net/netfilter/ipset/ip_set_hash_ip.c

   1 /* Copyright (C) 2003-2011 Jozsef Kadlecsik <kadlec@blackhole.kfki.hu>
   2  *
   3  * This program is free software; you can redistribute it and/or modify
   4  * it under the terms of the GNU General Public License version 2 as
   5  * published by the Free Software Foundation.
   6  */
   7
   8 /* Kernel module implementing an IP set type: the hash:ip type */
   9
  10 #include <linux/jhash.h>
  11 #include <linux/module.h>
  12 #include <linux/ip.h>
  13 #include <linux/skbuff.h>
  14 #include <linux/errno.h>
  15 #include <linux/random.h>
  16 #include <net/ip.h>
  17 #include <net/ipv6.h>
  18 #include <net/netlink.h>
  19 #include <net/tcp.h>
  20
  21 #include <linux/netfilter.h>
  22 #include <linux/netfilter/ipset/pfxlen.h>
  23 #include <linux/netfilter/ipset/ip_set.h>
  24 #include <linux/netfilter/ipset/ip_set_timeout.h>
  25 #include <linux/netfilter/ipset/ip_set_hash.h>
  26
  27 #define REVISION_MIN    0
  28 #define REVISION_MAX    0
  29
  30 MODULE_LICENSE("GPL");
  31 MODULE_AUTHOR("Jozsef Kadlecsik <kadlec@blackhole.kfki.hu>");
  32 IP_SET_MODULE_DESC("hash:ip", REVISION_MIN, REVISION_MAX);
  33 MODULE_ALIAS("ip_set_hash:ip");
  34
  35 /* Type specific function prefix */
  36 #define TYPE            hash_ip
  37
  38 static bool
  39 hash_ip_same_set(const struct ip_set *a, const struct ip_set *b);
  40
  41 #define hash_ip4_same_set       hash_ip_same_set
  42 #define hash_ip6_same_set       hash_ip_same_set
  43
  44 /* The type variant functions: IPv4 */
  45
  46 /* Member elements without timeout */
  47 struct hash_ip4_elem {
  48         __be32 ip;
  49 };
  50
  51 /* Member elements with timeout support */
  52 struct hash_ip4_telem {
  53         __be32 ip;
  54         unsigned long timeout;
  55 };
  56
  57 static inline bool
  58 hash_ip4_data_equal(const struct hash_ip4_elem *ip1,
  59                     const struct hash_ip4_elem *ip2,
  60                     u32 *multi)
  61 {
  62         return ip1->ip == ip2->ip;
  63 }
  64
  65 static inline bool
  66 hash_ip4_data_isnull(const struct hash_ip4_elem *elem)
  67 {
  68         return elem->ip == 0;
  69 }
  70
  71 static inline void
  72 hash_ip4_data_copy(struct hash_ip4_elem *dst, const struct hash_ip4_elem *src)
  73 {
  74         dst->ip = src->ip;
  75 }
  76
  77 /* Zero valued IP addresses cannot be stored */
  78 static inline void
  79 hash_ip4_data_zero_out(struct hash_ip4_elem *elem)
  80 {
  81         elem->ip = 0;
  82 }
  83
  84 static inline bool
  85 hash_ip4_data_list(struct sk_buff *skb, const struct hash_ip4_elem *data)
  86 {
  87         if (nla_put_ipaddr4(skb, IPSET_ATTR_IP, data->ip))
  88                 goto nla_put_failure;
  89         return 0;
  90
  91 nla_put_failure:
  92         return 1;
  93 }
  94
  95 static bool
  96 hash_ip4_data_tlist(struct sk_buff *skb, const struct hash_ip4_elem *data)
  97 {
  98         const struct hash_ip4_telem *tdata =
  99                 (const struct hash_ip4_telem *)data;
 100
 101         if (nla_put_ipaddr4(skb, IPSET_ATTR_IP, tdata->ip) ||
 102             nla_put_net32(skb, IPSET_ATTR_TIMEOUT,
 103                           htonl(ip_set_timeout_get(tdata->timeout))))
 104                 goto nla_put_failure;
 105
 106         return 0;
 107
 108 nla_put_failure:
 109         return 1;
 110 }
 111
 112 #define IP_SET_HASH_WITH_NETMASK
 113 #define PF              4
 114 #define HOST_MASK       32
 115 #include <linux/netfilter/ipset/ip_set_ahash.h>
 116
 117 static inline void
 118 hash_ip4_data_next(struct ip_set_hash *h, const struct hash_ip4_elem *d)
 119 {
 120         h->next.ip = d->ip;
 121 }
 122
 123 static int
 124 hash_ip4_kadt(struct ip_set *set, const struct sk_buff *skb,
 125               const struct xt_action_param *par,
 126               enum ipset_adt adt, const struct ip_set_adt_opt *opt)
 127 {
 128         const struct ip_set_hash *h = set->data;
 129         ipset_adtfn adtfn = set->variant->adt[adt];
 130         __be32 ip;
 131
 132         ip4addrptr(skb, opt->flags & IPSET_DIM_ONE_SRC, &ip);
 133         ip &= ip_set_netmask(h->netmask);
 134         if (ip == 0)
 135                 return -EINVAL;
 136
 137         return adtfn(set, &ip, opt_timeout(opt, h), opt->cmdflags);
 138 }
 139
 140 static int
 141 hash_ip4_uadt(struct ip_set *set, struct nlattr *tb[],
 142               enum ipset_adt adt, u32 *lineno, u32 flags, bool retried)
 143 {
 144         const struct ip_set_hash *h = set->data;
 145         ipset_adtfn adtfn = set->variant->adt[adt];
 146         u32 ip, ip_to, hosts, timeout = h->timeout;
 147         __be32 nip;
 148         int ret = 0;
 149
 150         if (unlikely(!tb[IPSET_ATTR_IP] ||
 151                      !ip_set_optattr_netorder(tb, IPSET_ATTR_TIMEOUT)))
 152                 return -IPSET_ERR_PROTOCOL;
 153
 154         if (tb[IPSET_ATTR_LINENO])
 155                 *lineno = nla_get_u32(tb[IPSET_ATTR_LINENO]);
 156
 157         ret = ip_set_get_hostipaddr4(tb[IPSET_ATTR_IP], &ip);
 158         if (ret)
 159                 return ret;
 160
 161         ip &= ip_set_hostmask(h->netmask);
 162
 163         if (tb[IPSET_ATTR_TIMEOUT]) {
 164                 if (!with_timeout(h->timeout))
 165                         return -IPSET_ERR_TIMEOUT;
 166                 timeout = ip_set_timeout_uget(tb[IPSET_ATTR_TIMEOUT]);
 167         }
 168
 169         if (adt == IPSET_TEST) {
 170                 nip = htonl(ip);
 171                 if (nip == 0)
 172                         return -IPSET_ERR_HASH_ELEM;
 173                 return adtfn(set, &nip, timeout, flags);
 174         }
 175
 176         ip_to = ip;
 177         if (tb[IPSET_ATTR_IP_TO]) {
 178                 ret = ip_set_get_hostipaddr4(tb[IPSET_ATTR_IP_TO], &ip_to);
 179                 if (ret)
 180                         return ret;
 181                 if (ip > ip_to)
 182                         swap(ip, ip_to);
 183         } else if (tb[IPSET_ATTR_CIDR]) {
 184                 u8 cidr = nla_get_u8(tb[IPSET_ATTR_CIDR]);
 185
 186                 if (!cidr || cidr > 32)
 187                         return -IPSET_ERR_INVALID_CIDR;
 188                 ip_set_mask_from_to(ip, ip_to, cidr);
 189         }
 190
 191         hosts = h->netmask == 32 ? 1 : 2 << (32 - h->netmask - 1);
 192
 193         if (retried)
 194                 ip = ntohl(h->next.ip);
 195         for (; !before(ip_to, ip); ip += hosts) {
 196                 nip = htonl(ip);
 197                 if (nip == 0)
 198                         return -IPSET_ERR_HASH_ELEM;
 199                 ret = adtfn(set, &nip, timeout, flags);
 200
 201                 if (ret && !ip_set_eexist(ret, flags))
 202                         return ret;
 203                 else
 204                         ret = 0;
 205         }
 206         return ret;
 207 }
 208
 209 static bool
 210 hash_ip_same_set(const struct ip_set *a, const struct ip_set *b)
 211 {
 212         const struct ip_set_hash *x = a->data;
 213         const struct ip_set_hash *y = b->data;
 214
 215         /* Resizing changes htable_bits, so we ignore it */
 216         return x->maxelem == y->maxelem &&
 217                x->timeout == y->timeout &&
 218                x->netmask == y->netmask;
 219 }
 220
 221 /* The type variant functions: IPv6 */
 222
 223 struct hash_ip6_elem {
 224         union nf_inet_addr ip;
 225 };
 226
 227 struct hash_ip6_telem {
 228         union nf_inet_addr ip;
 229         unsigned long timeout;
 230 };
 231
 232 static inline bool
 233 hash_ip6_data_equal(const struct hash_ip6_elem *ip1,
 234                     const struct hash_ip6_elem *ip2,
 235                     u32 *multi)
 236 {
 237         return ipv6_addr_equal(&ip1->ip.in6, &ip2->ip.in6);
 238 }
 239
 240 static inline bool
 241 hash_ip6_data_isnull(const struct hash_ip6_elem *elem)
 242 {
 243         return ipv6_addr_any(&elem->ip.in6);
 244 }
 245
 246 static inline void
 247 hash_ip6_data_copy(struct hash_ip6_elem *dst, const struct hash_ip6_elem *src)
 248 {
 249         dst->ip.in6 = src->ip.in6;
 250 }
 251
 252 static inline void
 253 hash_ip6_data_zero_out(struct hash_ip6_elem *elem)
 254 {
 255         ipv6_addr_set(&elem->ip.in6, 0, 0, 0, 0);
 256 }
 257
 258 static inline void
 259 ip6_netmask(union nf_inet_addr *ip, u8 prefix)
 260 {
 261         ip->ip6[0] &= ip_set_netmask6(prefix)[0];
 262         ip->ip6[1] &= ip_set_netmask6(prefix)[1];
 263         ip->ip6[2] &= ip_set_netmask6(prefix)[2];
 264         ip->ip6[3] &= ip_set_netmask6(prefix)[3];
 265 }
 266
 267 static bool
 268 hash_ip6_data_list(struct sk_buff *skb, const struct hash_ip6_elem *data)
 269 {
 270         if (nla_put_ipaddr6(skb, IPSET_ATTR_IP, &data->ip.in6))
 271                 goto nla_put_failure;
 272         return 0;
 273
 274 nla_put_failure:
 275         return 1;
 276 }
 277
 278 static bool
 279 hash_ip6_data_tlist(struct sk_buff *skb, const struct hash_ip6_elem *data)
 280 {
 281         const struct hash_ip6_telem *e =
 282                 (const struct hash_ip6_telem *)data;
 283
 284         if (nla_put_ipaddr6(skb, IPSET_ATTR_IP, &e->ip.in6) ||
 285             nla_put_net32(skb, IPSET_ATTR_TIMEOUT,
 286                           htonl(ip_set_timeout_get(e->timeout))))
 287                 goto nla_put_failure;
 288         return 0;
 289
 290 nla_put_failure:
 291         return 1;
 292 }
 293
 294 #undef PF
 295 #undef HOST_MASK
 296
 297 #define PF              6
 298 #define HOST_MASK       128
 299 #include <linux/netfilter/ipset/ip_set_ahash.h>
 300
 301 static inline void
 302 hash_ip6_data_next(struct ip_set_hash *h, const struct hash_ip6_elem *d)
 303 {
 304 }
 305
 306 static int
 307 hash_ip6_kadt(struct ip_set *set, const struct sk_buff *skb,
 308               const struct xt_action_param *par,
 309               enum ipset_adt adt, const struct ip_set_adt_opt *opt)
 310 {
 311         const struct ip_set_hash *h = set->data;
 312         ipset_adtfn adtfn = set->variant->adt[adt];
 313         union nf_inet_addr ip;
 314
 315         ip6addrptr(skb, opt->flags & IPSET_DIM_ONE_SRC, &ip.in6);
 316         ip6_netmask(&ip, h->netmask);
 317         if (ipv6_addr_any(&ip.in6))
 318                 return -EINVAL;
 319
 320         return adtfn(set, &ip, opt_timeout(opt, h), opt->cmdflags);
 321 }
 322
 323 static const struct nla_policy hash_ip6_adt_policy[IPSET_ATTR_ADT_MAX + 1] = {
 324         [IPSET_ATTR_IP]         = { .type = NLA_NESTED },
 325         [IPSET_ATTR_TIMEOUT]    = { .type = NLA_U32 },
 326         [IPSET_ATTR_LINENO]     = { .type = NLA_U32 },
 327 };
 328
 329 static int
 330 hash_ip6_uadt(struct ip_set *set, struct nlattr *tb[],
 331               enum ipset_adt adt, u32 *lineno, u32 flags, bool retried)
 332 {
 333         const struct ip_set_hash *h = set->data;
 334         ipset_adtfn adtfn = set->variant->adt[adt];
 335         union nf_inet_addr ip;
 336         u32 timeout = h->timeout;
 337         int ret;
 338
 339         if (unlikely(!tb[IPSET_ATTR_IP] ||
 340                      !ip_set_optattr_netorder(tb, IPSET_ATTR_TIMEOUT) ||
 341                      tb[IPSET_ATTR_IP_TO] ||
 342                      tb[IPSET_ATTR_CIDR]))
 343                 return -IPSET_ERR_PROTOCOL;
 344
 345         if (tb[IPSET_ATTR_LINENO])
 346                 *lineno = nla_get_u32(tb[IPSET_ATTR_LINENO]);
 347
 348         ret = ip_set_get_ipaddr6(tb[IPSET_ATTR_IP], &ip);
 349         if (ret)
 350                 return ret;
 351
 352         ip6_netmask(&ip, h->netmask);
 353         if (ipv6_addr_any(&ip.in6))
 354                 return -IPSET_ERR_HASH_ELEM;
 355
 356         if (tb[IPSET_ATTR_TIMEOUT]) {
 357                 if (!with_timeout(h->timeout))
 358                         return -IPSET_ERR_TIMEOUT;
 359                 timeout = ip_set_timeout_uget(tb[IPSET_ATTR_TIMEOUT]);
 360         }
 361
 362         ret = adtfn(set, &ip, timeout, flags);
 363
 364         return ip_set_eexist(ret, flags) ? 0 : ret;
 365 }
 366
 367 /* Create hash:ip type of sets */
 368
 369 static int
 370 hash_ip_create(struct ip_set *set, struct nlattr *tb[], u32 flags)
 371 {
 372         u32 hashsize = IPSET_DEFAULT_HASHSIZE, maxelem = IPSET_DEFAULT_MAXELEM;
 373         u8 netmask, hbits;
 374         size_t hsize;
 375         struct ip_set_hash *h;
 376
 377         if (!(set->family == NFPROTO_IPV4 || set->family == NFPROTO_IPV6))
 378                 return -IPSET_ERR_INVALID_FAMILY;
 379         netmask = set->family == NFPROTO_IPV4 ? 32 : 128;
 380         pr_debug("Create set %s with family %s\n",
 381                  set->name, set->family == NFPROTO_IPV4 ? "inet" : "inet6");
 382
 383         if (unlikely(!ip_set_optattr_netorder(tb, IPSET_ATTR_HASHSIZE) ||
 384                      !ip_set_optattr_netorder(tb, IPSET_ATTR_MAXELEM) ||
 385                      !ip_set_optattr_netorder(tb, IPSET_ATTR_TIMEOUT)))
 386                 return -IPSET_ERR_PROTOCOL;
 387
 388         if (tb[IPSET_ATTR_HASHSIZE]) {
 389                 hashsize = ip_set_get_h32(tb[IPSET_ATTR_HASHSIZE]);
 390                 if (hashsize < IPSET_MIMINAL_HASHSIZE)
 391                         hashsize = IPSET_MIMINAL_HASHSIZE;
 392         }
 393
 394         if (tb[IPSET_ATTR_MAXELEM])
 395                 maxelem = ip_set_get_h32(tb[IPSET_ATTR_MAXELEM]);
 396
 397         if (tb[IPSET_ATTR_NETMASK]) {
 398                 netmask = nla_get_u8(tb[IPSET_ATTR_NETMASK]);
 399
 400                 if ((set->family == NFPROTO_IPV4 && netmask > 32) ||
 401                     (set->family == NFPROTO_IPV6 && netmask > 128) ||
 402                     netmask == 0)
 403                         return -IPSET_ERR_INVALID_NETMASK;
 404         }
 405
 406         h = kzalloc(sizeof(*h), GFP_KERNEL);
 407         if (!h)
 408                 return -ENOMEM;
 409
 410         h->maxelem = maxelem;
 411         h->netmask = netmask;
 412         get_random_bytes(&h->initval, sizeof(h->initval));
 413         h->timeout = IPSET_NO_TIMEOUT;
 414
 415         hbits = htable_bits(hashsize);
 416         hsize = htable_size(hbits);
 417         if (hsize == 0) {
 418                 kfree(h);
 419                 return -ENOMEM;
 420         }
 421         h->table = ip_set_alloc(hsize);
 422         if (!h->table) {
 423                 kfree(h);
 424                 return -ENOMEM;
 425         }
 426         h->table->htable_bits = hbits;
 427
 428         set->data = h;
 429
 430         if (tb[IPSET_ATTR_TIMEOUT]) {
 431                 h->timeout = ip_set_timeout_uget(tb[IPSET_ATTR_TIMEOUT]);
 432
 433                 set->variant = set->family == NFPROTO_IPV4
 434                         ? &hash_ip4_tvariant : &hash_ip6_tvariant;
 435
 436                 if (set->family == NFPROTO_IPV4)
 437                         hash_ip4_gc_init(set);
 438                 else
 439                         hash_ip6_gc_init(set);
 440         } else {
 441                 set->variant = set->family == NFPROTO_IPV4
 442                         ? &hash_ip4_variant : &hash_ip6_variant;
 443         }
 444
 445         pr_debug("create %s hashsize %u (%u) maxelem %u: %p(%p)\n",
 446                  set->name, jhash_size(h->table->htable_bits),
 447                  h->table->htable_bits, h->maxelem, set->data, h->table);
 448
 449         return 0;
 450 }
 451
 452 static struct ip_set_type hash_ip_type __read_mostly = {
 453         .name           = "hash:ip",
 454         .protocol       = IPSET_PROTOCOL,
 455         .features       = IPSET_TYPE_IP,
 456         .dimension      = IPSET_DIM_ONE,
 457         .family         = NFPROTO_UNSPEC,
 458         .revision_min   = REVISION_MIN,
 459         .revision_max   = REVISION_MAX,
 460         .create         = hash_ip_create,
 461         .create_policy  = {
 462                 [IPSET_ATTR_HASHSIZE]   = { .type = NLA_U32 },
 463                 [IPSET_ATTR_MAXELEM]    = { .type = NLA_U32 },
 464                 [IPSET_ATTR_PROBES]     = { .type = NLA_U8 },
 465                 [IPSET_ATTR_RESIZE]     = { .type = NLA_U8  },
 466                 [IPSET_ATTR_TIMEOUT]    = { .type = NLA_U32 },
 467                 [IPSET_ATTR_NETMASK]    = { .type = NLA_U8  },
 468         },
 469         .adt_policy     = {
 470                 [IPSET_ATTR_IP]         = { .type = NLA_NESTED },
 471                 [IPSET_ATTR_IP_TO]      = { .type = NLA_NESTED },
 472                 [IPSET_ATTR_CIDR]       = { .type = NLA_U8 },
 473                 [IPSET_ATTR_TIMEOUT]    = { .type = NLA_U32 },
 474                 [IPSET_ATTR_LINENO]     = { .type = NLA_U32 },
 475         },
 476         .me             = THIS_MODULE,
 477 };
 478
 479 static int __init
 480 hash_ip_init(void)
 481 {
 482         return ip_set_type_register(&hash_ip_type);
 483 }
 484
 485 static void __exit
 486 hash_ip_fini(void)
 487 {
 488         ip_set_type_unregister(&hash_ip_type);
 489 }
 490
 491 module_init(hash_ip_init);
 492 module_exit(hash_ip_fini);