net/netfilter/ipset/ip_set_bitmap_ip.c

   1 /* Copyright (C) 2000-2002 Joakim Axelsson <gozem@linux.nu>
   2  *                         Patrick Schaaf <bof@bof.de>
   3  * Copyright (C) 2003-2013 Jozsef Kadlecsik <kadlec@blackhole.kfki.hu>
   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
  10 /* Kernel module implementing an IP set type: the bitmap:ip type */
  11
  12 #include <linux/module.h>
  13 #include <linux/ip.h>
  14 #include <linux/skbuff.h>
  15 #include <linux/errno.h>
  16 #include <linux/bitops.h>
  17 #include <linux/spinlock.h>
  18 #include <linux/netlink.h>
  19 #include <linux/jiffies.h>
  20 #include <linux/timer.h>
  21 #include <net/netlink.h>
  22 #include <net/tcp.h>
  23
  24 #include <linux/netfilter/ipset/pfxlen.h>
  25 #include <linux/netfilter/ipset/ip_set.h>
  26 #include <linux/netfilter/ipset/ip_set_bitmap.h>
  27
  28 #define REVISION_MIN    0
  29 #define REVISION_MAX    1       /* Counter support added */
  30
  31 MODULE_LICENSE("GPL");
  32 MODULE_AUTHOR("Jozsef Kadlecsik <kadlec@blackhole.kfki.hu>");
  33 IP_SET_MODULE_DESC("bitmap:ip", REVISION_MIN, REVISION_MAX);
  34 MODULE_ALIAS("ip_set_bitmap:ip");
  35
  36 #define MTYPE           bitmap_ip
  37
  38 /* Type structure */
  39 struct bitmap_ip {
  40         void *members;          /* the set members */
  41         void *extensions;       /* data extensions */
  42         u32 first_ip;           /* host byte order, included in range */
  43         u32 last_ip;            /* host byte order, included in range */
  44         u32 elements;           /* number of max elements in the set */
  45         u32 hosts;              /* number of hosts in a subnet */
  46         size_t memsize;         /* members size */
  47         size_t dsize;           /* extensions struct size */
  48         size_t offset[IPSET_OFFSET_MAX]; /* Offsets to extensions */
  49         u8 netmask;             /* subnet netmask */
  50         u32 timeout;            /* timeout parameter */
  51         struct timer_list gc;   /* garbage collection */
  52 };
  53
  54 /* ADT structure for generic function args */
  55 struct bitmap_ip_adt_elem {
  56         u16 id;
  57 };
  58
  59 static inline u32
  60 ip_to_id(const struct bitmap_ip *m, u32 ip)
  61 {
  62         return ((ip & ip_set_hostmask(m->netmask)) - m->first_ip)/m->hosts;
  63 }
  64
  65 /* Common functions */
  66
  67 static inline int
  68 bitmap_ip_do_test(const struct bitmap_ip_adt_elem *e, struct bitmap_ip *map)
  69 {
  70         return !!test_bit(e->id, map->members);
  71 }
  72
  73 static inline int
  74 bitmap_ip_gc_test(u16 id, const struct bitmap_ip *map)
  75 {
  76         return !!test_bit(id, map->members);
  77 }
  78
  79 static inline int
  80 bitmap_ip_do_add(const struct bitmap_ip_adt_elem *e, struct bitmap_ip *map,
  81                  u32 flags)
  82 {
  83         return !!test_and_set_bit(e->id, map->members);
  84 }
  85
  86 static inline int
  87 bitmap_ip_do_del(const struct bitmap_ip_adt_elem *e, struct bitmap_ip *map)
  88 {
  89         return !test_and_clear_bit(e->id, map->members);
  90 }
  91
  92 static inline int
  93 bitmap_ip_do_list(struct sk_buff *skb, const struct bitmap_ip *map, u32 id)
  94 {
  95         return nla_put_ipaddr4(skb, IPSET_ATTR_IP,
  96                         htonl(map->first_ip + id * map->hosts));
  97 }
  98
  99 static inline int
 100 bitmap_ip_do_head(struct sk_buff *skb, const struct bitmap_ip *map)
 101 {
 102         return nla_put_ipaddr4(skb, IPSET_ATTR_IP, htonl(map->first_ip)) ||
 103                nla_put_ipaddr4(skb, IPSET_ATTR_IP_TO, htonl(map->last_ip)) ||
 104                (map->netmask != 32 &&
 105                 nla_put_u8(skb, IPSET_ATTR_NETMASK, map->netmask));
 106 }
 107
 108 static int
 109 bitmap_ip_kadt(struct ip_set *set, const struct sk_buff *skb,
 110                const struct xt_action_param *par,
 111                enum ipset_adt adt, struct ip_set_adt_opt *opt)
 112 {
 113         struct bitmap_ip *map = set->data;
 114         ipset_adtfn adtfn = set->variant->adt[adt];
 115         struct bitmap_ip_adt_elem e = { };
 116         struct ip_set_ext ext = IP_SET_INIT_KEXT(skb, opt, map);
 117         u32 ip;
 118
 119         ip = ntohl(ip4addr(skb, opt->flags & IPSET_DIM_ONE_SRC));
 120         if (ip < map->first_ip || ip > map->last_ip)
 121                 return -IPSET_ERR_BITMAP_RANGE;
 122
 123         e.id = ip_to_id(map, ip);
 124
 125         return adtfn(set, &e, &ext, &opt->ext, opt->cmdflags);
 126 }
 127
 128 static int
 129 bitmap_ip_uadt(struct ip_set *set, struct nlattr *tb[],
 130                enum ipset_adt adt, u32 *lineno, u32 flags, bool retried)
 131 {
 132         struct bitmap_ip *map = set->data;
 133         ipset_adtfn adtfn = set->variant->adt[adt];
 134         u32 ip, ip_to;
 135         struct bitmap_ip_adt_elem e = { };
 136         struct ip_set_ext ext = IP_SET_INIT_UEXT(map);
 137         int ret = 0;
 138
 139         if (unlikely(!tb[IPSET_ATTR_IP] ||
 140                      !ip_set_optattr_netorder(tb, IPSET_ATTR_TIMEOUT) ||
 141                      !ip_set_optattr_netorder(tb, IPSET_ATTR_PACKETS) ||
 142                      !ip_set_optattr_netorder(tb, IPSET_ATTR_BYTES)))
 143                 return -IPSET_ERR_PROTOCOL;
 144
 145         if (tb[IPSET_ATTR_LINENO])
 146                 *lineno = nla_get_u32(tb[IPSET_ATTR_LINENO]);
 147
 148         ret = ip_set_get_hostipaddr4(tb[IPSET_ATTR_IP], &ip) ||
 149               ip_set_get_extensions(set, tb, &ext);
 150         if (ret)
 151                 return ret;
 152
 153         if (ip < map->first_ip || ip > map->last_ip)
 154                 return -IPSET_ERR_BITMAP_RANGE;
 155
 156         if (adt == IPSET_TEST) {
 157                 e.id = ip_to_id(map, ip);
 158                 return adtfn(set, &e, &ext, &ext, flags);
 159         }
 160
 161         if (tb[IPSET_ATTR_IP_TO]) {
 162                 ret = ip_set_get_hostipaddr4(tb[IPSET_ATTR_IP_TO], &ip_to);
 163                 if (ret)
 164                         return ret;
 165                 if (ip > ip_to) {
 166                         swap(ip, ip_to);
 167                         if (ip < map->first_ip)
 168                                 return -IPSET_ERR_BITMAP_RANGE;
 169                 }
 170         } else if (tb[IPSET_ATTR_CIDR]) {
 171                 u8 cidr = nla_get_u8(tb[IPSET_ATTR_CIDR]);
 172
 173                 if (!cidr || cidr > 32)
 174                         return -IPSET_ERR_INVALID_CIDR;
 175                 ip_set_mask_from_to(ip, ip_to, cidr);
 176         } else
 177                 ip_to = ip;
 178
 179         if (ip_to > map->last_ip)
 180                 return -IPSET_ERR_BITMAP_RANGE;
 181
 182         for (; !before(ip_to, ip); ip += map->hosts) {
 183                 e.id = ip_to_id(map, ip);
 184                 ret = adtfn(set, &e, &ext, &ext, flags);
 185
 186                 if (ret && !ip_set_eexist(ret, flags))
 187                         return ret;
 188                 else
 189                         ret = 0;
 190         }
 191         return ret;
 192 }
 193
 194 static bool
 195 bitmap_ip_same_set(const struct ip_set *a, const struct ip_set *b)
 196 {
 197         const struct bitmap_ip *x = a->data;
 198         const struct bitmap_ip *y = b->data;
 199
 200         return x->first_ip == y->first_ip &&
 201                x->last_ip == y->last_ip &&
 202                x->netmask == y->netmask &&
 203                x->timeout == y->timeout &&
 204                a->extensions == b->extensions;
 205 }
 206
 207 /* Plain variant */
 208
 209 struct bitmap_ip_elem {
 210 };
 211
 212 /* Timeout variant */
 213
 214 struct bitmap_ipt_elem {
 215         unsigned long timeout;
 216 };
 217
 218 /* Plain variant with counter */
 219
 220 struct bitmap_ipc_elem {
 221         struct ip_set_counter counter;
 222 };
 223
 224 /* Timeout variant with counter */
 225
 226 struct bitmap_ipct_elem {
 227         unsigned long timeout;
 228         struct ip_set_counter counter;
 229 };
 230
 231 #include "ip_set_bitmap_gen.h"
 232
 233 /* Create bitmap:ip type of sets */
 234
 235 static bool
 236 init_map_ip(struct ip_set *set, struct bitmap_ip *map,
 237             u32 first_ip, u32 last_ip,
 238             u32 elements, u32 hosts, u8 netmask)
 239 {
 240         map->members = ip_set_alloc(map->memsize);
 241         if (!map->members)
 242                 return false;
 243         if (map->dsize) {
 244                 map->extensions = ip_set_alloc(map->dsize * elements);
 245                 if (!map->extensions) {
 246                         kfree(map->members);
 247                         return false;
 248                 }
 249         }
 250         map->first_ip = first_ip;
 251         map->last_ip = last_ip;
 252         map->elements = elements;
 253         map->hosts = hosts;
 254         map->netmask = netmask;
 255         map->timeout = IPSET_NO_TIMEOUT;
 256
 257         set->data = map;
 258         set->family = NFPROTO_IPV4;
 259
 260         return true;
 261 }
 262
 263 static int
 264 bitmap_ip_create(struct ip_set *set, struct nlattr *tb[], u32 flags)
 265 {
 266         struct bitmap_ip *map;
 267         u32 first_ip, last_ip, hosts, cadt_flags = 0;
 268         u64 elements;
 269         u8 netmask = 32;
 270         int ret;
 271
 272         if (unlikely(!tb[IPSET_ATTR_IP] ||
 273                      !ip_set_optattr_netorder(tb, IPSET_ATTR_TIMEOUT) ||
 274                      !ip_set_optattr_netorder(tb, IPSET_ATTR_CADT_FLAGS)))
 275                 return -IPSET_ERR_PROTOCOL;
 276
 277         ret = ip_set_get_hostipaddr4(tb[IPSET_ATTR_IP], &first_ip);
 278         if (ret)
 279                 return ret;
 280
 281         if (tb[IPSET_ATTR_IP_TO]) {
 282                 ret = ip_set_get_hostipaddr4(tb[IPSET_ATTR_IP_TO], &last_ip);
 283                 if (ret)
 284                         return ret;
 285                 if (first_ip > last_ip) {
 286                         u32 tmp = first_ip;
 287
 288                         first_ip = last_ip;
 289                         last_ip = tmp;
 290                 }
 291         } else if (tb[IPSET_ATTR_CIDR]) {
 292                 u8 cidr = nla_get_u8(tb[IPSET_ATTR_CIDR]);
 293
 294                 if (cidr >= 32)
 295                         return -IPSET_ERR_INVALID_CIDR;
 296                 ip_set_mask_from_to(first_ip, last_ip, cidr);
 297         } else
 298                 return -IPSET_ERR_PROTOCOL;
 299
 300         if (tb[IPSET_ATTR_NETMASK]) {
 301                 netmask = nla_get_u8(tb[IPSET_ATTR_NETMASK]);
 302
 303                 if (netmask > 32)
 304                         return -IPSET_ERR_INVALID_NETMASK;
 305
 306                 first_ip &= ip_set_hostmask(netmask);
 307                 last_ip |= ~ip_set_hostmask(netmask);
 308         }
 309
 310         if (netmask == 32) {
 311                 hosts = 1;
 312                 elements = (u64)last_ip - first_ip + 1;
 313         } else {
 314                 u8 mask_bits;
 315                 u32 mask;
 316
 317                 mask = range_to_mask(first_ip, last_ip, &mask_bits);
 318
 319                 if ((!mask && (first_ip || last_ip != 0xFFFFFFFF)) ||
 320                     netmask <= mask_bits)
 321                         return -IPSET_ERR_BITMAP_RANGE;
 322
 323                 pr_debug("mask_bits %u, netmask %u\n", mask_bits, netmask);
 324                 hosts = 2 << (32 - netmask - 1);
 325                 elements = 2 << (netmask - mask_bits - 1);
 326         }
 327         if (elements > IPSET_BITMAP_MAX_RANGE + 1)
 328                 return -IPSET_ERR_BITMAP_RANGE_SIZE;
 329
 330         pr_debug("hosts %u, elements %llu\n",
 331                  hosts, (unsigned long long)elements);
 332
 333         map = kzalloc(sizeof(*map), GFP_KERNEL);
 334         if (!map)
 335                 return -ENOMEM;
 336
 337         map->memsize = bitmap_bytes(0, elements - 1);
 338         set->variant = &bitmap_ip;
 339         if (tb[IPSET_ATTR_CADT_FLAGS])
 340                 cadt_flags = ip_set_get_h32(tb[IPSET_ATTR_CADT_FLAGS]);
 341         if (cadt_flags & IPSET_FLAG_WITH_COUNTERS) {
 342                 set->extensions |= IPSET_EXT_COUNTER;
 343                 if (tb[IPSET_ATTR_TIMEOUT]) {
 344                         map->dsize = sizeof(struct bitmap_ipct_elem);
 345                         map->offset[IPSET_OFFSET_TIMEOUT] =
 346                                 offsetof(struct bitmap_ipct_elem, timeout);
 347                         map->offset[IPSET_OFFSET_COUNTER] =
 348                                 offsetof(struct bitmap_ipct_elem, counter);
 349
 350                         if (!init_map_ip(set, map, first_ip, last_ip,
 351                                          elements, hosts, netmask)) {
 352                                 kfree(map);
 353                                 return -ENOMEM;
 354                         }
 355
 356                         map->timeout = ip_set_timeout_uget(
 357                                 tb[IPSET_ATTR_TIMEOUT]);
 358                         set->extensions |= IPSET_EXT_TIMEOUT;
 359
 360                         bitmap_ip_gc_init(set, bitmap_ip_gc);
 361                 } else {
 362                         map->dsize = sizeof(struct bitmap_ipc_elem);
 363                         map->offset[IPSET_OFFSET_COUNTER] =
 364                                 offsetof(struct bitmap_ipc_elem, counter);
 365
 366                         if (!init_map_ip(set, map, first_ip, last_ip,
 367                                          elements, hosts, netmask)) {
 368                                 kfree(map);
 369                                 return -ENOMEM;
 370                         }
 371                 }
 372         } else if (tb[IPSET_ATTR_TIMEOUT]) {
 373                 map->dsize = sizeof(struct bitmap_ipt_elem);
 374                 map->offset[IPSET_OFFSET_TIMEOUT] =
 375                         offsetof(struct bitmap_ipt_elem, timeout);
 376
 377                 if (!init_map_ip(set, map, first_ip, last_ip,
 378                                  elements, hosts, netmask)) {
 379                         kfree(map);
 380                         return -ENOMEM;
 381                 }
 382
 383                 map->timeout = ip_set_timeout_uget(tb[IPSET_ATTR_TIMEOUT]);
 384                 set->extensions |= IPSET_EXT_TIMEOUT;
 385
 386                 bitmap_ip_gc_init(set, bitmap_ip_gc);
 387         } else {
 388                 map->dsize = 0;
 389                 if (!init_map_ip(set, map, first_ip, last_ip,
 390                                  elements, hosts, netmask)) {
 391                         kfree(map);
 392                         return -ENOMEM;
 393                 }
 394         }
 395         return 0;
 396 }
 397
 398 static struct ip_set_type bitmap_ip_type __read_mostly = {
 399         .name           = "bitmap:ip",
 400         .protocol       = IPSET_PROTOCOL,
 401         .features       = IPSET_TYPE_IP,
 402         .dimension      = IPSET_DIM_ONE,
 403         .family         = NFPROTO_IPV4,
 404         .revision_min   = REVISION_MIN,
 405         .revision_max   = REVISION_MAX,
 406         .create         = bitmap_ip_create,
 407         .create_policy  = {
 408                 [IPSET_ATTR_IP]         = { .type = NLA_NESTED },
 409                 [IPSET_ATTR_IP_TO]      = { .type = NLA_NESTED },
 410                 [IPSET_ATTR_CIDR]       = { .type = NLA_U8 },
 411                 [IPSET_ATTR_NETMASK]    = { .type = NLA_U8  },
 412                 [IPSET_ATTR_TIMEOUT]    = { .type = NLA_U32 },
 413                 [IPSET_ATTR_CADT_FLAGS] = { .type = NLA_U32 },
 414         },
 415         .adt_policy     = {
 416                 [IPSET_ATTR_IP]         = { .type = NLA_NESTED },
 417                 [IPSET_ATTR_IP_TO]      = { .type = NLA_NESTED },
 418                 [IPSET_ATTR_CIDR]       = { .type = NLA_U8 },
 419                 [IPSET_ATTR_TIMEOUT]    = { .type = NLA_U32 },
 420                 [IPSET_ATTR_LINENO]     = { .type = NLA_U32 },
 421                 [IPSET_ATTR_BYTES]      = { .type = NLA_U64 },
 422                 [IPSET_ATTR_PACKETS]    = { .type = NLA_U64 },
 423         },
 424         .me             = THIS_MODULE,
 425 };
 426
 427 static int __init
 428 bitmap_ip_init(void)
 429 {
 430         return ip_set_type_register(&bitmap_ip_type);
 431 }
 432
 433 static void __exit
 434 bitmap_ip_fini(void)
 435 {
 436         ip_set_type_unregister(&bitmap_ip_type);
 437 }
 438
 439 module_init(bitmap_ip_init);
 440 module_exit(bitmap_ip_fini);