Reapply SNAT/MASQUERADE rules on firewall reloads
[project/firewall3.git] / 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                         /* skip type for v6 if it does not support family */
111                         if (ipset->family != FW3_FAMILY_V4 &&
112                             !(ipset_types[i].optional & OPT_FAMILY))
113                                 continue;
114
115                         if (ipset_types[i].types == typelist)
116                         {
117                                 ipset->method = ipset_types[i].method;
118
119                                 warn_elem(e, "defines no storage method, assuming '%s'",
120                                           fw3_ipset_method_names[ipset->method]);
121
122                                 break;
123                         }
124                 }
125         }
126
127         //typelist |= ipset->method;
128
129         for (i = 0; i < ARRAY_SIZE(ipset_types); i++)
130         {
131                 if (ipset_types[i].method == ipset->method &&
132                     ipset_types[i].types == typelist)
133                 {
134                         if (!ipset->external)
135                         {
136                                 if ((ipset_types[i].required & OPT_IPRANGE) &&
137                                         !ipset->iprange.set)
138                                 {
139                                         warn_elem(e, "requires an ip range");
140                                         return false;
141                                 }
142
143                                 if ((ipset_types[i].required & OPT_PORTRANGE) &&
144                                     !ipset->portrange.set)
145                                 {
146                                         warn_elem(e, "requires a port range");
147                                         return false;
148                                 }
149
150                                 if (!(ipset_types[i].required & OPT_IPRANGE) &&
151                                     ipset->iprange.set)
152                                 {
153                                         warn_elem(e, "iprange ignored");
154                                         ipset->iprange.set = false;
155                                 }
156
157                                 if (!(ipset_types[i].required & OPT_PORTRANGE) &&
158                                     ipset->portrange.set)
159                                 {
160                                         warn_elem(e, "portrange ignored");
161                                         ipset->portrange.set = false;
162                                 }
163
164                                 if (!(ipset_types[i].optional & OPT_NETMASK) &&
165                                     ipset->netmask > 0)
166                                 {
167                                         warn_elem(e, "netmask ignored");
168                                         ipset->netmask = 0;
169                                 }
170
171                                 if (!(ipset_types[i].optional & OPT_HASHSIZE) &&
172                                     ipset->hashsize > 0)
173                                 {
174                                         warn_elem(e, "hashsize ignored");
175                                         ipset->hashsize = 0;
176                                 }
177
178                                 if (!(ipset_types[i].optional & OPT_MAXELEM) &&
179                                     ipset->maxelem > 0)
180                                 {
181                                         warn_elem(e, "maxelem ignored");
182                                         ipset->maxelem = 0;
183                                 }
184
185                                 if (!(ipset_types[i].optional & OPT_FAMILY) &&
186                                     ipset->family != FW3_FAMILY_V4)
187                                 {
188                                         warn_elem(e, "family ignored");
189                                         ipset->family = FW3_FAMILY_V4;
190                                 }
191                         }
192
193                         return true;
194                 }
195         }
196
197         warn_elem(e, "has an invalid combination of storage method and matches");
198         return false;
199 }
200
201 struct fw3_ipset *
202 fw3_alloc_ipset(void)
203 {
204         struct fw3_ipset *ipset;
205
206         ipset = malloc(sizeof(*ipset));
207
208         if (!ipset)
209                 return NULL;
210
211         memset(ipset, 0, sizeof(*ipset));
212
213         INIT_LIST_HEAD(&ipset->datatypes);
214
215         ipset->enabled = true;
216         ipset->family  = FW3_FAMILY_V4;
217
218         return ipset;
219 }
220
221 void
222 fw3_load_ipsets(struct fw3_state *state, struct uci_package *p)
223 {
224         struct uci_section *s;
225         struct uci_element *e;
226         struct fw3_ipset *ipset;
227
228         INIT_LIST_HEAD(&state->ipsets);
229
230         if (state->disable_ipsets)
231                 return;
232
233         uci_foreach_element(&p->sections, e)
234         {
235                 s = uci_to_section(e);
236
237                 if (strcmp(s->type, "ipset"))
238                         continue;
239
240                 ipset = fw3_alloc_ipset();
241
242                 if (!ipset)
243                         continue;
244
245                 fw3_parse_options(ipset, fw3_ipset_opts, s);
246
247                 if (ipset->external)
248                 {
249                         if (!*ipset->external)
250                                 ipset->external = NULL;
251                         else if (!ipset->name)
252                                 ipset->name = ipset->external;
253                 }
254
255                 if (!ipset->name || !*ipset->name)
256                 {
257                         warn_elem(e, "must have a name assigned");
258                 }
259                 //else if (fw3_lookup_ipset(state, ipset->name) != NULL)
260                 //{
261                 //      warn_elem(e, "has duplicated set name '%s'", ipset->name);
262                 //}
263                 else if (ipset->family == FW3_FAMILY_ANY)
264                 {
265                         warn_elem(e, "must not have family 'any'");
266                 }
267                 else if (ipset->iprange.set && ipset->family != ipset->iprange.family)
268                 {
269                         warn_elem(e, "has iprange of wrong address family");
270                 }
271                 else if (list_empty(&ipset->datatypes))
272                 {
273                         warn_elem(e, "has no datatypes assigned");
274                 }
275                 else if (check_types(e, ipset))
276                 {
277                         list_add_tail(&ipset->list, &state->ipsets);
278                         continue;
279                 }
280
281                 fw3_free_ipset(ipset);
282         }
283 }
284
285
286 static void
287 create_ipset(struct fw3_ipset *ipset, struct fw3_state *state)
288 {
289         bool first = true;
290
291         struct fw3_ipset_datatype *type;
292
293         info(" * Creating ipset %s", ipset->name);
294
295         first = true;
296         fw3_pr("create %s %s", ipset->name, fw3_ipset_method_names[ipset->method]);
297
298         list_for_each_entry(type, &ipset->datatypes, list)
299         {
300                 fw3_pr("%c%s", first ? ':' : ',', fw3_ipset_type_names[type->type]);
301                 first = false;
302         }
303
304         if (ipset->method == FW3_IPSET_METHOD_HASH)
305                 fw3_pr(" family inet%s", (ipset->family == FW3_FAMILY_V4) ? "" : "6");
306
307         if (ipset->iprange.set)
308         {
309                 fw3_pr(" range %s", fw3_address_to_string(&ipset->iprange, false));
310         }
311         else if (ipset->portrange.set)
312         {
313                 fw3_pr(" range %u-%u",
314                        ipset->portrange.port_min, ipset->portrange.port_max);
315         }
316
317         if (ipset->timeout > 0)
318                 fw3_pr(" timeout %u", ipset->timeout);
319
320         if (ipset->maxelem > 0)
321                 fw3_pr(" maxelem %u", ipset->maxelem);
322
323         if (ipset->netmask > 0)
324                 fw3_pr(" netmask %u", ipset->netmask);
325
326         if (ipset->hashsize > 0)
327                 fw3_pr(" hashsize %u", ipset->hashsize);
328
329         fw3_pr("\n");
330 }
331
332 void
333 fw3_create_ipsets(struct fw3_state *state)
334 {
335         int tries;
336         bool exec = false;
337         struct fw3_ipset *ipset;
338
339         if (state->disable_ipsets)
340                 return;
341
342         /* spawn ipsets */
343         list_for_each_entry(ipset, &state->ipsets, list)
344         {
345                 if (ipset->external)
346                         continue;
347
348                 if (!exec)
349                 {
350                         exec = fw3_command_pipe(false, "ipset", "-exist", "-");
351
352                         if (!exec)
353                                 return;
354                 }
355
356                 create_ipset(ipset, state);
357         }
358
359         if (exec)
360         {
361                 fw3_pr("quit\n");
362                 fw3_command_close();
363         }
364
365         /* wait for ipsets to appear */
366         list_for_each_entry(ipset, &state->ipsets, list)
367         {
368                 if (ipset->external)
369                         continue;
370
371                 for (tries = 0; !fw3_check_ipset(ipset) && tries < 10; tries++)
372                         usleep(50000);
373         }
374 }
375
376 void
377 fw3_destroy_ipsets(struct fw3_state *state)
378 {
379         int tries;
380         bool exec = false;
381         struct fw3_ipset *ipset;
382
383         /* destroy ipsets */
384         list_for_each_entry(ipset, &state->ipsets, list)
385         {
386                 if (!exec)
387                 {
388                         exec = fw3_command_pipe(false, "ipset", "-exist", "-");
389
390                         if (!exec)
391                                 return;
392                 }
393
394                 info(" * Deleting ipset %s", ipset->name);
395
396                 fw3_pr("flush %s\n", ipset->name);
397                 fw3_pr("destroy %s\n", ipset->name);
398         }
399
400         if (exec)
401         {
402                 fw3_pr("quit\n");
403                 fw3_command_close();
404         }
405
406         /* wait for ipsets to disappear */
407         list_for_each_entry(ipset, &state->ipsets, list)
408         {
409                 if (ipset->external)
410                         continue;
411
412                 for (tries = 0; fw3_check_ipset(ipset) && tries < 10; tries++)
413                         usleep(50000);
414         }
415 }
416
417 struct fw3_ipset *
418 fw3_lookup_ipset(struct fw3_state *state, const char *name)
419 {
420         struct fw3_ipset *s;
421
422         if (list_empty(&state->ipsets))
423                 return NULL;
424
425         list_for_each_entry(s, &state->ipsets, list)
426         {
427                 if (strcmp(s->name, name))
428                         continue;
429
430                 return s;
431         }
432
433         return NULL;
434 }
435
436 bool
437 fw3_check_ipset(struct fw3_ipset *set)
438 {
439         bool rv = false;
440
441         socklen_t sz;
442         int s = socket(AF_INET, SOCK_RAW, IPPROTO_RAW);
443         struct ip_set_req_version req_ver;
444         struct ip_set_req_get_set req_name;
445
446         if (s < 0 || fcntl(s, F_SETFD, FD_CLOEXEC))
447                 goto out;
448
449         sz = sizeof(req_ver);
450         req_ver.op = IP_SET_OP_VERSION;
451
452         if (getsockopt(s, SOL_IP, SO_IP_SET, &req_ver, &sz))
453                 goto out;
454
455         sz = sizeof(req_name);
456         req_name.op = IP_SET_OP_GET_BYNAME;
457         req_name.version = req_ver.version;
458         snprintf(req_name.set.name, IPSET_MAXNAMELEN - 1, "%s",
459                  set->external ? set->external : set->name);
460
461         if (getsockopt(s, SOL_IP, SO_IP_SET, &req_name, &sz))
462                 goto out;
463
464         rv = ((sz == sizeof(req_name)) && (req_name.set.index != IPSET_INVALID_ID));
465
466 out:
467         if (s >= 0)
468                 close(s);
469
470         return rv;
471 }