net/ipv4/netfilter/arp_tables.c

   1 /*
   2  * Packet matching code for ARP packets.
   3  *
   4  * Based heavily, if not almost entirely, upon ip_tables.c framework.
   5  *
   6  * Some ARP specific bits are:
   7  *
   8  * Copyright (C) 2002 David S. Miller (davem@redhat.com)
   9  *
  10  */
  11
  12 #include <linux/config.h>
  13 #include <linux/kernel.h>
  14 #include <linux/skbuff.h>
  15 #include <linux/netdevice.h>
  16 #include <linux/if_arp.h>
  17 #include <linux/kmod.h>
  18 #include <linux/vmalloc.h>
  19 #include <linux/proc_fs.h>
  20 #include <linux/module.h>
  21 #include <linux/init.h>
  22
  23 #include <asm/uaccess.h>
  24 #include <asm/semaphore.h>
  25
  26 #include <linux/netfilter_arp/arp_tables.h>
  27
  28 MODULE_LICENSE("GPL");
  29 MODULE_AUTHOR("David S. Miller <davem@redhat.com>");
  30 MODULE_DESCRIPTION("arptables core");
  31
  32 /*#define DEBUG_ARP_TABLES*/
  33 /*#define DEBUG_ARP_TABLES_USER*/
  34
  35 #ifdef DEBUG_ARP_TABLES
  36 #define dprintf(format, args...)  printk(format , ## args)
  37 #else
  38 #define dprintf(format, args...)
  39 #endif
  40
  41 #ifdef DEBUG_ARP_TABLES_USER
  42 #define duprintf(format, args...) printk(format , ## args)
  43 #else
  44 #define duprintf(format, args...)
  45 #endif
  46
  47 #ifdef CONFIG_NETFILTER_DEBUG
  48 #define ARP_NF_ASSERT(x)                                        \
  49 do {                                                            \
  50         if (!(x))                                               \
  51                 printk("ARP_NF_ASSERT: %s:%s:%u\n",             \
  52                        __FUNCTION__, __FILE__, __LINE__);       \
  53 } while(0)
  54 #else
  55 #define ARP_NF_ASSERT(x)
  56 #endif
  57 #define SMP_ALIGN(x) (((x) + SMP_CACHE_BYTES-1) & ~(SMP_CACHE_BYTES-1))
  58
  59 static DECLARE_MUTEX(arpt_mutex);
  60
  61 #define ASSERT_READ_LOCK(x) ARP_NF_ASSERT(down_trylock(&arpt_mutex) != 0)
  62 #define ASSERT_WRITE_LOCK(x) ARP_NF_ASSERT(down_trylock(&arpt_mutex) != 0)
  63 #include <linux/netfilter_ipv4/lockhelp.h>
  64 #include <linux/netfilter_ipv4/listhelp.h>
  65
  66 struct arpt_table_info {
  67         unsigned int size;
  68         unsigned int number;
  69         unsigned int initial_entries;
  70         unsigned int hook_entry[NF_ARP_NUMHOOKS];
  71         unsigned int underflow[NF_ARP_NUMHOOKS];
  72         char entries[0] __attribute__((aligned(SMP_CACHE_BYTES)));
  73 };
  74
  75 static LIST_HEAD(arpt_target);
  76 static LIST_HEAD(arpt_tables);
  77 #define ADD_COUNTER(c,b,p) do { (c).bcnt += (b); (c).pcnt += (p); } while(0)
  78
  79 #ifdef CONFIG_SMP
  80 #define TABLE_OFFSET(t,p) (SMP_ALIGN((t)->size)*(p))
  81 #else
  82 #define TABLE_OFFSET(t,p) 0
  83 #endif
  84
  85 static inline int arp_devaddr_compare(const struct arpt_devaddr_info *ap,
  86                                       char *hdr_addr, int len)
  87 {
  88         int i, ret;
  89
  90         if (len > ARPT_DEV_ADDR_LEN_MAX)
  91                 len = ARPT_DEV_ADDR_LEN_MAX;
  92
  93         ret = 0;
  94         for (i = 0; i < len; i++)
  95                 ret |= (hdr_addr[i] ^ ap->addr[i]) & ap->mask[i];
  96
  97         return (ret != 0);
  98 }
  99
 100 /* Returns whether packet matches rule or not. */
 101 static inline int arp_packet_match(const struct arphdr *arphdr,
 102                                    struct net_device *dev,
 103                                    const char *indev,
 104                                    const char *outdev,
 105                                    const struct arpt_arp *arpinfo)
 106 {
 107         char *arpptr = (char *)(arphdr + 1);
 108         char *src_devaddr, *tgt_devaddr;
 109         u32 *src_ipaddr, *tgt_ipaddr;
 110         int i, ret;
 111
 112 #define FWINV(bool,invflg) ((bool) ^ !!(arpinfo->invflags & invflg))
 113
 114         if (FWINV((arphdr->ar_op & arpinfo->arpop_mask) != arpinfo->arpop,
 115                   ARPT_INV_ARPOP)) {
 116                 dprintf("ARP operation field mismatch.\n");
 117                 dprintf("ar_op: %04x info->arpop: %04x info->arpop_mask: %04x\n",
 118                         arphdr->ar_op, arpinfo->arpop, arpinfo->arpop_mask);
 119                 return 0;
 120         }
 121
 122         if (FWINV((arphdr->ar_hrd & arpinfo->arhrd_mask) != arpinfo->arhrd,
 123                   ARPT_INV_ARPHRD)) {
 124                 dprintf("ARP hardware address format mismatch.\n");
 125                 dprintf("ar_hrd: %04x info->arhrd: %04x info->arhrd_mask: %04x\n",
 126                         arphdr->ar_hrd, arpinfo->arhrd, arpinfo->arhrd_mask);
 127                 return 0;
 128         }
 129
 130         if (FWINV((arphdr->ar_pro & arpinfo->arpro_mask) != arpinfo->arpro,
 131                   ARPT_INV_ARPPRO)) {
 132                 dprintf("ARP protocol address format mismatch.\n");
 133                 dprintf("ar_pro: %04x info->arpro: %04x info->arpro_mask: %04x\n",
 134                         arphdr->ar_pro, arpinfo->arpro, arpinfo->arpro_mask);
 135                 return 0;
 136         }
 137
 138         if (FWINV((arphdr->ar_hln & arpinfo->arhln_mask) != arpinfo->arhln,
 139                   ARPT_INV_ARPHLN)) {
 140                 dprintf("ARP hardware address length mismatch.\n");
 141                 dprintf("ar_hln: %02x info->arhln: %02x info->arhln_mask: %02x\n",
 142                         arphdr->ar_hln, arpinfo->arhln, arpinfo->arhln_mask);
 143                 return 0;
 144         }
 145
 146         src_devaddr = arpptr;
 147         arpptr += dev->addr_len;
 148         src_ipaddr = (u32 *) arpptr;
 149         arpptr += sizeof(u32);
 150         tgt_devaddr = arpptr;
 151         arpptr += dev->addr_len;
 152         tgt_ipaddr = (u32 *) arpptr;
 153
 154         if (FWINV(arp_devaddr_compare(&arpinfo->src_devaddr, src_devaddr, dev->addr_len),
 155                   ARPT_INV_SRCDEVADDR) ||
 156             FWINV(arp_devaddr_compare(&arpinfo->tgt_devaddr, tgt_devaddr, dev->addr_len),
 157                   ARPT_INV_TGTDEVADDR)) {
 158                 dprintf("Source or target device address mismatch.\n");
 159
 160                 return 0;
 161         }
 162
 163         if (FWINV(((*src_ipaddr) & arpinfo->smsk.s_addr) != arpinfo->src.s_addr,
 164                   ARPT_INV_SRCIP) ||
 165             FWINV((((*tgt_ipaddr) & arpinfo->tmsk.s_addr) != arpinfo->tgt.s_addr),
 166                   ARPT_INV_TGTIP)) {
 167                 dprintf("Source or target IP address mismatch.\n");
 168
 169                 dprintf("SRC: %u.%u.%u.%u. Mask: %u.%u.%u.%u. Target: %u.%u.%u.%u.%s\n",
 170                         NIPQUAD(*src_ipaddr),
 171                         NIPQUAD(arpinfo->smsk.s_addr),
 172                         NIPQUAD(arpinfo->src.s_addr),
 173                         arpinfo->invflags & ARPT_INV_SRCIP ? " (INV)" : "");
 174                 dprintf("TGT: %u.%u.%u.%u Mask: %u.%u.%u.%u Target: %u.%u.%u.%u.%s\n",
 175                         NIPQUAD(*tgt_ipaddr),
 176                         NIPQUAD(arpinfo->tmsk.s_addr),
 177                         NIPQUAD(arpinfo->tgt.s_addr),
 178                         arpinfo->invflags & ARPT_INV_TGTIP ? " (INV)" : "");
 179                 return 0;
 180         }
 181
 182         /* Look for ifname matches.  */
 183         for (i = 0, ret = 0; i < IFNAMSIZ; i++) {
 184                 ret |= (indev[i] ^ arpinfo->iniface[i])
 185                         & arpinfo->iniface_mask[i];
 186         }
 187
 188         if (FWINV(ret != 0, ARPT_INV_VIA_IN)) {
 189                 dprintf("VIA in mismatch (%s vs %s).%s\n",
 190                         indev, arpinfo->iniface,
 191                         arpinfo->invflags&ARPT_INV_VIA_IN ?" (INV)":"");
 192                 return 0;
 193         }
 194
 195         for (i = 0, ret = 0; i < IFNAMSIZ/sizeof(unsigned long); i++) {
 196                 ret |= (((const unsigned long *)outdev)[i]
 197                         ^ ((const unsigned long *)arpinfo->outiface)[i])
 198                         & ((const unsigned long *)arpinfo->outiface_mask)[i];
 199         }
 200
 201         if (FWINV(ret != 0, ARPT_INV_VIA_OUT)) {
 202                 dprintf("VIA out mismatch (%s vs %s).%s\n",
 203                         outdev, arpinfo->outiface,
 204                         arpinfo->invflags&ARPT_INV_VIA_OUT ?" (INV)":"");
 205                 return 0;
 206         }
 207
 208         return 1;
 209 }
 210
 211 static inline int arp_checkentry(const struct arpt_arp *arp)
 212 {
 213         if (arp->flags & ~ARPT_F_MASK) {
 214                 duprintf("Unknown flag bits set: %08X\n",
 215                          arp->flags & ~ARPT_F_MASK);
 216                 return 0;
 217         }
 218         if (arp->invflags & ~ARPT_INV_MASK) {
 219                 duprintf("Unknown invflag bits set: %08X\n",
 220                          arp->invflags & ~ARPT_INV_MASK);
 221                 return 0;
 222         }
 223
 224         return 1;
 225 }
 226
 227 static unsigned int arpt_error(struct sk_buff **pskb,
 228                                unsigned int hooknum,
 229                                const struct net_device *in,
 230                                const struct net_device *out,
 231                                const void *targinfo,
 232                                void *userinfo)
 233 {
 234         if (net_ratelimit())
 235                 printk("arp_tables: error: '%s'\n", (char *)targinfo);
 236
 237         return NF_DROP;
 238 }
 239
 240 static inline struct arpt_entry *get_entry(void *base, unsigned int offset)
 241 {
 242         return (struct arpt_entry *)(base + offset);
 243 }
 244
 245 unsigned int arpt_do_table(struct sk_buff **pskb,
 246                            unsigned int hook,
 247                            const struct net_device *in,
 248                            const struct net_device *out,
 249                            struct arpt_table *table,
 250                            void *userdata)
 251 {
 252         static const char nulldevname[IFNAMSIZ];
 253         unsigned int verdict = NF_DROP;
 254         struct arphdr *arp;
 255         int hotdrop = 0;
 256         struct arpt_entry *e, *back;
 257         const char *indev, *outdev;
 258         void *table_base;
 259
 260         /* ARP header, plus 2 device addresses, plus 2 IP addresses.  */
 261         if (!pskb_may_pull((*pskb), (sizeof(struct arphdr) +
 262                                      (2 * (*pskb)->dev->addr_len) +
 263                                      (2 * sizeof(u32)))))
 264                 return NF_DROP;
 265
 266         indev = in ? in->name : nulldevname;
 267         outdev = out ? out->name : nulldevname;
 268
 269         read_lock_bh(&table->lock);
 270         table_base = (void *)table->private->entries
 271                 + TABLE_OFFSET(table->private,
 272                                smp_processor_id());
 273         e = get_entry(table_base, table->private->hook_entry[hook]);
 274         back = get_entry(table_base, table->private->underflow[hook]);
 275
 276         arp = (*pskb)->nh.arph;
 277         do {
 278                 if (arp_packet_match(arp, (*pskb)->dev, indev, outdev, &e->arp)) {
 279                         struct arpt_entry_target *t;
 280                         int hdr_len;
 281
 282                         hdr_len = sizeof(*arp) + (2 * sizeof(struct in_addr)) +
 283                                 (2 * (*pskb)->dev->addr_len);
 284                         ADD_COUNTER(e->counters, hdr_len, 1);
 285
 286                         t = arpt_get_target(e);
 287
 288                         /* Standard target? */
 289                         if (!t->u.kernel.target->target) {
 290                                 int v;
 291
 292                                 v = ((struct arpt_standard_target *)t)->verdict;
 293                                 if (v < 0) {
 294                                         /* Pop from stack? */
 295                                         if (v != ARPT_RETURN) {
 296                                                 verdict = (unsigned)(-v) - 1;
 297                                                 break;
 298                                         }
 299                                         e = back;
 300                                         back = get_entry(table_base,
 301                                                          back->comefrom);
 302                                         continue;
 303                                 }
 304                                 if (table_base + v
 305                                     != (void *)e + e->next_offset) {
 306                                         /* Save old back ptr in next entry */
 307                                         struct arpt_entry *next
 308                                                 = (void *)e + e->next_offset;
 309                                         next->comefrom =
 310                                                 (void *)back - table_base;
 311
 312                                         /* set back pointer to next entry */
 313                                         back = next;
 314                                 }
 315
 316                                 e = get_entry(table_base, v);
 317                         } else {
 318                                 /* Targets which reenter must return
 319                                  * abs. verdicts
 320                                  */
 321                                 verdict = t->u.kernel.target->target(pskb,
 322                                                                      hook,
 323                                                                      in, out,
 324                                                                      t->data,
 325                                                                      userdata);
 326
 327                                 /* Target might have changed stuff. */
 328                                 arp = (*pskb)->nh.arph;
 329
 330                                 if (verdict == ARPT_CONTINUE)
 331                                         e = (void *)e + e->next_offset;
 332                                 else
 333                                         /* Verdict */
 334                                         break;
 335                         }
 336                 } else {
 337                         e = (void *)e + e->next_offset;
 338                 }
 339         } while (!hotdrop);
 340         read_unlock_bh(&table->lock);
 341
 342         if (hotdrop)
 343                 return NF_DROP;
 344         else
 345                 return verdict;
 346 }
 347
 348 static inline void *find_inlist_lock_noload(struct list_head *head,
 349                                             const char *name,
 350                                             int *error,
 351                                             struct semaphore *mutex)
 352 {
 353         void *ret;
 354
 355         *error = down_interruptible(mutex);
 356         if (*error != 0)
 357                 return NULL;
 358
 359         ret = list_named_find(head, name);
 360         if (!ret) {
 361                 *error = -ENOENT;
 362                 up(mutex);
 363         }
 364         return ret;
 365 }
 366
 367 #ifndef CONFIG_KMOD
 368 #define find_inlist_lock(h,n,p,e,m) find_inlist_lock_noload((h),(n),(e),(m))
 369 #else
 370 static void *
 371 find_inlist_lock(struct list_head *head,
 372                  const char *name,
 373                  const char *prefix,
 374                  int *error,
 375                  struct semaphore *mutex)
 376 {
 377         void *ret;
 378
 379         ret = find_inlist_lock_noload(head, name, error, mutex);
 380         if (!ret) {
 381                 duprintf("find_inlist: loading `%s%s'.\n", prefix, name);
 382                 request_module("%s%s", prefix, name);
 383                 ret = find_inlist_lock_noload(head, name, error, mutex);
 384         }
 385
 386         return ret;
 387 }
 388 #endif
 389
 390 static inline struct arpt_table *arpt_find_table_lock(const char *name, int *error, struct semaphore *mutex)
 391 {
 392         return find_inlist_lock(&arpt_tables, name, "arptable_", error, mutex);
 393 }
 394
 395 struct arpt_target *arpt_find_target_lock(const char *name, int *error, struct semaphore *mutex)
 396 {
 397         return find_inlist_lock(&arpt_target, name, "arpt_", error, mutex);
 398 }
 399
 400 /* All zeroes == unconditional rule. */
 401 static inline int unconditional(const struct arpt_arp *arp)
 402 {
 403         unsigned int i;
 404
 405         for (i = 0; i < sizeof(*arp)/sizeof(__u32); i++)
 406                 if (((__u32 *)arp)[i])
 407                         return 0;
 408
 409         return 1;
 410 }
 411
 412 /* Figures out from what hook each rule can be called: returns 0 if
 413  * there are loops.  Puts hook bitmask in comefrom.
 414  */
 415 static int mark_source_chains(struct arpt_table_info *newinfo, unsigned int valid_hooks)
 416 {
 417         unsigned int hook;
 418
 419         /* No recursion; use packet counter to save back ptrs (reset
 420          * to 0 as we leave), and comefrom to save source hook bitmask.
 421          */
 422         for (hook = 0; hook < NF_ARP_NUMHOOKS; hook++) {
 423                 unsigned int pos = newinfo->hook_entry[hook];
 424                 struct arpt_entry *e
 425                         = (struct arpt_entry *)(newinfo->entries + pos);
 426
 427                 if (!(valid_hooks & (1 << hook)))
 428                         continue;
 429
 430                 /* Set initial back pointer. */
 431                 e->counters.pcnt = pos;
 432
 433                 for (;;) {
 434                         struct arpt_standard_target *t
 435                                 = (void *)arpt_get_target(e);
 436
 437                         if (e->comefrom & (1 << NF_ARP_NUMHOOKS)) {
 438                                 printk("arptables: loop hook %u pos %u %08X.\n",
 439                                        hook, pos, e->comefrom);
 440                                 return 0;
 441                         }
 442                         e->comefrom
 443                                 |= ((1 << hook) | (1 << NF_ARP_NUMHOOKS));
 444
 445                         /* Unconditional return/END. */
 446                         if (e->target_offset == sizeof(struct arpt_entry)
 447                             && (strcmp(t->target.u.user.name,
 448                                        ARPT_STANDARD_TARGET) == 0)
 449                             && t->verdict < 0
 450                             && unconditional(&e->arp)) {
 451                                 unsigned int oldpos, size;
 452
 453                                 /* Return: backtrack through the last
 454                                  * big jump.
 455                                  */
 456                                 do {
 457                                         e->comefrom ^= (1<<NF_ARP_NUMHOOKS);
 458                                         oldpos = pos;
 459                                         pos = e->counters.pcnt;
 460                                         e->counters.pcnt = 0;
 461
 462                                         /* We're at the start. */
 463                                         if (pos == oldpos)
 464                                                 goto next;
 465
 466                                         e = (struct arpt_entry *)
 467                                                 (newinfo->entries + pos);
 468                                 } while (oldpos == pos + e->next_offset);
 469
 470                                 /* Move along one */
 471                                 size = e->next_offset;
 472                                 e = (struct arpt_entry *)
 473                                         (newinfo->entries + pos + size);
 474                                 e->counters.pcnt = pos;
 475                                 pos += size;
 476                         } else {
 477                                 int newpos = t->verdict;
 478
 479                                 if (strcmp(t->target.u.user.name,
 480                                            ARPT_STANDARD_TARGET) == 0
 481                                     && newpos >= 0) {
 482                                         /* This a jump; chase it. */
 483                                         duprintf("Jump rule %u -> %u\n",
 484                                                  pos, newpos);
 485                                 } else {
 486                                         /* ... this is a fallthru */
 487                                         newpos = pos + e->next_offset;
 488                                 }
 489                                 e = (struct arpt_entry *)
 490                                         (newinfo->entries + newpos);
 491                                 e->counters.pcnt = pos;
 492                                 pos = newpos;
 493                         }
 494                 }
 495                 next:
 496                 duprintf("Finished chain %u\n", hook);
 497         }
 498         return 1;
 499 }
 500
 501 static inline int standard_check(const struct arpt_entry_target *t,
 502                                  unsigned int max_offset)
 503 {
 504         struct arpt_standard_target *targ = (void *)t;
 505
 506         /* Check standard info. */
 507         if (t->u.target_size
 508             != ARPT_ALIGN(sizeof(struct arpt_standard_target))) {
 509                 duprintf("arpt_standard_check: target size %u != %Zu\n",
 510                          t->u.target_size,
 511                          ARPT_ALIGN(sizeof(struct arpt_standard_target)));
 512                 return 0;
 513         }
 514
 515         if (targ->verdict >= 0
 516             && targ->verdict > max_offset - sizeof(struct arpt_entry)) {
 517                 duprintf("arpt_standard_check: bad verdict (%i)\n",
 518                          targ->verdict);
 519                 return 0;
 520         }
 521
 522         if (targ->verdict < -NF_MAX_VERDICT - 1) {
 523                 duprintf("arpt_standard_check: bad negative verdict (%i)\n",
 524                          targ->verdict);
 525                 return 0;
 526         }
 527         return 1;
 528 }
 529
 530 static struct arpt_target arpt_standard_target;
 531
 532 static inline int check_entry(struct arpt_entry *e, const char *name, unsigned int size,
 533                               unsigned int *i)
 534 {
 535         struct arpt_entry_target *t;
 536         struct arpt_target *target;
 537         int ret;
 538
 539         if (!arp_checkentry(&e->arp)) {
 540                 duprintf("arp_tables: arp check failed %p %s.\n", e, name);
 541                 return -EINVAL;
 542         }
 543
 544         t = arpt_get_target(e);
 545         target = arpt_find_target_lock(t->u.user.name, &ret, &arpt_mutex);
 546         if (!target) {
 547                 duprintf("check_entry: `%s' not found\n", t->u.user.name);
 548                 goto out;
 549         }
 550         if (!try_module_get((target->me))) {
 551                 ret = -ENOENT;
 552                 goto out_unlock;
 553         }
 554         t->u.kernel.target = target;
 555         up(&arpt_mutex);
 556
 557         if (t->u.kernel.target == &arpt_standard_target) {
 558                 if (!standard_check(t, size)) {
 559                         ret = -EINVAL;
 560                         goto out;
 561                 }
 562         } else if (t->u.kernel.target->checkentry
 563                    && !t->u.kernel.target->checkentry(name, e, t->data,
 564                                                       t->u.target_size
 565                                                       - sizeof(*t),
 566                                                       e->comefrom)) {
 567                 module_put(t->u.kernel.target->me);
 568                 duprintf("arp_tables: check failed for `%s'.\n",
 569                          t->u.kernel.target->name);
 570                 ret = -EINVAL;
 571                 goto out;
 572         }
 573
 574         (*i)++;
 575         return 0;
 576
 577 out_unlock:
 578         up(&arpt_mutex);
 579 out:
 580         return ret;
 581 }
 582
 583 static inline int check_entry_size_and_hooks(struct arpt_entry *e,
 584                                              struct arpt_table_info *newinfo,
 585                                              unsigned char *base,
 586                                              unsigned char *limit,
 587                                              const unsigned int *hook_entries,
 588                                              const unsigned int *underflows,
 589                                              unsigned int *i)
 590 {
 591         unsigned int h;
 592
 593         if ((unsigned long)e % __alignof__(struct arpt_entry) != 0
 594             || (unsigned char *)e + sizeof(struct arpt_entry) >= limit) {
 595                 duprintf("Bad offset %p\n", e);
 596                 return -EINVAL;
 597         }
 598
 599         if (e->next_offset
 600             < sizeof(struct arpt_entry) + sizeof(struct arpt_entry_target)) {
 601                 duprintf("checking: element %p size %u\n",
 602                          e, e->next_offset);
 603                 return -EINVAL;
 604         }
 605
 606         /* Check hooks & underflows */
 607         for (h = 0; h < NF_ARP_NUMHOOKS; h++) {
 608                 if ((unsigned char *)e - base == hook_entries[h])
 609                         newinfo->hook_entry[h] = hook_entries[h];
 610                 if ((unsigned char *)e - base == underflows[h])
 611                         newinfo->underflow[h] = underflows[h];
 612         }
 613
 614         /* FIXME: underflows must be unconditional, standard verdicts
 615            < 0 (not ARPT_RETURN). --RR */
 616
 617         /* Clear counters and comefrom */
 618         e->counters = ((struct arpt_counters) { 0, 0 });
 619         e->comefrom = 0;
 620
 621         (*i)++;
 622         return 0;
 623 }
 624
 625 static inline int cleanup_entry(struct arpt_entry *e, unsigned int *i)
 626 {
 627         struct arpt_entry_target *t;
 628
 629         if (i && (*i)-- == 0)
 630                 return 1;
 631
 632         t = arpt_get_target(e);
 633         if (t->u.kernel.target->destroy)
 634                 t->u.kernel.target->destroy(t->data,
 635                                             t->u.target_size - sizeof(*t));
 636         module_put(t->u.kernel.target->me);
 637         return 0;
 638 }
 639
 640 /* Checks and translates the user-supplied table segment (held in
 641  * newinfo).
 642  */
 643 static int translate_table(const char *name,
 644                            unsigned int valid_hooks,
 645                            struct arpt_table_info *newinfo,
 646                            unsigned int size,
 647                            unsigned int number,
 648                            const unsigned int *hook_entries,
 649                            const unsigned int *underflows)
 650 {
 651         unsigned int i;
 652         int ret;
 653
 654         newinfo->size = size;
 655         newinfo->number = number;
 656
 657         /* Init all hooks to impossible value. */
 658         for (i = 0; i < NF_ARP_NUMHOOKS; i++) {
 659                 newinfo->hook_entry[i] = 0xFFFFFFFF;
 660                 newinfo->underflow[i] = 0xFFFFFFFF;
 661         }
 662
 663         duprintf("translate_table: size %u\n", newinfo->size);
 664         i = 0;
 665
 666         /* Walk through entries, checking offsets. */
 667         ret = ARPT_ENTRY_ITERATE(newinfo->entries, newinfo->size,
 668                                  check_entry_size_and_hooks,
 669                                  newinfo,
 670                                  newinfo->entries,
 671                                  newinfo->entries + size,
 672                                  hook_entries, underflows, &i);
 673         duprintf("translate_table: ARPT_ENTRY_ITERATE gives %d\n", ret);
 674         if (ret != 0)
 675                 return ret;
 676
 677         if (i != number) {
 678                 duprintf("translate_table: %u not %u entries\n",
 679                          i, number);
 680                 return -EINVAL;
 681         }
 682
 683         /* Check hooks all assigned */
 684         for (i = 0; i < NF_ARP_NUMHOOKS; i++) {
 685                 /* Only hooks which are valid */
 686                 if (!(valid_hooks & (1 << i)))
 687                         continue;
 688                 if (newinfo->hook_entry[i] == 0xFFFFFFFF) {
 689                         duprintf("Invalid hook entry %u %u\n",
 690                                  i, hook_entries[i]);
 691                         return -EINVAL;
 692                 }
 693                 if (newinfo->underflow[i] == 0xFFFFFFFF) {
 694                         duprintf("Invalid underflow %u %u\n",
 695                                  i, underflows[i]);
 696                         return -EINVAL;
 697                 }
 698         }
 699
 700         if (!mark_source_chains(newinfo, valid_hooks)) {
 701                 duprintf("Looping hook\n");
 702                 return -ELOOP;
 703         }
 704
 705         /* Finally, each sanity check must pass */
 706         i = 0;
 707         ret = ARPT_ENTRY_ITERATE(newinfo->entries, newinfo->size,
 708                                  check_entry, name, size, &i);
 709
 710         if (ret != 0) {
 711                 ARPT_ENTRY_ITERATE(newinfo->entries, newinfo->size,
 712                                    cleanup_entry, &i);
 713                 return ret;
 714         }
 715
 716         /* And one copy for every other CPU */
 717         for (i = 1; i < NR_CPUS; i++) {
 718                 memcpy(newinfo->entries + SMP_ALIGN(newinfo->size)*i,
 719                        newinfo->entries,
 720                        SMP_ALIGN(newinfo->size));
 721         }
 722
 723         return ret;
 724 }
 725
 726 static struct arpt_table_info *replace_table(struct arpt_table *table,
 727                                              unsigned int num_counters,
 728                                              struct arpt_table_info *newinfo,
 729                                              int *error)
 730 {
 731         struct arpt_table_info *oldinfo;
 732
 733         /* Do the substitution. */
 734         write_lock_bh(&table->lock);
 735         /* Check inside lock: is the old number correct? */
 736         if (num_counters != table->private->number) {
 737                 duprintf("num_counters != table->private->number (%u/%u)\n",
 738                          num_counters, table->private->number);
 739                 write_unlock_bh(&table->lock);
 740                 *error = -EAGAIN;
 741                 return NULL;
 742         }
 743         oldinfo = table->private;
 744         table->private = newinfo;
 745         newinfo->initial_entries = oldinfo->initial_entries;
 746         write_unlock_bh(&table->lock);
 747
 748         return oldinfo;
 749 }
 750
 751 /* Gets counters. */
 752 static inline int add_entry_to_counter(const struct arpt_entry *e,
 753                                        struct arpt_counters total[],
 754                                        unsigned int *i)
 755 {
 756         ADD_COUNTER(total[*i], e->counters.bcnt, e->counters.pcnt);
 757
 758         (*i)++;
 759         return 0;
 760 }
 761
 762 static void get_counters(const struct arpt_table_info *t,
 763                          struct arpt_counters counters[])
 764 {
 765         unsigned int cpu;
 766         unsigned int i;
 767
 768         for (cpu = 0; cpu < NR_CPUS; cpu++) {
 769                 i = 0;
 770                 ARPT_ENTRY_ITERATE(t->entries + TABLE_OFFSET(t, cpu),
 771                                    t->size,
 772                                    add_entry_to_counter,
 773                                    counters,
 774                                    &i);
 775         }
 776 }
 777
 778 static int copy_entries_to_user(unsigned int total_size,
 779                                 struct arpt_table *table,
 780                                 void __user *userptr)
 781 {
 782         unsigned int off, num, countersize;
 783         struct arpt_entry *e;
 784         struct arpt_counters *counters;
 785         int ret = 0;
 786
 787         /* We need atomic snapshot of counters: rest doesn't change
 788          * (other than comefrom, which userspace doesn't care
 789          * about).
 790          */
 791         countersize = sizeof(struct arpt_counters) * table->private->number;
 792         counters = vmalloc(countersize);
 793
 794         if (counters == NULL)
 795                 return -ENOMEM;
 796
 797         /* First, sum counters... */
 798         memset(counters, 0, countersize);
 799         write_lock_bh(&table->lock);
 800         get_counters(table->private, counters);
 801         write_unlock_bh(&table->lock);
 802
 803         /* ... then copy entire thing from CPU 0... */
 804         if (copy_to_user(userptr, table->private->entries, total_size) != 0) {
 805                 ret = -EFAULT;
 806                 goto free_counters;
 807         }
 808
 809         /* FIXME: use iterator macros --RR */
 810         /* ... then go back and fix counters and names */
 811         for (off = 0, num = 0; off < total_size; off += e->next_offset, num++){
 812                 struct arpt_entry_target *t;
 813
 814                 e = (struct arpt_entry *)(table->private->entries + off);
 815                 if (copy_to_user(userptr + off
 816                                  + offsetof(struct arpt_entry, counters),
 817                                  &counters[num],
 818                                  sizeof(counters[num])) != 0) {
 819                         ret = -EFAULT;
 820                         goto free_counters;
 821                 }
 822
 823                 t = arpt_get_target(e);
 824                 if (copy_to_user(userptr + off + e->target_offset
 825                                  + offsetof(struct arpt_entry_target,
 826                                             u.user.name),
 827                                  t->u.kernel.target->name,
 828                                  strlen(t->u.kernel.target->name)+1) != 0) {
 829                         ret = -EFAULT;
 830                         goto free_counters;
 831                 }
 832         }
 833
 834  free_counters:
 835         vfree(counters);
 836         return ret;
 837 }
 838
 839 static int get_entries(const struct arpt_get_entries *entries,
 840                        struct arpt_get_entries __user *uptr)
 841 {
 842         int ret;
 843         struct arpt_table *t;
 844
 845         t = arpt_find_table_lock(entries->name, &ret, &arpt_mutex);
 846         if (t) {
 847                 duprintf("t->private->number = %u\n",
 848                          t->private->number);
 849                 if (entries->size == t->private->size)
 850                         ret = copy_entries_to_user(t->private->size,
 851                                                    t, uptr->entrytable);
 852                 else {
 853                         duprintf("get_entries: I've got %u not %u!\n",
 854                                  t->private->size,
 855                                  entries->size);
 856                         ret = -EINVAL;
 857                 }
 858                 up(&arpt_mutex);
 859         } else
 860                 duprintf("get_entries: Can't find %s!\n",
 861                          entries->name);
 862
 863         return ret;
 864 }
 865
 866 static int do_replace(void __user *user, unsigned int len)
 867 {
 868         int ret;
 869         struct arpt_replace tmp;
 870         struct arpt_table *t;
 871         struct arpt_table_info *newinfo, *oldinfo;
 872         struct arpt_counters *counters;
 873
 874         if (copy_from_user(&tmp, user, sizeof(tmp)) != 0)
 875                 return -EFAULT;
 876
 877         /* Hack: Causes ipchains to give correct error msg --RR */
 878         if (len != sizeof(tmp) + tmp.size)
 879                 return -ENOPROTOOPT;
 880
 881         /* Pedantry: prevent them from hitting BUG() in vmalloc.c --RR */
 882         if ((SMP_ALIGN(tmp.size) >> PAGE_SHIFT) + 2 > num_physpages)
 883                 return -ENOMEM;
 884
 885         newinfo = vmalloc(sizeof(struct arpt_table_info)
 886                           + SMP_ALIGN(tmp.size) * NR_CPUS);
 887         if (!newinfo)
 888                 return -ENOMEM;
 889
 890         if (copy_from_user(newinfo->entries, user + sizeof(tmp),
 891                            tmp.size) != 0) {
 892                 ret = -EFAULT;
 893                 goto free_newinfo;
 894         }
 895
 896         counters = vmalloc(tmp.num_counters * sizeof(struct arpt_counters));
 897         if (!counters) {
 898                 ret = -ENOMEM;
 899                 goto free_newinfo;
 900         }
 901         memset(counters, 0, tmp.num_counters * sizeof(struct arpt_counters));
 902
 903         ret = translate_table(tmp.name, tmp.valid_hooks,
 904                               newinfo, tmp.size, tmp.num_entries,
 905                               tmp.hook_entry, tmp.underflow);
 906         if (ret != 0)
 907                 goto free_newinfo_counters;
 908
 909         duprintf("arp_tables: Translated table\n");
 910
 911         t = arpt_find_table_lock(tmp.name, &ret, &arpt_mutex);
 912         if (!t)
 913                 goto free_newinfo_counters_untrans;
 914
 915         /* You lied! */
 916         if (tmp.valid_hooks != t->valid_hooks) {
 917                 duprintf("Valid hook crap: %08X vs %08X\n",
 918                          tmp.valid_hooks, t->valid_hooks);
 919                 ret = -EINVAL;
 920                 goto free_newinfo_counters_untrans_unlock;
 921         }
 922
 923         /* Get a reference in advance, we're not allowed fail later */
 924         if (!try_module_get(t->me)) {
 925                 ret = -EBUSY;
 926                 goto free_newinfo_counters_untrans_unlock;
 927         }
 928
 929         oldinfo = replace_table(t, tmp.num_counters, newinfo, &ret);
 930         if (!oldinfo)
 931                 goto put_module;
 932
 933         /* Update module usage count based on number of rules */
 934         duprintf("do_replace: oldnum=%u, initnum=%u, newnum=%u\n",
 935                 oldinfo->number, oldinfo->initial_entries, newinfo->number);
 936         if ((oldinfo->number > oldinfo->initial_entries) ||
 937             (newinfo->number <= oldinfo->initial_entries))
 938                 module_put(t->me);
 939         if ((oldinfo->number > oldinfo->initial_entries) &&
 940             (newinfo->number <= oldinfo->initial_entries))
 941                 module_put(t->me);
 942
 943         /* Get the old counters. */
 944         get_counters(oldinfo, counters);
 945         /* Decrease module usage counts and free resource */
 946         ARPT_ENTRY_ITERATE(oldinfo->entries, oldinfo->size, cleanup_entry,NULL);
 947         vfree(oldinfo);
 948         /* Silent error: too late now. */
 949         copy_to_user(tmp.counters, counters,
 950                      sizeof(struct arpt_counters) * tmp.num_counters);
 951         vfree(counters);
 952         up(&arpt_mutex);
 953         return 0;
 954
 955  put_module:
 956         module_put(t->me);
 957  free_newinfo_counters_untrans_unlock:
 958         up(&arpt_mutex);
 959  free_newinfo_counters_untrans:
 960         ARPT_ENTRY_ITERATE(newinfo->entries, newinfo->size, cleanup_entry, NULL);
 961  free_newinfo_counters:
 962         vfree(counters);
 963  free_newinfo:
 964         vfree(newinfo);
 965         return ret;
 966 }
 967
 968 /* We're lazy, and add to the first CPU; overflow works its fey magic
 969  * and everything is OK.
 970  */
 971 static inline int add_counter_to_entry(struct arpt_entry *e,
 972                                        const struct arpt_counters addme[],
 973                                        unsigned int *i)
 974 {
 975
 976         ADD_COUNTER(e->counters, addme[*i].bcnt, addme[*i].pcnt);
 977
 978         (*i)++;
 979         return 0;
 980 }
 981
 982 static int do_add_counters(void __user *user, unsigned int len)
 983 {
 984         unsigned int i;
 985         struct arpt_counters_info tmp, *paddc;
 986         struct arpt_table *t;
 987         int ret;
 988
 989         if (copy_from_user(&tmp, user, sizeof(tmp)) != 0)
 990                 return -EFAULT;
 991
 992         if (len != sizeof(tmp) + tmp.num_counters*sizeof(struct arpt_counters))
 993                 return -EINVAL;
 994
 995         paddc = vmalloc(len);
 996         if (!paddc)
 997                 return -ENOMEM;
 998
 999         if (copy_from_user(paddc, user, len) != 0) {
1000                 ret = -EFAULT;
1001                 goto free;
1002         }
1003
1004         t = arpt_find_table_lock(tmp.name, &ret, &arpt_mutex);
1005         if (!t)
1006                 goto free;
1007
1008         write_lock_bh(&t->lock);
1009         if (t->private->number != paddc->num_counters) {
1010                 ret = -EINVAL;
1011                 goto unlock_up_free;
1012         }
1013
1014         i = 0;
1015         ARPT_ENTRY_ITERATE(t->private->entries,
1016                            t->private->size,
1017                            add_counter_to_entry,
1018                            paddc->counters,
1019                            &i);
1020  unlock_up_free:
1021         write_unlock_bh(&t->lock);
1022         up(&arpt_mutex);
1023  free:
1024         vfree(paddc);
1025
1026         return ret;
1027 }
1028
1029 static int do_arpt_set_ctl(struct sock *sk, int cmd, void __user *user, unsigned int len)
1030 {
1031         int ret;
1032
1033         if (!capable(CAP_NET_ADMIN))
1034                 return -EPERM;
1035
1036         switch (cmd) {
1037         case ARPT_SO_SET_REPLACE:
1038                 ret = do_replace(user, len);
1039                 break;
1040
1041         case ARPT_SO_SET_ADD_COUNTERS:
1042                 ret = do_add_counters(user, len);
1043                 break;
1044
1045         default:
1046                 duprintf("do_arpt_set_ctl:  unknown request %i\n", cmd);
1047                 ret = -EINVAL;
1048         }
1049
1050         return ret;
1051 }
1052
1053 static int do_arpt_get_ctl(struct sock *sk, int cmd, void __user *user, int *len)
1054 {
1055         int ret;
1056
1057         if (!capable(CAP_NET_ADMIN))
1058                 return -EPERM;
1059
1060         switch (cmd) {
1061         case ARPT_SO_GET_INFO: {
1062                 char name[ARPT_TABLE_MAXNAMELEN];
1063                 struct arpt_table *t;
1064
1065                 if (*len != sizeof(struct arpt_getinfo)) {
1066                         duprintf("length %u != %Zu\n", *len,
1067                                  sizeof(struct arpt_getinfo));
1068                         ret = -EINVAL;
1069                         break;
1070                 }
1071
1072                 if (copy_from_user(name, user, sizeof(name)) != 0) {
1073                         ret = -EFAULT;
1074                         break;
1075                 }
1076                 name[ARPT_TABLE_MAXNAMELEN-1] = '\0';
1077                 t = arpt_find_table_lock(name, &ret, &arpt_mutex);
1078                 if (t) {
1079                         struct arpt_getinfo info;
1080
1081                         info.valid_hooks = t->valid_hooks;
1082                         memcpy(info.hook_entry, t->private->hook_entry,
1083                                sizeof(info.hook_entry));
1084                         memcpy(info.underflow, t->private->underflow,
1085                                sizeof(info.underflow));
1086                         info.num_entries = t->private->number;
1087                         info.size = t->private->size;
1088                         strcpy(info.name, name);
1089
1090                         if (copy_to_user(user, &info, *len) != 0)
1091                                 ret = -EFAULT;
1092                         else
1093                                 ret = 0;
1094
1095                         up(&arpt_mutex);
1096                 }
1097         }
1098         break;
1099
1100         case ARPT_SO_GET_ENTRIES: {
1101                 struct arpt_get_entries get;
1102
1103                 if (*len < sizeof(get)) {
1104                         duprintf("get_entries: %u < %Zu\n", *len, sizeof(get));
1105                         ret = -EINVAL;
1106                 } else if (copy_from_user(&get, user, sizeof(get)) != 0) {
1107                         ret = -EFAULT;
1108                 } else if (*len != sizeof(struct arpt_get_entries) + get.size) {
1109                         duprintf("get_entries: %u != %Zu\n", *len,
1110                                  sizeof(struct arpt_get_entries) + get.size);
1111                         ret = -EINVAL;
1112                 } else
1113                         ret = get_entries(&get, user);
1114                 break;
1115         }
1116
1117         default:
1118                 duprintf("do_arpt_get_ctl: unknown request %i\n", cmd);
1119                 ret = -EINVAL;
1120         }
1121
1122         return ret;
1123 }
1124
1125 /* Registration hooks for targets. */
1126 int arpt_register_target(struct arpt_target *target)
1127 {
1128         int ret;
1129
1130         ret = down_interruptible(&arpt_mutex);
1131         if (ret != 0)
1132                 return ret;
1133
1134         if (!list_named_insert(&arpt_target, target)) {
1135                 duprintf("arpt_register_target: `%s' already in list!\n",
1136                          target->name);
1137                 ret = -EINVAL;
1138         }
1139         up(&arpt_mutex);
1140         return ret;
1141 }
1142
1143 void arpt_unregister_target(struct arpt_target *target)
1144 {
1145         down(&arpt_mutex);
1146         LIST_DELETE(&arpt_target, target);
1147         up(&arpt_mutex);
1148 }
1149
1150 int arpt_register_table(struct arpt_table *table)
1151 {
1152         int ret;
1153         struct arpt_table_info *newinfo;
1154         static struct arpt_table_info bootstrap
1155                 = { 0, 0, 0, { 0 }, { 0 }, { } };
1156
1157         newinfo = vmalloc(sizeof(struct arpt_table_info)
1158                           + SMP_ALIGN(table->table->size) * NR_CPUS);
1159         if (!newinfo) {
1160                 ret = -ENOMEM;
1161                 return ret;
1162         }
1163         memcpy(newinfo->entries, table->table->entries, table->table->size);
1164
1165         ret = translate_table(table->name, table->valid_hooks,
1166                               newinfo, table->table->size,
1167                               table->table->num_entries,
1168                               table->table->hook_entry,
1169                               table->table->underflow);
1170         duprintf("arpt_register_table: translate table gives %d\n", ret);
1171         if (ret != 0) {
1172                 vfree(newinfo);
1173                 return ret;
1174         }
1175
1176         ret = down_interruptible(&arpt_mutex);
1177         if (ret != 0) {
1178                 vfree(newinfo);
1179                 return ret;
1180         }
1181
1182         /* Don't autoload: we'd eat our tail... */
1183         if (list_named_find(&arpt_tables, table->name)) {
1184                 ret = -EEXIST;
1185                 goto free_unlock;
1186         }
1187
1188         /* Simplifies replace_table code. */
1189         table->private = &bootstrap;
1190         if (!replace_table(table, 0, newinfo, &ret))
1191                 goto free_unlock;
1192
1193         duprintf("table->private->number = %u\n",
1194                  table->private->number);
1195
1196         /* save number of initial entries */
1197         table->private->initial_entries = table->private->number;
1198
1199         table->lock = RW_LOCK_UNLOCKED;
1200         list_prepend(&arpt_tables, table);
1201
1202  unlock:
1203         up(&arpt_mutex);
1204         return ret;
1205
1206  free_unlock:
1207         vfree(newinfo);
1208         goto unlock;
1209 }
1210
1211 void arpt_unregister_table(struct arpt_table *table)
1212 {
1213         down(&arpt_mutex);
1214         LIST_DELETE(&arpt_tables, table);
1215         up(&arpt_mutex);
1216
1217         /* Decrease module usage counts and free resources */
1218         ARPT_ENTRY_ITERATE(table->private->entries, table->private->size,
1219                            cleanup_entry, NULL);
1220         vfree(table->private);
1221 }
1222
1223 /* The built-in targets: standard (NULL) and error. */
1224 static struct arpt_target arpt_standard_target = {
1225         .name           = ARPT_STANDARD_TARGET,
1226 };
1227
1228 static struct arpt_target arpt_error_target = {
1229         .name           = ARPT_ERROR_TARGET,
1230         .target         = arpt_error,
1231 };
1232
1233 static struct nf_sockopt_ops arpt_sockopts = {
1234         .pf             = PF_INET,
1235         .set_optmin     = ARPT_BASE_CTL,
1236         .set_optmax     = ARPT_SO_SET_MAX+1,
1237         .set            = do_arpt_set_ctl,
1238         .get_optmin     = ARPT_BASE_CTL,
1239         .get_optmax     = ARPT_SO_GET_MAX+1,
1240         .get            = do_arpt_get_ctl,
1241 };
1242
1243 #ifdef CONFIG_PROC_FS
1244 static inline int print_name(const struct arpt_table *t,
1245                              off_t start_offset, char *buffer, int length,
1246                              off_t *pos, unsigned int *count)
1247 {
1248         if ((*count)++ >= start_offset) {
1249                 unsigned int namelen;
1250
1251                 namelen = sprintf(buffer + *pos, "%s\n", t->name);
1252                 if (*pos + namelen > length) {
1253                         /* Stop iterating */
1254                         return 1;
1255                 }
1256                 *pos += namelen;
1257         }
1258         return 0;
1259 }
1260
1261 static int arpt_get_tables(char *buffer, char **start, off_t offset, int length)
1262 {
1263         off_t pos = 0;
1264         unsigned int count = 0;
1265
1266         if (down_interruptible(&arpt_mutex) != 0)
1267                 return 0;
1268
1269         LIST_FIND(&arpt_tables, print_name, struct arpt_table *,
1270                   offset, buffer, length, &pos, &count);
1271
1272         up(&arpt_mutex);
1273
1274         /* `start' hack - see fs/proc/generic.c line ~105 */
1275         *start=(char *)((unsigned long)count-offset);
1276         return pos;
1277 }
1278 #endif /*CONFIG_PROC_FS*/
1279
1280 static int __init init(void)
1281 {
1282         int ret;
1283
1284         /* Noone else will be downing sem now, so we won't sleep */
1285         down(&arpt_mutex);
1286         list_append(&arpt_target, &arpt_standard_target);
1287         list_append(&arpt_target, &arpt_error_target);
1288         up(&arpt_mutex);
1289
1290         /* Register setsockopt */
1291         ret = nf_register_sockopt(&arpt_sockopts);
1292         if (ret < 0) {
1293                 duprintf("Unable to register sockopts.\n");
1294                 return ret;
1295         }
1296
1297 #ifdef CONFIG_PROC_FS
1298         {
1299                 struct proc_dir_entry *proc;
1300
1301                 proc = proc_net_create("arp_tables_names", 0, arpt_get_tables);
1302                 if (!proc) {
1303                         nf_unregister_sockopt(&arpt_sockopts);
1304                         return -ENOMEM;
1305                 }
1306                 proc->owner = THIS_MODULE;
1307         }
1308 #endif
1309
1310         printk("arp_tables: (C) 2002 David S. Miller\n");
1311         return 0;
1312 }
1313
1314 static void __exit fini(void)
1315 {
1316         nf_unregister_sockopt(&arpt_sockopts);
1317 #ifdef CONFIG_PROC_FS
1318         proc_net_remove("arp_tables_names");
1319 #endif
1320 }
1321
1322 EXPORT_SYMBOL(arpt_register_table);
1323 EXPORT_SYMBOL(arpt_unregister_table);
1324 EXPORT_SYMBOL(arpt_do_table);
1325 EXPORT_SYMBOL(arpt_find_target_lock);
1326 EXPORT_SYMBOL(arpt_register_target);
1327 EXPORT_SYMBOL(arpt_unregister_target);
1328
1329 module_init(init);
1330 module_exit(fini);