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 IPSET_TYPE_REV_MIN      0
  29 /*                              1          Counter support added */
  30 /*                              2          Comment support added */
  31 #define IPSET_TYPE_REV_MAX      3       /* skbinfo support added */
  32
  33 MODULE_LICENSE("GPL");
  34 MODULE_AUTHOR("Jozsef Kadlecsik <kadlec@blackhole.kfki.hu>");
  35 IP_SET_MODULE_DESC("bitmap:ip", IPSET_TYPE_REV_MIN, IPSET_TYPE_REV_MAX);
  36 MODULE_ALIAS("ip_set_bitmap:ip");
  37
  38 #define MTYPE           bitmap_ip
  39 #define HOST_MASK       32
  40
  41 /* Type structure */
  42 struct bitmap_ip {
  43         void *members;          /* the set members */
  44         u32 first_ip;           /* host byte order, included in range */
  45         u32 last_ip;            /* host byte order, included in range */
  46         u32 elements;           /* number of max elements in the set */
  47         u32 hosts;              /* number of hosts in a subnet */
  48         size_t memsize;         /* members size */
  49         u8 netmask;             /* subnet netmask */
  50         struct timer_list gc;   /* garbage collection */
  51         struct ip_set *set;     /* attached to this ip_set */
  52         unsigned char extensions[0]     /* data extensions */
  53                 __aligned(__alignof__(u64));
  54 };
  55
  56 /* ADT structure for generic function args */
  57 struct bitmap_ip_adt_elem {
  58         u16 id;
  59 };
  60
  61 static inline u32
  62 ip_to_id(const struct bitmap_ip *m, u32 ip)
  63 {
  64         return ((ip & ip_set_hostmask(m->netmask)) - m->first_ip) / m->hosts;
  65 }
  66
  67 /* Common functions */
  68
  69 static inline int
  70 bitmap_ip_do_test(const struct bitmap_ip_adt_elem *e,
  71                   struct bitmap_ip *map, size_t dsize)
  72 {
  73         return !!test_bit(e->id, map->members);
  74 }
  75
  76 static inline int
  77 bitmap_ip_gc_test(u16 id, const struct bitmap_ip *map, size_t dsize)
  78 {
  79         return !!test_bit(id, map->members);
  80 }
  81
  82 static inline int
  83 bitmap_ip_do_add(const struct bitmap_ip_adt_elem *e, struct bitmap_ip *map,
  84                  u32 flags, size_t dsize)
  85 {
  86         return !!test_bit(e->id, map->members);
  87 }
  88
  89 static inline int
  90 bitmap_ip_do_del(const struct bitmap_ip_adt_elem *e, struct bitmap_ip *map)
  91 {
  92         return !test_and_clear_bit(e->id, map->members);
  93 }
  94
  95 static inline int
  96 bitmap_ip_do_list(struct sk_buff *skb, const struct bitmap_ip *map, u32 id,
  97                   size_t dsize)
  98 {
  99         return nla_put_ipaddr4(skb, IPSET_ATTR_IP,
 100                         htonl(map->first_ip + id * map->hosts));
 101 }
 102
 103 static inline int
 104 bitmap_ip_do_head(struct sk_buff *skb, const struct bitmap_ip *map)
 105 {
 106         return nla_put_ipaddr4(skb, IPSET_ATTR_IP, htonl(map->first_ip)) ||
 107                nla_put_ipaddr4(skb, IPSET_ATTR_IP_TO, htonl(map->last_ip)) ||
 108                (map->netmask != 32 &&
 109                 nla_put_u8(skb, IPSET_ATTR_NETMASK, map->netmask));
 110 }
 111
 112 static int
 113 bitmap_ip_kadt(struct ip_set *set, const struct sk_buff *skb,
 114                const struct xt_action_param *par,
 115                enum ipset_adt adt, struct ip_set_adt_opt *opt)
 116 {
 117         struct bitmap_ip *map = set->data;
 118         ipset_adtfn adtfn = set->variant->adt[adt];
 119         struct bitmap_ip_adt_elem e = { .id = 0 };
 120         struct ip_set_ext ext = IP_SET_INIT_KEXT(skb, opt, set);
 121         u32 ip;
 122
 123         ip = ntohl(ip4addr(skb, opt->flags & IPSET_DIM_ONE_SRC));
 124         if (ip < map->first_ip || ip > map->last_ip)
 125                 return -IPSET_ERR_BITMAP_RANGE;
 126
 127         e.id = ip_to_id(map, ip);
 128
 129         return adtfn(set, &e, &ext, &opt->ext, opt->cmdflags);
 130 }
 131
 132 static int
 133 bitmap_ip_uadt(struct ip_set *set, struct nlattr *tb[],
 134                enum ipset_adt adt, u32 *lineno, u32 flags, bool retried)
 135 {
 136         struct bitmap_ip *map = set->data;
 137         ipset_adtfn adtfn = set->variant->adt[adt];
 138         u32 ip = 0, ip_to = 0;
 139         struct bitmap_ip_adt_elem e = { .id = 0 };
 140         struct ip_set_ext ext = IP_SET_INIT_UEXT(set);
 141         int ret = 0;
 142
 143         if (tb[IPSET_ATTR_LINENO])
 144                 *lineno = nla_get_u32(tb[IPSET_ATTR_LINENO]);
 145
 146         if (unlikely(!tb[IPSET_ATTR_IP]))
 147                 return -IPSET_ERR_PROTOCOL;
 148
 149         ret = ip_set_get_hostipaddr4(tb[IPSET_ATTR_IP], &ip);
 150         if (ret)
 151                 return ret;
 152
 153         ret = ip_set_get_extensions(set, tb, &ext);
 154         if (ret)
 155                 return ret;
 156
 157         if (ip < map->first_ip || ip > map->last_ip)
 158                 return -IPSET_ERR_BITMAP_RANGE;
 159
 160         if (adt == IPSET_TEST) {
 161                 e.id = ip_to_id(map, ip);
 162                 return adtfn(set, &e, &ext, &ext, flags);
 163         }
 164
 165         if (tb[IPSET_ATTR_IP_TO]) {
 166                 ret = ip_set_get_hostipaddr4(tb[IPSET_ATTR_IP_TO], &ip_to);
 167                 if (ret)
 168                         return ret;
 169                 if (ip > ip_to) {
 170                         swap(ip, ip_to);
 171                         if (ip < map->first_ip)
 172                                 return -IPSET_ERR_BITMAP_RANGE;
 173                 }
 174         } else if (tb[IPSET_ATTR_CIDR]) {
 175                 u8 cidr = nla_get_u8(tb[IPSET_ATTR_CIDR]);
 176
 177                 if (!cidr || cidr > HOST_MASK)
 178                         return -IPSET_ERR_INVALID_CIDR;
 179                 ip_set_mask_from_to(ip, ip_to, cidr);
 180         } else {
 181                 ip_to = ip;
 182         }
 183
 184         if (ip_to > map->last_ip)
 185                 return -IPSET_ERR_BITMAP_RANGE;
 186
 187         for (; !before(ip_to, ip); ip += map->hosts) {
 188                 e.id = ip_to_id(map, ip);
 189                 ret = adtfn(set, &e, &ext, &ext, flags);
 190
 191                 if (ret && !ip_set_eexist(ret, flags))
 192                         return ret;
 193
 194                 ret = 0;
 195         }
 196         return ret;
 197 }
 198
 199 static bool
 200 bitmap_ip_same_set(const struct ip_set *a, const struct ip_set *b)
 201 {
 202         const struct bitmap_ip *x = a->data;
 203         const struct bitmap_ip *y = b->data;
 204
 205         return x->first_ip == y->first_ip &&
 206                x->last_ip == y->last_ip &&
 207                x->netmask == y->netmask &&
 208                a->timeout == b->timeout &&
 209                a->extensions == b->extensions;
 210 }
 211
 212 /* Plain variant */
 213
 214 struct bitmap_ip_elem {
 215 };
 216
 217 #include "ip_set_bitmap_gen.h"
 218
 219 /* Create bitmap:ip type of sets */
 220
 221 static bool
 222 init_map_ip(struct ip_set *set, struct bitmap_ip *map,
 223             u32 first_ip, u32 last_ip,
 224             u32 elements, u32 hosts, u8 netmask)
 225 {
 226         map->members = ip_set_alloc(map->memsize);
 227         if (!map->members)
 228                 return false;
 229         map->first_ip = first_ip;
 230         map->last_ip = last_ip;
 231         map->elements = elements;
 232         map->hosts = hosts;
 233         map->netmask = netmask;
 234         set->timeout = IPSET_NO_TIMEOUT;
 235
 236         map->set = set;
 237         set->data = map;
 238         set->family = NFPROTO_IPV4;
 239
 240         return true;
 241 }
 242
 243 static int
 244 bitmap_ip_create(struct net *net, struct ip_set *set, struct nlattr *tb[],
 245                  u32 flags)
 246 {
 247         struct bitmap_ip *map;
 248         u32 first_ip = 0, last_ip = 0, hosts;
 249         u64 elements;
 250         u8 netmask = 32;
 251         int ret;
 252
 253         if (unlikely(!tb[IPSET_ATTR_IP] ||
 254                      !ip_set_optattr_netorder(tb, IPSET_ATTR_TIMEOUT) ||
 255                      !ip_set_optattr_netorder(tb, IPSET_ATTR_CADT_FLAGS)))
 256                 return -IPSET_ERR_PROTOCOL;
 257
 258         ret = ip_set_get_hostipaddr4(tb[IPSET_ATTR_IP], &first_ip);
 259         if (ret)
 260                 return ret;
 261
 262         if (tb[IPSET_ATTR_IP_TO]) {
 263                 ret = ip_set_get_hostipaddr4(tb[IPSET_ATTR_IP_TO], &last_ip);
 264                 if (ret)
 265                         return ret;
 266                 if (first_ip > last_ip) {
 267                         u32 tmp = first_ip;
 268
 269                         first_ip = last_ip;
 270                         last_ip = tmp;
 271                 }
 272         } else if (tb[IPSET_ATTR_CIDR]) {
 273                 u8 cidr = nla_get_u8(tb[IPSET_ATTR_CIDR]);
 274
 275                 if (cidr >= HOST_MASK)
 276                         return -IPSET_ERR_INVALID_CIDR;
 277                 ip_set_mask_from_to(first_ip, last_ip, cidr);
 278         } else {
 279                 return -IPSET_ERR_PROTOCOL;
 280         }
 281
 282         if (tb[IPSET_ATTR_NETMASK]) {
 283                 netmask = nla_get_u8(tb[IPSET_ATTR_NETMASK]);
 284
 285                 if (netmask > HOST_MASK)
 286                         return -IPSET_ERR_INVALID_NETMASK;
 287
 288                 first_ip &= ip_set_hostmask(netmask);
 289                 last_ip |= ~ip_set_hostmask(netmask);
 290         }
 291
 292         if (netmask == 32) {
 293                 hosts = 1;
 294                 elements = (u64)last_ip - first_ip + 1;
 295         } else {
 296                 u8 mask_bits;
 297                 u32 mask;
 298
 299                 mask = range_to_mask(first_ip, last_ip, &mask_bits);
 300
 301                 if ((!mask && (first_ip || last_ip != 0xFFFFFFFF)) ||
 302                     netmask <= mask_bits)
 303                         return -IPSET_ERR_BITMAP_RANGE;
 304
 305                 pr_debug("mask_bits %u, netmask %u\n", mask_bits, netmask);
 306                 hosts = 2 << (32 - netmask - 1);
 307                 elements = 2 << (netmask - mask_bits - 1);
 308         }
 309         if (elements > IPSET_BITMAP_MAX_RANGE + 1)
 310                 return -IPSET_ERR_BITMAP_RANGE_SIZE;
 311
 312         pr_debug("hosts %u, elements %llu\n",
 313                  hosts, (unsigned long long)elements);
 314
 315         set->dsize = ip_set_elem_len(set, tb, 0, 0);
 316         map = ip_set_alloc(sizeof(*map) + elements * set->dsize);
 317         if (!map)
 318                 return -ENOMEM;
 319
 320         map->memsize = bitmap_bytes(0, elements - 1);
 321         set->variant = &bitmap_ip;
 322         if (!init_map_ip(set, map, first_ip, last_ip,
 323                          elements, hosts, netmask)) {
 324                 kfree(map);
 325                 return -ENOMEM;
 326         }
 327         if (tb[IPSET_ATTR_TIMEOUT]) {
 328                 set->timeout = ip_set_timeout_uget(tb[IPSET_ATTR_TIMEOUT]);
 329                 bitmap_ip_gc_init(set, bitmap_ip_gc);
 330         }
 331         return 0;
 332 }
 333
 334 static struct ip_set_type bitmap_ip_type __read_mostly = {
 335         .name           = "bitmap:ip",
 336         .protocol       = IPSET_PROTOCOL,
 337         .features       = IPSET_TYPE_IP,
 338         .dimension      = IPSET_DIM_ONE,
 339         .family         = NFPROTO_IPV4,
 340         .revision_min   = IPSET_TYPE_REV_MIN,
 341         .revision_max   = IPSET_TYPE_REV_MAX,
 342         .create         = bitmap_ip_create,
 343         .create_policy  = {
 344                 [IPSET_ATTR_IP]         = { .type = NLA_NESTED },
 345                 [IPSET_ATTR_IP_TO]      = { .type = NLA_NESTED },
 346                 [IPSET_ATTR_CIDR]       = { .type = NLA_U8 },
 347                 [IPSET_ATTR_NETMASK]    = { .type = NLA_U8  },
 348                 [IPSET_ATTR_TIMEOUT]    = { .type = NLA_U32 },
 349                 [IPSET_ATTR_CADT_FLAGS] = { .type = NLA_U32 },
 350         },
 351         .adt_policy     = {
 352                 [IPSET_ATTR_IP]         = { .type = NLA_NESTED },
 353                 [IPSET_ATTR_IP_TO]      = { .type = NLA_NESTED },
 354                 [IPSET_ATTR_CIDR]       = { .type = NLA_U8 },
 355                 [IPSET_ATTR_TIMEOUT]    = { .type = NLA_U32 },
 356                 [IPSET_ATTR_LINENO]     = { .type = NLA_U32 },
 357                 [IPSET_ATTR_BYTES]      = { .type = NLA_U64 },
 358                 [IPSET_ATTR_PACKETS]    = { .type = NLA_U64 },
 359                 [IPSET_ATTR_COMMENT]    = { .type = NLA_NUL_STRING,
 360                                             .len  = IPSET_MAX_COMMENT_SIZE },
 361                 [IPSET_ATTR_SKBMARK]    = { .type = NLA_U64 },
 362                 [IPSET_ATTR_SKBPRIO]    = { .type = NLA_U32 },
 363                 [IPSET_ATTR_SKBQUEUE]   = { .type = NLA_U16 },
 364         },
 365         .me             = THIS_MODULE,
 366 };
 367
 368 static int __init
 369 bitmap_ip_init(void)
 370 {
 371         return ip_set_type_register(&bitmap_ip_type);
 372 }
 373
 374 static void __exit
 375 bitmap_ip_fini(void)
 376 {
 377         rcu_barrier();
 378         ip_set_type_unregister(&bitmap_ip_type);
 379 }
 380
 381 module_init(bitmap_ip_init);
 382 module_exit(bitmap_ip_fini);