place, dependencies should
1238          * be there too not to break atomicity.
1239          */
1240         if (nfqa[NFQA_CFG_FLAGS]) {
1241                 if (!nfqa[NFQA_CFG_MASK]) {
1242                         /* A mask is needed to specify which flags are being
1243                          * changed.
1244                          */
1245                         return -EINVAL;
1246                 }
1247
1248                 flags = ntohl(nla_get_be32(nfqa[NFQA_CFG_FLAGS]));
1249                 mask = ntohl(nla_get_be32(nfqa[NFQA_CFG_MASK]));
1250
1251                 if (flags >= NFQA_CFG_F_MAX)
1252                         return -EOPNOTSUPP;
1253
1254 #if !IS_ENABLED(CONFIG_NETWORK_SECMARK)
1255                 if (flags & mask & NFQA_CFG_F_SECCTX)
1256                         return -EOPNOTSUPP;
1257 #endif
1258                 if ((flags & mask & NFQA_CFG_F_CONNTRACK) &&
1259                     !rcu_access_pointer(nfnl_ct_hook)) {
1260 #ifdef CONFIG_MODULES
1261                         nfnl_unlock(NFNL_SUBSYS_QUEUE);
1262                         request_module("ip_conntrack_netlink");
1263                         nfnl_lock(NFNL_SUBSYS_QUEUE);
1264                         if (rcu_access_pointer(nfnl_ct_hook))
1265                                 return -EAGAIN;
1266 #endif
1267                         return -EOPNOTSUPP;
1268                 }
1269         }
1270
1271         rcu_read_lock();
1272         queue = instance_lookup(q, queue_num);
1273         if (queue && queue->peer_portid != NETLINK_CB(skb).portid) {
1274                 ret = -EPERM;
1275                 goto err_out_unlock;
1276         }
1277
1278         if (cmd != NULL) {
1279                 switch (cmd->command) {
1280                 case NFQNL_CFG_CMD_BIND:
1281                         if (queue) {
1282                                 ret = -EBUSY;
1283                                 goto err_out_unlock;
1284                         }
1285                         queue = instance_create(q, queue_num,
1286                                                 NETLINK_CB(skb).portid);
1287                         if (IS_ERR(queue)) {
1288                                 ret = PTR_ERR(queue);
1289                                 goto err_out_unlock;
1290                         }
1291                         break;
1292                 case NFQNL_CFG_CMD_UNBIND:
1293                         if (!queue) {
1294                                 ret = -ENODEV;
1295                                 goto err_out_unlock;
1296                         }
1297                         instance_destroy(q, queue);
1298                         goto err_out_unlock;
1299                 case NFQNL_CFG_CMD_PF_BIND:
1300                 case NFQNL_CFG_CMD_PF_UNBIND:
1301                         break;
1302                 default:
1303                         ret = -ENOTSUPP;
1304                         goto err_out_unlock;
1305                 }
1306         }
1307
1308         if (!queue) {
1309                 ret = -ENODEV;
1310                 goto err_out_unlock;
1311         }
1312
1313         if (nfqa[NFQA_CFG_PARAMS]) {
1314                 struct nfqnl_msg_config_params *params =
1315                         nla_data(nfqa[NFQA_CFG_PARAMS]);
1316
1317                 nfqnl_set_mode(queue, params->copy_mode,
1318                                 ntohl(params->copy_range));
1319         }
1320
1321         if (nfqa[NFQA_CFG_QUEUE_MAXLEN]) {
1322                 __be32 *queue_maxlen = nla_data(nfqa[NFQA_CFG_QUEUE_MAXLEN]);
1323
1324                 spin_lock_bh(&queue->lock);
1325                 queue->queue_maxlen = ntohl(*queue_maxlen);
1326                 spin_unlock_bh(&queue->lock);
1327         }
1328
1329         if (nfqa[NFQA_CFG_FLAGS]) {
1330                 spin_lock_bh(&queue->lock);
1331                 queue->flags &= ~mask;
1332                 queue->flags |= flags & mask;
1333                 spin_unlock_bh(&queue->lock);
1334         }
1335
1336 err_out_unlock:
1337         rcu_read_unlock();
1338         return ret;
1339 }
1340
1341 static const struct nfnl_callback nfqnl_cb[NFQNL_MSG_MAX] = {
1342         [NFQNL_MSG_PACKET]      = { .call_rcu = nfqnl_recv_unsupp,
1343                                     .attr_count = NFQA_MAX, },
1344         [NFQNL_MSG_VERDICT]     = { .call_rcu = nfqnl_recv_verdict,
1345                                     .attr_count = NFQA_MAX,
1346                                     .policy = nfqa_verdict_policy },
1347         [NFQNL_MSG_CONFIG]      = { .call = nfqnl_recv_config,
1348                                     .attr_count = NFQA_CFG_MAX,
1349                                     .policy = nfqa_cfg_policy },
1350         [NFQNL_MSG_VERDICT_BATCH]={ .call_rcu = nfqnl_recv_verdict_batch,
1351                                     .attr_count = NFQA_MAX,
1352                                     .policy = nfqa_verdict_batch_policy },
1353 };
1354
1355 static const struct nfnetlink_subsystem nfqnl_subsys = {
1356         .name           = "nf_queue",
1357         .subsys_id      = NFNL_SUBSYS_QUEUE,
1358         .cb_count       = NFQNL_MSG_MAX,
1359         .cb             = nfqnl_cb,
1360 };
1361
1362 #ifdef CONFIG_PROC_FS
1363 struct iter_state {
1364         struct seq_net_private p;
1365         unsigned int bucket;
1366 };
1367
1368 static struct hlist_node *get_first(struct seq_file *seq)
1369 {
1370         struct iter_state *st = seq->private;
1371         struct net *net;
1372         struct nfnl_queue_net *q;
1373
1374         if (!st)
1375                 return NULL;
1376
1377         net = seq_file_net(seq);
1378         q = nfnl_queue_pernet(net);
1379         for (st->bucket = 0; st->bucket < INSTANCE_BUCKETS; st->bucket++) {
1380                 if (!hlist_empty(&q->instance_table[st->bucket]))
1381                         return q->instance_table[st->bucket].first;
1382         }
1383         return NULL;
1384 }
1385
1386 static struct hlist_node *get_next(struct seq_file *seq, struct hlist_node *h)
1387 {
1388         struct iter_state *st = seq->private;
1389         struct net *net = seq_file_net(seq);
1390
1391         h = h->next;
1392         while (!h) {
1393                 struct nfnl_queue_net *q;
1394
1395                 if (++st->bucket >= INSTANCE_BUCKETS)
1396                         return NULL;
1397
1398                 q = nfnl_queue_pernet(net);
1399                 h = q->instance_table[st->bucket].first;
1400         }
1401         return h;
1402 }
1403
1404 static struct hlist_node *get_idx(struct seq_file *seq, loff_t pos)
1405 {
1406         struct hlist_node *head;
1407         head = get_first(seq);
1408
1409         if (head)
1410                 while (pos && (head = get_next(seq, head)))
1411                         pos--;
1412         return pos ? NULL : head;
1413 }
1414
1415 static void *seq_start(struct seq_file *s, loff_t *pos)
1416         __acquires(nfnl_queue_pernet(seq_file_net(s))->instances_lock)
1417 {
1418         spin_lock(&nfnl_queue_pernet(seq_file_net(s))->instances_lock);
1419         return get_idx(s, *pos);
1420 }
1421
1422 static void *seq_next(struct seq_file *s, void *v, loff_t *pos)
1423 {
1424         (*pos)++;
1425         return get_next(s, v);
1426 }
1427
1428 static void seq_stop(struct seq_file *s, void *v)
1429         __releases(nfnl_queue_pernet(seq_file_net(s))->instances_lock)
1430 {
1431         spin_unlock(&nfnl_queue_pernet(seq_file_net(s))->instances_lock);
1432 }
1433
1434 static int seq_show(struct seq_file *s, void *v)
1435 {
1436         const struct nfqnl_instance *inst = v;
1437
1438         seq_printf(s, "%5u %6u %5u %1u %5u %5u %5u %8u %2d\n",
1439                    inst->queue_num,
1440                    inst->peer_portid, inst->queue_total,
1441                    inst->copy_mode, inst->copy_range,
1442                    inst->queue_dropped, inst->queue_user_dropped,
1443                    inst->id_sequence, 1);
1444         return 0;
1445 }
1446
1447 static const struct seq_operations nfqnl_seq_ops = {
1448         .start  = seq_start,
1449         .next   = seq_next,
1450         .stop   = seq_stop,
1451         .show   = seq_show,
1452 };
1453
1454 static int nfqnl_open(struct inode *inode, struct file *file)
1455 {
1456         return seq_open_net(inode, file, &nfqnl_seq_ops,
1457                         sizeof(struct iter_state));
1458 }
1459
1460 static const struct file_operations nfqnl_file_ops = {
1461         .owner   = THIS_MODULE,
1462         .open    = nfqnl_open,
1463         .read    = seq_read,
1464         .llseek  = seq_lseek,
1465         .release = seq_release_net,
1466 };
1467
1468 #endif /* PROC_FS */
1469
1470 static int __net_init nfnl_queue_net_init(struct net *net)
1471 {
1472         unsigned int i;
1473         struct nfnl_queue_net *q = nfnl_queue_pernet(net);
1474
1475         for (i = 0; i < INSTANCE_BUCKETS; i++)
1476                 INIT_HLIST_HEAD(&q->instance_table[i]);
1477
1478         spin_lock_init(&q->instances_lock);
1479
1480 #ifdef CONFIG_PROC_FS
1481         if (!proc_create("nfnetlink_queue", 0440,
1482                          net->nf.proc_netfilter, &nfqnl_file_ops))
1483                 return -ENOMEM;
1484 #endif
1485         nf_register_queue_handler(net, &nfqh);
1486         return 0;
1487 }
1488
1489 static void __net_exit nfnl_queue_net_exit(struct net *net)
1490 {
1491         nf_unregister_queue_handler(net);
1492 #ifdef CONFIG_PROC_FS
1493         remove_proc_entry("nfnetlink_queue", net->nf.proc_netfilter);
1494 #endif
1495 }
1496
1497 static void nfnl_queue_net_exit_batch(struct list_head *net_exit_list)
1498 {
1499         synchronize_rcu();
1500 }
1501
1502 static struct pernet_operations nfnl_queue_net_ops = {
1503         .init           = nfnl_queue_net_init,
1504         .exit           = nfnl_queue_net_exit,
1505         .exit_batch     = nfnl_queue_net_exit_batch,
1506         .id             = &nfnl_queue_net_id,
1507         .size           = sizeof(struct nfnl_queue_net),
1508 };
1509
1510 static int __init nfnetlink_queue_init(void)
1511 {
1512         int status;
1513
1514         status = register_pernet_subsys(&nfnl_queue_net_ops);
1515         if (status < 0) {
1516                 pr_err("nf_queue: failed to register pernet ops\n");
1517                 goto out;
1518         }
1519
1520         netlink_register_notifier(&nfqnl_rtnl_notifier);
1521         status = nfnetlink_subsys_register(&nfqnl_subsys);
1522         if (status < 0) {
1523                 pr_err("nf_queue: failed to create netlink socket\n");
1524                 goto cleanup_netlink_notifier;
1525         }
1526
1527         status = register_netdevice_notifier(&nfqnl_dev_notifier);
1528         if (status < 0) {
1529                 pr_err("nf_queue: failed to register netdevice notifier\n");
1530                 goto cleanup_netlink_subsys;
1531         }
1532
1533         return status;
1534
1535 cleanup_netlink_subsys:
1536         nfnetlink_subsys_unregister(&nfqnl_subsys);
1537 cleanup_netlink_notifier:
1538         netlink_unregister_notifier(&nfqnl_rtnl_notifier);
1539         unregister_pernet_subsys(&nfnl_queue_net_ops);
1540 out:
1541         return status;
1542 }
1543
1544 static void __exit nfnetlink_queue_fini(void)
1545 {
1546         unregister_netdevice_notifier(&nfqnl_dev_notifier);
1547         nfnetlink_subsys_unregister(&nfqnl_subsys);
1548         netlink_unregister_notifier(&nfqnl_rtnl_notifier);
1549         unregister_pernet_subsys(&nfnl_queue_net_ops);
1550
1551         rcu_barrier(); /* Wait for completion of call_rcu()'s */
1552 }
1553
1554 MODULE_DESCRIPTION("netfilter packet queue handler");
1555 MODULE_AUTHOR("Harald Welte <laforge@netfilter.org>");
1556 MODULE_LICENSE("GPL");
1557 MODULE_ALIAS_NFNL_SUBSYS(NFNL_SUBSYS_QUEUE);
1558
1559 module_init(nfnetlink_queue_init);
1560 module_exit(nfnetlink_queue_fini);