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