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    ____cacheline_aligned_in_smp;
  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 unsigned 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)
 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                 goto nlmsg_failure;
 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                 goto nlmsg_failure;
 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) {
 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         if (seclen)
 602                 security_release_secctx(secdata, seclen);
 603         return skb;
 604
 605 nla_put_failure:
 606         skb_tx_error(entskb);
 607         kfree_skb(skb);
 608         net_err_ratelimited("nf_queue: error creating packet message\n");
 609 nlmsg_failure:
 610         if (seclen)
 611                 security_release_secctx(secdata, seclen);
 612         return NULL;
 613 }
 614
 615 static int
 616 __nfqnl_enqueue_packet(struct net *net, struct nfqnl_instance *queue,
 617                         struct nf_queue_entry *entry)
 618 {
 619         struct sk_buff *nskb;
 620         int err = -ENOBUFS;
 621         __be32 *packet_id_ptr;
 622         int failopen = 0;
 623
 624         nskb = nfqnl_build_packet_message(net, queue, entry, &packet_id_ptr);
 625         if (nskb == NULL) {
 626                 err = -ENOMEM;
 627                 goto err_out;
 628         }
 629         spin_lock_bh(&queue->lock);
 630
 631         if (queue->queue_total >= queue->queue_maxlen) {
 632                 if (queue->flags & NFQA_CFG_F_FAIL_OPEN) {
 633                         failopen = 1;
 634                         err = 0;
 635                 } else {
 636                         queue->queue_dropped++;
 637                         net_warn_ratelimited("nf_queue: full at %d entries, dropping packets(s)\n",
 638                                              queue->queue_total);
 639                 }
 640                 goto err_out_free_nskb;
 641         }
 642         entry->id = ++queue->id_sequence;
 643         *packet_id_ptr = htonl(entry->id);
 644
 645         /* nfnetlink_unicast will either free the nskb or add it to a socket */
 646         err = nfnetlink_unicast(nskb, net, queue->peer_portid, MSG_DONTWAIT);
 647         if (err < 0) {
 648                 if (queue->flags & NFQA_CFG_F_FAIL_OPEN) {
 649                         failopen = 1;
 650                         err = 0;
 651                 } else {
 652                         queue->queue_user_dropped++;
 653                 }
 654                 goto err_out_unlock;
 655         }
 656
 657         __enqueue_entry(queue, entry);
 658
 659         spin_unlock_bh(&queue->lock);
 660         return 0;
 661
 662 err_out_free_nskb:
 663         kfree_skb(nskb);
 664 err_out_unlock:
 665         spin_unlock_bh(&queue->lock);
 666         if (failopen)
 667                 nf_reinject(entry, NF_ACCEPT);
 668 err_out:
 669         return err;
 670 }
 671
 672 static struct nf_queue_entry *
 673 nf_queue_entry_dup(struct nf_queue_entry *e)
 674 {
 675         struct nf_queue_entry *entry = kmemdup(e, e->size, GFP_ATOMIC);
 676         if (entry)
 677                 nf_queue_entry_get_refs(entry);
 678         return entry;
 679 }
 680
 681 #if IS_ENABLED(CONFIG_BRIDGE_NETFILTER)
 682 /* When called from bridge netfilter, skb->data must point to MAC header
 683  * before calling skb_gso_segment(). Else, original MAC header is lost
 684  * and segmented skbs will be sent to wrong destination.
 685  */
 686 static void nf_bridge_adjust_skb_data(struct sk_buff *skb)
 687 {
 688         if (skb->nf_bridge)
 689                 __skb_push(skb, skb->network_header - skb->mac_header);
 690 }
 691
 692 static void nf_bridge_adjust_segmented_data(struct sk_buff *skb)
 693 {
 694         if (skb->nf_bridge)
 695                 __skb_pull(skb, skb->network_header - skb->mac_header);
 696 }
 697 #else
 698 #define nf_bridge_adjust_skb_data(s) do {} while (0)
 699 #define nf_bridge_adjust_segmented_data(s) do {} while (0)
 700 #endif
 701
 702 static void free_entry(struct nf_queue_entry *entry)
 703 {
 704         nf_queue_entry_release_refs(entry);
 705         kfree(entry);
 706 }
 707
 708 static int
 709 __nfqnl_enqueue_packet_gso(struct net *net, struct nfqnl_instance *queue,
 710                            struct sk_buff *skb, struct nf_queue_entry *entry)
 711 {
 712         int ret = -ENOMEM;
 713         struct nf_queue_entry *entry_seg;
 714
 715         nf_bridge_adjust_segmented_data(skb);
 716
 717         if (skb->next == NULL) { /* last packet, no need to copy entry */
 718                 struct sk_buff *gso_skb = entry->skb;
 719                 entry->skb = skb;
 720                 ret = __nfqnl_enqueue_packet(net, queue, entry);
 721                 if (ret)
 722                         entry->skb = gso_skb;
 723                 return ret;
 724         }
 725
 726         skb->next = NULL;
 727
 728         entry_seg = nf_queue_entry_dup(entry);
 729         if (entry_seg) {
 730                 entry_seg->skb = skb;
 731                 ret = __nfqnl_enqueue_packet(net, queue, entry_seg);
 732                 if (ret)
 733                         free_entry(entry_seg);
 734         }
 735         return ret;
 736 }
 737
 738 static int
 739 nfqnl_enqueue_packet(struct nf_queue_entry *entry, unsigned int queuenum)
 740 {
 741         unsigned int queued;
 742         struct nfqnl_instance *queue;
 743         struct sk_buff *skb, *segs;
 744         int err = -ENOBUFS;
 745         struct net *net = entry->state.net;
 746         struct nfnl_queue_net *q = nfnl_queue_pernet(net);
 747
 748         /* rcu_read_lock()ed by nf_hook_thresh */
 749         queue = instance_lookup(q, queuenum);
 750         if (!queue)
 751                 return -ESRCH;
 752
 753         if (queue->copy_mode == NFQNL_COPY_NONE)
 754                 return -EINVAL;
 755
 756         skb = entry->skb;
 757
 758         switch (entry->state.pf) {
 759         case NFPROTO_IPV4:
 760                 skb->protocol = htons(ETH_P_IP);
 761                 break;
 762         case NFPROTO_IPV6:
 763                 skb->protocol = htons(ETH_P_IPV6);
 764                 break;
 765         }
 766
 767         if ((queue->flags & NFQA_CFG_F_GSO) || !skb_is_gso(skb))
 768                 return __nfqnl_enqueue_packet(net, queue, entry);
 769
 770         nf_bridge_adjust_skb_data(skb);
 771         segs = skb_gso_segment(skb, 0);
 772         /* Does not use PTR_ERR to limit the number of error codes that can be
 773          * returned by nf_queue.  For instance, callers rely on -ESRCH to
 774          * mean 'ignore this hook'.
 775          */
 776         if (IS_ERR_OR_NULL(segs))
 777                 goto out_err;
 778         queued = 0;
 779         err = 0;
 780         do {
 781                 struct sk_buff *nskb = segs->next;
 782                 if (err == 0)
 783                         err = __nfqnl_enqueue_packet_gso(net, queue,
 784                                                         segs, entry);
 785                 if (err == 0)
 786                         queued++;
 787                 else
 788                         kfree_skb(segs);
 789                 segs = nskb;
 790         } while (segs);
 791
 792         if (queued) {
 793                 if (err) /* some segments are already queued */
 794                         free_entry(entry);
 795                 kfree_skb(skb);
 796                 return 0;
 797         }
 798  out_err:
 799         nf_bridge_adjust_segmented_data(skb);
 800         return err;
 801 }
 802
 803 static int
 804 nfqnl_mangle(void *data, int data_len, struct nf_queue_entry *e, int diff)
 805 {
 806         struct sk_buff *nskb;
 807
 808         if (diff < 0) {
 809                 if (pskb_trim(e->skb, data_len))
 810                         return -ENOMEM;
 811         } else if (diff > 0) {
 812                 if (data_len > 0xFFFF)
 813                         return -EINVAL;
 814                 if (diff > skb_tailroom(e->skb)) {
 815                         nskb = skb_copy_expand(e->skb, skb_headroom(e->skb),
 816                                                diff, GFP_ATOMIC);
 817                         if (!nskb) {
 818                                 printk(KERN_WARNING "nf_queue: OOM "
 819                                       "in mangle, dropping packet\n");
 820                                 return -ENOMEM;
 821                         }
 822                         kfree_skb(e->skb);
 823                         e->skb = nskb;
 824                 }
 825                 skb_put(e->skb, diff);
 826         }
 827         if (!skb_make_writable(e->skb, data_len))
 828                 return -ENOMEM;
 829         skb_copy_to_linear_data(e->skb, data, data_len);
 830         e->skb->ip_summed = CHECKSUM_NONE;
 831         return 0;
 832 }
 833
 834 static int
 835 nfqnl_set_mode(struct nfqnl_instance *queue,
 836                unsigned char mode, unsigned int range)
 837 {
 838         int status = 0;
 839
 840         spin_lock_bh(&queue->lock);
 841         switch (mode) {
 842         case NFQNL_COPY_NONE:
 843         case NFQNL_COPY_META:
 844                 queue->copy_mode = mode;
 845                 queue->copy_range = 0;
 846                 break;
 847
 848         case NFQNL_COPY_PACKET:
 849                 queue->copy_mode = mode;
 850                 if (range == 0 || range > NFQNL_MAX_COPY_RANGE)
 851                         queue->copy_range = NFQNL_MAX_COPY_RANGE;
 852                 else
 853                         queue->copy_range = range;
 854                 break;
 855
 856         default:
 857                 status = -EINVAL;
 858
 859         }
 860         spin_unlock_bh(&queue->lock);
 861
 862         return status;
 863 }
 864
 865 static int
 866 dev_cmp(struct nf_queue_entry *entry, unsigned long ifindex)
 867 {
 868         if (entry->state.in)
 869                 if (entry->state.in->ifindex == ifindex)
 870                         return 1;
 871         if (entry->state.out)
 872                 if (entry->state.out->ifindex == ifindex)
 873                         return 1;
 874 #if IS_ENABLED(CONFIG_BRIDGE_NETFILTER)
 875         if (entry->skb->nf_bridge) {
 876                 int physinif, physoutif;
 877
 878                 physinif = nf_bridge_get_physinif(entry->skb);
 879                 physoutif = nf_bridge_get_physoutif(entry->skb);
 880
 881                 if (physinif == ifindex || physoutif == ifindex)
 882                         return 1;
 883         }
 884 #endif
 885         return 0;
 886 }
 887
 888 /* drop all packets with either indev or outdev == ifindex from all queue
 889  * instances */
 890 static void
 891 nfqnl_dev_drop(struct net *net, int ifindex)
 892 {
 893         int i;
 894         struct nfnl_queue_net *q = nfnl_queue_pernet(net);
 895
 896         rcu_read_lock();
 897
 898         for (i = 0; i < INSTANCE_BUCKETS; i++) {
 899                 struct nfqnl_instance *inst;
 900                 struct hlist_head *head = &q->instance_table[i];
 901
 902                 hlist_for_each_entry_rcu(inst, head, hlist)
 903                         nfqnl_flush(inst, dev_cmp, ifindex);
 904         }
 905
 906         rcu_read_unlock();
 907 }
 908
 909 static int
 910 nfqnl_rcv_dev_event(struct notifier_block *this,
 911                     unsigned long event, void *ptr)
 912 {
 913         struct net_device *dev = netdev_notifier_info_to_dev(ptr);
 914
 915         /* Drop any packets associated with the downed device */
 916         if (event == NETDEV_DOWN)
 917                 nfqnl_dev_drop(dev_net(dev), dev->ifindex);
 918         return NOTIFY_DONE;
 919 }
 920
 921 static struct notifier_block nfqnl_dev_notifier = {
 922         .notifier_call  = nfqnl_rcv_dev_event,
 923 };
 924
 925 static int nf_hook_cmp(struct nf_queue_entry *entry, unsigned long entry_ptr)
 926 {
 927         return rcu_access_pointer(entry->hook) ==
 928                 (struct nf_hook_entry *)entry_ptr;
 929 }
 930
 931 static void nfqnl_nf_hook_drop(struct net *net,
 932                                const struct nf_hook_entry *hook)
 933 {
 934         struct nfnl_queue_net *q = nfnl_queue_pernet(net);
 935         int i;
 936
 937         rcu_read_lock();
 938         for (i = 0; i < INSTANCE_BUCKETS; i++) {
 939                 struct nfqnl_instance *inst;
 940                 struct hlist_head *head = &q->instance_table[i];
 941
 942                 hlist_for_each_entry_rcu(inst, head, hlist)
 943                         nfqnl_flush(inst, nf_hook_cmp, (unsigned long)hook);
 944         }
 945         rcu_read_unlock();
 946 }
 947
 948 static int
 949 nfqnl_rcv_nl_event(struct notifier_block *this,
 950                    unsigned long event, void *ptr)
 951 {
 952         struct netlink_notify *n = ptr;
 953         struct nfnl_queue_net *q = nfnl_queue_pernet(n->net);
 954
 955         if (event == NETLINK_URELEASE && n->protocol == NETLINK_NETFILTER) {
 956                 int i;
 957
 958                 /* destroy all instances for this portid */
 959                 spin_lock(&q->instances_lock);
 960                 for (i = 0; i < INSTANCE_BUCKETS; i++) {
 961                         struct hlist_node *t2;
 962                         struct nfqnl_instance *inst;
 963                         struct hlist_head *head = &q->instance_table[i];
 964
 965                         hlist_for_each_entry_safe(inst, t2, head, hlist) {
 966                                 if (n->portid == inst->peer_portid)
 967                                         __instance_destroy(inst);
 968                         }
 969                 }
 970                 spin_unlock(&q->instances_lock);
 971         }
 972         return NOTIFY_DONE;
 973 }
 974
 975 static struct notifier_block nfqnl_rtnl_notifier = {
 976         .notifier_call  = nfqnl_rcv_nl_event,
 977 };
 978
 979 static const struct nla_policy nfqa_vlan_policy[NFQA_VLAN_MAX + 1] = {
 980         [NFQA_VLAN_TCI]         = { .type = NLA_U16},
 981         [NFQA_VLAN_PROTO]       = { .type = NLA_U16},
 982 };
 983
 984 static const struct nla_policy nfqa_verdict_policy[NFQA_MAX+1] = {
 985         [NFQA_VERDICT_HDR]      = { .len = sizeof(struct nfqnl_msg_verdict_hdr) },
 986         [NFQA_MARK]             = { .type = NLA_U32 },
 987         [NFQA_PAYLOAD]          = { .type = NLA_UNSPEC },
 988         [NFQA_CT]               = { .type = NLA_UNSPEC },
 989         [NFQA_EXP]              = { .type = NLA_UNSPEC },
 990         [NFQA_VLAN]             = { .type = NLA_NESTED },
 991 };
 992
 993 static const struct nla_policy nfqa_verdict_batch_policy[NFQA_MAX+1] = {
 994         [NFQA_VERDICT_HDR]      = { .len = sizeof(struct nfqnl_msg_verdict_hdr) },
 995         [NFQA_MARK]             = { .type = NLA_U32 },
 996 };
 997
 998 static struct nfqnl_instance *
 999 verdict_instance_lookup(struct nfnl_queue_net *q, u16 queue_num, u32 nlportid)
1000 {
1001         struct nfqnl_instance *queue;
1002
1003         queue = instance_lookup(q, queue_num);
1004         if (!queue)
1005                 return ERR_PTR(-ENODEV);
1006
1007         if (queue->peer_portid != nlportid)
1008                 return ERR_PTR(-EPERM);
1009
1010         return queue;
1011 }
1012
1013 static struct nfqnl_msg_verdict_hdr*
1014 verdicthdr_get(const struct nlattr * const nfqa[])
1015 {
1016         struct nfqnl_msg_verdict_hdr *vhdr;
1017         unsigned int verdict;
1018
1019         if (!nfqa[NFQA_VERDICT_HDR])
1020                 return NULL;
1021
1022         vhdr = nla_data(nfqa[NFQA_VERDICT_HDR]);
1023         verdict = ntohl(vhdr->verdict) & NF_VERDICT_MASK;
1024         if (verdict > NF_MAX_VERDICT || verdict == NF_STOLEN)
1025                 return NULL;
1026         return vhdr;
1027 }
1028
1029 static int nfq_id_after(unsigned int id, unsigned int max)
1030 {
1031         return (int)(id - max) > 0;
1032 }
1033
1034 static int nfqnl_recv_verdict_batch(struct net *net, struct sock *ctnl,
1035                                     struct sk_buff *skb,
1036                                     const struct nlmsghdr *nlh,
1037                                     const struct nlattr * const nfqa[])
1038 {
1039         struct nfgenmsg *nfmsg = nlmsg_data(nlh);
1040         struct nf_queue_entry *entry, *tmp;
1041         unsigned int verdict, maxid;
1042         struct nfqnl_msg_verdict_hdr *vhdr;
1043         struct nfqnl_instance *queue;
1044         LIST_HEAD(batch_list);
1045         u16 queue_num = ntohs(nfmsg->res_id);
1046         struct nfnl_queue_net *q = nfnl_queue_pernet(net);
1047
1048         queue = verdict_instance_lookup(q, queue_num,
1049                                         NETLINK_CB(skb).portid);
1050         if (IS_ERR(queue))
1051                 return PTR_ERR(queue);
1052
1053         vhdr = verdicthdr_get(nfqa);
1054         if (!vhdr)
1055                 return -EINVAL;
1056
1057         verdict = ntohl(vhdr->verdict);
1058         maxid = ntohl(vhdr->id);
1059
1060         spin_lock_bh(&queue->lock);
1061
1062         list_for_each_entry_safe(entry, tmp, &queue->queue_list, list) {
1063                 if (nfq_id_after(entry->id, maxid))
1064                         break;
1065                 __dequeue_entry(queue, entry);
1066                 list_add_tail(&entry->list, &batch_list);
1067         }
1068
1069         spin_unlock_bh(&queue->lock);
1070
1071         if (list_empty(&batch_list))
1072                 return -ENOENT;
1073
1074         list_for_each_entry_safe(entry, tmp, &batch_list, list) {
1075                 if (nfqa[NFQA_MARK])
1076                         entry->skb->mark = ntohl(nla_get_be32(nfqa[NFQA_MARK]));
1077                 nf_reinject(entry, verdict);
1078         }
1079         return 0;
1080 }
1081
1082 static struct nf_conn *nfqnl_ct_parse(struct nfnl_ct_hook *nfnl_ct,
1083                                       const struct nlmsghdr *nlh,
1084                                       const struct nlattr * const nfqa[],
1085                                       struct nf_queue_entry *entry,
1086                                       enum ip_conntrack_info *ctinfo)
1087 {
1088         struct nf_conn *ct;
1089
1090         ct = nfnl_ct->get_ct(entry->skb, ctinfo);
1091         if (ct == NULL)
1092                 return NULL;
1093
1094         if (nfnl_ct->parse(nfqa[NFQA_CT], ct) < 0)
1095                 return NULL;
1096
1097         if (nfqa[NFQA_EXP])
1098                 nfnl_ct->attach_expect(nfqa[NFQA_EXP], ct,
1099                                       NETLINK_CB(entry->skb).portid,
1100                                       nlmsg_report(nlh));
1101         return ct;
1102 }
1103
1104 static int nfqa_parse_bridge(struct nf_queue_entry *entry,
1105                              const struct nlattr * const nfqa[])
1106 {
1107         if (nfqa[NFQA_VLAN]) {
1108                 struct nlattr *tb[NFQA_VLAN_MAX + 1];
1109                 int err;
1110
1111                 err = nla_parse_nested(tb, NFQA_VLAN_MAX, nfqa[NFQA_VLAN],
1112                                        nfqa_vlan_policy);
1113                 if (err < 0)
1114                         return err;
1115
1116                 if (!tb[NFQA_VLAN_TCI] || !tb[NFQA_VLAN_PROTO])
1117                         return -EINVAL;
1118
1119                 entry->skb->vlan_tci = ntohs(nla_get_be16(tb[NFQA_VLAN_TCI]));
1120                 entry->skb->vlan_proto = nla_get_be16(tb[NFQA_VLAN_PROTO]);
1121         }
1122
1123         if (nfqa[NFQA_L2HDR]) {
1124                 int mac_header_len = entry->skb->network_header -
1125                         entry->skb->mac_header;
1126
1127                 if (mac_header_len != nla_len(nfqa[NFQA_L2HDR]))
1128                         return -EINVAL;
1129                 else if (mac_header_len > 0)
1130                         memcpy(skb_mac_header(entry->skb),
1131                                nla_data(nfqa[NFQA_L2HDR]),
1132                                mac_header_len);
1133         }
1134
1135         return 0;
1136 }
1137
1138 static int nfqnl_recv_verdict(struct net *net, struct sock *ctnl,
1139                               struct sk_buff *skb,
1140                               const struct nlmsghdr *nlh,
1141                               const struct nlattr * const nfqa[])
1142 {
1143         struct nfgenmsg *nfmsg = nlmsg_data(nlh);
1144         u_int16_t queue_num = ntohs(nfmsg->res_id);
1145         struct nfqnl_msg_verdict_hdr *vhdr;
1146         struct nfqnl_instance *queue;
1147         unsigned int verdict;
1148         struct nf_queue_entry *entry;
1149         enum ip_conntrack_info uninitialized_var(ctinfo);
1150         struct nfnl_ct_hook *nfnl_ct;
1151         struct nf_conn *ct = NULL;
1152         struct nfnl_queue_net *q = nfnl_queue_pernet(net);
1153         int err;
1154
1155         queue = verdict_instance_lookup(q, queue_num,
1156                                         NETLINK_CB(skb).portid);
1157         if (IS_ERR(queue))
1158                 return PTR_ERR(queue);
1159
1160         vhdr = verdicthdr_get(nfqa);
1161         if (!vhdr)
1162                 return -EINVAL;
1163
1164         verdict = ntohl(vhdr->verdict);
1165
1166         entry = find_dequeue_entry(queue, ntohl(vhdr->id));
1167         if (entry == NULL)
1168                 return -ENOENT;
1169
1170         /* rcu lock already held from nfnl->call_rcu. */
1171         nfnl_ct = rcu_dereference(nfnl_ct_hook);
1172
1173         if (nfqa[NFQA_CT]) {
1174                 if (nfnl_ct != NULL)
1175                         ct = nfqnl_ct_parse(nfnl_ct, nlh, nfqa, entry, &ctinfo);
1176         }
1177
1178         if (entry->state.pf == PF_BRIDGE) {
1179                 err = nfqa_parse_bridge(entry, nfqa);
1180                 if (err < 0)
1181                         return err;
1182         }
1183
1184         if (nfqa[NFQA_PAYLOAD]) {
1185                 u16 payload_len = nla_len(nfqa[NFQA_PAYLOAD]);
1186                 int diff = payload_len - entry->skb->len;
1187
1188                 if (nfqnl_mangle(nla_data(nfqa[NFQA_PAYLOAD]),
1189                                  payload_len, entry, diff) < 0)
1190                         verdict = NF_DROP;
1191
1192                 if (ct && diff)
1193                         nfnl_ct->seq_adjust(entry->skb, ct, ctinfo, diff);
1194         }
1195
1196         if (nfqa[NFQA_MARK])
1197                 entry->skb->mark = ntohl(nla_get_be32(nfqa[NFQA_MARK]));
1198
1199         nf_reinject(entry, verdict);
1200         return 0;
1201 }
1202
1203 static int nfqnl_recv_unsupp(struct net *net, struct sock *ctnl,
1204                              struct sk_buff *skb, const struct nlmsghdr *nlh,
1205                              const struct nlattr * const nfqa[])
1206 {
1207         return -ENOTSUPP;
1208 }
1209
1210 static const struct nla_policy nfqa_cfg_policy[NFQA_CFG_MAX+1] = {
1211         [NFQA_CFG_CMD]          = { .len = sizeof(struct nfqnl_msg_config_cmd) },
1212         [NFQA_CFG_PARAMS]       = { .len = sizeof(struct nfqnl_msg_config_params) },
1213 };
1214
1215 static const struct nf_queue_handler nfqh = {
1216         .outfn          = &nfqnl_enqueue_packet,
1217         .nf_hook_drop   = &nfqnl_nf_hook_drop,
1218 };
1219
1220 static int nfqnl_recv_config(struct net *net, struct sock *ctnl,
1221                              struct sk_buff *skb, const struct nlmsghdr *nlh,
1222                              const struct nlattr * const nfqa[])
1223 {
1224         struct nfgenmsg *nfmsg = nlmsg_data(nlh);
1225         u_int16_t queue_num = ntohs(nfmsg->res_id);
1226         struct nfqnl_instance *queue;
1227         struct nfqnl_msg_config_cmd *cmd = NULL;
1228         struct nfnl_queue_net *q = nfnl_queue_pernet(net);
1229         __u32 flags = 0, mask = 0;
1230         int ret = 0;
1231
1232         if (nfqa[NFQA_CFG_CMD]) {
1233                 cmd = nla_data(nfqa[NFQA_CFG_CMD]);
1234
1235                 /* Obsolete commands without queue context */
1236                 switch (cmd->command) {
1237                 case NFQNL_CFG_CMD_PF_BIND: return 0;
1238                 case NFQNL_CFG_CMD_PF_UNBIND: return 0;
1239                 }
1240         }
1241
1242         /* Check if we support these flags in first place, dependencies should
1243          * be there too not to break atomicity.
1244          */
1245         if (nfqa[NFQA_CFG_FLAGS]) {
1246                 if (!nfqa[NFQA_CFG_MASK]) {
1247                         /* A mask is needed to specify which flags are being
1248                          * changed.
1249                          */
1250                         return -EINVAL;
1251                 }
1252
1253                 flags = ntohl(nla_get_be32(nfqa[NFQA_CFG_FLAGS]));
1254                 mask = ntohl(nla_get_be32(nfqa[NFQA_CFG_MASK]));
1255
1256                 if (flags >= NFQA_CFG_F_MAX)
1257                         return -EOPNOTSUPP;
1258
1259 #if !IS_ENABLED(CONFIG_NETWORK_SECMARK)
1260                 if (flags & mask & NFQA_CFG_F_SECCTX)
1261                         return -EOPNOTSUPP;
1262 #endif
1263                 if ((flags & mask & NFQA_CFG_F_CONNTRACK) &&
1264                     !rcu_access_pointer(nfnl_ct_hook)) {
1265 #ifdef CONFIG_MODULES
1266                         nfnl_unlock(NFNL_SUBSYS_QUEUE);
1267                         request_module("ip_conntrack_netlink");
1268                         nfnl_lock(NFNL_SUBSYS_QUEUE);
1269                         if (rcu_access_pointer(nfnl_ct_hook))
1270                                 return -EAGAIN;
1271 #endif
1272                         return -EOPNOTSUPP;
1273                 }
1274         }
1275
1276         rcu_read_lock();
1277         queue = instance_lookup(q, queue_num);
1278         if (queue && queue->peer_portid != NETLINK_CB(skb).portid) {
1279                 ret = -EPERM;
1280                 goto err_out_unlock;
1281         }
1282
1283         if (cmd != NULL) {
1284                 switch (cmd->command) {
1285                 case NFQNL_CFG_CMD_BIND:
1286                         if (queue) {
1287                                 ret = -EBUSY;
1288                                 goto err_out_unlock;
1289                         }
1290                         queue = instance_create(q, queue_num,
1291                                                 NETLINK_CB(skb).portid);
1292                         if (IS_ERR(queue)) {
1293                                 ret = PTR_ERR(queue);
1294                                 goto err_out_unlock;
1295                         }
1296                         break;
1297                 case NFQNL_CFG_CMD_UNBIND:
1298                         if (!queue) {
1299                                 ret = -ENODEV;
1300                                 goto err_out_unlock;
1301                         }
1302                         instance_destroy(q, queue);
1303                         goto err_out_unlock;
1304                 case NFQNL_CFG_CMD_PF_BIND:
1305                 case NFQNL_CFG_CMD_PF_UNBIND:
1306                         break;
1307                 default:
1308                         ret = -ENOTSUPP;
1309                         goto err_out_unlock;
1310                 }
1311         }
1312
1313         if (!queue) {
1314                 ret = -ENODEV;
1315                 goto err_out_unlock;
1316         }
1317
1318         if (nfqa[NFQA_CFG_PARAMS]) {
1319                 struct nfqnl_msg_config_params *params =
1320                         nla_data(nfqa[NFQA_CFG_PARAMS]);
1321
1322                 nfqnl_set_mode(queue, params->copy_mode,
1323                                 ntohl(params->copy_range));
1324         }
1325
1326         if (nfqa[NFQA_CFG_QUEUE_MAXLEN]) {
1327                 __be32 *queue_maxlen = nla_data(nfqa[NFQA_CFG_QUEUE_MAXLEN]);
1328
1329                 spin_lock_bh(&queue->lock);
1330                 queue->queue_maxlen = ntohl(*queue_maxlen);
1331                 spin_unlock_bh(&queue->lock);
1332         }
1333
1334         if (nfqa[NFQA_CFG_FLAGS]) {
1335                 spin_lock_bh(&queue->lock);
1336                 queue->flags &= ~mask;
1337                 queue->flags |= flags & mask;
1338                 spin_unlock_bh(&queue->lock);
1339         }
1340
1341 err_out_unlock:
1342         rcu_read_unlock();
1343         return ret;
1344 }
1345
1346 static const struct nfnl_callback nfqnl_cb[NFQNL_MSG_MAX] = {
1347         [NFQNL_MSG_PACKET]      = { .call_rcu = nfqnl_recv_unsupp,
1348                                     .attr_count = NFQA_MAX, },
1349         [NFQNL_MSG_VERDICT]     = { .call_rcu = nfqnl_recv_verdict,
1350                                     .attr_count = NFQA_MAX,
1351                                     .policy = nfqa_verdict_policy },
1352         [NFQNL_MSG_CONFIG]      = { .call = nfqnl_recv_config,
1353                                     .attr_count = NFQA_CFG_MAX,
1354                                     .policy = nfqa_cfg_policy },
1355         [NFQNL_MSG_VERDICT_BATCH]={ .call_rcu = nfqnl_recv_verdict_batch,
1356                                     .attr_count = NFQA_MAX,
1357                                     .policy = nfqa_verdict_batch_policy },
1358 };
1359
1360 static const struct nfnetlink_subsystem nfqnl_subsys = {
1361         .name           = "nf_queue",
1362         .subsys_id      = NFNL_SUBSYS_QUEUE,
1363         .cb_count       = NFQNL_MSG_MAX,
1364         .cb             = nfqnl_cb,
1365 };
1366
1367 #ifdef CONFIG_PROC_FS
1368 struct iter_state {
1369         struct seq_net_private p;
1370         unsigned int bucket;
1371 };
1372
1373 static struct hlist_node *get_first(struct seq_file *seq)
1374 {
1375         struct iter_state *st = seq->private;
1376         struct net *net;
1377         struct nfnl_queue_net *q;
1378
1379         if (!st)
1380                 return NULL;
1381
1382         net = seq_file_net(seq);
1383         q = nfnl_queue_pernet(net);
1384         for (st->bucket = 0; st->bucket < INSTANCE_BUCKETS; st->bucket++) {
1385                 if (!hlist_empty(&q->instance_table[st->bucket]))
1386                         return q->instance_table[st->bucket].first;
1387         }
1388         return NULL;
1389 }
1390
1391 static struct hlist_node *get_next(struct seq_file *seq, struct hlist_node *h)
1392 {
1393         struct iter_state *st = seq->private;
1394         struct net *net = seq_file_net(seq);
1395
1396         h = h->next;
1397         while (!h) {
1398                 struct nfnl_queue_net *q;
1399
1400                 if (++st->bucket >= INSTANCE_BUCKETS)
1401                         return NULL;
1402
1403                 q = nfnl_queue_pernet(net);
1404                 h = q->instance_table[st->bucket].first;
1405         }
1406         return h;
1407 }
1408
1409 static struct hlist_node *get_idx(struct seq_file *seq, loff_t pos)
1410 {
1411         struct hlist_node *head;
1412         head = get_first(seq);
1413
1414         if (head)
1415                 while (pos && (head = get_next(seq, head)))
1416                         pos--;
1417         return pos ? NULL : head;
1418 }
1419
1420 static void *seq_start(struct seq_file *s, loff_t *pos)
1421         __acquires(nfnl_queue_pernet(seq_file_net(s))->instances_lock)
1422 {
1423         spin_lock(&nfnl_queue_pernet(seq_file_net(s))->instances_lock);
1424         return get_idx(s, *pos);
1425 }
1426
1427 static void *seq_next(struct seq_file *s, void *v, loff_t *pos)
1428 {
1429         (*pos)++;
1430         return get_next(s, v);
1431 }
1432
1433 static void seq_stop(struct seq_file *s, void *v)
1434         __releases(nfnl_queue_pernet(seq_file_net(s))->instances_lock)
1435 {
1436         spin_unlock(&nfnl_queue_pernet(seq_file_net(s))->instances_lock);
1437 }
1438
1439 static int seq_show(struct seq_file *s, void *v)
1440 {
1441         const struct nfqnl_instance *inst = v;
1442
1443         seq_printf(s, "%5u %6u %5u %1u %5u %5u %5u %8u %2d\n",
1444                    inst->queue_num,
1445                    inst->peer_portid, inst->queue_total,
1446                    inst->copy_mode, inst->copy_range,
1447                    inst->queue_dropped, inst->queue_user_dropped,
1448                    inst->id_sequence, 1);
1449         return 0;
1450 }
1451
1452 static const struct seq_operations nfqnl_seq_ops = {
1453         .start  = seq_start,
1454         .next   = seq_next,
1455         .stop   = seq_stop,
1456         .show   = seq_show,
1457 };
1458
1459 static int nfqnl_open(struct inode *inode, struct file *file)
1460 {
1461         return seq_open_net(inode, file, &nfqnl_seq_ops,
1462                         sizeof(struct iter_state));
1463 }
1464
1465 static const struct file_operations nfqnl_file_ops = {
1466         .owner   = THIS_MODULE,
1467         .open    = nfqnl_open,
1468         .read    = seq_read,
1469         .llseek  = seq_lseek,
1470         .release = seq_release_net,
1471 };
1472
1473 #endif /* PROC_FS */
1474
1475 static int __net_init nfnl_queue_net_init(struct net *net)
1476 {
1477         unsigned int i;
1478         struct nfnl_queue_net *q = nfnl_queue_pernet(net);
1479
1480         for (i = 0; i < INSTANCE_BUCKETS; i++)
1481                 INIT_HLIST_HEAD(&q->instance_table[i]);
1482
1483         spin_lock_init(&q->instances_lock);
1484
1485 #ifdef CONFIG_PROC_FS
1486         if (!proc_create("nfnetlink_queue", 0440,
1487                          net->nf.proc_netfilter, &nfqnl_file_ops))
1488                 return -ENOMEM;
1489 #endif
1490         nf_register_queue_handler(net, &nfqh);
1491         return 0;
1492 }
1493
1494 static void __net_exit nfnl_queue_net_exit(struct net *net)
1495 {
1496         nf_unregister_queue_handler(net);
1497 #ifdef CONFIG_PROC_FS
1498         remove_proc_entry("nfnetlink_queue", net->nf.proc_netfilter);
1499 #endif
1500 }
1501
1502 static void nfnl_queue_net_exit_batch(struct list_head *net_exit_list)
1503 {
1504         synchronize_rcu();
1505 }
1506
1507 static struct pernet_operations nfnl_queue_net_ops = {
1508         .init           = nfnl_queue_net_init,
1509         .exit           = nfnl_queue_net_exit,
1510         .exit_batch     = nfnl_queue_net_exit_batch,
1511         .id             = &nfnl_queue_net_id,
1512         .size           = sizeof(struct nfnl_queue_net),
1513 };
1514
1515 static int __init nfnetlink_queue_init(void)
1516 {
1517         int status;
1518
1519         status = register_pernet_subsys(&nfnl_queue_net_ops);
1520         if (status < 0) {
1521                 pr_err("nf_queue: failed to register pernet ops\n");
1522                 goto out;
1523         }
1524
1525         netlink_register_notifier(&nfqnl_rtnl_notifier);
1526         status = nfnetlink_subsys_register(&nfqnl_subsys);
1527         if (status < 0) {
1528                 pr_err("nf_queue: failed to create netlink socket\n");
1529                 goto cleanup_netlink_notifier;
1530         }
1531
1532         status = register_netdevice_notifier(&nfqnl_dev_notifier);
1533         if (status < 0) {
1534                 pr_err("nf_queue: failed to register netdevice notifier\n");
1535                 goto cleanup_netlink_subsys;
1536         }
1537
1538         return status;
1539
1540 cleanup_netlink_subsys:
1541         nfnetlink_subsys_unregister(&nfqnl_subsys);
1542 cleanup_netlink_notifier:
1543         netlink_unregister_notifier(&nfqnl_rtnl_notifier);
1544         unregister_pernet_subsys(&nfnl_queue_net_ops);
1545 out:
1546         return status;
1547 }
1548
1549 static void __exit nfnetlink_queue_fini(void)
1550 {
1551         unregister_netdevice_notifier(&nfqnl_dev_notifier);
1552         nfnetlink_subsys_unregister(&nfqnl_subsys);
1553         netlink_unregister_notifier(&nfqnl_rtnl_notifier);
1554         unregister_pernet_subsys(&nfnl_queue_net_ops);
1555
1556         rcu_barrier(); /* Wait for completion of call_rcu()'s */
1557 }
1558
1559 MODULE_DESCRIPTION("netfilter packet queue handler");
1560 MODULE_AUTHOR("Harald Welte <laforge@netfilter.org>");
1561 MODULE_LICENSE("GPL");
1562 MODULE_ALIAS_NFNL_SUBSYS(NFNL_SUBSYS_QUEUE);
1563
1564 module_init(nfnetlink_queue_init);
1565 module_exit(nfnetlink_queue_fini);