net/netfilter/ipset/ip_set_hash_net.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:net 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
  20 #include <linux/netfilter.h>
  21 #include <linux/netfilter/ipset/pfxlen.h>
  22 #include <linux/netfilter/ipset/ip_set.h>
  23 #include <linux/netfilter/ipset/ip_set_timeout.h>
  24 #include <linux/netfilter/ipset/ip_set_hash.h>
  25
  26 MODULE_LICENSE("GPL");
  27 MODULE_AUTHOR("Jozsef Kadlecsik <kadlec@blackhole.kfki.hu>");
  28 MODULE_DESCRIPTION("hash:net type of IP sets");
  29 MODULE_ALIAS("ip_set_hash:net");
  30
  31 /* Type specific function prefix */
  32 #define TYPE            hash_net
  33
  34 static bool
  35 hash_net_same_set(const struct ip_set *a, const struct ip_set *b);
  36
  37 #define hash_net4_same_set      hash_net_same_set
  38 #define hash_net6_same_set      hash_net_same_set
  39
  40 /* The type variant functions: IPv4 */
  41
  42 /* Member elements without timeout */
  43 struct hash_net4_elem {
  44         __be32 ip;
  45         u16 padding0;
  46         u8 padding1;
  47         u8 cidr;
  48 };
  49
  50 /* Member elements with timeout support */
  51 struct hash_net4_telem {
  52         __be32 ip;
  53         u16 padding0;
  54         u8 padding1;
  55         u8 cidr;
  56         unsigned long timeout;
  57 };
  58
  59 static inline bool
  60 hash_net4_data_equal(const struct hash_net4_elem *ip1,
  61                      const struct hash_net4_elem *ip2,
  62                      u32 *multi)
  63 {
  64         return ip1->ip == ip2->ip && ip1->cidr == ip2->cidr;
  65 }
  66
  67 static inline bool
  68 hash_net4_data_isnull(const struct hash_net4_elem *elem)
  69 {
  70         return elem->cidr == 0;
  71 }
  72
  73 static inline void
  74 hash_net4_data_copy(struct hash_net4_elem *dst,
  75                     const struct hash_net4_elem *src)
  76 {
  77         dst->ip = src->ip;
  78         dst->cidr = src->cidr;
  79 }
  80
  81 static inline void
  82 hash_net4_data_netmask(struct hash_net4_elem *elem, u8 cidr)
  83 {
  84         elem->ip &= ip_set_netmask(cidr);
  85         elem->cidr = cidr;
  86 }
  87
  88 /* Zero CIDR values cannot be stored */
  89 static inline void
  90 hash_net4_data_zero_out(struct hash_net4_elem *elem)
  91 {
  92         elem->cidr = 0;
  93 }
  94
  95 static bool
  96 hash_net4_data_list(struct sk_buff *skb, const struct hash_net4_elem *data)
  97 {
  98         NLA_PUT_IPADDR4(skb, IPSET_ATTR_IP, data->ip);
  99         NLA_PUT_U8(skb, IPSET_ATTR_CIDR, data->cidr);
 100         return 0;
 101
 102 nla_put_failure:
 103         return 1;
 104 }
 105
 106 static bool
 107 hash_net4_data_tlist(struct sk_buff *skb, const struct hash_net4_elem *data)
 108 {
 109         const struct hash_net4_telem *tdata =
 110                 (const struct hash_net4_telem *)data;
 111
 112         NLA_PUT_IPADDR4(skb, IPSET_ATTR_IP, tdata->ip);
 113         NLA_PUT_U8(skb, IPSET_ATTR_CIDR, tdata->cidr);
 114         NLA_PUT_NET32(skb, IPSET_ATTR_TIMEOUT,
 115                       htonl(ip_set_timeout_get(tdata->timeout)));
 116
 117         return 0;
 118
 119 nla_put_failure:
 120         return 1;
 121 }
 122
 123 #define IP_SET_HASH_WITH_NETS
 124
 125 #define PF              4
 126 #define HOST_MASK       32
 127 #include <linux/netfilter/ipset/ip_set_ahash.h>
 128
 129 static inline void
 130 hash_net4_data_next(struct ip_set_hash *h,
 131                     const struct hash_net4_elem *d)
 132 {
 133         h->next.ip = ntohl(d->ip);
 134 }
 135
 136 static int
 137 hash_net4_kadt(struct ip_set *set, const struct sk_buff *skb,
 138                const struct xt_action_param *par,
 139                enum ipset_adt adt, const struct ip_set_adt_opt *opt)
 140 {
 141         const struct ip_set_hash *h = set->data;
 142         ipset_adtfn adtfn = set->variant->adt[adt];
 143         struct hash_net4_elem data = {
 144                 .cidr = h->nets[0].cidr ? h->nets[0].cidr : HOST_MASK
 145         };
 146
 147         if (data.cidr == 0)
 148                 return -EINVAL;
 149         if (adt == IPSET_TEST)
 150                 data.cidr = HOST_MASK;
 151
 152         ip4addrptr(skb, opt->flags & IPSET_DIM_ONE_SRC, &data.ip);
 153         data.ip &= ip_set_netmask(data.cidr);
 154
 155         return adtfn(set, &data, opt_timeout(opt, h), opt->cmdflags);
 156 }
 157
 158 static int
 159 hash_net4_uadt(struct ip_set *set, struct nlattr *tb[],
 160                enum ipset_adt adt, u32 *lineno, u32 flags, bool retried)
 161 {
 162         const struct ip_set_hash *h = set->data;
 163         ipset_adtfn adtfn = set->variant->adt[adt];
 164         struct hash_net4_elem data = { .cidr = HOST_MASK };
 165         u32 timeout = h->timeout;
 166         u32 ip = 0, ip_to, last;
 167         int ret;
 168
 169         if (unlikely(!tb[IPSET_ATTR_IP] ||
 170                      !ip_set_optattr_netorder(tb, IPSET_ATTR_TIMEOUT)))
 171                 return -IPSET_ERR_PROTOCOL;
 172
 173         if (tb[IPSET_ATTR_LINENO])
 174                 *lineno = nla_get_u32(tb[IPSET_ATTR_LINENO]);
 175
 176         ret = ip_set_get_hostipaddr4(tb[IPSET_ATTR_IP], &ip);
 177         if (ret)
 178                 return ret;
 179
 180         if (tb[IPSET_ATTR_CIDR]) {
 181                 data.cidr = nla_get_u8(tb[IPSET_ATTR_CIDR]);
 182                 if (!data.cidr)
 183                         return -IPSET_ERR_INVALID_CIDR;
 184         }
 185
 186         if (tb[IPSET_ATTR_TIMEOUT]) {
 187                 if (!with_timeout(h->timeout))
 188                         return -IPSET_ERR_TIMEOUT;
 189                 timeout = ip_set_timeout_uget(tb[IPSET_ATTR_TIMEOUT]);
 190         }
 191
 192         if (adt == IPSET_TEST || !tb[IPSET_ATTR_IP_TO]) {
 193                 data.ip = htonl(ip & ip_set_hostmask(data.cidr));
 194                 ret = adtfn(set, &data, timeout, flags);
 195                 return ip_set_eexist(ret, flags) ? 0 : ret;
 196         }
 197
 198         ip_to = ip;
 199         if (tb[IPSET_ATTR_IP_TO]) {
 200                 ret = ip_set_get_hostipaddr4(tb[IPSET_ATTR_IP_TO], &ip_to);
 201                 if (ret)
 202                         return ret;
 203                 if (ip_to < ip)
 204                         swap(ip, ip_to);
 205                 if (ip + UINT_MAX == ip_to)
 206                         return -IPSET_ERR_HASH_RANGE;
 207         }
 208         if (retried)
 209                 ip = h->next.ip;
 210         while (!after(ip, ip_to)) {
 211                 data.ip = htonl(ip);
 212                 last = ip_set_range_to_cidr(ip, ip_to, &data.cidr);
 213                 ret = adtfn(set, &data, timeout, flags);
 214                 if (ret && !ip_set_eexist(ret, flags))
 215                         return ret;
 216                 else
 217                         ret = 0;
 218                 ip = last + 1;
 219         }
 220         return ret;
 221 }
 222
 223 static bool
 224 hash_net_same_set(const struct ip_set *a, const struct ip_set *b)
 225 {
 226         const struct ip_set_hash *x = a->data;
 227         const struct ip_set_hash *y = b->data;
 228
 229         /* Resizing changes htable_bits, so we ignore it */
 230         return x->maxelem == y->maxelem &&
 231                x->timeout == y->timeout;
 232 }
 233
 234 /* The type variant functions: IPv6 */
 235
 236 struct hash_net6_elem {
 237         union nf_inet_addr ip;
 238         u16 padding0;
 239         u8 padding1;
 240         u8 cidr;
 241 };
 242
 243 struct hash_net6_telem {
 244         union nf_inet_addr ip;
 245         u16 padding0;
 246         u8 padding1;
 247         u8 cidr;
 248         unsigned long timeout;
 249 };
 250
 251 static inline bool
 252 hash_net6_data_equal(const struct hash_net6_elem *ip1,
 253                      const struct hash_net6_elem *ip2,
 254                      u32 *multi)
 255 {
 256         return ipv6_addr_cmp(&ip1->ip.in6, &ip2->ip.in6) == 0 &&
 257                ip1->cidr == ip2->cidr;
 258 }
 259
 260 static inline bool
 261 hash_net6_data_isnull(const struct hash_net6_elem *elem)
 262 {
 263         return elem->cidr == 0;
 264 }
 265
 266 static inline void
 267 hash_net6_data_copy(struct hash_net6_elem *dst,
 268                     const struct hash_net6_elem *src)
 269 {
 270         dst->ip.in6 = src->ip.in6;
 271         dst->cidr = src->cidr;
 272 }
 273
 274 static inline void
 275 hash_net6_data_zero_out(struct hash_net6_elem *elem)
 276 {
 277         elem->cidr = 0;
 278 }
 279
 280 static inline void
 281 ip6_netmask(union nf_inet_addr *ip, u8 prefix)
 282 {
 283         ip->ip6[0] &= ip_set_netmask6(prefix)[0];
 284         ip->ip6[1] &= ip_set_netmask6(prefix)[1];
 285         ip->ip6[2] &= ip_set_netmask6(prefix)[2];
 286         ip->ip6[3] &= ip_set_netmask6(prefix)[3];
 287 }
 288
 289 static inline void
 290 hash_net6_data_netmask(struct hash_net6_elem *elem, u8 cidr)
 291 {
 292         ip6_netmask(&elem->ip, cidr);
 293         elem->cidr = cidr;
 294 }
 295
 296 static bool
 297 hash_net6_data_list(struct sk_buff *skb, const struct hash_net6_elem *data)
 298 {
 299         NLA_PUT_IPADDR6(skb, IPSET_ATTR_IP, &data->ip);
 300         NLA_PUT_U8(skb, IPSET_ATTR_CIDR, data->cidr);
 301         return 0;
 302
 303 nla_put_failure:
 304         return 1;
 305 }
 306
 307 static bool
 308 hash_net6_data_tlist(struct sk_buff *skb, const struct hash_net6_elem *data)
 309 {
 310         const struct hash_net6_telem *e =
 311                 (const struct hash_net6_telem *)data;
 312
 313         NLA_PUT_IPADDR6(skb, IPSET_ATTR_IP, &e->ip);
 314         NLA_PUT_U8(skb, IPSET_ATTR_CIDR, e->cidr);
 315         NLA_PUT_NET32(skb, IPSET_ATTR_TIMEOUT,
 316                       htonl(ip_set_timeout_get(e->timeout)));
 317         return 0;
 318
 319 nla_put_failure:
 320         return 1;
 321 }
 322
 323 #undef PF
 324 #undef HOST_MASK
 325
 326 #define PF              6
 327 #define HOST_MASK       128
 328 #include <linux/netfilter/ipset/ip_set_ahash.h>
 329
 330 static inline void
 331 hash_net6_data_next(struct ip_set_hash *h,
 332                     const struct hash_net6_elem *d)
 333 {
 334 }
 335
 336 static int
 337 hash_net6_kadt(struct ip_set *set, const struct sk_buff *skb,
 338                const struct xt_action_param *par,
 339                enum ipset_adt adt, const struct ip_set_adt_opt *opt)
 340 {
 341         const struct ip_set_hash *h = set->data;
 342         ipset_adtfn adtfn = set->variant->adt[adt];
 343         struct hash_net6_elem data = {
 344                 .cidr = h->nets[0].cidr ? h->nets[0].cidr : HOST_MASK
 345         };
 346
 347         if (data.cidr == 0)
 348                 return -EINVAL;
 349         if (adt == IPSET_TEST)
 350                 data.cidr = HOST_MASK;
 351
 352         ip6addrptr(skb, opt->flags & IPSET_DIM_ONE_SRC, &data.ip.in6);
 353         ip6_netmask(&data.ip, data.cidr);
 354
 355         return adtfn(set, &data, opt_timeout(opt, h), opt->cmdflags);
 356 }
 357
 358 static int
 359 hash_net6_uadt(struct ip_set *set, struct nlattr *tb[],
 360                enum ipset_adt adt, u32 *lineno, u32 flags, bool retried)
 361 {
 362         const struct ip_set_hash *h = set->data;
 363         ipset_adtfn adtfn = set->variant->adt[adt];
 364         struct hash_net6_elem data = { .cidr = HOST_MASK };
 365         u32 timeout = h->timeout;
 366         int ret;
 367
 368         if (unlikely(!tb[IPSET_ATTR_IP] ||
 369                      !ip_set_optattr_netorder(tb, IPSET_ATTR_TIMEOUT)))
 370                 return -IPSET_ERR_PROTOCOL;
 371         if (unlikely(tb[IPSET_ATTR_IP_TO]))
 372                 return -IPSET_ERR_HASH_RANGE_UNSUPPORTED;
 373
 374         if (tb[IPSET_ATTR_LINENO])
 375                 *lineno = nla_get_u32(tb[IPSET_ATTR_LINENO]);
 376
 377         ret = ip_set_get_ipaddr6(tb[IPSET_ATTR_IP], &data.ip);
 378         if (ret)
 379                 return ret;
 380
 381         if (tb[IPSET_ATTR_CIDR])
 382                 data.cidr = nla_get_u8(tb[IPSET_ATTR_CIDR]);
 383
 384         if (!data.cidr)
 385                 return -IPSET_ERR_INVALID_CIDR;
 386
 387         ip6_netmask(&data.ip, data.cidr);
 388
 389         if (tb[IPSET_ATTR_TIMEOUT]) {
 390                 if (!with_timeout(h->timeout))
 391                         return -IPSET_ERR_TIMEOUT;
 392                 timeout = ip_set_timeout_uget(tb[IPSET_ATTR_TIMEOUT]);
 393         }
 394
 395         ret = adtfn(set, &data, timeout, flags);
 396
 397         return ip_set_eexist(ret, flags) ? 0 : ret;
 398 }
 399
 400 /* Create hash:ip type of sets */
 401
 402 static int
 403 hash_net_create(struct ip_set *set, struct nlattr *tb[], u32 flags)
 404 {
 405         u32 hashsize = IPSET_DEFAULT_HASHSIZE, maxelem = IPSET_DEFAULT_MAXELEM;
 406         struct ip_set_hash *h;
 407         u8 hbits;
 408
 409         if (!(set->family == AF_INET || set->family == AF_INET6))
 410                 return -IPSET_ERR_INVALID_FAMILY;
 411
 412         if (unlikely(!ip_set_optattr_netorder(tb, IPSET_ATTR_HASHSIZE) ||
 413                      !ip_set_optattr_netorder(tb, IPSET_ATTR_MAXELEM) ||
 414                      !ip_set_optattr_netorder(tb, IPSET_ATTR_TIMEOUT)))
 415                 return -IPSET_ERR_PROTOCOL;
 416
 417         if (tb[IPSET_ATTR_HASHSIZE]) {
 418                 hashsize = ip_set_get_h32(tb[IPSET_ATTR_HASHSIZE]);
 419                 if (hashsize < IPSET_MIMINAL_HASHSIZE)
 420                         hashsize = IPSET_MIMINAL_HASHSIZE;
 421         }
 422
 423         if (tb[IPSET_ATTR_MAXELEM])
 424                 maxelem = ip_set_get_h32(tb[IPSET_ATTR_MAXELEM]);
 425
 426         h = kzalloc(sizeof(*h)
 427                     + sizeof(struct ip_set_hash_nets)
 428                       * (set->family == AF_INET ? 32 : 128), GFP_KERNEL);
 429         if (!h)
 430                 return -ENOMEM;
 431
 432         h->maxelem = maxelem;
 433         get_random_bytes(&h->initval, sizeof(h->initval));
 434         h->timeout = IPSET_NO_TIMEOUT;
 435
 436         hbits = htable_bits(hashsize);
 437         h->table = ip_set_alloc(
 438                         sizeof(struct htable)
 439                         + jhash_size(hbits) * sizeof(struct hbucket));
 440         if (!h->table) {
 441                 kfree(h);
 442                 return -ENOMEM;
 443         }
 444         h->table->htable_bits = hbits;
 445
 446         set->data = h;
 447
 448         if (tb[IPSET_ATTR_TIMEOUT]) {
 449                 h->timeout = ip_set_timeout_uget(tb[IPSET_ATTR_TIMEOUT]);
 450
 451                 set->variant = set->family == AF_INET
 452                         ? &hash_net4_tvariant : &hash_net6_tvariant;
 453
 454                 if (set->family == AF_INET)
 455                         hash_net4_gc_init(set);
 456                 else
 457                         hash_net6_gc_init(set);
 458         } else {
 459                 set->variant = set->family == AF_INET
 460                         ? &hash_net4_variant : &hash_net6_variant;
 461         }
 462
 463         pr_debug("create %s hashsize %u (%u) maxelem %u: %p(%p)\n",
 464                  set->name, jhash_size(h->table->htable_bits),
 465                  h->table->htable_bits, h->maxelem, set->data, h->table);
 466
 467         return 0;
 468 }
 469
 470 static struct ip_set_type hash_net_type __read_mostly = {
 471         .name           = "hash:net",
 472         .protocol       = IPSET_PROTOCOL,
 473         .features       = IPSET_TYPE_IP,
 474         .dimension      = IPSET_DIM_ONE,
 475         .family         = AF_UNSPEC,
 476         .revision_min   = 0,
 477         .revision_max   = 1,    /* Range as input support for IPv4 added */
 478         .create         = hash_net_create,
 479         .create_policy  = {
 480                 [IPSET_ATTR_HASHSIZE]   = { .type = NLA_U32 },
 481                 [IPSET_ATTR_MAXELEM]    = { .type = NLA_U32 },
 482                 [IPSET_ATTR_PROBES]     = { .type = NLA_U8 },
 483                 [IPSET_ATTR_RESIZE]     = { .type = NLA_U8  },
 484                 [IPSET_ATTR_TIMEOUT]    = { .type = NLA_U32 },
 485         },
 486         .adt_policy     = {
 487                 [IPSET_ATTR_IP]         = { .type = NLA_NESTED },
 488                 [IPSET_ATTR_IP_TO]      = { .type = NLA_NESTED },
 489                 [IPSET_ATTR_CIDR]       = { .type = NLA_U8 },
 490                 [IPSET_ATTR_TIMEOUT]    = { .type = NLA_U32 },
 491         },
 492         .me             = THIS_MODULE,
 493 };
 494
 495 static int __init
 496 hash_net_init(void)
 497 {
 498         return ip_set_type_register(&hash_net_type);
 499 }
 500
 501 static void __exit
 502 hash_net_fini(void)
 503 {
 504         ip_set_type_unregister(&hash_net_type);
 505 }
 506
 507 module_init(hash_net_init);
 508 module_exit(hash_net_fini);