ipsets.c

   1 /*
   2  * firewall3 - 3rd OpenWrt UCI firewall implementation
   3  *
   4  *   Copyright (C) 2013 Jo-Philipp Wich <jow@openwrt.org>
   5  *
   6  * Permission to use, copy, modify, and/or distribute this software for any
   7  * purpose with or without fee is hereby granted, provided that the above
   8  * copyright notice and this permission notice appear in all copies.
   9  *
  10  * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
  11  * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
  12  * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
  13  * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
  14  * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
  15  * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
  16  * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
  17  */
  18
  19 #include "ipsets.h"
  20
  21
  22 const struct fw3_option fw3_ipset_opts[] = {
  23         FW3_OPT("enabled",       bool,           ipset,     enabled),
  24
  25         FW3_OPT("name",          string,         ipset,     name),
  26         FW3_OPT("family",        family,         ipset,     family),
  27
  28         FW3_OPT("storage",       ipset_method,   ipset,     method),
  29         FW3_LIST("match",        ipset_datatype, ipset,     datatypes),
  30
  31         FW3_OPT("iprange",       address,        ipset,     iprange),
  32         FW3_OPT("portrange",     port,           ipset,     portrange),
  33
  34         FW3_OPT("netmask",       int,            ipset,     netmask),
  35         FW3_OPT("maxelem",       int,            ipset,     maxelem),
  36         FW3_OPT("hashsize",      int,            ipset,     hashsize),
  37         FW3_OPT("timeout",       int,            ipset,     timeout),
  38
  39         FW3_OPT("external",      string,         ipset,     external),
  40
  41         { }
  42 };
  43
  44 #define T(m, t1, t2, t3, r, o) \
  45         { FW3_IPSET_METHOD_##m, \
  46           FW3_IPSET_TYPE_##t1 | (FW3_IPSET_TYPE_##t2 << 8) | (FW3_IPSET_TYPE_##t3 << 16), \
  47           r, o }
  48
  49 enum ipset_optflag {
  50         OPT_IPRANGE   = (1 << 0),
  51         OPT_PORTRANGE = (1 << 1),
  52         OPT_NETMASK   = (1 << 2),
  53         OPT_HASHSIZE  = (1 << 3),
  54         OPT_MAXELEM   = (1 << 4),
  55         OPT_FAMILY    = (1 << 5),
  56 };
  57
  58 struct ipset_type {
  59         enum fw3_ipset_method method;
  60         uint32_t types;
  61         uint8_t required;
  62         uint8_t optional;
  63 };
  64
  65 static struct ipset_type ipset_types[] = {
  66         T(BITMAP, IP,   UNSPEC, UNSPEC, OPT_IPRANGE, OPT_NETMASK),
  67         T(BITMAP, IP,   MAC,    UNSPEC, OPT_IPRANGE, 0),
  68         T(BITMAP, PORT, UNSPEC, UNSPEC, OPT_PORTRANGE, 0),
  69
  70         T(HASH,   IP,   UNSPEC, UNSPEC, 0,
  71           OPT_FAMILY | OPT_HASHSIZE | OPT_MAXELEM | OPT_NETMASK),
  72         T(HASH,   NET,  UNSPEC, UNSPEC, 0,
  73           OPT_FAMILY | OPT_HASHSIZE | OPT_MAXELEM),
  74         T(HASH,   IP,   PORT,   UNSPEC, 0,
  75           OPT_FAMILY | OPT_HASHSIZE | OPT_MAXELEM),
  76         T(HASH,   NET,  PORT,   UNSPEC, 0,
  77           OPT_FAMILY | OPT_HASHSIZE | OPT_MAXELEM),
  78         T(HASH,   IP,   PORT,   IP,     0,
  79           OPT_FAMILY | OPT_HASHSIZE | OPT_MAXELEM),
  80         T(HASH,   IP,   PORT,   NET,    0,
  81           OPT_FAMILY | OPT_HASHSIZE | OPT_MAXELEM),
  82
  83         T(LIST,   SET,  UNSPEC, UNSPEC, 0, OPT_MAXELEM),
  84 };
  85
  86
  87 static bool
  88 check_types(struct uci_element *e, struct fw3_ipset *ipset)
  89 {
  90         int i = 0;
  91         uint32_t typelist = 0;
  92         struct fw3_ipset_datatype *type;
  93
  94         list_for_each_entry(type, &ipset->datatypes, list)
  95         {
  96                 if (i >= 3)
  97                 {
  98                         warn_elem(e, "must not have more than 3 datatypes assigned");
  99                         return false;
 100                 }
 101
 102                 typelist |= (type->type << (i++ * 8));
 103         }
 104
 105         /* find a suitable storage method if none specified */
 106         if (ipset->method == FW3_IPSET_METHOD_UNSPEC)
 107         {
 108                 for (i = 0; i < ARRAY_SIZE(ipset_types); i++)
 109                 {
 110                         if (ipset_types[i].types == typelist)
 111                         {
 112                                 ipset->method = ipset_types[i].method;
 113
 114                                 warn_elem(e, "defines no storage method, assuming '%s'",
 115                                           fw3_ipset_method_names[ipset->method]);
 116
 117                                 break;
 118                         }
 119                 }
 120         }
 121
 122         //typelist |= ipset->method;
 123
 124         for (i = 0; i < ARRAY_SIZE(ipset_types); i++)
 125         {
 126                 if (ipset_types[i].method == ipset->method &&
 127                     ipset_types[i].types == typelist)
 128                 {
 129                         if (!ipset->external || !*ipset->external)
 130                         {
 131                                 if ((ipset_types[i].required & OPT_IPRANGE) &&
 132                                         !ipset->iprange.set)
 133                                 {
 134                                         warn_elem(e, "requires an ip range");
 135                                         return false;
 136                                 }
 137
 138                                 if ((ipset_types[i].required & OPT_PORTRANGE) &&
 139                                     !ipset->portrange.set)
 140                                 {
 141                                         warn_elem(e, "requires a port range");
 142                                         return false;
 143                                 }
 144
 145                                 if (!(ipset_types[i].required & OPT_IPRANGE) &&
 146                                     ipset->iprange.set)
 147                                 {
 148                                         warn_elem(e, "iprange ignored");
 149                                         ipset->iprange.set = false;
 150                                 }
 151
 152                                 if (!(ipset_types[i].required & OPT_PORTRANGE) &&
 153                                     ipset->portrange.set)
 154                                 {
 155                                         warn_elem(e, "portrange ignored");
 156                                         ipset->portrange.set = false;
 157                                 }
 158
 159                                 if (!(ipset_types[i].optional & OPT_NETMASK) &&
 160                                     ipset->netmask > 0)
 161                                 {
 162                                         warn_elem(e, "netmask ignored");
 163                                         ipset->netmask = 0;
 164                                 }
 165
 166                                 if (!(ipset_types[i].optional & OPT_HASHSIZE) &&
 167                                     ipset->hashsize > 0)
 168                                 {
 169                                         warn_elem(e, "hashsize ignored");
 170                                         ipset->hashsize = 0;
 171                                 }
 172
 173                                 if (!(ipset_types[i].optional & OPT_MAXELEM) &&
 174                                     ipset->maxelem > 0)
 175                                 {
 176                                         warn_elem(e, "maxelem ignored");
 177                                         ipset->maxelem = 0;
 178                                 }
 179
 180                                 if (!(ipset_types[i].optional & OPT_FAMILY) &&
 181                                     ipset->family != FW3_FAMILY_ANY)
 182                                 {
 183                                         warn_elem(e, "family ignored");
 184                                         ipset->family = FW3_FAMILY_ANY;
 185                                 }
 186                         }
 187
 188                         return true;
 189                 }
 190         }
 191
 192         warn_elem(e, "has an invalid combination of storage method and matches");
 193         return false;
 194 }
 195
 196 struct fw3_ipset *
 197 fw3_alloc_ipset(void)
 198 {
 199         struct fw3_ipset *ipset;
 200
 201         ipset = malloc(sizeof(*ipset));
 202
 203         if (!ipset)
 204                 return NULL;
 205
 206         memset(ipset, 0, sizeof(*ipset));
 207
 208         INIT_LIST_HEAD(&ipset->datatypes);
 209
 210         ipset->enabled = true;
 211
 212         return ipset;
 213 }
 214
 215 void
 216 fw3_load_ipsets(struct fw3_state *state, struct uci_package *p)
 217 {
 218         struct uci_section *s;
 219         struct uci_element *e;
 220         struct fw3_ipset *ipset;
 221
 222         INIT_LIST_HEAD(&state->ipsets);
 223
 224         if (state->disable_ipsets)
 225                 return;
 226
 227         uci_foreach_element(&p->sections, e)
 228         {
 229                 s = uci_to_section(e);
 230
 231                 if (strcmp(s->type, "ipset"))
 232                         continue;
 233
 234                 ipset = fw3_alloc_ipset();
 235
 236                 if (!ipset)
 237                         continue;
 238
 239                 fw3_parse_options(ipset, fw3_ipset_opts, s);
 240
 241                 if (!ipset->name || !*ipset->name)
 242                 {
 243                         warn_elem(e, "must have a name assigned");
 244                 }
 245                 //else if (fw3_lookup_ipset(state, ipset->name) != NULL)
 246                 //{
 247                 //      warn_elem(e, "has duplicated set name '%s'", ipset->name);
 248                 //}
 249                 else if (list_empty(&ipset->datatypes))
 250                 {
 251                         warn_elem(e, "has no datatypes assigned");
 252                 }
 253                 else if (check_types(e, ipset))
 254                 {
 255                         list_add_tail(&ipset->list, &state->ipsets);
 256                         continue;
 257                 }
 258
 259                 fw3_free_ipset(ipset);
 260         }
 261 }
 262
 263
 264 static void
 265 create_ipset(struct fw3_ipset *ipset, struct fw3_state *state)
 266 {
 267         bool first = true;
 268
 269         struct fw3_ipset_datatype *type;
 270
 271         if (ipset->external && *ipset->external)
 272                 return;
 273
 274         info(" * Creating ipset %s", ipset->name);
 275
 276         first = true;
 277         fw3_pr("create %s %s", ipset->name, fw3_ipset_method_names[ipset->method]);
 278
 279         list_for_each_entry(type, &ipset->datatypes, list)
 280         {
 281                 fw3_pr("%c%s", first ? ':' : ',', fw3_ipset_type_names[type->type]);
 282                 first = false;
 283         }
 284
 285         if (ipset->iprange.set)
 286         {
 287                 fw3_pr(" range %s", fw3_address_to_string(&ipset->iprange, false));
 288         }
 289         else if (ipset->portrange.set)
 290         {
 291                 fw3_pr(" range %u-%u",
 292                        ipset->portrange.port_min, ipset->portrange.port_max);
 293         }
 294
 295         if (ipset->family != FW3_FAMILY_ANY)
 296                 fw3_pr(" family inet%s", (ipset->family == FW3_FAMILY_V4) ? "" : "6");
 297
 298         if (ipset->timeout > 0)
 299                 fw3_pr(" timeout %u", ipset->timeout);
 300
 301         if (ipset->maxelem > 0)
 302                 fw3_pr(" maxelem %u", ipset->maxelem);
 303
 304         if (ipset->netmask > 0)
 305                 fw3_pr(" netmask %u", ipset->netmask);
 306
 307         if (ipset->hashsize > 0)
 308                 fw3_pr(" hashsize %u", ipset->hashsize);
 309
 310         fw3_pr("\n");
 311 }
 312
 313 void
 314 fw3_create_ipsets(struct fw3_state *state)
 315 {
 316         struct fw3_ipset *ipset;
 317
 318         if (state->disable_ipsets)
 319                 return;
 320
 321         list_for_each_entry(ipset, &state->ipsets, list)
 322                 create_ipset(ipset, state);
 323
 324         fw3_pr("quit\n");
 325 }
 326
 327 void
 328 fw3_destroy_ipsets(struct fw3_state *state)
 329 {
 330         struct fw3_ipset *s;
 331
 332         list_for_each_entry(s, &state->ipsets, list)
 333         {
 334                 info(" * Deleting ipset %s", s->name);
 335
 336                 fw3_pr("flush %s\n", s->name);
 337                 fw3_pr("destroy %s\n", s->name);
 338         }
 339
 340         fw3_pr("quit\n");
 341 }
 342
 343 struct fw3_ipset *
 344 fw3_lookup_ipset(struct fw3_state *state, const char *name)
 345 {
 346         struct fw3_ipset *s;
 347
 348         if (list_empty(&state->ipsets))
 349                 return NULL;
 350
 351         list_for_each_entry(s, &state->ipsets, list)
 352         {
 353                 if (strcmp(s->name, name))
 354                         continue;
 355
 356                 return s;
 357         }
 358
 359         return NULL;
 360 }
 361
 362 bool
 363 fw3_check_ipset(struct fw3_ipset *set)
 364 {
 365         bool rv = false;
 366
 367         socklen_t sz;
 368         int s = socket(AF_INET, SOCK_RAW, IPPROTO_RAW);
 369         struct ip_set_req_version req_ver;
 370         struct ip_set_req_get_set req_name;
 371
 372         if (s < 0 || fcntl(s, F_SETFD, FD_CLOEXEC))
 373                 goto out;
 374
 375         sz = sizeof(req_ver);
 376         req_ver.op = IP_SET_OP_VERSION;
 377
 378         if (getsockopt(s, SOL_IP, SO_IP_SET, &req_ver, &sz))
 379                 goto out;
 380
 381         sz = sizeof(req_name);
 382         req_name.op = IP_SET_OP_GET_BYNAME;
 383         req_name.version = req_ver.version;
 384         snprintf(req_name.set.name, IPSET_MAXNAMELEN - 1, "%s",
 385                  (set->external && *set->external) ? set->external : set->name);
 386
 387         if (getsockopt(s, SOL_IP, SO_IP_SET, &req_name, &sz))
 388                 goto out;
 389
 390         rv = ((sz == sizeof(req_name)) && (req_name.set.index != IPSET_INVALID_ID));
 391
 392 out:
 393         if (s >= 0)
 394                 close(s);
 395
 396         return rv;
 397 }