756c78dc47c9fa11ab4ff7af282ec0e53b70580c
[project/firewall3.git] / rules.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 "rules.h"
20
21
22 const struct fw3_option fw3_rule_opts[] = {
23 FW3_OPT("enabled", bool, rule, enabled),
24
25 FW3_OPT("name", string, rule, name),
26 FW3_OPT("family", family, rule, family),
27
28 FW3_OPT("src", device, rule, src),
29 FW3_OPT("dest", device, rule, dest),
30
31 FW3_OPT("device", string, rule, device),
32 FW3_OPT("direction", direction, rule, direction_out),
33
34 FW3_OPT("ipset", setmatch, rule, ipset),
35
36 FW3_LIST("proto", protocol, rule, proto),
37
38 FW3_LIST("src_ip", network, rule, ip_src),
39 FW3_LIST("src_mac", mac, rule, mac_src),
40 FW3_LIST("src_port", port, rule, port_src),
41
42 FW3_LIST("dest_ip", network, rule, ip_dest),
43 FW3_LIST("dest_port", port, rule, port_dest),
44
45 FW3_LIST("icmp_type", icmptype, rule, icmp_type),
46 FW3_OPT("extra", string, rule, extra),
47
48 FW3_OPT("limit", limit, rule, limit),
49 FW3_OPT("limit_burst", int, rule, limit.burst),
50
51 FW3_OPT("utc_time", bool, rule, time.utc),
52 FW3_OPT("start_date", date, rule, time.datestart),
53 FW3_OPT("stop_date", date, rule, time.datestop),
54 FW3_OPT("start_time", time, rule, time.timestart),
55 FW3_OPT("stop_time", time, rule, time.timestop),
56 FW3_OPT("weekdays", weekdays, rule, time.weekdays),
57 FW3_OPT("monthdays", monthdays, rule, time.monthdays),
58
59 FW3_OPT("mark", mark, rule, mark),
60 FW3_OPT("set_mark", mark, rule, set_mark),
61 FW3_OPT("set_xmark", mark, rule, set_xmark),
62
63 FW3_OPT("target", target, rule, target),
64
65 { }
66 };
67
68
69 static bool
70 need_src_action_chain(struct fw3_rule *r)
71 {
72 return (r->_src && r->_src->log && (r->target > FW3_FLAG_ACCEPT));
73 }
74
75 static struct fw3_rule*
76 alloc_rule(struct fw3_state *state)
77 {
78 struct fw3_rule *rule = calloc(1, sizeof(*rule));
79
80 if (rule) {
81 INIT_LIST_HEAD(&rule->proto);
82
83 INIT_LIST_HEAD(&rule->ip_src);
84 INIT_LIST_HEAD(&rule->mac_src);
85 INIT_LIST_HEAD(&rule->port_src);
86
87 INIT_LIST_HEAD(&rule->ip_dest);
88 INIT_LIST_HEAD(&rule->port_dest);
89
90 INIT_LIST_HEAD(&rule->icmp_type);
91
92 list_add_tail(&rule->list, &state->rules);
93 rule->enabled = true;
94 }
95
96 return rule;
97 }
98
99 void
100 fw3_load_rules(struct fw3_state *state, struct uci_package *p,
101 struct blob_attr *a)
102 {
103 struct uci_section *s;
104 struct uci_element *e;
105 struct fw3_rule *rule, *n;
106 struct blob_attr *entry, *opt;
107 unsigned rem, orem;
108
109 INIT_LIST_HEAD(&state->rules);
110
111 blob_for_each_attr(entry, a, rem) {
112 const char *type = NULL;
113 const char *name = "ubus rule";
114 blobmsg_for_each_attr(opt, entry, orem)
115 if (!strcmp(blobmsg_name(opt), "type"))
116 type = blobmsg_get_string(opt);
117 else if (!strcmp(blobmsg_name(opt), "name"))
118 name = blobmsg_get_string(opt);
119
120 if (!type || strcmp(type, "rule"))
121 continue;
122
123 if (!(rule = alloc_rule(state)))
124 continue;
125
126 if (!fw3_parse_blob_options(rule, fw3_rule_opts, entry, name))
127 {
128 fprintf(stderr, "%s skipped due to invalid options\n", name);
129 fw3_free_rule(rule);
130 continue;
131 }
132 }
133
134 uci_foreach_element(&p->sections, e)
135 {
136 s = uci_to_section(e);
137
138 if (strcmp(s->type, "rule"))
139 continue;
140
141 if (!(rule = alloc_rule(state)))
142 continue;
143
144 if (!fw3_parse_options(rule, fw3_rule_opts, s))
145 {
146 warn_elem(e, "skipped due to invalid options");
147 fw3_free_rule(rule);
148 continue;
149 }
150 }
151
152 list_for_each_entry_safe(rule, n, &state->rules, list)
153 {
154 if (!rule->enabled)
155 {
156 fw3_free_rule(rule);
157 continue;
158 }
159
160 if (rule->src.invert || rule->dest.invert)
161 {
162 warn_elem(e, "must not have inverted 'src' or 'dest' options");
163 fw3_free_rule(rule);
164 continue;
165 }
166 else if (rule->src.set && !rule->src.any &&
167 !(rule->_src = fw3_lookup_zone(state, rule->src.name)))
168 {
169 warn_elem(e, "refers to not existing zone '%s'", rule->src.name);
170 fw3_free_rule(rule);
171 continue;
172 }
173 else if (rule->dest.set && !rule->dest.any &&
174 !(rule->_dest = fw3_lookup_zone(state, rule->dest.name)))
175 {
176 warn_elem(e, "refers to not existing zone '%s'", rule->dest.name);
177 fw3_free_rule(rule);
178 continue;
179 }
180 else if (rule->ipset.set && state->disable_ipsets)
181 {
182 warn_elem(e, "skipped due to disabled ipset support");
183 fw3_free_rule(rule);
184 continue;
185 }
186 else if (rule->ipset.set &&
187 !(rule->ipset.ptr = fw3_lookup_ipset(state, rule->ipset.name)))
188 {
189 warn_elem(e, "refers to unknown ipset '%s'", rule->ipset.name);
190 fw3_free_rule(rule);
191 continue;
192 }
193
194 if (!rule->_src && rule->target == FW3_FLAG_NOTRACK)
195 {
196 warn_elem(e, "is set to target NOTRACK but has no source assigned");
197 fw3_free_rule(rule);
198 continue;
199 }
200
201 if (!rule->set_mark.set && !rule->set_xmark.set &&
202 rule->target == FW3_FLAG_MARK)
203 {
204 warn_elem(e, "is set to target MARK but specifies neither "
205 "'set_mark' nor 'set_xmark' option");
206 fw3_free_rule(rule);
207 continue;
208 }
209
210 if (rule->_dest && rule->target == FW3_FLAG_MARK)
211 {
212 warn_elem(e, "must not specify 'dest' for MARK target");
213 fw3_free_rule(rule);
214 continue;
215 }
216
217 if (rule->set_mark.invert || rule->set_xmark.invert)
218 {
219 warn_elem(e, "must not have inverted 'set_mark' or 'set_xmark'");
220 fw3_free_rule(rule);
221 continue;
222 }
223
224 if (!rule->_src && !rule->_dest && !rule->src.any && !rule->dest.any)
225 {
226 warn_elem(e, "has neither a source nor a destination zone assigned "
227 "- assuming an output rule");
228 }
229
230 if (list_empty(&rule->proto))
231 {
232 warn_elem(e, "does not specify a protocol, assuming TCP+UDP");
233 fw3_parse_protocol(&rule->proto, "tcpudp", true);
234 }
235
236 if (rule->target == FW3_FLAG_UNSPEC)
237 {
238 warn_elem(e, "has no target specified, defaulting to REJECT");
239 rule->target = FW3_FLAG_REJECT;
240 }
241 else if (rule->target > FW3_FLAG_MARK)
242 {
243 warn_elem(e, "has invalid target specified, defaulting to REJECT");
244 rule->target = FW3_FLAG_REJECT;
245 }
246
247 /* NB: rule family... */
248 if (rule->_dest)
249 {
250 setbit(rule->_dest->flags[0], rule->target);
251 setbit(rule->_dest->flags[1], rule->target);
252 }
253 else if (need_src_action_chain(rule))
254 {
255 setbit(rule->_src->flags[0], fw3_to_src_target(rule->target));
256 setbit(rule->_src->flags[1], fw3_to_src_target(rule->target));
257 }
258 }
259 }
260
261
262 static void
263 append_chain(struct fw3_ipt_rule *r, struct fw3_rule *rule)
264 {
265 char chain[32];
266
267 snprintf(chain, sizeof(chain), "OUTPUT");
268
269 if (rule->target == FW3_FLAG_NOTRACK)
270 {
271 snprintf(chain, sizeof(chain), "zone_%s_notrack", rule->src.name);
272 }
273 else if (rule->target == FW3_FLAG_MARK)
274 {
275 snprintf(chain, sizeof(chain), "PREROUTING");
276 }
277 else
278 {
279 if (rule->src.set)
280 {
281 if (!rule->src.any)
282 {
283 if (rule->dest.set)
284 snprintf(chain, sizeof(chain), "zone_%s_forward",
285 rule->src.name);
286 else
287 snprintf(chain, sizeof(chain), "zone_%s_input",
288 rule->src.name);
289 }
290 else
291 {
292 if (rule->dest.set)
293 snprintf(chain, sizeof(chain), "FORWARD");
294 else
295 snprintf(chain, sizeof(chain), "INPUT");
296 }
297 }
298
299 if (rule->dest.set && !rule->src.set)
300 {
301 if (rule->dest.any)
302 snprintf(chain, sizeof(chain), "OUTPUT");
303 else
304 snprintf(chain, sizeof(chain), "zone_%s_output",
305 rule->dest.name);
306 }
307 }
308
309 fw3_ipt_rule_append(r, chain);
310 }
311
312 static void set_target(struct fw3_ipt_rule *r, struct fw3_rule *rule)
313 {
314 const char *name;
315 struct fw3_mark *mark;
316 char buf[sizeof("0xFFFFFFFF/0xFFFFFFFF\0")];
317
318 switch(rule->target)
319 {
320 case FW3_FLAG_MARK:
321 name = rule->set_mark.set ? "--set-mark" : "--set-xmark";
322 mark = rule->set_mark.set ? &rule->set_mark : &rule->set_xmark;
323 sprintf(buf, "0x%x/0x%x", mark->mark, mark->mask);
324
325 fw3_ipt_rule_target(r, "MARK");
326 fw3_ipt_rule_addarg(r, false, name, buf);
327 return;
328
329 case FW3_FLAG_NOTRACK:
330 fw3_ipt_rule_target(r, "CT");
331 fw3_ipt_rule_addarg(r, false, "--notrack", NULL);
332 return;
333
334 case FW3_FLAG_ACCEPT:
335 case FW3_FLAG_DROP:
336 name = fw3_flag_names[rule->target];
337 break;
338
339 default:
340 name = fw3_flag_names[FW3_FLAG_REJECT];
341 break;
342 }
343
344 if (rule->dest.set && !rule->dest.any)
345 fw3_ipt_rule_target(r, "zone_%s_dest_%s", rule->dest.name, name);
346 else if (need_src_action_chain(rule))
347 fw3_ipt_rule_target(r, "zone_%s_src_%s", rule->src.name, name);
348 else if (strcmp(name, "REJECT"))
349 fw3_ipt_rule_target(r, name);
350 else
351 fw3_ipt_rule_target(r, "reject");
352 }
353
354 static void
355 set_comment(struct fw3_ipt_rule *r, const char *name, int num)
356 {
357 if (name)
358 fw3_ipt_rule_comment(r, name);
359 else
360 fw3_ipt_rule_comment(r, "@rule[%u]", num);
361 }
362
363 static void
364 print_rule(struct fw3_ipt_handle *handle, struct fw3_state *state,
365 struct fw3_rule *rule, int num, struct fw3_protocol *proto,
366 struct fw3_address *sip, struct fw3_address *dip,
367 struct fw3_port *sport, struct fw3_port *dport,
368 struct fw3_mac *mac, struct fw3_icmptype *icmptype)
369 {
370 struct fw3_ipt_rule *r;
371
372 if (!fw3_is_family(sip, handle->family) ||
373 !fw3_is_family(dip, handle->family))
374 {
375 if ((sip && !sip->resolved) || (dip && !dip->resolved))
376 info(" ! Skipping due to different family of ip address");
377
378 return;
379 }
380
381 if (proto->protocol == 58 && handle->family == FW3_FAMILY_V4)
382 {
383 info(" ! Skipping due to different family of protocol");
384 return;
385 }
386
387 r = fw3_ipt_rule_create(handle, proto, NULL, NULL, sip, dip);
388 fw3_ipt_rule_sport_dport(r, sport, dport);
389 fw3_ipt_rule_device(r, rule->device, rule->direction_out);
390 fw3_ipt_rule_icmptype(r, icmptype);
391 fw3_ipt_rule_mac(r, mac);
392 fw3_ipt_rule_ipset(r, &rule->ipset);
393 fw3_ipt_rule_limit(r, &rule->limit);
394 fw3_ipt_rule_time(r, &rule->time);
395 fw3_ipt_rule_mark(r, &rule->mark);
396 set_target(r, rule);
397 fw3_ipt_rule_extra(r, rule->extra);
398 set_comment(r, rule->name, num);
399 append_chain(r, rule);
400 }
401
402 static void
403 expand_rule(struct fw3_ipt_handle *handle, struct fw3_state *state,
404 struct fw3_rule *rule, int num)
405 {
406 struct fw3_protocol *proto;
407 struct fw3_address *sip;
408 struct fw3_address *dip;
409 struct fw3_port *sport;
410 struct fw3_port *dport;
411 struct fw3_mac *mac;
412 struct fw3_icmptype *icmptype;
413
414 struct list_head *sports = NULL;
415 struct list_head *dports = NULL;
416 struct list_head *icmptypes = NULL;
417
418 struct list_head empty;
419 INIT_LIST_HEAD(&empty);
420
421 if (!fw3_is_family(rule, handle->family))
422 return;
423
424 if ((rule->target == FW3_FLAG_NOTRACK && handle->table != FW3_TABLE_RAW) ||
425 (rule->target == FW3_FLAG_MARK && handle->table != FW3_TABLE_MANGLE) ||
426 (rule->target < FW3_FLAG_NOTRACK && handle->table != FW3_TABLE_FILTER))
427 return;
428
429 if (rule->name)
430 info(" * Rule '%s'", rule->name);
431 else
432 info(" * Rule #%u", num);
433
434 if (!fw3_is_family(rule->_src, handle->family) ||
435 !fw3_is_family(rule->_dest, handle->family))
436 {
437 info(" ! Skipping due to different family of zone");
438 return;
439 }
440
441 if (rule->ipset.ptr)
442 {
443 if (!fw3_is_family(rule->ipset.ptr, handle->family))
444 {
445 info(" ! Skipping due to different family in ipset");
446 return;
447 }
448
449 if (!fw3_check_ipset(rule->ipset.ptr))
450 {
451 info(" ! Skipping due to missing ipset '%s'",
452 rule->ipset.ptr->external
453 ? rule->ipset.ptr->external : rule->ipset.ptr->name);
454 return;
455 }
456
457 set(rule->ipset.ptr->flags, handle->family, handle->family);
458 }
459
460 list_for_each_entry(proto, &rule->proto, list)
461 {
462 /* icmp / ipv6-icmp */
463 if (proto->protocol == 1 || proto->protocol == 58)
464 {
465 sports = &empty;
466 dports = &empty;
467 icmptypes = &rule->icmp_type;
468 }
469 else
470 {
471 sports = &rule->port_src;
472 dports = &rule->port_dest;
473 icmptypes = &empty;
474 }
475
476 fw3_foreach(sip, &rule->ip_src)
477 fw3_foreach(dip, &rule->ip_dest)
478 fw3_foreach(sport, sports)
479 fw3_foreach(dport, dports)
480 fw3_foreach(mac, &rule->mac_src)
481 fw3_foreach(icmptype, icmptypes)
482 print_rule(handle, state, rule, num, proto, sip, dip,
483 sport, dport, mac, icmptype);
484 }
485 }
486
487 void
488 fw3_print_rules(struct fw3_ipt_handle *handle, struct fw3_state *state)
489 {
490 int num = 0;
491 struct fw3_rule *rule;
492
493 list_for_each_entry(rule, &state->rules, list)
494 expand_rule(handle, state, rule, num++);
495 }