1 /* 2 * Copyright (c) 2006 Patrick McHardy <kaber@trash.net> 3 * Copyright © CC Computer Consultants GmbH, 2007 - 2008 4 * 5 * This program is free software; you can redistribute it and/or modify 6 * it under the terms of the GNU General Public License version 2 as 7 * published by the Free Software Foundation. 8 * 9 * This is a replacement of the old ipt_recent module, which carried the 10 * following copyright notice: 11 * 12 * Author: Stephen Frost <sfrost@snowman.net> 13 * Copyright 2002-2003, Stephen Frost, 2.5.x port by laforge@netfilter.org 14 */ 15 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt 16 #include <linux/init.h> 17 #include <linux/ip.h> 18 #include <linux/ipv6.h> 19 #include <linux/module.h> 20 #include <linux/moduleparam.h> 21 #include <linux/proc_fs.h> 22 #include <linux/seq_file.h> 23 #include <linux/string.h> 24 #include <linux/ctype.h> 25 #include <linux/list.h> 26 #include <linux/random.h> 27 #include <linux/jhash.h> 28 #include <linux/bitops.h> 29 #include <linux/skbuff.h> 30 #include <linux/inet.h> 31 #include <linux/slab.h> 32 #include <linux/vmalloc.h> 33 #include <net/net_namespace.h> 34 #include <net/netns/generic.h> 35 36 #include <linux/netfilter/x_tables.h> 37 #include <linux/netfilter/xt_recent.h> 38 39 MODULE_AUTHOR("Patrick McHardy <kaber@trash.net>"); 40 MODULE_AUTHOR("Jan Engelhardt <jengelh@medozas.de>"); 41 MODULE_DESCRIPTION("Xtables: \"recently-seen\" host matching"); 42 MODULE_LICENSE("GPL"); 43 MODULE_ALIAS("ipt_recent"); 44 MODULE_ALIAS("ip6t_recent"); 45 46 static unsigned int ip_list_tot = 100; 47 static unsigned int ip_pkt_list_tot = 20; 48 static unsigned int ip_list_hash_size = 0; 49 static unsigned int ip_list_perms = 0644; 50 static unsigned int ip_list_uid = 0; 51 static unsigned int ip_list_gid = 0; 52 module_param(ip_list_tot, uint, 0400); 53 module_param(ip_pkt_list_tot, uint, 0400); 54 module_param(ip_list_hash_size, uint, 0400); 55 module_param(ip_list_perms, uint, 0400); 56 module_param(ip_list_uid, uint, S_IRUGO | S_IWUSR); 57 module_param(ip_list_gid, uint, S_IRUGO | S_IWUSR); 58 MODULE_PARM_DESC(ip_list_tot, "number of IPs to remember per list"); 59 MODULE_PARM_DESC(ip_pkt_list_tot, "number of packets per IP address to remember (max. 255)"); 60 MODULE_PARM_DESC(ip_list_hash_size, "size of hash table used to look up IPs"); 61 MODULE_PARM_DESC(ip_list_perms, "permissions on /proc/net/xt_recent/* files"); 62 MODULE_PARM_DESC(ip_list_uid, "default owner of /proc/net/xt_recent/* files"); 63 MODULE_PARM_DESC(ip_list_gid, "default owning group of /proc/net/xt_recent/* files"); 64 65 struct recent_entry { 66 struct list_head list; 67 struct list_head lru_list; 68 union nf_inet_addr addr; 69 u_int16_t family; 70 u_int8_t ttl; 71 u_int8_t index; 72 u_int16_t nstamps; 73 unsigned long stamps[0]; 74 }; 75 76 struct recent_table { 77 struct list_head list; 78 char name[XT_RECENT_NAME_LEN]; 79 union nf_inet_addr mask; 80 unsigned int refcnt; 81 unsigned int entries; 82 struct list_head lru_list; 83 struct list_head iphash[0]; 84 }; 85 86 struct recent_net { 87 struct list_head tables; 88 #ifdef CONFIG_PROC_FS 89 struct proc_dir_entry *xt_recent; 90 #endif 91 }; 92 93 static int recent_net_id; 94 static inline struct recent_net *recent_pernet(struct net *net) 95 { 96 return net_generic(net, recent_net_id); 97 } 98 99 static DEFINE_SPINLOCK(recent_lock); 100 static DEFINE_MUTEX(recent_mutex); 101 102 #ifdef CONFIG_PROC_FS 103 static const struct file_operations recent_old_fops, recent_mt_fops; 104 #endif 105 106 static u_int32_t hash_rnd __read_mostly; 107 static bool hash_rnd_inited __read_mostly; 108 109 static inline unsigned int recent_entry_hash4(const union nf_inet_addr *addr) 110 { 111 return jhash_1word((__force u32)addr->ip, hash_rnd) & 112 (ip_list_hash_size - 1); 113 } 114 115 static inline unsigned int recent_entry_hash6(const union nf_inet_addr *addr) 116 { 117 return jhash2((u32 *)addr->ip6, ARRAY_SIZE(addr->ip6), hash_rnd) & 118 (ip_list_hash_size - 1); 119 } 120 121 static struct recent_entry * 122 recent_entry_lookup(const struct recent_table *table, 123 const union nf_inet_addr *addrp, u_int16_t family, 124 u_int8_t ttl) 125 { 126 struct recent_entry *e; 127 unsigned int h; 128 129 if (family == NFPROTO_IPV4) 130 h = recent_entry_hash4(addrp); 131 else 132 h = recent_entry_hash6(addrp); 133 134 list_for_each_entry(e, &table->iphash[h], list) 135 if (e->family == family && 136 memcmp(&e->addr, addrp, sizeof(e->addr)) == 0 && 137 (ttl == e->ttl || ttl == 0 || e->ttl == 0)) 138 return e; 139 return NULL; 140 } 141 142 static void recent_entry_remove(struct recent_table *t, struct recent_entry *e) 143 { 144 list_del(&e->list); 145 list_del(&e->lru_list); 146 kfree(e); 147 t->entries--; 148 } 149 150 /* 151 * Drop entries with timestamps older then 'time'. 152 */ 153 static void recent_entry_reap(struct recent_table *t, unsigned long time) 154 { 155 struct recent_entry *e; 156 157 /* 158 * The head of the LRU list is always the oldest entry. 159 */ 160 e = list_entry(t->lru_list.next, struct recent_entry, lru_list); 161 162 /* 163 * The last time stamp is the most recent. 164 */ 165 if (time_after(time, e->stamps[e->index-1])) 166 recent_entry_remove(t, e); 167 } 168 169 static struct recent_entry * 170 recent_entry_init(struct recent_table *t, const union nf_inet_addr *addr, 171 u_int16_t family, u_int8_t ttl) 172 { 173 struct recent_entry *e; 174 175 if (t->entries >= ip_list_tot) { 176 e = list_entry(t->lru_list.next, struct recent_entry, lru_list); 177 recent_entry_remove(t, e); 178 } 179 e = kmalloc(sizeof(*e) + sizeof(e->stamps[0]) * ip_pkt_list_tot, 180 GFP_ATOMIC); 181 if (e == NULL) 182 return NULL; 183 memcpy(&e->addr, addr, sizeof(e->addr)); 184 e->ttl = ttl; 185 e->stamps[0] = jiffies; 186 e->nstamps = 1; 187 e->index = 1; 188 e->family = family; 189 if (family == NFPROTO_IPV4) 190 list_add_tail(&e->list, &t->iphash[recent_entry_hash4(addr)]); 191 else 192 list_add_tail(&e->list, &t->iphash[recent_entry_hash6(addr)]); 193 list_add_tail(&e->lru_list, &t->lru_list); 194 t->entries++; 195 return e; 196 } 197 198 static void recent_entry_update(struct recent_table *t, struct recent_entry *e) 199 { 200 e->index %= ip_pkt_list_tot; 201 e->stamps[e->index++] = jiffies; 202 if (e->index > e->nstamps) 203 e->nstamps = e->index; 204 list_move_tail(&e->lru_list, &t->lru_list); 205 } 206 207 static struct recent_table *recent_table_lookup(struct recent_net *recent_net, 208 const char *name) 209 { 210 struct recent_table *t; 211 212 list_for_each_entry(t, &recent_net->tables, list) 213 if (!strcmp(t->name, name)) 214 return t; 215 return NULL; 216 } 217 218 static void recent_table_flush(struct recent_table *t) 219 { 220 struct recent_entry *e, *next; 221 unsigned int i; 222 223 for (i = 0; i < ip_list_hash_size; i++) 224 list_for_each_entry_safe(e, next, &t->iphash[i], list) 225 recent_entry_remove(t, e); 226 } 227 228 static bool 229 recent_mt(const struct sk_buff *skb, struct xt_action_param *par) 230 { 231 struct net *net = dev_net(par->in ? par->in : par->out); 232 struct recent_net *recent_net = recent_pernet(net); 233 const struct xt_recent_mtinfo_v1 *info = par->matchinfo; 234 struct recent_table *t; 235 struct recent_entry *e; 236 union nf_inet_addr addr = {}, addr_mask; 237 u_int8_t ttl; 238 bool ret = info->invert; 239 240 if (par->family == NFPROTO_IPV4) { 241 const struct iphdr *iph = ip_hdr(skb); 242 243 if (info->side == XT_RECENT_DEST) 244 addr.ip = iph->daddr; 245 else 246 addr.ip = iph->saddr; 247 248 ttl = iph->ttl; 249 } else { 250 const struct ipv6hdr *iph = ipv6_hdr(skb); 251 252 if (info->side == XT_RECENT_DEST) 253 memcpy(&addr.in6, &iph->daddr, sizeof(addr.in6)); 254 else 255 memcpy(&addr.in6, &iph->saddr, sizeof(addr.in6)); 256 257 ttl = iph->hop_limit; 258 } 259 260 /* use TTL as seen before forwarding */ 261 if (par->out != NULL && skb->sk == NULL) 262 ttl++; 263 264 spin_lock_bh(&recent_lock); 265 t = recent_table_lookup(recent_net, info->name); 266 267 nf_inet_addr_mask(&addr, &addr_mask, &t->mask); 268 269 e = recent_entry_lookup(t, &addr_mask, par->family, 270 (info->check_set & XT_RECENT_TTL) ? ttl : 0); 271 if (e == NULL) { 272 if (!(info->check_set & XT_RECENT_SET)) 273 goto out; 274 e = recent_entry_init(t, &addr_mask, par->family, ttl); 275 if (e == NULL) 276 par->hotdrop = true; 277 ret = !ret; 278 goto out; 279 } 280 281 if (info->check_set & XT_RECENT_SET) 282 ret = !ret; 283 else if (info->check_set & XT_RECENT_REMOVE) { 284 recent_entry_remove(t, e); 285 ret = !ret; 286 } else if (info->check_set & (XT_RECENT_CHECK | XT_RECENT_UPDATE)) { 287 unsigned long time = jiffies - info->seconds * HZ; 288 unsigned int i, hits = 0; 289 290 for (i = 0; i < e->nstamps; i++) { 291 if (info->seconds && time_after(time, e->stamps[i])) 292 continue; 293 if (!info->hit_count || ++hits >= info->hit_count) { 294 ret = !ret; 295 break; 296 } 297 } 298 299 /* info->seconds must be non-zero */ 300 if (info->check_set & XT_RECENT_REAP) 301 recent_entry_reap(t, time); 302 } 303 304 if (info->check_set & XT_RECENT_SET || 305 (info->check_set & XT_RECENT_UPDATE && ret)) { 306 recent_entry_update(t, e); 307 e->ttl = ttl; 308 } 309 out: 310 spin_unlock_bh(&recent_lock); 311 return ret; 312 } 313 314 static void recent_table_free(void *addr) 315 { 316 if (is_vmalloc_addr(addr)) 317 vfree(addr); 318 else 319 kfree(addr); 320 } 321 322 static int recent_mt_check(const struct xt_mtchk_param *par, 323 const struct xt_recent_mtinfo_v1 *info) 324 { 325 struct recent_net *recent_net = recent_pernet(par->net); 326 struct recent_table *t; 327 #ifdef CONFIG_PROC_FS 328 struct proc_dir_entry *pde; 329 kuid_t uid; 330 kgid_t gid; 331 #endif 332 unsigned int i; 333 int ret = -EINVAL; 334 size_t sz; 335 336 if (unlikely(!hash_rnd_inited)) { 337 get_random_bytes(&hash_rnd, sizeof(hash_rnd)); 338 hash_rnd_inited = true; 339 } 340 if (info->check_set & ~XT_RECENT_VALID_FLAGS) { 341 pr_info("Unsupported user space flags (%08x)\n", 342 info->check_set); 343 return -EINVAL; 344 } 345 if (hweight8(info->check_set & 346 (XT_RECENT_SET | XT_RECENT_REMOVE | 347 XT_RECENT_CHECK | XT_RECENT_UPDATE)) != 1) 348 return -EINVAL; 349 if ((info->check_set & (XT_RECENT_SET | XT_RECENT_REMOVE)) && 350 (info->seconds || info->hit_count || 351 (info->check_set & XT_RECENT_MODIFIERS))) 352 return -EINVAL; 353 if ((info->check_set & XT_RECENT_REAP) && !info->seconds) 354 return -EINVAL; 355 if (info->hit_count > ip_pkt_list_tot) { 356 pr_info("hitcount (%u) is larger than " 357 "packets to be remembered (%u)\n", 358 info->hit_count, ip_pkt_list_tot); 359 return -EINVAL; 360 } 361 if (info->name[0] == '\0' || 362 strnlen(info->name, XT_RECENT_NAME_LEN) == XT_RECENT_NAME_LEN) 363 return -EINVAL; 364 365 mutex_lock(&recent_mutex); 366 t = recent_table_lookup(recent_net, info->name); 367 if (t != NULL) { 368 t->refcnt++; 369 ret = 0; 370 goto out; 371 } 372 373 sz = sizeof(*t) + sizeof(t->iphash[0]) * ip_list_hash_size; 374 if (sz <= PAGE_SIZE) 375 t = kzalloc(sz, GFP_KERNEL); 376 else 377 t = vzalloc(sz); 378 if (t == NULL) { 379 ret = -ENOMEM; 380 goto out; 381 } 382 t->refcnt = 1; 383 384 memcpy(&t->mask, &info->mask, sizeof(t->mask)); 385 strcpy(t->name, info->name); 386 INIT_LIST_HEAD(&t->lru_list); 387 for (i = 0; i < ip_list_hash_size; i++) 388 INIT_LIST_HEAD(&t->iphash[i]); 389 #ifdef CONFIG_PROC_FS 390 uid = make_kuid(&init_user_ns, ip_list_uid); 391 gid = make_kgid(&init_user_ns, ip_list_gid); 392 if (!uid_valid(uid) || !gid_valid(gid)) { 393 recent_table_free(t); 394 ret = -EINVAL; 395 goto out; 396 } 397 pde = proc_create_data(t->name, ip_list_perms, recent_net->xt_recent, 398 &recent_mt_fops, t); 399 if (pde == NULL) { 400 recent_table_free(t); 401 ret = -ENOMEM; 402 goto out; 403 } 404 pde->uid = uid; 405 pde->gid = gid; 406 #endif 407 spin_lock_bh(&recent_lock); 408 list_add_tail(&t->list, &recent_net->tables); 409 spin_unlock_bh(&recent_lock); 410 ret = 0; 411 out: 412 mutex_unlock(&recent_mutex); 413 return ret; 414 } 415 416 static int recent_mt_check_v0(const struct xt_mtchk_param *par) 417 { 418 const struct xt_recent_mtinfo_v0 *info_v0 = par->matchinfo; 419 struct xt_recent_mtinfo_v1 info_v1; 420 421 /* Copy revision 0 structure to revision 1 */ 422 memcpy(&info_v1, info_v0, sizeof(struct xt_recent_mtinfo)); 423 /* Set default mask to ensure backward compatible behaviour */ 424 memset(info_v1.mask.all, 0xFF, sizeof(info_v1.mask.all)); 425 426 return recent_mt_check(par, &info_v1); 427 } 428 429 static int recent_mt_check_v1(const struct xt_mtchk_param *par) 430 { 431 return recent_mt_check(par, par->matchinfo); 432 } 433 434 static void recent_mt_destroy(const struct xt_mtdtor_param *par) 435 { 436 struct recent_net *recent_net = recent_pernet(par->net); 437 const struct xt_recent_mtinfo_v1 *info = par->matchinfo; 438 struct recent_table *t; 439 440 mutex_lock(&recent_mutex); 441 t = recent_table_lookup(recent_net, info->name); 442 if (--t->refcnt == 0) { 443 spin_lock_bh(&recent_lock); 444 list_del(&t->list); 445 spin_unlock_bh(&recent_lock); 446 #ifdef CONFIG_PROC_FS 447 if (recent_net->xt_recent != NULL) 448 remove_proc_entry(t->name, recent_net->xt_recent); 449 #endif 450 recent_table_flush(t); 451 recent_table_free(t); 452 } 453 mutex_unlock(&recent_mutex); 454 } 455 456 #ifdef CONFIG_PROC_FS 457 struct recent_iter_state { 458 const struct recent_table *table; 459 unsigned int bucket; 460 }; 461 462 static void *recent_seq_start(struct seq_file *seq, loff_t *pos) 463 __acquires(recent_lock) 464 { 465 struct recent_iter_state *st = seq->private; 466 const struct recent_table *t = st->table; 467 struct recent_entry *e; 468 loff_t p = *pos; 469 470 spin_lock_bh(&recent_lock); 471 472 for (st->bucket = 0; st->bucket < ip_list_hash_size; st->bucket++) 473 list_for_each_entry(e, &t->iphash[st->bucket], list) 474 if (p-- == 0) 475 return e; 476 return NULL; 477 } 478 479 static void *recent_seq_next(struct seq_file *seq, void *v, loff_t *pos) 480 { 481 struct recent_iter_state *st = seq->private; 482 const struct recent_table *t = st->table; 483 const struct recent_entry *e = v; 484 const struct list_head *head = e->list.next; 485 486 while (head == &t->iphash[st->bucket]) { 487 if (++st->bucket >= ip_list_hash_size) 488 return NULL; 489 head = t->iphash[st->bucket].next; 490 } 491 (*pos)++; 492 return list_entry(head, struct recent_entry, list); 493 } 494 495 static void recent_seq_stop(struct seq_file *s, void *v) 496 __releases(recent_lock) 497 { 498 spin_unlock_bh(&recent_lock); 499 } 500 501 static int recent_seq_show(struct seq_file *seq, void *v) 502 { 503 const struct recent_entry *e = v; 504 unsigned int i; 505 506 i = (e->index - 1) % ip_pkt_list_tot; 507 if (e->family == NFPROTO_IPV4) 508 seq_printf(seq, "src=%pI4 ttl: %u last_seen: %lu oldest_pkt: %u", 509 &e->addr.ip, e->ttl, e->stamps[i], e->index); 510 else 511 seq_printf(seq, "src=%pI6 ttl: %u last_seen: %lu oldest_pkt: %u", 512 &e->addr.in6, e->ttl, e->stamps[i], e->index); 513 for (i = 0; i < e->nstamps; i++) 514 seq_printf(seq, "%s %lu", i ? "," : "", e->stamps[i]); 515 seq_printf(seq, "\n"); 516 return 0; 517 } 518 519 static const struct seq_operations recent_seq_ops = { 520 .start = recent_seq_start, 521 .next = recent_seq_next, 522 .stop = recent_seq_stop, 523 .show = recent_seq_show, 524 }; 525 526 static int recent_seq_open(struct inode *inode, struct file *file) 527 { 528 struct proc_dir_entry *pde = PDE(inode); 529 struct recent_iter_state *st; 530 531 st = __seq_open_private(file, &recent_seq_ops, sizeof(*st)); 532 if (st == NULL) 533 return -ENOMEM; 534 535 st->table = pde->data; 536 return 0; 537 } 538 539 static ssize_t 540 recent_mt_proc_write(struct file *file, const char __user *input, 541 size_t size, loff_t *loff) 542 { 543 const struct proc_dir_entry *pde = PDE(file->f_path.dentry->d_inode); 544 struct recent_table *t = pde->data; 545 struct recent_entry *e; 546 char buf[sizeof("+b335:1d35:1e55:dead:c0de:1715:5afe:c0de")]; 547 const char *c = buf; 548 union nf_inet_addr addr = {}; 549 u_int16_t family; 550 bool add, succ; 551 552 if (size == 0) 553 return 0; 554 if (size > sizeof(buf)) 555 size = sizeof(buf); 556 if (copy_from_user(buf, input, size) != 0) 557 return -EFAULT; 558 559 /* Strict protocol! */ 560 if (*loff != 0) 561 return -ESPIPE; 562 switch (*c) { 563 case '/': /* flush table */ 564 spin_lock_bh(&recent_lock); 565 recent_table_flush(t); 566 spin_unlock_bh(&recent_lock); 567 return size; 568 case '-': /* remove address */ 569 add = false; 570 break; 571 case '+': /* add address */ 572 add = true; 573 break; 574 default: 575 pr_info("Need \"+ip\", \"-ip\" or \"/\"\n"); 576 return -EINVAL; 577 } 578 579 ++c; 580 --size; 581 if (strnchr(c, size, ':') != NULL) { 582 family = NFPROTO_IPV6; 583 succ = in6_pton(c, size, (void *)&addr, '\n', NULL); 584 } else { 585 family = NFPROTO_IPV4; 586 succ = in4_pton(c, size, (void *)&addr, '\n', NULL); 587 } 588 589 if (!succ) { 590 pr_info("illegal address written to procfs\n"); 591 return -EINVAL; 592 } 593 594 spin_lock_bh(&recent_lock); 595 e = recent_entry_lookup(t, &addr, family, 0); 596 if (e == NULL) { 597 if (add) 598 recent_entry_init(t, &addr, family, 0); 599 } else { 600 if (add) 601 recent_entry_update(t, e); 602 else 603 recent_entry_remove(t, e); 604 } 605 spin_unlock_bh(&recent_lock); 606 /* Note we removed one above */ 607 *loff += size + 1; 608 return size + 1; 609 } 610 611 static const struct file_operations recent_mt_fops = { 612 .open = recent_seq_open, 613 .read = seq_read, 614 .write = recent_mt_proc_write, 615 .release = seq_release_private, 616 .owner = THIS_MODULE, 617 .llseek = seq_lseek, 618 }; 619 620 static int __net_init recent_proc_net_init(struct net *net) 621 { 622 struct recent_net *recent_net = recent_pernet(net); 623 624 recent_net->xt_recent = proc_mkdir("xt_recent", net->proc_net); 625 if (!recent_net->xt_recent) 626 return -ENOMEM; 627 return 0; 628 } 629 630 static void __net_exit recent_proc_net_exit(struct net *net) 631 { 632 struct recent_net *recent_net = recent_pernet(net); 633 struct recent_table *t; 634 635 /* recent_net_exit() is called before recent_mt_destroy(). Make sure 636 * that the parent xt_recent proc entry is is empty before trying to 637 * remove it. 638 */ 639 spin_lock_bh(&recent_lock); 640 list_for_each_entry(t, &recent_net->tables, list) 641 remove_proc_entry(t->name, recent_net->xt_recent); 642 643 recent_net->xt_recent = NULL; 644 spin_unlock_bh(&recent_lock); 645 646 proc_net_remove(net, "xt_recent"); 647 } 648 #else 649 static inline int recent_proc_net_init(struct net *net) 650 { 651 return 0; 652 } 653 654 static inline void recent_proc_net_exit(struct net *net) 655 { 656 } 657 #endif /* CONFIG_PROC_FS */ 658 659 static int __net_init recent_net_init(struct net *net) 660 { 661 struct recent_net *recent_net = recent_pernet(net); 662 663 INIT_LIST_HEAD(&recent_net->tables); 664 return recent_proc_net_init(net); 665 } 666 667 static void __net_exit recent_net_exit(struct net *net) 668 { 669 recent_proc_net_exit(net); 670 } 671 672 static struct pernet_operations recent_net_ops = { 673 .init = recent_net_init, 674 .exit = recent_net_exit, 675 .id = &recent_net_id, 676 .size = sizeof(struct recent_net), 677 }; 678 679 static struct xt_match recent_mt_reg[] __read_mostly = { 680 { 681 .name = "recent", 682 .revision = 0, 683 .family = NFPROTO_IPV4, 684 .match = recent_mt, 685 .matchsize = sizeof(struct xt_recent_mtinfo), 686 .checkentry = recent_mt_check_v0, 687 .destroy = recent_mt_destroy, 688 .me = THIS_MODULE, 689 }, 690 { 691 .name = "recent", 692 .revision = 0, 693 .family = NFPROTO_IPV6, 694 .match = recent_mt, 695 .matchsize = sizeof(struct xt_recent_mtinfo), 696 .checkentry = recent_mt_check_v0, 697 .destroy = recent_mt_destroy, 698 .me = THIS_MODULE, 699 }, 700 { 701 .name = "recent", 702 .revision = 1, 703 .family = NFPROTO_IPV4, 704 .match = recent_mt, 705 .matchsize = sizeof(struct xt_recent_mtinfo_v1), 706 .checkentry = recent_mt_check_v1, 707 .destroy = recent_mt_destroy, 708 .me = THIS_MODULE, 709 }, 710 { 711 .name = "recent", 712 .revision = 1, 713 .family = NFPROTO_IPV6, 714 .match = recent_mt, 715 .matchsize = sizeof(struct xt_recent_mtinfo_v1), 716 .checkentry = recent_mt_check_v1, 717 .destroy = recent_mt_destroy, 718 .me = THIS_MODULE, 719 } 720 }; 721 722 static int __init recent_mt_init(void) 723 { 724 int err; 725 726 if (!ip_list_tot || !ip_pkt_list_tot || ip_pkt_list_tot > 255) 727 return -EINVAL; 728 ip_list_hash_size = 1 << fls(ip_list_tot); 729 730 err = register_pernet_subsys(&recent_net_ops); 731 if (err) 732 return err; 733 err = xt_register_matches(recent_mt_reg, ARRAY_SIZE(recent_mt_reg)); 734 if (err) 735 unregister_pernet_subsys(&recent_net_ops); 736 return err; 737 } 738 739 static void __exit recent_mt_exit(void) 740 { 741 xt_unregister_matches(recent_mt_reg, ARRAY_SIZE(recent_mt_reg)); 742 unregister_pernet_subsys(&recent_net_ops); 743 } 744 745 module_init(recent_mt_init); 746 module_exit(recent_mt_exit); 747