1 // SPDX-License-Identifier: GPL-2.0-only 2 /* 3 * Copyright (c) 2006 Patrick McHardy <kaber@trash.net> 4 * Copyright © CC Computer Consultants GmbH, 2007 - 2008 5 * 6 * This is a replacement of the old ipt_recent module, which carried the 7 * following copyright notice: 8 * 9 * Author: Stephen Frost <sfrost@snowman.net> 10 * Copyright 2002-2003, Stephen Frost, 2.5.x port by laforge@netfilter.org 11 */ 12 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt 13 #include <linux/init.h> 14 #include <linux/ip.h> 15 #include <linux/ipv6.h> 16 #include <linux/module.h> 17 #include <linux/moduleparam.h> 18 #include <linux/proc_fs.h> 19 #include <linux/seq_file.h> 20 #include <linux/string.h> 21 #include <linux/ctype.h> 22 #include <linux/list.h> 23 #include <linux/random.h> 24 #include <linux/jhash.h> 25 #include <linux/bitops.h> 26 #include <linux/skbuff.h> 27 #include <linux/inet.h> 28 #include <linux/slab.h> 29 #include <linux/vmalloc.h> 30 #include <net/net_namespace.h> 31 #include <net/netns/generic.h> 32 33 #include <linux/netfilter/x_tables.h> 34 #include <linux/netfilter/xt_recent.h> 35 36 MODULE_AUTHOR("Patrick McHardy <kaber@trash.net>"); 37 MODULE_AUTHOR("Jan Engelhardt <jengelh@medozas.de>"); 38 MODULE_DESCRIPTION("Xtables: \"recently-seen\" host matching"); 39 MODULE_LICENSE("GPL"); 40 MODULE_ALIAS("ipt_recent"); 41 MODULE_ALIAS("ip6t_recent"); 42 43 static unsigned int ip_list_tot __read_mostly = 100; 44 static unsigned int ip_list_hash_size __read_mostly; 45 static unsigned int ip_list_perms __read_mostly = 0644; 46 static unsigned int ip_list_uid __read_mostly; 47 static unsigned int ip_list_gid __read_mostly; 48 module_param(ip_list_tot, uint, 0400); 49 module_param(ip_list_hash_size, uint, 0400); 50 module_param(ip_list_perms, uint, 0400); 51 module_param(ip_list_uid, uint, 0644); 52 module_param(ip_list_gid, uint, 0644); 53 MODULE_PARM_DESC(ip_list_tot, "number of IPs to remember per list"); 54 MODULE_PARM_DESC(ip_list_hash_size, "size of hash table used to look up IPs"); 55 MODULE_PARM_DESC(ip_list_perms, "permissions on /proc/net/xt_recent/* files"); 56 MODULE_PARM_DESC(ip_list_uid, "default owner of /proc/net/xt_recent/* files"); 57 MODULE_PARM_DESC(ip_list_gid, "default owning group of /proc/net/xt_recent/* files"); 58 59 /* retained for backwards compatibility */ 60 static unsigned int ip_pkt_list_tot __read_mostly; 61 module_param(ip_pkt_list_tot, uint, 0400); 62 MODULE_PARM_DESC(ip_pkt_list_tot, "number of packets per IP address to remember (max. 255)"); 63 64 #define XT_RECENT_MAX_NSTAMPS 256 65 66 struct recent_entry { 67 struct list_head list; 68 struct list_head lru_list; 69 union nf_inet_addr addr; 70 u_int16_t family; 71 u_int8_t ttl; 72 u_int8_t index; 73 u_int16_t nstamps; 74 unsigned long stamps[0]; 75 }; 76 77 struct recent_table { 78 struct list_head list; 79 char name[XT_RECENT_NAME_LEN]; 80 union nf_inet_addr mask; 81 unsigned int refcnt; 82 unsigned int entries; 83 u8 nstamps_max_mask; 84 struct list_head lru_list; 85 struct list_head iphash[0]; 86 }; 87 88 struct recent_net { 89 struct list_head tables; 90 #ifdef CONFIG_PROC_FS 91 struct proc_dir_entry *xt_recent; 92 #endif 93 }; 94 95 static unsigned int recent_net_id __read_mostly; 96 97 static inline struct recent_net *recent_pernet(struct net *net) 98 { 99 return net_generic(net, recent_net_id); 100 } 101 102 static DEFINE_SPINLOCK(recent_lock); 103 static DEFINE_MUTEX(recent_mutex); 104 105 #ifdef CONFIG_PROC_FS 106 static const struct file_operations recent_mt_fops; 107 #endif 108 109 static u_int32_t hash_rnd __read_mostly; 110 111 static inline unsigned int recent_entry_hash4(const union nf_inet_addr *addr) 112 { 113 return jhash_1word((__force u32)addr->ip, hash_rnd) & 114 (ip_list_hash_size - 1); 115 } 116 117 static inline unsigned int recent_entry_hash6(const union nf_inet_addr *addr) 118 { 119 return jhash2((u32 *)addr->ip6, ARRAY_SIZE(addr->ip6), hash_rnd) & 120 (ip_list_hash_size - 1); 121 } 122 123 static struct recent_entry * 124 recent_entry_lookup(const struct recent_table *table, 125 const union nf_inet_addr *addrp, u_int16_t family, 126 u_int8_t ttl) 127 { 128 struct recent_entry *e; 129 unsigned int h; 130 131 if (family == NFPROTO_IPV4) 132 h = recent_entry_hash4(addrp); 133 else 134 h = recent_entry_hash6(addrp); 135 136 list_for_each_entry(e, &table->iphash[h], list) 137 if (e->family == family && 138 memcmp(&e->addr, addrp, sizeof(e->addr)) == 0 && 139 (ttl == e->ttl || ttl == 0 || e->ttl == 0)) 140 return e; 141 return NULL; 142 } 143 144 static void recent_entry_remove(struct recent_table *t, struct recent_entry *e) 145 { 146 list_del(&e->list); 147 list_del(&e->lru_list); 148 kfree(e); 149 t->entries--; 150 } 151 152 /* 153 * Drop entries with timestamps older then 'time'. 154 */ 155 static void recent_entry_reap(struct recent_table *t, unsigned long time) 156 { 157 struct recent_entry *e; 158 159 /* 160 * The head of the LRU list is always the oldest entry. 161 */ 162 e = list_entry(t->lru_list.next, struct recent_entry, lru_list); 163 164 /* 165 * The last time stamp is the most recent. 166 */ 167 if (time_after(time, e->stamps[e->index-1])) 168 recent_entry_remove(t, e); 169 } 170 171 static struct recent_entry * 172 recent_entry_init(struct recent_table *t, const union nf_inet_addr *addr, 173 u_int16_t family, u_int8_t ttl) 174 { 175 struct recent_entry *e; 176 unsigned int nstamps_max = t->nstamps_max_mask; 177 178 if (t->entries >= ip_list_tot) { 179 e = list_entry(t->lru_list.next, struct recent_entry, lru_list); 180 recent_entry_remove(t, e); 181 } 182 183 nstamps_max += 1; 184 e = kmalloc(struct_size(e, stamps, nstamps_max), GFP_ATOMIC); 185 if (e == NULL) 186 return NULL; 187 memcpy(&e->addr, addr, sizeof(e->addr)); 188 e->ttl = ttl; 189 e->stamps[0] = jiffies; 190 e->nstamps = 1; 191 e->index = 1; 192 e->family = family; 193 if (family == NFPROTO_IPV4) 194 list_add_tail(&e->list, &t->iphash[recent_entry_hash4(addr)]); 195 else 196 list_add_tail(&e->list, &t->iphash[recent_entry_hash6(addr)]); 197 list_add_tail(&e->lru_list, &t->lru_list); 198 t->entries++; 199 return e; 200 } 201 202 static void recent_entry_update(struct recent_table *t, struct recent_entry *e) 203 { 204 e->index &= t->nstamps_max_mask; 205 e->stamps[e->index++] = jiffies; 206 if (e->index > e->nstamps) 207 e->nstamps = e->index; 208 list_move_tail(&e->lru_list, &t->lru_list); 209 } 210 211 static struct recent_table *recent_table_lookup(struct recent_net *recent_net, 212 const char *name) 213 { 214 struct recent_table *t; 215 216 list_for_each_entry(t, &recent_net->tables, list) 217 if (!strcmp(t->name, name)) 218 return t; 219 return NULL; 220 } 221 222 static void recent_table_flush(struct recent_table *t) 223 { 224 struct recent_entry *e, *next; 225 unsigned int i; 226 227 for (i = 0; i < ip_list_hash_size; i++) 228 list_for_each_entry_safe(e, next, &t->iphash[i], list) 229 recent_entry_remove(t, e); 230 } 231 232 static bool 233 recent_mt(const struct sk_buff *skb, struct xt_action_param *par) 234 { 235 struct net *net = xt_net(par); 236 struct recent_net *recent_net = recent_pernet(net); 237 const struct xt_recent_mtinfo_v1 *info = par->matchinfo; 238 struct recent_table *t; 239 struct recent_entry *e; 240 union nf_inet_addr addr = {}, addr_mask; 241 u_int8_t ttl; 242 bool ret = info->invert; 243 244 if (xt_family(par) == NFPROTO_IPV4) { 245 const struct iphdr *iph = ip_hdr(skb); 246 247 if (info->side == XT_RECENT_DEST) 248 addr.ip = iph->daddr; 249 else 250 addr.ip = iph->saddr; 251 252 ttl = iph->ttl; 253 } else { 254 const struct ipv6hdr *iph = ipv6_hdr(skb); 255 256 if (info->side == XT_RECENT_DEST) 257 memcpy(&addr.in6, &iph->daddr, sizeof(addr.in6)); 258 else 259 memcpy(&addr.in6, &iph->saddr, sizeof(addr.in6)); 260 261 ttl = iph->hop_limit; 262 } 263 264 /* use TTL as seen before forwarding */ 265 if (xt_out(par) != NULL && 266 (!skb->sk || !net_eq(net, sock_net(skb->sk)))) 267 ttl++; 268 269 spin_lock_bh(&recent_lock); 270 t = recent_table_lookup(recent_net, info->name); 271 272 nf_inet_addr_mask(&addr, &addr_mask, &t->mask); 273 274 e = recent_entry_lookup(t, &addr_mask, xt_family(par), 275 (info->check_set & XT_RECENT_TTL) ? ttl : 0); 276 if (e == NULL) { 277 if (!(info->check_set & XT_RECENT_SET)) 278 goto out; 279 e = recent_entry_init(t, &addr_mask, xt_family(par), ttl); 280 if (e == NULL) 281 par->hotdrop = true; 282 ret = !ret; 283 goto out; 284 } 285 286 if (info->check_set & XT_RECENT_SET) 287 ret = !ret; 288 else if (info->check_set & XT_RECENT_REMOVE) { 289 recent_entry_remove(t, e); 290 ret = !ret; 291 } else if (info->check_set & (XT_RECENT_CHECK | XT_RECENT_UPDATE)) { 292 unsigned long time = jiffies - info->seconds * HZ; 293 unsigned int i, hits = 0; 294 295 for (i = 0; i < e->nstamps; i++) { 296 if (info->seconds && time_after(time, e->stamps[i])) 297 continue; 298 if (!info->hit_count || ++hits >= info->hit_count) { 299 ret = !ret; 300 break; 301 } 302 } 303 304 /* info->seconds must be non-zero */ 305 if (info->check_set & XT_RECENT_REAP) 306 recent_entry_reap(t, time); 307 } 308 309 if (info->check_set & XT_RECENT_SET || 310 (info->check_set & XT_RECENT_UPDATE && ret)) { 311 recent_entry_update(t, e); 312 e->ttl = ttl; 313 } 314 out: 315 spin_unlock_bh(&recent_lock); 316 return ret; 317 } 318 319 static void recent_table_free(void *addr) 320 { 321 kvfree(addr); 322 } 323 324 static int recent_mt_check(const struct xt_mtchk_param *par, 325 const struct xt_recent_mtinfo_v1 *info) 326 { 327 struct recent_net *recent_net = recent_pernet(par->net); 328 struct recent_table *t; 329 #ifdef CONFIG_PROC_FS 330 struct proc_dir_entry *pde; 331 kuid_t uid; 332 kgid_t gid; 333 #endif 334 unsigned int nstamp_mask; 335 unsigned int i; 336 int ret = -EINVAL; 337 338 net_get_random_once(&hash_rnd, sizeof(hash_rnd)); 339 340 if (info->check_set & ~XT_RECENT_VALID_FLAGS) { 341 pr_info_ratelimited("Unsupported userspace 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 >= XT_RECENT_MAX_NSTAMPS) { 356 pr_info_ratelimited("hitcount (%u) is larger than allowed maximum (%u)\n", 357 info->hit_count, XT_RECENT_MAX_NSTAMPS - 1); 358 return -EINVAL; 359 } 360 ret = xt_check_proc_name(info->name, sizeof(info->name)); 361 if (ret) 362 return ret; 363 364 if (ip_pkt_list_tot && info->hit_count < ip_pkt_list_tot) 365 nstamp_mask = roundup_pow_of_two(ip_pkt_list_tot) - 1; 366 else if (info->hit_count) 367 nstamp_mask = roundup_pow_of_two(info->hit_count) - 1; 368 else 369 nstamp_mask = 32 - 1; 370 371 mutex_lock(&recent_mutex); 372 t = recent_table_lookup(recent_net, info->name); 373 if (t != NULL) { 374 if (nstamp_mask > t->nstamps_max_mask) { 375 spin_lock_bh(&recent_lock); 376 recent_table_flush(t); 377 t->nstamps_max_mask = nstamp_mask; 378 spin_unlock_bh(&recent_lock); 379 } 380 381 t->refcnt++; 382 ret = 0; 383 goto out; 384 } 385 386 t = kvzalloc(struct_size(t, iphash, ip_list_hash_size), GFP_KERNEL); 387 if (t == NULL) { 388 ret = -ENOMEM; 389 goto out; 390 } 391 t->refcnt = 1; 392 t->nstamps_max_mask = nstamp_mask; 393 394 memcpy(&t->mask, &info->mask, sizeof(t->mask)); 395 strcpy(t->name, info->name); 396 INIT_LIST_HEAD(&t->lru_list); 397 for (i = 0; i < ip_list_hash_size; i++) 398 INIT_LIST_HEAD(&t->iphash[i]); 399 #ifdef CONFIG_PROC_FS 400 uid = make_kuid(&init_user_ns, ip_list_uid); 401 gid = make_kgid(&init_user_ns, ip_list_gid); 402 if (!uid_valid(uid) || !gid_valid(gid)) { 403 recent_table_free(t); 404 ret = -EINVAL; 405 goto out; 406 } 407 pde = proc_create_data(t->name, ip_list_perms, recent_net->xt_recent, 408 &recent_mt_fops, t); 409 if (pde == NULL) { 410 recent_table_free(t); 411 ret = -ENOMEM; 412 goto out; 413 } 414 proc_set_user(pde, uid, gid); 415 #endif 416 spin_lock_bh(&recent_lock); 417 list_add_tail(&t->list, &recent_net->tables); 418 spin_unlock_bh(&recent_lock); 419 ret = 0; 420 out: 421 mutex_unlock(&recent_mutex); 422 return ret; 423 } 424 425 static int recent_mt_check_v0(const struct xt_mtchk_param *par) 426 { 427 const struct xt_recent_mtinfo_v0 *info_v0 = par->matchinfo; 428 struct xt_recent_mtinfo_v1 info_v1; 429 430 /* Copy revision 0 structure to revision 1 */ 431 memcpy(&info_v1, info_v0, sizeof(struct xt_recent_mtinfo)); 432 /* Set default mask to ensure backward compatible behaviour */ 433 memset(info_v1.mask.all, 0xFF, sizeof(info_v1.mask.all)); 434 435 return recent_mt_check(par, &info_v1); 436 } 437 438 static int recent_mt_check_v1(const struct xt_mtchk_param *par) 439 { 440 return recent_mt_check(par, par->matchinfo); 441 } 442 443 static void recent_mt_destroy(const struct xt_mtdtor_param *par) 444 { 445 struct recent_net *recent_net = recent_pernet(par->net); 446 const struct xt_recent_mtinfo_v1 *info = par->matchinfo; 447 struct recent_table *t; 448 449 mutex_lock(&recent_mutex); 450 t = recent_table_lookup(recent_net, info->name); 451 if (--t->refcnt == 0) { 452 spin_lock_bh(&recent_lock); 453 list_del(&t->list); 454 spin_unlock_bh(&recent_lock); 455 #ifdef CONFIG_PROC_FS 456 if (recent_net->xt_recent != NULL) 457 remove_proc_entry(t->name, recent_net->xt_recent); 458 #endif 459 recent_table_flush(t); 460 recent_table_free(t); 461 } 462 mutex_unlock(&recent_mutex); 463 } 464 465 #ifdef CONFIG_PROC_FS 466 struct recent_iter_state { 467 const struct recent_table *table; 468 unsigned int bucket; 469 }; 470 471 static void *recent_seq_start(struct seq_file *seq, loff_t *pos) 472 __acquires(recent_lock) 473 { 474 struct recent_iter_state *st = seq->private; 475 const struct recent_table *t = st->table; 476 struct recent_entry *e; 477 loff_t p = *pos; 478 479 spin_lock_bh(&recent_lock); 480 481 for (st->bucket = 0; st->bucket < ip_list_hash_size; st->bucket++) 482 list_for_each_entry(e, &t->iphash[st->bucket], list) 483 if (p-- == 0) 484 return e; 485 return NULL; 486 } 487 488 static void *recent_seq_next(struct seq_file *seq, void *v, loff_t *pos) 489 { 490 struct recent_iter_state *st = seq->private; 491 const struct recent_table *t = st->table; 492 const struct recent_entry *e = v; 493 const struct list_head *head = e->list.next; 494 495 while (head == &t->iphash[st->bucket]) { 496 if (++st->bucket >= ip_list_hash_size) 497 return NULL; 498 head = t->iphash[st->bucket].next; 499 } 500 (*pos)++; 501 return list_entry(head, struct recent_entry, list); 502 } 503 504 static void recent_seq_stop(struct seq_file *s, void *v) 505 __releases(recent_lock) 506 { 507 spin_unlock_bh(&recent_lock); 508 } 509 510 static int recent_seq_show(struct seq_file *seq, void *v) 511 { 512 const struct recent_entry *e = v; 513 struct recent_iter_state *st = seq->private; 514 const struct recent_table *t = st->table; 515 unsigned int i; 516 517 i = (e->index - 1) & t->nstamps_max_mask; 518 519 if (e->family == NFPROTO_IPV4) 520 seq_printf(seq, "src=%pI4 ttl: %u last_seen: %lu oldest_pkt: %u", 521 &e->addr.ip, e->ttl, e->stamps[i], e->index); 522 else 523 seq_printf(seq, "src=%pI6 ttl: %u last_seen: %lu oldest_pkt: %u", 524 &e->addr.in6, e->ttl, e->stamps[i], e->index); 525 for (i = 0; i < e->nstamps; i++) 526 seq_printf(seq, "%s %lu", i ? "," : "", e->stamps[i]); 527 seq_putc(seq, '\n'); 528 return 0; 529 } 530 531 static const struct seq_operations recent_seq_ops = { 532 .start = recent_seq_start, 533 .next = recent_seq_next, 534 .stop = recent_seq_stop, 535 .show = recent_seq_show, 536 }; 537 538 static int recent_seq_open(struct inode *inode, struct file *file) 539 { 540 struct recent_iter_state *st; 541 542 st = __seq_open_private(file, &recent_seq_ops, sizeof(*st)); 543 if (st == NULL) 544 return -ENOMEM; 545 546 st->table = PDE_DATA(inode); 547 return 0; 548 } 549 550 static ssize_t 551 recent_mt_proc_write(struct file *file, const char __user *input, 552 size_t size, loff_t *loff) 553 { 554 struct recent_table *t = PDE_DATA(file_inode(file)); 555 struct recent_entry *e; 556 char buf[sizeof("+b335:1d35:1e55:dead:c0de:1715:5afe:c0de")]; 557 const char *c = buf; 558 union nf_inet_addr addr = {}; 559 u_int16_t family; 560 bool add, succ; 561 562 if (size == 0) 563 return 0; 564 if (size > sizeof(buf)) 565 size = sizeof(buf); 566 if (copy_from_user(buf, input, size) != 0) 567 return -EFAULT; 568 569 /* Strict protocol! */ 570 if (*loff != 0) 571 return -ESPIPE; 572 switch (*c) { 573 case '/': /* flush table */ 574 spin_lock_bh(&recent_lock); 575 recent_table_flush(t); 576 spin_unlock_bh(&recent_lock); 577 return size; 578 case '-': /* remove address */ 579 add = false; 580 break; 581 case '+': /* add address */ 582 add = true; 583 break; 584 default: 585 pr_info_ratelimited("Need \"+ip\", \"-ip\" or \"/\"\n"); 586 return -EINVAL; 587 } 588 589 ++c; 590 --size; 591 if (strnchr(c, size, ':') != NULL) { 592 family = NFPROTO_IPV6; 593 succ = in6_pton(c, size, (void *)&addr, '\n', NULL); 594 } else { 595 family = NFPROTO_IPV4; 596 succ = in4_pton(c, size, (void *)&addr, '\n', NULL); 597 } 598 599 if (!succ) 600 return -EINVAL; 601 602 spin_lock_bh(&recent_lock); 603 e = recent_entry_lookup(t, &addr, family, 0); 604 if (e == NULL) { 605 if (add) 606 recent_entry_init(t, &addr, family, 0); 607 } else { 608 if (add) 609 recent_entry_update(t, e); 610 else 611 recent_entry_remove(t, e); 612 } 613 spin_unlock_bh(&recent_lock); 614 /* Note we removed one above */ 615 *loff += size + 1; 616 return size + 1; 617 } 618 619 static const struct file_operations recent_mt_fops = { 620 .open = recent_seq_open, 621 .read = seq_read, 622 .write = recent_mt_proc_write, 623 .release = seq_release_private, 624 .owner = THIS_MODULE, 625 .llseek = seq_lseek, 626 }; 627 628 static int __net_init recent_proc_net_init(struct net *net) 629 { 630 struct recent_net *recent_net = recent_pernet(net); 631 632 recent_net->xt_recent = proc_mkdir("xt_recent", net->proc_net); 633 if (!recent_net->xt_recent) 634 return -ENOMEM; 635 return 0; 636 } 637 638 static void __net_exit recent_proc_net_exit(struct net *net) 639 { 640 struct recent_net *recent_net = recent_pernet(net); 641 struct recent_table *t; 642 643 /* recent_net_exit() is called before recent_mt_destroy(). Make sure 644 * that the parent xt_recent proc entry is is empty before trying to 645 * remove it. 646 */ 647 spin_lock_bh(&recent_lock); 648 list_for_each_entry(t, &recent_net->tables, list) 649 remove_proc_entry(t->name, recent_net->xt_recent); 650 651 recent_net->xt_recent = NULL; 652 spin_unlock_bh(&recent_lock); 653 654 remove_proc_entry("xt_recent", net->proc_net); 655 } 656 #else 657 static inline int recent_proc_net_init(struct net *net) 658 { 659 return 0; 660 } 661 662 static inline void recent_proc_net_exit(struct net *net) 663 { 664 } 665 #endif /* CONFIG_PROC_FS */ 666 667 static int __net_init recent_net_init(struct net *net) 668 { 669 struct recent_net *recent_net = recent_pernet(net); 670 671 INIT_LIST_HEAD(&recent_net->tables); 672 return recent_proc_net_init(net); 673 } 674 675 static void __net_exit recent_net_exit(struct net *net) 676 { 677 recent_proc_net_exit(net); 678 } 679 680 static struct pernet_operations recent_net_ops = { 681 .init = recent_net_init, 682 .exit = recent_net_exit, 683 .id = &recent_net_id, 684 .size = sizeof(struct recent_net), 685 }; 686 687 static struct xt_match recent_mt_reg[] __read_mostly = { 688 { 689 .name = "recent", 690 .revision = 0, 691 .family = NFPROTO_IPV4, 692 .match = recent_mt, 693 .matchsize = sizeof(struct xt_recent_mtinfo), 694 .checkentry = recent_mt_check_v0, 695 .destroy = recent_mt_destroy, 696 .me = THIS_MODULE, 697 }, 698 { 699 .name = "recent", 700 .revision = 0, 701 .family = NFPROTO_IPV6, 702 .match = recent_mt, 703 .matchsize = sizeof(struct xt_recent_mtinfo), 704 .checkentry = recent_mt_check_v0, 705 .destroy = recent_mt_destroy, 706 .me = THIS_MODULE, 707 }, 708 { 709 .name = "recent", 710 .revision = 1, 711 .family = NFPROTO_IPV4, 712 .match = recent_mt, 713 .matchsize = sizeof(struct xt_recent_mtinfo_v1), 714 .checkentry = recent_mt_check_v1, 715 .destroy = recent_mt_destroy, 716 .me = THIS_MODULE, 717 }, 718 { 719 .name = "recent", 720 .revision = 1, 721 .family = NFPROTO_IPV6, 722 .match = recent_mt, 723 .matchsize = sizeof(struct xt_recent_mtinfo_v1), 724 .checkentry = recent_mt_check_v1, 725 .destroy = recent_mt_destroy, 726 .me = THIS_MODULE, 727 } 728 }; 729 730 static int __init recent_mt_init(void) 731 { 732 int err; 733 734 BUILD_BUG_ON_NOT_POWER_OF_2(XT_RECENT_MAX_NSTAMPS); 735 736 if (!ip_list_tot || ip_pkt_list_tot >= XT_RECENT_MAX_NSTAMPS) 737 return -EINVAL; 738 ip_list_hash_size = 1 << fls(ip_list_tot); 739 740 err = register_pernet_subsys(&recent_net_ops); 741 if (err) 742 return err; 743 err = xt_register_matches(recent_mt_reg, ARRAY_SIZE(recent_mt_reg)); 744 if (err) 745 unregister_pernet_subsys(&recent_net_ops); 746 return err; 747 } 748 749 static void __exit recent_mt_exit(void) 750 { 751 xt_unregister_matches(recent_mt_reg, ARRAY_SIZE(recent_mt_reg)); 752 unregister_pernet_subsys(&recent_net_ops); 753 } 754 755 module_init(recent_mt_init); 756 module_exit(recent_mt_exit); 757