net/ipv4/netfilter/ip_queue.c

   1 /*
   2  * This is a module which is used for queueing IPv4 packets and
   3  * communicating with userspace via netlink.
   4  *
   5  * (C) 2000-2002 James Morris <jmorris@intercode.com.au>
   6  *
   7  * This program is free software; you can redistribute it and/or modify
   8  * it under the terms of the GNU General Public License version 2 as
   9  * published by the Free Software Foundation.
  10  *
  11  * 2000-03-27: Simplified code (thanks to Andi Kleen for clues).
  12  * 2000-05-20: Fixed notifier problems (following Miguel Freitas' report).
  13  * 2000-06-19: Fixed so nfmark is copied to metadata (reported by Sebastian
  14  *             Zander).
  15  * 2000-08-01: Added Nick Williams' MAC support.
  16  * 2002-06-25: Code cleanup.
  17  *
  18  */
  19 #include <linux/module.h>
  20 #include <linux/skbuff.h>
  21 #include <linux/init.h>
  22 #include <linux/ip.h>
  23 #include <linux/notifier.h>
  24 #include <linux/netdevice.h>
  25 #include <linux/netfilter.h>
  26 #include <linux/netfilter_ipv4/ip_queue.h>
  27 #include <linux/netfilter_ipv4/ip_tables.h>
  28 #include <linux/netlink.h>
  29 #include <linux/spinlock.h>
  30 #include <linux/sysctl.h>
  31 #include <linux/proc_fs.h>
  32 #include <linux/security.h>
  33 #include <net/sock.h>
  34 #include <net/route.h>
  35
  36 #define IPQ_QMAX_DEFAULT 1024
  37 #define IPQ_PROC_FS_NAME "ip_queue"
  38 #define NET_IPQ_QMAX 2088
  39 #define NET_IPQ_QMAX_NAME "ip_queue_maxlen"
  40
  41 struct ipq_rt_info {
  42         __u8 tos;
  43         __u32 daddr;
  44         __u32 saddr;
  45 };
  46
  47 struct ipq_queue_entry {
  48         struct list_head list;
  49         struct nf_info *info;
  50         struct sk_buff *skb;
  51         struct ipq_rt_info rt_info;
  52 };
  53
  54 typedef int (*ipq_cmpfn)(struct ipq_queue_entry *, unsigned long);
  55
  56 static unsigned char copy_mode = IPQ_COPY_NONE;
  57 static unsigned int queue_maxlen = IPQ_QMAX_DEFAULT;
  58 static rwlock_t queue_lock = RW_LOCK_UNLOCKED;
  59 static int peer_pid;
  60 static unsigned int copy_range;
  61 static unsigned int queue_total;
  62 static struct sock *ipqnl;
  63 static LIST_HEAD(queue_list);
  64 static DECLARE_MUTEX(ipqnl_sem);
  65
  66 static void
  67 ipq_issue_verdict(struct ipq_queue_entry *entry, int verdict)
  68 {
  69         nf_reinject(entry->skb, entry->info, verdict);
  70         kfree(entry);
  71 }
  72
  73 static inline int
  74 __ipq_enqueue_entry(struct ipq_queue_entry *entry)
  75 {
  76        if (queue_total >= queue_maxlen) {
  77                if (net_ratelimit())
  78                        printk(KERN_WARNING "ip_queue: full at %d entries, "
  79                               "dropping packet(s).\n", queue_total);
  80                return -ENOSPC;
  81        }
  82        list_add(&entry->list, &queue_list);
  83        queue_total++;
  84        return 0;
  85 }
  86
  87 /*
  88  * Find and return a queued entry matched by cmpfn, or return the last
  89  * entry if cmpfn is NULL.
  90  */
  91 static inline struct ipq_queue_entry *
  92 __ipq_find_entry(ipq_cmpfn cmpfn, unsigned long data)
  93 {
  94         struct list_head *p;
  95
  96         list_for_each_prev(p, &queue_list) {
  97                 struct ipq_queue_entry *entry = (struct ipq_queue_entry *)p;
  98
  99                 if (!cmpfn || cmpfn(entry, data))
 100                         return entry;
 101         }
 102         return NULL;
 103 }
 104
 105 static inline void
 106 __ipq_dequeue_entry(struct ipq_queue_entry *entry)
 107 {
 108         list_del(&entry->list);
 109         queue_total--;
 110 }
 111
 112 static inline struct ipq_queue_entry *
 113 __ipq_find_dequeue_entry(ipq_cmpfn cmpfn, unsigned long data)
 114 {
 115         struct ipq_queue_entry *entry;
 116
 117         entry = __ipq_find_entry(cmpfn, data);
 118         if (entry == NULL)
 119                 return NULL;
 120
 121         __ipq_dequeue_entry(entry);
 122         return entry;
 123 }
 124
 125
 126 static inline void
 127 __ipq_flush(int verdict)
 128 {
 129         struct ipq_queue_entry *entry;
 130
 131         while ((entry = __ipq_find_dequeue_entry(NULL, 0)))
 132                 ipq_issue_verdict(entry, verdict);
 133 }
 134
 135 static inline int
 136 __ipq_set_mode(unsigned char mode, unsigned int range)
 137 {
 138         int status = 0;
 139
 140         switch(mode) {
 141         case IPQ_COPY_NONE:
 142         case IPQ_COPY_META:
 143                 copy_mode = mode;
 144                 copy_range = 0;
 145                 break;
 146
 147         case IPQ_COPY_PACKET:
 148                 copy_mode = mode;
 149                 copy_range = range;
 150                 if (copy_range > 0xFFFF)
 151                         copy_range = 0xFFFF;
 152                 break;
 153
 154         default:
 155                 status = -EINVAL;
 156
 157         }
 158         return status;
 159 }
 160
 161 static inline void
 162 __ipq_reset(void)
 163 {
 164         peer_pid = 0;
 165         __ipq_set_mode(IPQ_COPY_NONE, 0);
 166         __ipq_flush(NF_DROP);
 167 }
 168
 169 static struct ipq_queue_entry *
 170 ipq_find_dequeue_entry(ipq_cmpfn cmpfn, unsigned long data)
 171 {
 172         struct ipq_queue_entry *entry;
 173
 174         write_lock_bh(&queue_lock);
 175         entry = __ipq_find_dequeue_entry(cmpfn, data);
 176         write_unlock_bh(&queue_lock);
 177         return entry;
 178 }
 179
 180 static void
 181 ipq_flush(int verdict)
 182 {
 183         write_lock_bh(&queue_lock);
 184         __ipq_flush(verdict);
 185         write_unlock_bh(&queue_lock);
 186 }
 187
 188 static struct sk_buff *
 189 ipq_build_packet_message(struct ipq_queue_entry *entry, int *errp)
 190 {
 191         unsigned char *old_tail;
 192         size_t size = 0;
 193         size_t data_len = 0;
 194         struct sk_buff *skb;
 195         struct ipq_packet_msg *pmsg;
 196         struct nlmsghdr *nlh;
 197
 198         read_lock_bh(&queue_lock);
 199
 200         switch (copy_mode) {
 201         case IPQ_COPY_META:
 202         case IPQ_COPY_NONE:
 203                 size = NLMSG_SPACE(sizeof(*pmsg));
 204                 data_len = 0;
 205                 break;
 206
 207         case IPQ_COPY_PACKET:
 208                 if (copy_range == 0 || copy_range > entry->skb->len)
 209                         data_len = entry->skb->len;
 210                 else
 211                         data_len = copy_range;
 212
 213                 size = NLMSG_SPACE(sizeof(*pmsg) + data_len);
 214                 break;
 215
 216         default:
 217                 *errp = -EINVAL;
 218                 read_unlock_bh(&queue_lock);
 219                 return NULL;
 220         }
 221
 222         read_unlock_bh(&queue_lock);
 223
 224         skb = alloc_skb(size, GFP_ATOMIC);
 225         if (!skb)
 226                 goto nlmsg_failure;
 227
 228         old_tail= skb->tail;
 229         nlh = NLMSG_PUT(skb, 0, 0, IPQM_PACKET, size - sizeof(*nlh));
 230         pmsg = NLMSG_DATA(nlh);
 231         memset(pmsg, 0, sizeof(*pmsg));
 232
 233         pmsg->packet_id       = (unsigned long )entry;
 234         pmsg->data_len        = data_len;
 235         pmsg->timestamp_sec   = entry->skb->stamp.tv_sec;
 236         pmsg->timestamp_usec  = entry->skb->stamp.tv_usec;
 237         pmsg->mark            = entry->skb->nfmark;
 238         pmsg->hook            = entry->info->hook;
 239         pmsg->hw_protocol     = entry->skb->protocol;
 240
 241         if (entry->info->indev)
 242                 strcpy(pmsg->indev_name, entry->info->indev->name);
 243         else
 244                 pmsg->indev_name[0] = '\0';
 245
 246         if (entry->info->outdev)
 247                 strcpy(pmsg->outdev_name, entry->info->outdev->name);
 248         else
 249                 pmsg->outdev_name[0] = '\0';
 250
 251         if (entry->info->indev && entry->skb->dev) {
 252                 pmsg->hw_type = entry->skb->dev->type;
 253                 if (entry->skb->dev->hard_header_parse)
 254                         pmsg->hw_addrlen =
 255                                 entry->skb->dev->hard_header_parse(entry->skb,
 256                                                                    pmsg->hw_addr);
 257         }
 258
 259         if (data_len)
 260                 memcpy(pmsg->payload, entry->skb->data, data_len);
 261
 262         nlh->nlmsg_len = skb->tail - old_tail;
 263         return skb;
 264
 265 nlmsg_failure:
 266         if (skb)
 267                 kfree_skb(skb);
 268         *errp = -EINVAL;
 269         printk(KERN_ERR "ip_queue: error creating packet message\n");
 270         return NULL;
 271 }
 272
 273 static int
 274 ipq_enqueue_packet(struct sk_buff *skb, struct nf_info *info, void *data)
 275 {
 276         int status = -EINVAL;
 277         struct sk_buff *nskb;
 278         struct ipq_queue_entry *entry;
 279
 280         if (copy_mode == IPQ_COPY_NONE)
 281                 return -EAGAIN;
 282
 283         entry = kmalloc(sizeof(*entry), GFP_ATOMIC);
 284         if (entry == NULL) {
 285                 printk(KERN_ERR "ip_queue: OOM in ipq_enqueue_packet()\n");
 286                 return -ENOMEM;
 287         }
 288
 289         entry->info = info;
 290         entry->skb = skb;
 291
 292         if (entry->info->hook == NF_IP_LOCAL_OUT) {
 293                 struct iphdr *iph = skb->nh.iph;
 294
 295                 entry->rt_info.tos = iph->tos;
 296                 entry->rt_info.daddr = iph->daddr;
 297                 entry->rt_info.saddr = iph->saddr;
 298         }
 299
 300         nskb = ipq_build_packet_message(entry, &status);
 301         if (nskb == NULL)
 302                 goto err_out_free;
 303
 304         write_lock_bh(&queue_lock);
 305
 306         if (!peer_pid)
 307                 goto err_out_free_nskb;
 308
 309         /* netlink_unicast will either free the nskb or attach it to a socket */
 310         status = netlink_unicast(ipqnl, nskb, peer_pid, MSG_DONTWAIT);
 311         if (status < 0)
 312                 goto err_out_unlock;
 313
 314         status = __ipq_enqueue_entry(entry);
 315         if (status < 0)
 316                 goto err_out_unlock;
 317
 318         write_unlock_bh(&queue_lock);
 319         return status;
 320
 321 err_out_free_nskb:
 322         kfree_skb(nskb);
 323
 324 err_out_unlock:
 325         write_unlock_bh(&queue_lock);
 326
 327 err_out_free:
 328         kfree(entry);
 329         return status;
 330 }
 331
 332 static int
 333 ipq_mangle_ipv4(ipq_verdict_msg_t *v, struct ipq_queue_entry *e)
 334 {
 335         int diff;
 336         struct iphdr *user_iph = (struct iphdr *)v->payload;
 337
 338         if (v->data_len < sizeof(*user_iph))
 339                 return 0;
 340         diff = v->data_len - e->skb->len;
 341         if (diff < 0)
 342                 skb_trim(e->skb, v->data_len);
 343         else if (diff > 0) {
 344                 if (v->data_len > 0xFFFF)
 345                         return -EINVAL;
 346                 if (diff > skb_tailroom(e->skb)) {
 347                         struct sk_buff *newskb;
 348
 349                         newskb = skb_copy_expand(e->skb,
 350                                                  skb_headroom(e->skb),
 351                                                  diff,
 352                                                  GFP_ATOMIC);
 353                         if (newskb == NULL) {
 354                                 printk(KERN_WARNING "ip_queue: OOM "
 355                                       "in mangle, dropping packet\n");
 356                                 return -ENOMEM;
 357                         }
 358                         if (e->skb->sk)
 359                                 skb_set_owner_w(newskb, e->skb->sk);
 360                         kfree_skb(e->skb);
 361                         e->skb = newskb;
 362                 }
 363                 skb_put(e->skb, diff);
 364         }
 365         memcpy(e->skb->data, v->payload, v->data_len);
 366         e->skb->nfcache |= NFC_ALTERED;
 367
 368         /*
 369          * Extra routing may needed on local out, as the QUEUE target never
 370          * returns control to the table.
 371          */
 372         if (e->info->hook == NF_IP_LOCAL_OUT) {
 373                 struct iphdr *iph = e->skb->nh.iph;
 374
 375                 if (!(iph->tos == e->rt_info.tos
 376                       && iph->daddr == e->rt_info.daddr
 377                       && iph->saddr == e->rt_info.saddr))
 378                         return ip_route_me_harder(&e->skb);
 379         }
 380         return 0;
 381 }
 382
 383 static inline int
 384 id_cmp(struct ipq_queue_entry *e, unsigned long id)
 385 {
 386         return (id == (unsigned long )e);
 387 }
 388
 389 static int
 390 ipq_set_verdict(struct ipq_verdict_msg *vmsg, unsigned int len)
 391 {
 392         struct ipq_queue_entry *entry;
 393
 394         if (vmsg->value > NF_MAX_VERDICT)
 395                 return -EINVAL;
 396
 397         entry = ipq_find_dequeue_entry(id_cmp, vmsg->id);
 398         if (entry == NULL)
 399                 return -ENOENT;
 400         else {
 401                 int verdict = vmsg->value;
 402
 403                 if (vmsg->data_len && vmsg->data_len == len)
 404                         if (ipq_mangle_ipv4(vmsg, entry) < 0)
 405                                 verdict = NF_DROP;
 406
 407                 ipq_issue_verdict(entry, verdict);
 408                 return 0;
 409         }
 410 }
 411
 412 static int
 413 ipq_set_mode(unsigned char mode, unsigned int range)
 414 {
 415         int status;
 416
 417         write_lock_bh(&queue_lock);
 418         status = __ipq_set_mode(mode, range);
 419         write_unlock_bh(&queue_lock);
 420         return status;
 421 }
 422
 423 static int
 424 ipq_receive_peer(struct ipq_peer_msg *pmsg,
 425                  unsigned char type, unsigned int len)
 426 {
 427         int status = 0;
 428
 429         if (len < sizeof(*pmsg))
 430                 return -EINVAL;
 431
 432         switch (type) {
 433         case IPQM_MODE:
 434                 status = ipq_set_mode(pmsg->msg.mode.value,
 435                                       pmsg->msg.mode.range);
 436                 break;
 437
 438         case IPQM_VERDICT:
 439                 if (pmsg->msg.verdict.value > NF_MAX_VERDICT)
 440                         status = -EINVAL;
 441                 else
 442                         status = ipq_set_verdict(&pmsg->msg.verdict,
 443                                                  len - sizeof(*pmsg));
 444                         break;
 445         default:
 446                 status = -EINVAL;
 447         }
 448         return status;
 449 }
 450
 451 static int
 452 dev_cmp(struct ipq_queue_entry *entry, unsigned long ifindex)
 453 {
 454         if (entry->info->indev)
 455                 if (entry->info->indev->ifindex == ifindex)
 456                         return 1;
 457
 458         if (entry->info->outdev)
 459                 if (entry->info->outdev->ifindex == ifindex)
 460                         return 1;
 461
 462         return 0;
 463 }
 464
 465 static void
 466 ipq_dev_drop(int ifindex)
 467 {
 468         struct ipq_queue_entry *entry;
 469
 470         while ((entry = ipq_find_dequeue_entry(dev_cmp, ifindex)) != NULL)
 471                 ipq_issue_verdict(entry, NF_DROP);
 472 }
 473
 474 #define RCV_SKB_FAIL(err) do { netlink_ack(skb, nlh, (err)); return; } while (0)
 475
 476 static inline void
 477 ipq_rcv_skb(struct sk_buff *skb)
 478 {
 479         int status, type, pid, flags, nlmsglen, skblen;
 480         struct nlmsghdr *nlh;
 481
 482         skblen = skb->len;
 483         if (skblen < sizeof(*nlh))
 484                 return;
 485
 486         nlh = (struct nlmsghdr *)skb->data;
 487         nlmsglen = nlh->nlmsg_len;
 488         if (nlmsglen < sizeof(*nlh) || skblen < nlmsglen)
 489                 return;
 490
 491         pid = nlh->nlmsg_pid;
 492         flags = nlh->nlmsg_flags;
 493
 494         if(pid <= 0 || !(flags & NLM_F_REQUEST) || flags & NLM_F_MULTI)
 495                 RCV_SKB_FAIL(-EINVAL);
 496
 497         if (flags & MSG_TRUNC)
 498                 RCV_SKB_FAIL(-ECOMM);
 499
 500         type = nlh->nlmsg_type;
 501         if (type < NLMSG_NOOP || type >= IPQM_MAX)
 502                 RCV_SKB_FAIL(-EINVAL);
 503
 504         if (type <= IPQM_BASE)
 505                 return;
 506
 507         if (security_netlink_recv(skb))
 508                 RCV_SKB_FAIL(-EPERM);
 509
 510         write_lock_bh(&queue_lock);
 511
 512         if (peer_pid) {
 513                 if (peer_pid != pid) {
 514                         write_unlock_bh(&queue_lock);
 515                         RCV_SKB_FAIL(-EBUSY);
 516                 }
 517         }
 518         else
 519                 peer_pid = pid;
 520
 521         write_unlock_bh(&queue_lock);
 522
 523         status = ipq_receive_peer(NLMSG_DATA(nlh), type,
 524                                   skblen - NLMSG_LENGTH(0));
 525         if (status < 0)
 526                 RCV_SKB_FAIL(status);
 527
 528         if (flags & NLM_F_ACK)
 529                 netlink_ack(skb, nlh, 0);
 530         return;
 531 }
 532
 533 static void
 534 ipq_rcv_sk(struct sock *sk, int len)
 535 {
 536         do {
 537                 struct sk_buff *skb;
 538
 539                 if (down_trylock(&ipqnl_sem))
 540                         return;
 541
 542                 while ((skb = skb_dequeue(&sk->sk_receive_queue)) != NULL) {
 543                         ipq_rcv_skb(skb);
 544                         kfree_skb(skb);
 545                 }
 546
 547                 up(&ipqnl_sem);
 548
 549         } while (ipqnl && ipqnl->sk_receive_queue.qlen);
 550 }
 551
 552 static int
 553 ipq_rcv_dev_event(struct notifier_block *this,
 554                   unsigned long event, void *ptr)
 555 {
 556         struct net_device *dev = ptr;
 557
 558         /* Drop any packets associated with the downed device */
 559         if (event == NETDEV_DOWN)
 560                 ipq_dev_drop(dev->ifindex);
 561         return NOTIFY_DONE;
 562 }
 563
 564 static struct notifier_block ipq_dev_notifier = {
 565         .notifier_call  = ipq_rcv_dev_event,
 566 };
 567
 568 static int
 569 ipq_rcv_nl_event(struct notifier_block *this,
 570                  unsigned long event, void *ptr)
 571 {
 572         struct netlink_notify *n = ptr;
 573
 574         if (event == NETLINK_URELEASE &&
 575             n->protocol == NETLINK_FIREWALL && n->pid) {
 576                 write_lock_bh(&queue_lock);
 577                 if (n->pid == peer_pid)
 578                         __ipq_reset();
 579                 write_unlock_bh(&queue_lock);
 580         }
 581         return NOTIFY_DONE;
 582 }
 583
 584 static struct notifier_block ipq_nl_notifier = {
 585         .notifier_call  = ipq_rcv_nl_event,
 586 };
 587
 588 static struct ctl_table_header *ipq_sysctl_header;
 589
 590 static ctl_table ipq_table[] = {
 591         {
 592                 .ctl_name       = NET_IPQ_QMAX,
 593                 .procname       = NET_IPQ_QMAX_NAME,
 594                 .data           = &queue_maxlen,
 595                 .maxlen         = sizeof(queue_maxlen),
 596                 .mode           = 0644,
 597                 .proc_handler   = proc_dointvec
 598         },
 599         { .ctl_name = 0 }
 600 };
 601
 602 static ctl_table ipq_dir_table[] = {
 603         {
 604                 .ctl_name       = NET_IPV4,
 605                 .procname       = "ipv4",
 606                 .mode           = 0555,
 607                 .child          = ipq_table
 608         },
 609         { .ctl_name = 0 }
 610 };
 611
 612 static ctl_table ipq_root_table[] = {
 613         {
 614                 .ctl_name       = CTL_NET,
 615                 .procname       = "net",
 616                 .mode           = 0555,
 617                 .child          = ipq_dir_table
 618         },
 619         { .ctl_name = 0 }
 620 };
 621
 622 static int
 623 ipq_get_info(char *buffer, char **start, off_t offset, int length)
 624 {
 625         int len;
 626
 627         read_lock_bh(&queue_lock);
 628
 629         len = sprintf(buffer,
 630                       "Peer PID          : %d\n"
 631                       "Copy mode         : %hu\n"
 632                       "Copy range        : %u\n"
 633                       "Queue length      : %u\n"
 634                       "Queue max. length : %u\n",
 635                       peer_pid,
 636                       copy_mode,
 637                       copy_range,
 638                       queue_total,
 639                       queue_maxlen);
 640
 641         read_unlock_bh(&queue_lock);
 642
 643         *start = buffer + offset;
 644         len -= offset;
 645         if (len > length)
 646                 len = length;
 647         else if (len < 0)
 648                 len = 0;
 649         return len;
 650 }
 651
 652 static int
 653 init_or_cleanup(int init)
 654 {
 655         int status = -ENOMEM;
 656         struct proc_dir_entry *proc;
 657
 658         if (!init)
 659                 goto cleanup;
 660
 661         netlink_register_notifier(&ipq_nl_notifier);
 662         ipqnl = netlink_kernel_create(NETLINK_FIREWALL, ipq_rcv_sk);
 663         if (ipqnl == NULL) {
 664                 printk(KERN_ERR "ip_queue: failed to create netlink socket\n");
 665                 goto cleanup_netlink_notifier;
 666         }
 667
 668         proc = proc_net_create(IPQ_PROC_FS_NAME, 0, ipq_get_info);
 669         if (proc)
 670                 proc->owner = THIS_MODULE;
 671         else {
 672                 printk(KERN_ERR "ip_queue: failed to create proc entry\n");
 673                 goto cleanup_ipqnl;
 674         }
 675
 676         register_netdevice_notifier(&ipq_dev_notifier);
 677         ipq_sysctl_header = register_sysctl_table(ipq_root_table, 0);
 678
 679         status = nf_register_queue_handler(PF_INET, ipq_enqueue_packet, NULL);
 680         if (status < 0) {
 681                 printk(KERN_ERR "ip_queue: failed to register queue handler\n");
 682                 goto cleanup_sysctl;
 683         }
 684         return status;
 685
 686 cleanup:
 687         nf_unregister_queue_handler(PF_INET);
 688         synchronize_net();
 689         ipq_flush(NF_DROP);
 690
 691 cleanup_sysctl:
 692         unregister_sysctl_table(ipq_sysctl_header);
 693         unregister_netdevice_notifier(&ipq_dev_notifier);
 694         proc_net_remove(IPQ_PROC_FS_NAME);
 695
 696 cleanup_ipqnl:
 697         sock_release(ipqnl->sk_socket);
 698         down(&ipqnl_sem);
 699         up(&ipqnl_sem);
 700
 701 cleanup_netlink_notifier:
 702         netlink_unregister_notifier(&ipq_nl_notifier);
 703         return status;
 704 }
 705
 706 static int __init init(void)
 707 {
 708
 709         return init_or_cleanup(1);
 710 }
 711
 712 static void __exit fini(void)
 713 {
 714         init_or_cleanup(0);
 715 }
 716
 717 MODULE_DESCRIPTION("IPv4 packet queue handler");
 718 MODULE_AUTHOR("James Morris <jmorris@intercode.com.au>");
 719 MODULE_LICENSE("GPL");
 720
 721 module_init(init);
 722 module_exit(fini);