netfilter/nfnetlink_queue.c

   1 // SPDX-License-Identifier: GPL-2.0-only
   2 /*
   3  * This is a module which is used for queueing packets and communicating with
   4  * userspace via nfnetlink.
   5  *
   6  * (C) 2005 by Harald Welte <laforge@netfilter.org>
   7  * (C) 2007 by Patrick McHardy <kaber@trash.net>
   8  *
   9  * Based on the old ipv4-only ip_queue.c:
  10  * (C) 2000-2002 James Morris <jmorris@intercode.com.au>
  11  * (C) 2003-2005 Netfilter Core Team <coreteam@netfilter.org>
  12  */
  13
  14 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
  15
  16 #include <linux/module.h>
  17 #include <linux/skbuff.h>
  18 #include <linux/init.h>
  19 #include <linux/spinlock.h>
  20 #include <linux/slab.h>
  21 #include <linux/notifier.h>
  22 #include <linux/netdevice.h>
  23 #include <linux/netfilter.h>
  24 #include <linux/proc_fs.h>
  25 #include <linux/netfilter_ipv4.h>
  26 #include <linux/netfilter_ipv6.h>
  27 #include <linux/netfilter_bridge.h>
  28 #include <linux/netfilter/nfnetlink.h>
  29 #include <linux/netfilter/nfnetlink_queue.h>
  30 #include <linux/netfilter/nf_conntrack_common.h>
  31 #include <linux/list.h>
  32 #include <linux/cgroup-defs.h>
  33 #include <net/gso.h>
  34 #include <net/sock.h>
  35 #include <net/tcp_states.h>
  36 #include <net/netfilter/nf_queue.h>
  37 #include <net/netns/generic.h>
  38
  39 #include <linux/atomic.h>
  40
  41 #if IS_ENABLED(CONFIG_BRIDGE_NETFILTER)
  42 #include "../bridge/br_private.h"
  43 #endif
  44
  45 #if IS_ENABLED(CONFIG_NF_CONNTRACK)
  46 #include <net/netfilter/nf_conntrack.h>
  47 #endif
  48
  49 #define NFQNL_QMAX_DEFAULT 1024
  50
  51 /* We're using struct nlattr which has 16bit nla_len. Note that nla_len
  52  * includes the header length. Thus, the maximum packet length that we
  53  * support is 65531 bytes. We send truncated packets if the specified length
  54  * is larger than that.  Userspace can check for presence of NFQA_CAP_LEN
  55  * attribute to detect truncation.
  56  */
  57 #define NFQNL_MAX_COPY_RANGE (0xffff - NLA_HDRLEN)
  58
  59 struct nfqnl_instance {
  60         struct hlist_node hlist;                /* global list of queues */
  61         struct rcu_head rcu;
  62
  63         u32 peer_portid;
  64         unsigned int queue_maxlen;
  65         unsigned int copy_range;
  66         unsigned int queue_dropped;
  67         unsigned int queue_user_dropped;
  68
  69
  70         u_int16_t queue_num;                    /* number of this queue */
  71         u_int8_t copy_mode;
  72         u_int32_t flags;                        /* Set using NFQA_CFG_FLAGS */
  73 /*
  74  * Following fields are dirtied for each queued packet,
  75  * keep them in same cache line if possible.
  76  */
  77         spinlock_t      lock    ____cacheline_aligned_in_smp;
  78         unsigned int    queue_total;
  79         unsigned int    id_sequence;            /* 'sequence' of pkt ids */
  80         struct list_head queue_list;            /* packets in queue */
  81 };
  82
  83 typedef int (*nfqnl_cmpfn)(struct nf_queue_entry *, unsigned long);
  84
  85 static unsigned int nfnl_queue_net_id __read_mostly;
  86
  87 #define INSTANCE_BUCKETS        16
  88 struct nfnl_queue_net {
  89         spinlock_t instances_lock;
  90         struct hlist_head instance_table[INSTANCE_BUCKETS];
  91 };
  92
  93 static struct nfnl_queue_net *nfnl_queue_pernet(struct net *net)
  94 {
  95         return net_generic(net, nfnl_queue_net_id);
  96 }
  97
  98 static inline u_int8_t instance_hashfn(u_int16_t queue_num)
  99 {
 100         return ((queue_num >> 8) ^ queue_num) % INSTANCE_BUCKETS;
 101 }
 102
 103 static struct nfqnl_instance *
 104 instance_lookup(struct nfnl_queue_net *q, u_int16_t queue_num)
 105 {
 106         struct hlist_head *head;
 107         struct nfqnl_instance *inst;
 108
 109         head = &q->instance_table[instance_hashfn(queue_num)];
 110         hlist_for_each_entry_rcu(inst, head, hlist) {
 111                 if (inst->queue_num == queue_num)
 112                         return inst;
 113         }
 114         return NULL;
 115 }
 116
 117 static struct nfqnl_instance *
 118 instance_create(struct nfnl_queue_net *q, u_int16_t queue_num, u32 portid)
 119 {
 120         struct nfqnl_instance *inst;
 121         unsigned int h;
 122         int err;
 123
 124         spin_lock(&q->instances_lock);
 125         if (instance_lookup(q, queue_num)) {
 126                 err = -EEXIST;
 127                 goto out_unlock;
 128         }
 129
 130         inst = kzalloc(sizeof(*inst), GFP_ATOMIC);
 131         if (!inst) {
 132                 err = -ENOMEM;
 133                 goto out_unlock;
 134         }
 135
 136         inst->queue_num = queue_num;
 137         inst->peer_portid = portid;
 138         inst->queue_maxlen = NFQNL_QMAX_DEFAULT;
 139         inst->copy_range = NFQNL_MAX_COPY_RANGE;
 140         inst->copy_mode = NFQNL_COPY_NONE;
 141         spin_lock_init(&inst->lock);
 142         INIT_LIST_HEAD(&inst->queue_list);
 143
 144         if (!try_module_get(THIS_MODULE)) {
 145                 err = -EAGAIN;
 146                 goto out_free;
 147         }
 148
 149         h = instance_hashfn(queue_num);
 150         hlist_add_head_rcu(&inst->hlist, &q->instance_table[h]);
 151
 152         spin_unlock(&q->instances_lock);
 153
 154         return inst;
 155
 156 out_free:
 157         kfree(inst);
 158 out_unlock:
 159         spin_unlock(&q->instances_lock);
 160         return ERR_PTR(err);
 161 }
 162
 163 static void nfqnl_flush(struct nfqnl_instance *queue, nfqnl_cmpfn cmpfn,
 164                         unsigned long data);
 165
 166 static void
 167 instance_destroy_rcu(struct rcu_head *head)
 168 {
 169         struct nfqnl_instance *inst = container_of(head, struct nfqnl_instance,
 170                                                    rcu);
 171
 172         nfqnl_flush(inst, NULL, 0);
 173         kfree(inst);
 174         module_put(THIS_MODULE);
 175 }
 176
 177 static void
 178 __instance_destroy(struct nfqnl_instance *inst)
 179 {
 180         hlist_del_rcu(&inst->hlist);
 181         call_rcu(&inst->rcu, instance_destroy_rcu);
 182 }
 183
 184 static void
 185 instance_destroy(struct nfnl_queue_net *q, struct nfqnl_instance *inst)
 186 {
 187         spin_lock(&q->instances_lock);
 188         __instance_destroy(inst);
 189         spin_unlock(&q->instances_lock);
 190 }
 191
 192 static inline void
 193 __enqueue_entry(struct nfqnl_instance *queue, struct nf_queue_entry *entry)
 194 {
 195        list_add_tail(&entry->list, &queue->queue_list);
 196        queue->queue_total++;
 197 }
 198
 199 static void
 200 __dequeue_entry(struct nfqnl_instance *queue, struct nf_queue_entry *entry)
 201 {
 202         list_del(&entry->list);
 203         queue->queue_total--;
 204 }
 205
 206 static struct nf_queue_entry *
 207 find_dequeue_entry(struct nfqnl_instance *queue, unsigned int id)
 208 {
 209         struct nf_queue_entry *entry = NULL, *i;
 210
 211         spin_lock_bh(&queue->lock);
 212
 213         list_for_each_entry(i, &queue->queue_list, list) {
 214                 if (i->id == id) {
 215                         entry = i;
 216                         break;
 217                 }
 218         }
 219
 220         if (entry)
 221                 __dequeue_entry(queue, entry);
 222
 223         spin_unlock_bh(&queue->lock);
 224
 225         return entry;
 226 }
 227
 228 static void nfqnl_reinject(struct nf_queue_entry *entry, unsigned int verdict)
 229 {
 230         const struct nf_ct_hook *ct_hook;
 231
 232         if (verdict == NF_ACCEPT ||
 233             verdict == NF_REPEAT ||
 234             verdict == NF_STOP) {
 235                 unsigned int ct_verdict = verdict;
 236
 237                 rcu_read_lock();
 238                 ct_hook = rcu_dereference(nf_ct_hook);
 239                 if (ct_hook)
 240                         ct_verdict = ct_hook->update(entry->state.net, entry->skb);
 241                 rcu_read_unlock();
 242
 243                 switch (ct_verdict & NF_VERDICT_MASK) {
 244                 case NF_ACCEPT:
 245                         /* follow userspace verdict, could be REPEAT */
 246                         break;
 247                 case NF_STOLEN:
 248                         nf_queue_entry_free(entry);
 249                         return;
 250                 default:
 251                         verdict = ct_verdict & NF_VERDICT_MASK;
 252                         break;
 253                 }
 254         }
 255         nf_reinject(entry, verdict);
 256 }
 257
 258 static void
 259 nfqnl_flush(struct nfqnl_instance *queue, nfqnl_cmpfn cmpfn, unsigned long data)
 260 {
 261         struct nf_queue_entry *entry, *next;
 262
 263         spin_lock_bh(&queue->lock);
 264         list_for_each_entry_safe(entry, next, &queue->queue_list, list) {
 265                 if (!cmpfn || cmpfn(entry, data)) {
 266                         list_del(&entry->list);
 267                         queue->queue_total--;
 268                         nfqnl_reinject(entry, NF_DROP);
 269                 }
 270         }
 271         spin_unlock_bh(&queue->lock);
 272 }
 273
 274 static int
 275 nfqnl_put_packet_info(struct sk_buff *nlskb, struct sk_buff *packet,
 276                       bool csum_verify)
 277 {
 278         __u32 flags = 0;
 279
 280         if (packet->ip_summed == CHECKSUM_PARTIAL)
 281                 flags = NFQA_SKB_CSUMNOTREADY;
 282         else if (csum_verify)
 283                 flags = NFQA_SKB_CSUM_NOTVERIFIED;
 284
 285         if (skb_is_gso(packet))
 286                 flags |= NFQA_SKB_GSO;
 287
 288         return flags ? nla_put_be32(nlskb, NFQA_SKB_INFO, htonl(flags)) : 0;
 289 }
 290
 291 static int nfqnl_put_sk_uidgid(struct sk_buff *skb, struct sock *sk)
 292 {
 293         const struct cred *cred;
 294
 295         if (!sk_fullsock(sk))
 296                 return 0;
 297
 298         read_lock_bh(&sk->sk_callback_lock);
 299         if (sk->sk_socket && sk->sk_socket->file) {
 300                 cred = sk->sk_socket->file->f_cred;
 301                 if (nla_put_be32(skb, NFQA_UID,
 302                     htonl(from_kuid_munged(&init_user_ns, cred->fsuid))))
 303                         goto nla_put_failure;
 304                 if (nla_put_be32(skb, NFQA_GID,
 305                     htonl(from_kgid_munged(&init_user_ns, cred->fsgid))))
 306                         goto nla_put_failure;
 307         }
 308         read_unlock_bh(&sk->sk_callback_lock);
 309         return 0;
 310
 311 nla_put_failure:
 312         read_unlock_bh(&sk->sk_callback_lock);
 313         return -1;
 314 }
 315
 316 static int nfqnl_put_sk_classid(struct sk_buff *skb, struct sock *sk)
 317 {
 318 #if IS_ENABLED(CONFIG_CGROUP_NET_CLASSID)
 319         if (sk && sk_fullsock(sk)) {
 320                 u32 classid = sock_cgroup_classid(&sk->sk_cgrp_data);
 321
 322                 if (classid && nla_put_be32(skb, NFQA_CGROUP_CLASSID, htonl(classid)))
 323                         return -1;
 324         }
 325 #endif
 326         return 0;
 327 }
 328
 329 static u32 nfqnl_get_sk_secctx(struct sk_buff *skb, char **secdata)
 330 {
 331         u32 seclen = 0;
 332 #if IS_ENABLED(CONFIG_NETWORK_SECMARK)
 333         if (!skb || !sk_fullsock(skb->sk))
 334                 return 0;
 335
 336         read_lock_bh(&skb->sk->sk_callback_lock);
 337
 338         if (skb->secmark)
 339                 security_secid_to_secctx(skb->secmark, secdata, &seclen);
 340
 341         read_unlock_bh(&skb->sk->sk_callback_lock);
 342 #endif
 343         return seclen;
 344 }
 345
 346 static u32 nfqnl_get_bridge_size(struct nf_queue_entry *entry)
 347 {
 348         struct sk_buff *entskb = entry->skb;
 349         u32 nlalen = 0;
 350
 351         if (entry->state.pf != PF_BRIDGE || !skb_mac_header_was_set(entskb))
 352                 return 0;
 353
 354         if (skb_vlan_tag_present(entskb))
 355                 nlalen += nla_total_size(nla_total_size(sizeof(__be16)) +
 356                                          nla_total_size(sizeof(__be16)));
 357
 358         if (entskb->network_header > entskb->mac_header)
 359                 nlalen += nla_total_size((entskb->network_header -
 360                                           entskb->mac_header));
 361
 362         return nlalen;
 363 }
 364
 365 static int nfqnl_put_bridge(struct nf_queue_entry *entry, struct sk_buff *skb)
 366 {
 367         struct sk_buff *entskb = entry->skb;
 368
 369         if (entry->state.pf != PF_BRIDGE || !skb_mac_header_was_set(entskb))
 370                 return 0;
 371
 372         if (skb_vlan_tag_present(entskb)) {
 373                 struct nlattr *nest;
 374
 375                 nest = nla_nest_start(skb, NFQA_VLAN);
 376                 if (!nest)
 377                         goto nla_put_failure;
 378
 379                 if (nla_put_be16(skb, NFQA_VLAN_TCI, htons(entskb->vlan_tci)) ||
 380                     nla_put_be16(skb, NFQA_VLAN_PROTO, entskb->vlan_proto))
 381                         goto nla_put_failure;
 382
 383                 nla_nest_end(skb, nest);
 384         }
 385
 386         if (entskb->mac_header < entskb->network_header) {
 387                 int len = (int)(entskb->network_header - entskb->mac_header);
 388
 389                 if (nla_put(skb, NFQA_L2HDR, len, skb_mac_header(entskb)))
 390                         goto nla_put_failure;
 391         }
 392
 393         return 0;
 394
 395 nla_put_failure:
 396         return -1;
 397 }
 398
 399 static struct sk_buff *
 400 nfqnl_build_packet_message(struct net *net, struct nfqnl_instance *queue,
 401                            struct nf_queue_entry *entry,
 402                            __be32 **packet_id_ptr)
 403 {
 404         size_t size;
 405         size_t data_len = 0, cap_len = 0;
 406         unsigned int hlen = 0;
 407         struct sk_buff *skb;
 408         struct nlattr *nla;
 409         struct nfqnl_msg_packet_hdr *pmsg;
 410         struct nlmsghdr *nlh;
 411         struct sk_buff *entskb = entry->skb;
 412         struct net_device *indev;
 413         struct net_device *outdev;
 414         struct nf_conn *ct = NULL;
 415         enum ip_conntrack_info ctinfo = 0;
 416         const struct nfnl_ct_hook *nfnl_ct;
 417         bool csum_verify;
 418         char *secdata = NULL;
 419         u32 seclen = 0;
 420         ktime_t tstamp;
 421
 422         size = nlmsg_total_size(sizeof(struct nfgenmsg))
 423                 + nla_total_size(sizeof(struct nfqnl_msg_packet_hdr))
 424                 + nla_total_size(sizeof(u_int32_t))     /* ifindex */
 425                 + nla_total_size(sizeof(u_int32_t))     /* ifindex */
 426 #if IS_ENABLED(CONFIG_BRIDGE_NETFILTER)
 427                 + nla_total_size(sizeof(u_int32_t))     /* ifindex */
 428                 + nla_total_size(sizeof(u_int32_t))     /* ifindex */
 429 #endif
 430                 + nla_total_size(sizeof(u_int32_t))     /* mark */
 431                 + nla_total_size(sizeof(u_int32_t))     /* priority */
 432                 + nla_total_size(sizeof(struct nfqnl_msg_packet_hw))
 433                 + nla_total_size(sizeof(u_int32_t))     /* skbinfo */
 434 #if IS_ENABLED(CONFIG_CGROUP_NET_CLASSID)
 435                 + nla_total_size(sizeof(u_int32_t))     /* classid */
 436 #endif
 437                 + nla_total_size(sizeof(u_int32_t));    /* cap_len */
 438
 439         tstamp = skb_tstamp_cond(entskb, false);
 440         if (tstamp)
 441                 size += nla_total_size(sizeof(struct nfqnl_msg_packet_timestamp));
 442
 443         size += nfqnl_get_bridge_size(entry);
 444
 445         if (entry->state.hook <= NF_INET_FORWARD ||
 446            (entry->state.hook == NF_INET_POST_ROUTING && entskb->sk == NULL))
 447                 csum_verify = !skb_csum_unnecessary(entskb);
 448         else
 449                 csum_verify = false;
 450
 451         outdev = entry->state.out;
 452
 453         switch ((enum nfqnl_config_mode)READ_ONCE(queue->copy_mode)) {
 454         case NFQNL_COPY_META:
 455         case NFQNL_COPY_NONE:
 456                 break;
 457
 458         case NFQNL_COPY_PACKET:
 459                 if (!(queue->flags & NFQA_CFG_F_GSO) &&
 460                     entskb->ip_summed == CHECKSUM_PARTIAL &&
 461                     skb_checksum_help(entskb))
 462                         return NULL;
 463
 464                 data_len = READ_ONCE(queue->copy_range);
 465                 if (data_len > entskb->len)
 466                         data_len = entskb->len;
 467
 468                 hlen = skb_zerocopy_headlen(entskb);
 469                 hlen = min_t(unsigned int, hlen, data_len);
 470                 size += sizeof(struct nlattr) + hlen;
 471                 cap_len = entskb->len;
 472                 break;
 473         }
 474
 475         nfnl_ct = rcu_dereference(nfnl_ct_hook);
 476
 477 #if IS_ENABLED(CONFIG_NF_CONNTRACK)
 478         if (queue->flags & NFQA_CFG_F_CONNTRACK) {
 479                 if (nfnl_ct != NULL) {
 480                         ct = nf_ct_get(entskb, &ctinfo);
 481                         if (ct != NULL)
 482                                 size += nfnl_ct->build_size(ct);
 483                 }
 484         }
 485 #endif
 486
 487         if (queue->flags & NFQA_CFG_F_UID_GID) {
 488                 size += (nla_total_size(sizeof(u_int32_t))      /* uid */
 489                         + nla_total_size(sizeof(u_int32_t)));   /* gid */
 490         }
 491
 492         if ((queue->flags & NFQA_CFG_F_SECCTX) && entskb->sk) {
 493                 seclen = nfqnl_get_sk_secctx(entskb, &secdata);
 494                 if (seclen)
 495                         size += nla_total_size(seclen);
 496         }
 497
 498         skb = alloc_skb(size, GFP_ATOMIC);
 499         if (!skb) {
 500                 skb_tx_error(entskb);
 501                 goto nlmsg_failure;
 502         }
 503
 504         nlh = nfnl_msg_put(skb, 0, 0,
 505                            nfnl_msg_type(NFNL_SUBSYS_QUEUE, NFQNL_MSG_PACKET),
 506                            0, entry->state.pf, NFNETLINK_V0,
 507                            htons(queue->queue_num));
 508         if (!nlh) {
 509                 skb_tx_error(entskb);
 510                 kfree_skb(skb);
 511                 goto nlmsg_failure;
 512         }
 513
 514         nla = __nla_reserve(skb, NFQA_PACKET_HDR, sizeof(*pmsg));
 515         pmsg = nla_data(nla);
 516         pmsg->hw_protocol       = entskb->protocol;
 517         pmsg->hook              = entry->state.hook;
 518         *packet_id_ptr          = &pmsg->packet_id;
 519
 520         indev = entry->state.in;
 521         if (indev) {
 522 #if !IS_ENABLED(CONFIG_BRIDGE_NETFILTER)
 523                 if (nla_put_be32(skb, NFQA_IFINDEX_INDEV, htonl(indev->ifindex)))
 524                         goto nla_put_failure;
 525 #else
 526                 if (entry->state.pf == PF_BRIDGE) {
 527                         /* Case 1: indev is physical input device, we need to
 528                          * look for bridge group (when called from
 529                          * netfilter_bridge) */
 530                         if (nla_put_be32(skb, NFQA_IFINDEX_PHYSINDEV,
 531                                          htonl(indev->ifindex)) ||
 532                         /* this is the bridge group "brX" */
 533                         /* rcu_read_lock()ed by __nf_queue */
 534                             nla_put_be32(skb, NFQA_IFINDEX_INDEV,
 535                                          htonl(br_port_get_rcu(indev)->br->dev->ifindex)))
 536                                 goto nla_put_failure;
 537                 } else {
 538                         int physinif;
 539
 540                         /* Case 2: indev is bridge group, we need to look for
 541                          * physical device (when called from ipv4) */
 542                         if (nla_put_be32(skb, NFQA_IFINDEX_INDEV,
 543                                          htonl(indev->ifindex)))
 544                                 goto nla_put_failure;
 545
 546                         physinif = nf_bridge_get_physinif(entskb);
 547                         if (physinif &&
 548                             nla_put_be32(skb, NFQA_IFINDEX_PHYSINDEV,
 549                                          htonl(physinif)))
 550                                 goto nla_put_failure;
 551                 }
 552 #endif
 553         }
 554
 555         if (outdev) {
 556 #if !IS_ENABLED(CONFIG_BRIDGE_NETFILTER)
 557                 if (nla_put_be32(skb, NFQA_IFINDEX_OUTDEV, htonl(outdev->ifindex)))
 558                         goto nla_put_failure;
 559 #else
 560                 if (entry->state.pf == PF_BRIDGE) {
 561                         /* Case 1: outdev is physical output device, we need to
 562                          * look for bridge group (when called from
 563                          * netfilter_bridge) */
 564                         if (nla_put_be32(skb, NFQA_IFINDEX_PHYSOUTDEV,
 565                                          htonl(outdev->ifindex)) ||
 566                         /* this is the bridge group "brX" */
 567                         /* rcu_read_lock()ed by __nf_queue */
 568                             nla_put_be32(skb, NFQA_IFINDEX_OUTDEV,
 569                                          htonl(br_port_get_rcu(outdev)->br->dev->ifindex)))
 570                                 goto nla_put_failure;
 571                 } else {
 572                         int physoutif;
 573
 574                         /* Case 2: outdev is bridge group, we need to look for
 575                          * physical output device (when called from ipv4) */
 576                         if (nla_put_be32(skb, NFQA_IFINDEX_OUTDEV,
 577                                          htonl(outdev->ifindex)))
 578                                 goto nla_put_failure;
 579
 580                         physoutif = nf_bridge_get_physoutif(entskb);
 581                         if (physoutif &&
 582                             nla_put_be32(skb, NFQA_IFINDEX_PHYSOUTDEV,
 583                                          htonl(physoutif)))
 584                                 goto nla_put_failure;
 585                 }
 586 #endif
 587         }
 588
 589         if (entskb->mark &&
 590             nla_put_be32(skb, NFQA_MARK, htonl(entskb->mark)))
 591                 goto nla_put_failure;
 592
 593         if (entskb->priority &&
 594             nla_put_be32(skb, NFQA_PRIORITY, htonl(entskb->priority)))
 595                 goto nla_put_failure;
 596
 597         if (indev && entskb->dev &&
 598             skb_mac_header_was_set(entskb) &&
 599             skb_mac_header_len(entskb) != 0) {
 600                 struct nfqnl_msg_packet_hw phw;
 601                 int len;
 602
 603                 memset(&phw, 0, sizeof(phw));
 604                 len = dev_parse_header(entskb, phw.hw_addr);
 605                 if (len) {
 606                         phw.hw_addrlen = htons(len);
 607                         if (nla_put(skb, NFQA_HWADDR, sizeof(phw), &phw))
 608                                 goto nla_put_failure;
 609                 }
 610         }
 611
 612         if (nfqnl_put_bridge(entry, skb) < 0)
 613                 goto nla_put_failure;
 614
 615         if (entry->state.hook <= NF_INET_FORWARD && tstamp) {
 616                 struct nfqnl_msg_packet_timestamp ts;
 617                 struct timespec64 kts = ktime_to_timespec64(tstamp);
 618
 619                 ts.sec = cpu_to_be64(kts.tv_sec);
 620                 ts.usec = cpu_to_be64(kts.tv_nsec / NSEC_PER_USEC);
 621
 622                 if (nla_put(skb, NFQA_TIMESTAMP, sizeof(ts), &ts))
 623                         goto nla_put_failure;
 624         }
 625
 626         if ((queue->flags & NFQA_CFG_F_UID_GID) && entskb->sk &&
 627             nfqnl_put_sk_uidgid(skb, entskb->sk) < 0)
 628                 goto nla_put_failure;
 629
 630         if (nfqnl_put_sk_classid(skb, entskb->sk) < 0)
 631                 goto nla_put_failure;
 632
 633         if (seclen && nla_put(skb, NFQA_SECCTX, seclen, secdata))
 634                 goto nla_put_failure;
 635
 636         if (ct && nfnl_ct->build(skb, ct, ctinfo, NFQA_CT, NFQA_CT_INFO) < 0)
 637                 goto nla_put_failure;
 638
 639         if (cap_len > data_len &&
 640             nla_put_be32(skb, NFQA_CAP_LEN, htonl(cap_len)))
 641                 goto nla_put_failure;
 642
 643         if (nfqnl_put_packet_info(skb, entskb, csum_verify))
 644                 goto nla_put_failure;
 645
 646         if (data_len) {
 647                 struct nlattr *nla;
 648
 649                 if (skb_tailroom(skb) < sizeof(*nla) + hlen)
 650                         goto nla_put_failure;
 651
 652                 nla = skb_put(skb, sizeof(*nla));
 653                 nla->nla_type = NFQA_PAYLOAD;
 654                 nla->nla_len = nla_attr_size(data_len);
 655
 656                 if (skb_zerocopy(skb, entskb, data_len, hlen))
 657                         goto nla_put_failure;
 658         }
 659
 660         nlh->nlmsg_len = skb->len;
 661         if (seclen)
 662                 security_release_secctx(secdata, seclen);
 663         return skb;
 664
 665 nla_put_failure:
 666         skb_tx_error(entskb);
 667         kfree_skb(skb);
 668         net_err_ratelimited("nf_queue: error creating packet message\n");
 669 nlmsg_failure:
 670         if (seclen)
 671                 security_release_secctx(secdata, seclen);
 672         return NULL;
 673 }
 674
 675 static bool nf_ct_drop_unconfirmed(const struct nf_queue_entry *entry)
 676 {
 677 #if IS_ENABLED(CONFIG_NF_CONNTRACK)
 678         static const unsigned long flags = IPS_CONFIRMED | IPS_DYING;
 679         const struct nf_conn *ct = (void *)skb_nfct(entry->skb);
 680
 681         if (ct && ((ct->status & flags) == IPS_DYING))
 682                 return true;
 683 #endif
 684         return false;
 685 }
 686
 687 static int
 688 __nfqnl_enqueue_packet(struct net *net, struct nfqnl_instance *queue,
 689                         struct nf_queue_entry *entry)
 690 {
 691         struct sk_buff *nskb;
 692         int err = -ENOBUFS;
 693         __be32 *packet_id_ptr;
 694         int failopen = 0;
 695
 696         nskb = nfqnl_build_packet_message(net, queue, entry, &packet_id_ptr);
 697         if (nskb == NULL) {
 698                 err = -ENOMEM;
 699                 goto err_out;
 700         }
 701         spin_lock_bh(&queue->lock);
 702
 703         if (nf_ct_drop_unconfirmed(entry))
 704                 goto err_out_free_nskb;
 705
 706         if (queue->queue_total >= queue->queue_maxlen) {
 707                 if (queue->flags & NFQA_CFG_F_FAIL_OPEN) {
 708                         failopen = 1;
 709                         err = 0;
 710                 } else {
 711                         queue->queue_dropped++;
 712                         net_warn_ratelimited("nf_queue: full at %d entries, dropping packets(s)\n",
 713                                              queue->queue_total);
 714                 }
 715                 goto err_out_free_nskb;
 716         }
 717         entry->id = ++queue->id_sequence;
 718         *packet_id_ptr = htonl(entry->id);
 719
 720         /* nfnetlink_unicast will either free the nskb or add it to a socket */
 721         err = nfnetlink_unicast(nskb, net, queue->peer_portid);
 722         if (err < 0) {
 723                 if (queue->flags & NFQA_CFG_F_FAIL_OPEN) {
 724                         failopen = 1;
 725                         err = 0;
 726                 } else {
 727                         queue->queue_user_dropped++;
 728                 }
 729                 goto err_out_unlock;
 730         }
 731
 732         __enqueue_entry(queue, entry);
 733
 734         spin_unlock_bh(&queue->lock);
 735         return 0;
 736
 737 err_out_free_nskb:
 738         kfree_skb(nskb);
 739 err_out_unlock:
 740         spin_unlock_bh(&queue->lock);
 741         if (failopen)
 742                 nfqnl_reinject(entry, NF_ACCEPT);
 743 err_out:
 744         return err;
 745 }
 746
 747 static struct nf_queue_entry *
 748 nf_queue_entry_dup(struct nf_queue_entry *e)
 749 {
 750         struct nf_queue_entry *entry = kmemdup(e, e->size, GFP_ATOMIC);
 751
 752         if (!entry)
 753                 return NULL;
 754
 755         if (nf_queue_entry_get_refs(entry))
 756                 return entry;
 757
 758         kfree(entry);
 759         return NULL;
 760 }
 761
 762 #if IS_ENABLED(CONFIG_BRIDGE_NETFILTER)
 763 /* When called from bridge netfilter, skb->data must point to MAC header
 764  * before calling skb_gso_segment(). Else, original MAC header is lost
 765  * and segmented skbs will be sent to wrong destination.
 766  */
 767 static void nf_bridge_adjust_skb_data(struct sk_buff *skb)
 768 {
 769         if (nf_bridge_info_get(skb))
 770                 __skb_push(skb, skb->network_header - skb->mac_header);
 771 }
 772
 773 static void nf_bridge_adjust_segmented_data(struct sk_buff *skb)
 774 {
 775         if (nf_bridge_info_get(skb))
 776                 __skb_pull(skb, skb->network_header - skb->mac_header);
 777 }
 778 #else
 779 #define nf_bridge_adjust_skb_data(s) do {} while (0)
 780 #define nf_bridge_adjust_segmented_data(s) do {} while (0)
 781 #endif
 782
 783 static int
 784 __nfqnl_enqueue_packet_gso(struct net *net, struct nfqnl_instance *queue,
 785                            struct sk_buff *skb, struct nf_queue_entry *entry)
 786 {
 787         int ret = -ENOMEM;
 788         struct nf_queue_entry *entry_seg;
 789
 790         nf_bridge_adjust_segmented_data(skb);
 791
 792         if (skb->next == NULL) { /* last packet, no need to copy entry */
 793                 struct sk_buff *gso_skb = entry->skb;
 794                 entry->skb = skb;
 795                 ret = __nfqnl_enqueue_packet(net, queue, entry);
 796                 if (ret)
 797                         entry->skb = gso_skb;
 798                 return ret;
 799         }
 800
 801         skb_mark_not_on_list(skb);
 802
 803         entry_seg = nf_queue_entry_dup(entry);
 804         if (entry_seg) {
 805                 entry_seg->skb = skb;
 806                 ret = __nfqnl_enqueue_packet(net, queue, entry_seg);
 807                 if (ret)
 808                         nf_queue_entry_free(entry_seg);
 809         }
 810         return ret;
 811 }
 812
 813 static int
 814 nfqnl_enqueue_packet(struct nf_queue_entry *entry, unsigned int queuenum)
 815 {
 816         unsigned int queued;
 817         struct nfqnl_instance *queue;
 818         struct sk_buff *skb, *segs, *nskb;
 819         int err = -ENOBUFS;
 820         struct net *net = entry->state.net;
 821         struct nfnl_queue_net *q = nfnl_queue_pernet(net);
 822
 823         /* rcu_read_lock()ed by nf_hook_thresh */
 824         queue = instance_lookup(q, queuenum);
 825         if (!queue)
 826                 return -ESRCH;
 827
 828         if (queue->copy_mode == NFQNL_COPY_NONE)
 829                 return -EINVAL;
 830
 831         skb = entry->skb;
 832
 833         switch (entry->state.pf) {
 834         case NFPROTO_IPV4:
 835                 skb->protocol = htons(ETH_P_IP);
 836                 break;
 837         case NFPROTO_IPV6:
 838                 skb->protocol = htons(ETH_P_IPV6);
 839                 break;
 840         }
 841
 842         if ((queue->flags & NFQA_CFG_F_GSO) || !skb_is_gso(skb))
 843                 return __nfqnl_enqueue_packet(net, queue, entry);
 844
 845         nf_bridge_adjust_skb_data(skb);
 846         segs = skb_gso_segment(skb, 0);
 847         /* Does not use PTR_ERR to limit the number of error codes that can be
 848          * returned by nf_queue.  For instance, callers rely on -ESRCH to
 849          * mean 'ignore this hook'.
 850          */
 851         if (IS_ERR_OR_NULL(segs))
 852                 goto out_err;
 853         queued = 0;
 854         err = 0;
 855         skb_list_walk_safe(segs, segs, nskb) {
 856                 if (err == 0)
 857                         err = __nfqnl_enqueue_packet_gso(net, queue,
 858                                                         segs, entry);
 859                 if (err == 0)
 860                         queued++;
 861                 else
 862                         kfree_skb(segs);
 863         }
 864
 865         if (queued) {
 866                 if (err) /* some segments are already queued */
 867                         nf_queue_entry_free(entry);
 868                 kfree_skb(skb);
 869                 return 0;
 870         }
 871  out_err:
 872         nf_bridge_adjust_segmented_data(skb);
 873         return err;
 874 }
 875
 876 static int
 877 nfqnl_mangle(void *data, unsigned int data_len, struct nf_queue_entry *e, int diff)
 878 {
 879         struct sk_buff *nskb;
 880
 881         if (diff < 0) {
 882                 unsigned int min_len = skb_transport_offset(e->skb);
 883
 884                 if (data_len < min_len)
 885                         return -EINVAL;
 886
 887                 if (pskb_trim(e->skb, data_len))
 888                         return -ENOMEM;
 889         } else if (diff > 0) {
 890                 if (data_len > 0xFFFF)
 891                         return -EINVAL;
 892                 if (diff > skb_tailroom(e->skb)) {
 893                         nskb = skb_copy_expand(e->skb, skb_headroom(e->skb),
 894                                                diff, GFP_ATOMIC);
 895                         if (!nskb)
 896                                 return -ENOMEM;
 897                         kfree_skb(e->skb);
 898                         e->skb = nskb;
 899                 }
 900                 skb_put(e->skb, diff);
 901         }
 902         if (skb_ensure_writable(e->skb, data_len))
 903                 return -ENOMEM;
 904         skb_copy_to_linear_data(e->skb, data, data_len);
 905         e->skb->ip_summed = CHECKSUM_NONE;
 906         return 0;
 907 }
 908
 909 static int
 910 nfqnl_set_mode(struct nfqnl_instance *queue,
 911                unsigned char mode, unsigned int range)
 912 {
 913         int status = 0;
 914
 915         spin_lock_bh(&queue->lock);
 916         switch (mode) {
 917         case NFQNL_COPY_NONE:
 918         case NFQNL_COPY_META:
 919                 queue->copy_mode = mode;
 920                 queue->copy_range = 0;
 921                 break;
 922
 923         case NFQNL_COPY_PACKET:
 924                 queue->copy_mode = mode;
 925                 if (range == 0 || range > NFQNL_MAX_COPY_RANGE)
 926                         queue->copy_range = NFQNL_MAX_COPY_RANGE;
 927                 else
 928                         queue->copy_range = range;
 929                 break;
 930
 931         default:
 932                 status = -EINVAL;
 933
 934         }
 935         spin_unlock_bh(&queue->lock);
 936
 937         return status;
 938 }
 939
 940 static int
 941 dev_cmp(struct nf_queue_entry *entry, unsigned long ifindex)
 942 {
 943 #if IS_ENABLED(CONFIG_BRIDGE_NETFILTER)
 944         int physinif, physoutif;
 945
 946         physinif = nf_bridge_get_physinif(entry->skb);
 947         physoutif = nf_bridge_get_physoutif(entry->skb);
 948
 949         if (physinif == ifindex || physoutif == ifindex)
 950                 return 1;
 951 #endif
 952         if (entry->state.in)
 953                 if (entry->state.in->ifindex == ifindex)
 954                         return 1;
 955         if (entry->state.out)
 956                 if (entry->state.out->ifindex == ifindex)
 957                         return 1;
 958
 959         return 0;
 960 }
 961
 962 /* drop all packets with either indev or outdev == ifindex from all queue
 963  * instances */
 964 static void
 965 nfqnl_dev_drop(struct net *net, int ifindex)
 966 {
 967         int i;
 968         struct nfnl_queue_net *q = nfnl_queue_pernet(net);
 969
 970         rcu_read_lock();
 971
 972         for (i = 0; i < INSTANCE_BUCKETS; i++) {
 973                 struct nfqnl_instance *inst;
 974                 struct hlist_head *head = &q->instance_table[i];
 975
 976                 hlist_for_each_entry_rcu(inst, head, hlist)
 977                         nfqnl_flush(inst, dev_cmp, ifindex);
 978         }
 979
 980         rcu_read_unlock();
 981 }
 982
 983 static int
 984 nfqnl_rcv_dev_event(struct notifier_block *this,
 985                     unsigned long event, void *ptr)
 986 {
 987         struct net_device *dev = netdev_notifier_info_to_dev(ptr);
 988
 989         /* Drop any packets associated with the downed device */
 990         if (event == NETDEV_DOWN)
 991                 nfqnl_dev_drop(dev_net(dev), dev->ifindex);
 992         return NOTIFY_DONE;
 993 }
 994
 995 static struct notifier_block nfqnl_dev_notifier = {
 996         .notifier_call  = nfqnl_rcv_dev_event,
 997 };
 998
 999 static void nfqnl_nf_hook_drop(struct net *net)
1000 {
1001         struct nfnl_queue_net *q = nfnl_queue_pernet(net);
1002         int i;
1003
1004         /* This function is also called on net namespace error unwind,
1005          * when pernet_ops->init() failed and ->exit() functions of the
1006          * previous pernet_ops gets called.
1007          *
1008          * This may result in a call to nfqnl_nf_hook_drop() before
1009          * struct nfnl_queue_net was allocated.
1010          */
1011         if (!q)
1012                 return;
1013
1014         for (i = 0; i < INSTANCE_BUCKETS; i++) {
1015                 struct nfqnl_instance *inst;
1016                 struct hlist_head *head = &q->instance_table[i];
1017
1018                 hlist_for_each_entry_rcu(inst, head, hlist)
1019                         nfqnl_flush(inst, NULL, 0);
1020         }
1021 }
1022
1023 static int
1024 nfqnl_rcv_nl_event(struct notifier_block *this,
1025                    unsigned long event, void *ptr)
1026 {
1027         struct netlink_notify *n = ptr;
1028         struct nfnl_queue_net *q = nfnl_queue_pernet(n->net);
1029
1030         if (event == NETLINK_URELEASE && n->protocol == NETLINK_NETFILTER) {
1031                 int i;
1032
1033                 /* destroy all instances for this portid */
1034                 spin_lock(&q->instances_lock);
1035                 for (i = 0; i < INSTANCE_BUCKETS; i++) {
1036                         struct hlist_node *t2;
1037                         struct nfqnl_instance *inst;
1038                         struct hlist_head *head = &q->instance_table[i];
1039
1040                         hlist_for_each_entry_safe(inst, t2, head, hlist) {
1041                                 if (n->portid == inst->peer_portid)
1042                                         __instance_destroy(inst);
1043                         }
1044                 }
1045                 spin_unlock(&q->instances_lock);
1046         }
1047         return NOTIFY_DONE;
1048 }
1049
1050 static struct notifier_block nfqnl_rtnl_notifier = {
1051         .notifier_call  = nfqnl_rcv_nl_event,
1052 };
1053
1054 static const struct nla_policy nfqa_vlan_policy[NFQA_VLAN_MAX + 1] = {
1055         [NFQA_VLAN_TCI]         = { .type = NLA_U16},
1056         [NFQA_VLAN_PROTO]       = { .type = NLA_U16},
1057 };
1058
1059 static const struct nla_policy nfqa_verdict_policy[NFQA_MAX+1] = {
1060         [NFQA_VERDICT_HDR]      = { .len = sizeof(struct nfqnl_msg_verdict_hdr) },
1061         [NFQA_MARK]             = { .type = NLA_U32 },
1062         [NFQA_PAYLOAD]          = { .type = NLA_UNSPEC },
1063         [NFQA_CT]               = { .type = NLA_UNSPEC },
1064         [NFQA_EXP]              = { .type = NLA_UNSPEC },
1065         [NFQA_VLAN]             = { .type = NLA_NESTED },
1066         [NFQA_PRIORITY]         = { .type = NLA_U32 },
1067 };
1068
1069 static const struct nla_policy nfqa_verdict_batch_policy[NFQA_MAX+1] = {
1070         [NFQA_VERDICT_HDR]      = { .len = sizeof(struct nfqnl_msg_verdict_hdr) },
1071         [NFQA_MARK]             = { .type = NLA_U32 },
1072         [NFQA_PRIORITY]         = { .type = NLA_U32 },
1073 };
1074
1075 static struct nfqnl_instance *
1076 verdict_instance_lookup(struct nfnl_queue_net *q, u16 queue_num, u32 nlportid)
1077 {
1078         struct nfqnl_instance *queue;
1079
1080         queue = instance_lookup(q, queue_num);
1081         if (!queue)
1082                 return ERR_PTR(-ENODEV);
1083
1084         if (queue->peer_portid != nlportid)
1085                 return ERR_PTR(-EPERM);
1086
1087         return queue;
1088 }
1089
1090 static struct nfqnl_msg_verdict_hdr*
1091 verdicthdr_get(const struct nlattr * const nfqa[])
1092 {
1093         struct nfqnl_msg_verdict_hdr *vhdr;
1094         unsigned int verdict;
1095
1096         if (!nfqa[NFQA_VERDICT_HDR])
1097                 return NULL;
1098
1099         vhdr = nla_data(nfqa[NFQA_VERDICT_HDR]);
1100         verdict = ntohl(vhdr->verdict) & NF_VERDICT_MASK;
1101         if (verdict > NF_MAX_VERDICT || verdict == NF_STOLEN)
1102                 return NULL;
1103         return vhdr;
1104 }
1105
1106 static int nfq_id_after(unsigned int id, unsigned int max)
1107 {
1108         return (int)(id - max) > 0;
1109 }
1110
1111 static int nfqnl_recv_verdict_batch(struct sk_buff *skb,
1112                                     const struct nfnl_info *info,
1113                                     const struct nlattr * const nfqa[])
1114 {
1115         struct nfnl_queue_net *q = nfnl_queue_pernet(info->net);
1116         u16 queue_num = ntohs(info->nfmsg->res_id);
1117         struct nf_queue_entry *entry, *tmp;
1118         struct nfqnl_msg_verdict_hdr *vhdr;
1119         struct nfqnl_instance *queue;
1120         unsigned int verdict, maxid;
1121         LIST_HEAD(batch_list);
1122
1123         queue = verdict_instance_lookup(q, queue_num,
1124                                         NETLINK_CB(skb).portid);
1125         if (IS_ERR(queue))
1126                 return PTR_ERR(queue);
1127
1128         vhdr = verdicthdr_get(nfqa);
1129         if (!vhdr)
1130                 return -EINVAL;
1131
1132         verdict = ntohl(vhdr->verdict);
1133         maxid = ntohl(vhdr->id);
1134
1135         spin_lock_bh(&queue->lock);
1136
1137         list_for_each_entry_safe(entry, tmp, &queue->queue_list, list) {
1138                 if (nfq_id_after(entry->id, maxid))
1139                         break;
1140                 __dequeue_entry(queue, entry);
1141                 list_add_tail(&entry->list, &batch_list);
1142         }
1143
1144         spin_unlock_bh(&queue->lock);
1145
1146         if (list_empty(&batch_list))
1147                 return -ENOENT;
1148
1149         list_for_each_entry_safe(entry, tmp, &batch_list, list) {
1150                 if (nfqa[NFQA_MARK])
1151                         entry->skb->mark = ntohl(nla_get_be32(nfqa[NFQA_MARK]));
1152
1153                 if (nfqa[NFQA_PRIORITY])
1154                         entry->skb->priority = ntohl(nla_get_be32(nfqa[NFQA_PRIORITY]));
1155
1156                 nfqnl_reinject(entry, verdict);
1157         }
1158         return 0;
1159 }
1160
1161 static struct nf_conn *nfqnl_ct_parse(const struct nfnl_ct_hook *nfnl_ct,
1162                                       const struct nlmsghdr *nlh,
1163                                       const struct nlattr * const nfqa[],
1164                                       struct nf_queue_entry *entry,
1165                                       enum ip_conntrack_info *ctinfo)
1166 {
1167 #if IS_ENABLED(CONFIG_NF_CONNTRACK)
1168         struct nf_conn *ct;
1169
1170         ct = nf_ct_get(entry->skb, ctinfo);
1171         if (ct == NULL)
1172                 return NULL;
1173
1174         if (nfnl_ct->parse(nfqa[NFQA_CT], ct) < 0)
1175                 return NULL;
1176
1177         if (nfqa[NFQA_EXP])
1178                 nfnl_ct->attach_expect(nfqa[NFQA_EXP], ct,
1179                                       NETLINK_CB(entry->skb).portid,
1180                                       nlmsg_report(nlh));
1181         return ct;
1182 #else
1183         return NULL;
1184 #endif
1185 }
1186
1187 static int nfqa_parse_bridge(struct nf_queue_entry *entry,
1188                              const struct nlattr * const nfqa[])
1189 {
1190         if (nfqa[NFQA_VLAN]) {
1191                 struct nlattr *tb[NFQA_VLAN_MAX + 1];
1192                 int err;
1193
1194                 err = nla_parse_nested_deprecated(tb, NFQA_VLAN_MAX,
1195                                                   nfqa[NFQA_VLAN],
1196                                                   nfqa_vlan_policy, NULL);
1197                 if (err < 0)
1198                         return err;
1199
1200                 if (!tb[NFQA_VLAN_TCI] || !tb[NFQA_VLAN_PROTO])
1201                         return -EINVAL;
1202
1203                 __vlan_hwaccel_put_tag(entry->skb,
1204                         nla_get_be16(tb[NFQA_VLAN_PROTO]),
1205                         ntohs(nla_get_be16(tb[NFQA_VLAN_TCI])));
1206         }
1207
1208         if (nfqa[NFQA_L2HDR]) {
1209                 int mac_header_len = entry->skb->network_header -
1210                         entry->skb->mac_header;
1211
1212                 if (mac_header_len != nla_len(nfqa[NFQA_L2HDR]))
1213                         return -EINVAL;
1214                 else if (mac_header_len > 0)
1215                         memcpy(skb_mac_header(entry->skb),
1216                                nla_data(nfqa[NFQA_L2HDR]),
1217                                mac_header_len);
1218         }
1219
1220         return 0;
1221 }
1222
1223 static int nfqnl_recv_verdict(struct sk_buff *skb, const struct nfnl_info *info,
1224                               const struct nlattr * const nfqa[])
1225 {
1226         struct nfnl_queue_net *q = nfnl_queue_pernet(info->net);
1227         u_int16_t queue_num = ntohs(info->nfmsg->res_id);
1228         const struct nfnl_ct_hook *nfnl_ct;
1229         struct nfqnl_msg_verdict_hdr *vhdr;
1230         enum ip_conntrack_info ctinfo;
1231         struct nfqnl_instance *queue;
1232         struct nf_queue_entry *entry;
1233         struct nf_conn *ct = NULL;
1234         unsigned int verdict;
1235         int err;
1236
1237         queue = verdict_instance_lookup(q, queue_num,
1238                                         NETLINK_CB(skb).portid);
1239         if (IS_ERR(queue))
1240                 return PTR_ERR(queue);
1241
1242         vhdr = verdicthdr_get(nfqa);
1243         if (!vhdr)
1244                 return -EINVAL;
1245
1246         verdict = ntohl(vhdr->verdict);
1247
1248         entry = find_dequeue_entry(queue, ntohl(vhdr->id));
1249         if (entry == NULL)
1250                 return -ENOENT;
1251
1252         /* rcu lock already held from nfnl->call_rcu. */
1253         nfnl_ct = rcu_dereference(nfnl_ct_hook);
1254
1255         if (nfqa[NFQA_CT]) {
1256                 if (nfnl_ct != NULL)
1257                         ct = nfqnl_ct_parse(nfnl_ct, info->nlh, nfqa, entry,
1258                                             &ctinfo);
1259         }
1260
1261         if (entry->state.pf == PF_BRIDGE) {
1262                 err = nfqa_parse_bridge(entry, nfqa);
1263                 if (err < 0)
1264                         return err;
1265         }
1266
1267         if (nfqa[NFQA_PAYLOAD]) {
1268                 u16 payload_len = nla_len(nfqa[NFQA_PAYLOAD]);
1269                 int diff = payload_len - entry->skb->len;
1270
1271                 if (nfqnl_mangle(nla_data(nfqa[NFQA_PAYLOAD]),
1272                                  payload_len, entry, diff) < 0)
1273                         verdict = NF_DROP;
1274
1275                 if (ct && diff)
1276                         nfnl_ct->seq_adjust(entry->skb, ct, ctinfo, diff);
1277         }
1278
1279         if (nfqa[NFQA_MARK])
1280                 entry->skb->mark = ntohl(nla_get_be32(nfqa[NFQA_MARK]));
1281
1282         if (nfqa[NFQA_PRIORITY])
1283                 entry->skb->priority = ntohl(nla_get_be32(nfqa[NFQA_PRIORITY]));
1284
1285         nfqnl_reinject(entry, verdict);
1286         return 0;
1287 }
1288
1289 static int nfqnl_recv_unsupp(struct sk_buff *skb, const struct nfnl_info *info,
1290                              const struct nlattr * const cda[])
1291 {
1292         return -ENOTSUPP;
1293 }
1294
1295 static const struct nla_policy nfqa_cfg_policy[NFQA_CFG_MAX+1] = {
1296         [NFQA_CFG_CMD]          = { .len = sizeof(struct nfqnl_msg_config_cmd) },
1297         [NFQA_CFG_PARAMS]       = { .len = sizeof(struct nfqnl_msg_config_params) },
1298         [NFQA_CFG_QUEUE_MAXLEN] = { .type = NLA_U32 },
1299         [NFQA_CFG_MASK]         = { .type = NLA_U32 },
1300         [NFQA_CFG_FLAGS]        = { .type = NLA_U32 },
1301 };
1302
1303 static const struct nf_queue_handler nfqh = {
1304         .outfn          = nfqnl_enqueue_packet,
1305         .nf_hook_drop   = nfqnl_nf_hook_drop,
1306 };
1307
1308 static int nfqnl_recv_config(struct sk_buff *skb, const struct nfnl_info *info,
1309                              const struct nlattr * const nfqa[])
1310 {
1311         struct nfnl_queue_net *q = nfnl_queue_pernet(info->net);
1312         u_int16_t queue_num = ntohs(info->nfmsg->res_id);
1313         struct nfqnl_msg_config_cmd *cmd = NULL;
1314         struct nfqnl_instance *queue;
1315         __u32 flags = 0, mask = 0;
1316         int ret = 0;
1317
1318         if (nfqa[NFQA_CFG_CMD]) {
1319                 cmd = nla_data(nfqa[NFQA_CFG_CMD]);
1320
1321                 /* Obsolete commands without queue context */
1322                 switch (cmd->command) {
1323                 case NFQNL_CFG_CMD_PF_BIND: return 0;
1324                 case NFQNL_CFG_CMD_PF_UNBIND: return 0;
1325                 }
1326         }
1327
1328         /* Check if we support these flags in first place, dependencies should
1329          * be there too not to break atomicity.
1330          */
1331         if (nfqa[NFQA_CFG_FLAGS]) {
1332                 if (!nfqa[NFQA_CFG_MASK]) {
1333                         /* A mask is needed to specify which flags are being
1334                          * changed.
1335                          */
1336                         return -EINVAL;
1337                 }
1338
1339                 flags = ntohl(nla_get_be32(nfqa[NFQA_CFG_FLAGS]));
1340                 mask = ntohl(nla_get_be32(nfqa[NFQA_CFG_MASK]));
1341
1342                 if (flags >= NFQA_CFG_F_MAX)
1343                         return -EOPNOTSUPP;
1344
1345 #if !IS_ENABLED(CONFIG_NETWORK_SECMARK)
1346                 if (flags & mask & NFQA_CFG_F_SECCTX)
1347                         return -EOPNOTSUPP;
1348 #endif
1349                 if ((flags & mask & NFQA_CFG_F_CONNTRACK) &&
1350                     !rcu_access_pointer(nfnl_ct_hook)) {
1351 #ifdef CONFIG_MODULES
1352                         nfnl_unlock(NFNL_SUBSYS_QUEUE);
1353                         request_module("ip_conntrack_netlink");
1354                         nfnl_lock(NFNL_SUBSYS_QUEUE);
1355                         if (rcu_access_pointer(nfnl_ct_hook))
1356                                 return -EAGAIN;
1357 #endif
1358                         return -EOPNOTSUPP;
1359                 }
1360         }
1361
1362         rcu_read_lock();
1363         queue = instance_lookup(q, queue_num);
1364         if (queue && queue->peer_portid != NETLINK_CB(skb).portid) {
1365                 ret = -EPERM;
1366                 goto err_out_unlock;
1367         }
1368
1369         if (cmd != NULL) {
1370                 switch (cmd->command) {
1371                 case NFQNL_CFG_CMD_BIND:
1372                         if (queue) {
1373                                 ret = -EBUSY;
1374                                 goto err_out_unlock;
1375                         }
1376                         queue = instance_create(q, queue_num,
1377                                                 NETLINK_CB(skb).portid);
1378                         if (IS_ERR(queue)) {
1379                                 ret = PTR_ERR(queue);
1380                                 goto err_out_unlock;
1381                         }
1382                         break;
1383                 case NFQNL_CFG_CMD_UNBIND:
1384                         if (!queue) {
1385                                 ret = -ENODEV;
1386                                 goto err_out_unlock;
1387                         }
1388                         instance_destroy(q, queue);
1389                         goto err_out_unlock;
1390                 case NFQNL_CFG_CMD_PF_BIND:
1391                 case NFQNL_CFG_CMD_PF_UNBIND:
1392                         break;
1393                 default:
1394                         ret = -ENOTSUPP;
1395                         goto err_out_unlock;
1396                 }
1397         }
1398
1399         if (!queue) {
1400                 ret = -ENODEV;
1401                 goto err_out_unlock;
1402         }
1403
1404         if (nfqa[NFQA_CFG_PARAMS]) {
1405                 struct nfqnl_msg_config_params *params =
1406                         nla_data(nfqa[NFQA_CFG_PARAMS]);
1407
1408                 nfqnl_set_mode(queue, params->copy_mode,
1409                                 ntohl(params->copy_range));
1410         }
1411
1412         if (nfqa[NFQA_CFG_QUEUE_MAXLEN]) {
1413                 __be32 *queue_maxlen = nla_data(nfqa[NFQA_CFG_QUEUE_MAXLEN]);
1414
1415                 spin_lock_bh(&queue->lock);
1416                 queue->queue_maxlen = ntohl(*queue_maxlen);
1417                 spin_unlock_bh(&queue->lock);
1418         }
1419
1420         if (nfqa[NFQA_CFG_FLAGS]) {
1421                 spin_lock_bh(&queue->lock);
1422                 queue->flags &= ~mask;
1423                 queue->flags |= flags & mask;
1424                 spin_unlock_bh(&queue->lock);
1425         }
1426
1427 err_out_unlock:
1428         rcu_read_unlock();
1429         return ret;
1430 }
1431
1432 static const struct nfnl_callback nfqnl_cb[NFQNL_MSG_MAX] = {
1433         [NFQNL_MSG_PACKET]      = {
1434                 .call           = nfqnl_recv_unsupp,
1435                 .type           = NFNL_CB_RCU,
1436                 .attr_count     = NFQA_MAX,
1437         },
1438         [NFQNL_MSG_VERDICT]     = {
1439                 .call           = nfqnl_recv_verdict,
1440                 .type           = NFNL_CB_RCU,
1441                 .attr_count     = NFQA_MAX,
1442                 .policy         = nfqa_verdict_policy
1443         },
1444         [NFQNL_MSG_CONFIG]      = {
1445                 .call           = nfqnl_recv_config,
1446                 .type           = NFNL_CB_MUTEX,
1447                 .attr_count     = NFQA_CFG_MAX,
1448                 .policy         = nfqa_cfg_policy
1449         },
1450         [NFQNL_MSG_VERDICT_BATCH] = {
1451                 .call           = nfqnl_recv_verdict_batch,
1452                 .type           = NFNL_CB_RCU,
1453                 .attr_count     = NFQA_MAX,
1454                 .policy         = nfqa_verdict_batch_policy
1455         },
1456 };
1457
1458 static const struct nfnetlink_subsystem nfqnl_subsys = {
1459         .name           = "nf_queue",
1460         .subsys_id      = NFNL_SUBSYS_QUEUE,
1461         .cb_count       = NFQNL_MSG_MAX,
1462         .cb             = nfqnl_cb,
1463 };
1464
1465 #ifdef CONFIG_PROC_FS
1466 struct iter_state {
1467         struct seq_net_private p;
1468         unsigned int bucket;
1469 };
1470
1471 static struct hlist_node *get_first(struct seq_file *seq)
1472 {
1473         struct iter_state *st = seq->private;
1474         struct net *net;
1475         struct nfnl_queue_net *q;
1476
1477         if (!st)
1478                 return NULL;
1479
1480         net = seq_file_net(seq);
1481         q = nfnl_queue_pernet(net);
1482         for (st->bucket = 0; st->bucket < INSTANCE_BUCKETS; st->bucket++) {
1483                 if (!hlist_empty(&q->instance_table[st->bucket]))
1484                         return q->instance_table[st->bucket].first;
1485         }
1486         return NULL;
1487 }
1488
1489 static struct hlist_node *get_next(struct seq_file *seq, struct hlist_node *h)
1490 {
1491         struct iter_state *st = seq->private;
1492         struct net *net = seq_file_net(seq);
1493
1494         h = h->next;
1495         while (!h) {
1496                 struct nfnl_queue_net *q;
1497
1498                 if (++st->bucket >= INSTANCE_BUCKETS)
1499                         return NULL;
1500
1501                 q = nfnl_queue_pernet(net);
1502                 h = q->instance_table[st->bucket].first;
1503         }
1504         return h;
1505 }
1506
1507 static struct hlist_node *get_idx(struct seq_file *seq, loff_t pos)
1508 {
1509         struct hlist_node *head;
1510         head = get_first(seq);
1511
1512         if (head)
1513                 while (pos && (head = get_next(seq, head)))
1514                         pos--;
1515         return pos ? NULL : head;
1516 }
1517
1518 static void *seq_start(struct seq_file *s, loff_t *pos)
1519         __acquires(nfnl_queue_pernet(seq_file_net(s))->instances_lock)
1520 {
1521         spin_lock(&nfnl_queue_pernet(seq_file_net(s))->instances_lock);
1522         return get_idx(s, *pos);
1523 }
1524
1525 static void *seq_next(struct seq_file *s, void *v, loff_t *pos)
1526 {
1527         (*pos)++;
1528         return get_next(s, v);
1529 }
1530
1531 static void seq_stop(struct seq_file *s, void *v)
1532         __releases(nfnl_queue_pernet(seq_file_net(s))->instances_lock)
1533 {
1534         spin_unlock(&nfnl_queue_pernet(seq_file_net(s))->instances_lock);
1535 }
1536
1537 static int seq_show(struct seq_file *s, void *v)
1538 {
1539         const struct nfqnl_instance *inst = v;
1540
1541         seq_printf(s, "%5u %6u %5u %1u %5u %5u %5u %8u %2d\n",
1542                    inst->queue_num,
1543                    inst->peer_portid, inst->queue_total,
1544                    inst->copy_mode, inst->copy_range,
1545                    inst->queue_dropped, inst->queue_user_dropped,
1546                    inst->id_sequence, 1);
1547         return 0;
1548 }
1549
1550 static const struct seq_operations nfqnl_seq_ops = {
1551         .start  = seq_start,
1552         .next   = seq_next,
1553         .stop   = seq_stop,
1554         .show   = seq_show,
1555 };
1556 #endif /* PROC_FS */
1557
1558 static int __net_init nfnl_queue_net_init(struct net *net)
1559 {
1560         unsigned int i;
1561         struct nfnl_queue_net *q = nfnl_queue_pernet(net);
1562
1563         for (i = 0; i < INSTANCE_BUCKETS; i++)
1564                 INIT_HLIST_HEAD(&q->instance_table[i]);
1565
1566         spin_lock_init(&q->instances_lock);
1567
1568 #ifdef CONFIG_PROC_FS
1569         if (!proc_create_net("nfnetlink_queue", 0440, net->nf.proc_netfilter,
1570                         &nfqnl_seq_ops, sizeof(struct iter_state)))
1571                 return -ENOMEM;
1572 #endif
1573         return 0;
1574 }
1575
1576 static void __net_exit nfnl_queue_net_exit(struct net *net)
1577 {
1578         struct nfnl_queue_net *q = nfnl_queue_pernet(net);
1579         unsigned int i;
1580
1581 #ifdef CONFIG_PROC_FS
1582         remove_proc_entry("nfnetlink_queue", net->nf.proc_netfilter);
1583 #endif
1584         for (i = 0; i < INSTANCE_BUCKETS; i++)
1585                 WARN_ON_ONCE(!hlist_empty(&q->instance_table[i]));
1586 }
1587
1588 static struct pernet_operations nfnl_queue_net_ops = {
1589         .init           = nfnl_queue_net_init,
1590         .exit           = nfnl_queue_net_exit,
1591         .id             = &nfnl_queue_net_id,
1592         .size           = sizeof(struct nfnl_queue_net),
1593 };
1594
1595 static int __init nfnetlink_queue_init(void)
1596 {
1597         int status;
1598
1599         status = register_pernet_subsys(&nfnl_queue_net_ops);
1600         if (status < 0) {
1601                 pr_err("failed to register pernet ops\n");
1602                 goto out;
1603         }
1604
1605         netlink_register_notifier(&nfqnl_rtnl_notifier);
1606         status = nfnetlink_subsys_register(&nfqnl_subsys);
1607         if (status < 0) {
1608                 pr_err("failed to create netlink socket\n");
1609                 goto cleanup_netlink_notifier;
1610         }
1611
1612         status = register_netdevice_notifier(&nfqnl_dev_notifier);
1613         if (status < 0) {
1614                 pr_err("failed to register netdevice notifier\n");
1615                 goto cleanup_netlink_subsys;
1616         }
1617
1618         nf_register_queue_handler(&nfqh);
1619
1620         return status;
1621
1622 cleanup_netlink_subsys:
1623         nfnetlink_subsys_unregister(&nfqnl_subsys);
1624 cleanup_netlink_notifier:
1625         netlink_unregister_notifier(&nfqnl_rtnl_notifier);
1626         unregister_pernet_subsys(&nfnl_queue_net_ops);
1627 out:
1628         return status;
1629 }
1630
1631 static void __exit nfnetlink_queue_fini(void)
1632 {
1633         nf_unregister_queue_handler();
1634         unregister_netdevice_notifier(&nfqnl_dev_notifier);
1635         nfnetlink_subsys_unregister(&nfqnl_subsys);
1636         netlink_unregister_notifier(&nfqnl_rtnl_notifier);
1637         unregister_pernet_subsys(&nfnl_queue_net_ops);
1638
1639         rcu_barrier(); /* Wait for completion of call_rcu()'s */
1640 }
1641
1642 MODULE_DESCRIPTION("netfilter packet queue handler");
1643 MODULE_AUTHOR("Harald Welte <laforge@netfilter.org>");
1644 MODULE_LICENSE("GPL");
1645 MODULE_ALIAS_NFNL_SUBSYS(NFNL_SUBSYS_QUEUE);
1646
1647 module_init(nfnetlink_queue_init);
1648 module_exit(nfnetlink_queue_fini);