Make nat reflection src address configurable by introducing a reflection_src paramete...
[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("ipset",               device,    rule,     ipset),
32
33         FW3_LIST("proto",              protocol,  rule,     proto),
34
35         FW3_LIST("src_ip",             address,   rule,     ip_src),
36         FW3_LIST("src_mac",            mac,       rule,     mac_src),
37         FW3_LIST("src_port",           port,      rule,     port_src),
38
39         FW3_LIST("dest_ip",            address,   rule,     ip_dest),
40         FW3_LIST("dest_port",          port,      rule,     port_dest),
41
42         FW3_LIST("icmp_type",          icmptype,  rule,     icmp_type),
43         FW3_OPT("extra",               string,    rule,     extra),
44
45         FW3_OPT("limit",               limit,     rule,     limit),
46         FW3_OPT("limit_burst",         int,       rule,     limit.burst),
47
48         FW3_OPT("utc_time",            bool,      rule,     time.utc),
49         FW3_OPT("start_date",          date,      rule,     time.datestart),
50         FW3_OPT("stop_date",           date,      rule,     time.datestop),
51         FW3_OPT("start_time",          time,      rule,     time.timestart),
52         FW3_OPT("stop_time",           time,      rule,     time.timestop),
53         FW3_OPT("weekdays",            weekdays,  rule,     time.weekdays),
54         FW3_OPT("monthdays",           monthdays, rule,     time.monthdays),
55
56         FW3_OPT("target",              target,    rule,     target),
57
58         { }
59 };
60
61
62 void
63 fw3_load_rules(struct fw3_state *state, struct uci_package *p)
64 {
65         struct uci_section *s;
66         struct uci_element *e;
67         struct fw3_rule *rule;
68
69         INIT_LIST_HEAD(&state->rules);
70
71         uci_foreach_element(&p->sections, e)
72         {
73                 s = uci_to_section(e);
74
75                 if (strcmp(s->type, "rule"))
76                         continue;
77
78                 rule = malloc(sizeof(*rule));
79
80                 if (!rule)
81                         continue;
82
83                 memset(rule, 0, sizeof(*rule));
84
85                 INIT_LIST_HEAD(&rule->proto);
86
87                 INIT_LIST_HEAD(&rule->ip_src);
88                 INIT_LIST_HEAD(&rule->mac_src);
89                 INIT_LIST_HEAD(&rule->port_src);
90
91                 INIT_LIST_HEAD(&rule->ip_dest);
92                 INIT_LIST_HEAD(&rule->port_dest);
93
94                 INIT_LIST_HEAD(&rule->icmp_type);
95
96                 rule->enabled = true;
97
98                 fw3_parse_options(rule, fw3_rule_opts, s);
99
100                 if (!rule->enabled)
101                 {
102                         fw3_free_rule(rule);
103                         continue;
104                 }
105
106                 if (rule->src.invert || rule->dest.invert)
107                 {
108                         warn_elem(e, "must not have inverted 'src' or 'dest' options");
109                         fw3_free_rule(rule);
110                         continue;
111                 }
112                 else if (rule->src.set && !rule->src.any &&
113                          !(rule->_src = fw3_lookup_zone(state, rule->src.name, false)))
114                 {
115                         warn_elem(e, "refers to not existing zone '%s'", rule->src.name);
116                         fw3_free_rule(rule);
117                         continue;
118                 }
119                 else if (rule->dest.set && !rule->dest.any &&
120                          !(rule->_dest = fw3_lookup_zone(state, rule->dest.name, false)))
121                 {
122                         warn_elem(e, "refers to not existing zone '%s'", rule->dest.name);
123                         fw3_free_rule(rule);
124                         continue;
125                 }
126                 else if (rule->ipset.set && state->disable_ipsets)
127                 {
128                         warn_elem(e, "skipped due to disabled ipset support");
129                         fw3_free_rule(rule);
130                         continue;
131                 }
132                 else if (rule->ipset.set && !rule->ipset.any &&
133                          !(rule->_ipset = fw3_lookup_ipset(state, rule->ipset.name, false)))
134                 {
135                         warn_elem(e, "refers to unknown ipset '%s'", rule->ipset.name);
136                         fw3_free_rule(rule);
137                         continue;
138                 }
139
140                 if (!rule->_src && rule->target == FW3_FLAG_NOTRACK)
141                 {
142                         warn_elem(e, "is set to target NOTRACK but has no source assigned");
143                         fw3_free_rule(rule);
144                         continue;
145                 }
146
147                 if (!rule->_src && !rule->_dest && !rule->src.any && !rule->dest.any)
148                 {
149                         warn_elem(e, "has neither a source nor a destination zone assigned "
150                                      "- assuming an output rule");
151                 }
152
153                 if (rule->target == FW3_FLAG_UNSPEC)
154                 {
155                         warn_elem(e, "has no target specified, defaulting to REJECT");
156                         rule->target = FW3_FLAG_REJECT;
157                 }
158                 else if (rule->target > FW3_FLAG_NOTRACK)
159                 {
160                         warn_elem(e, "has invalid target specified, defaulting to REJECT");
161                         rule->target = FW3_FLAG_REJECT;
162                 }
163
164                 /* NB: rule family... */
165                 if (rule->_dest)
166                 {
167                         setbit(rule->_dest->flags[0], rule->target);
168                         setbit(rule->_dest->flags[1], rule->target);
169                 }
170
171                 list_add_tail(&rule->list, &state->rules);
172                 continue;
173         }
174 }
175
176
177 static void
178 print_chain(struct fw3_rule *rule)
179 {
180         char chain[256];
181
182         sprintf(chain, "delegate_output");
183
184         if (rule->target == FW3_FLAG_NOTRACK)
185         {
186                 sprintf(chain, "zone_%s_notrack", rule->src.name);
187         }
188         else
189         {
190                 if (rule->src.set)
191                 {
192                         if (!rule->src.any)
193                         {
194                                 if (rule->dest.set)
195                                         sprintf(chain, "zone_%s_forward", rule->src.name);
196                                 else
197                                         sprintf(chain, "zone_%s_input", rule->src.name);
198                         }
199                         else
200                         {
201                                 if (rule->dest.set)
202                                         sprintf(chain, "delegate_forward");
203                                 else
204                                         sprintf(chain, "delegate_input");
205                         }
206                 }
207
208                 if (rule->dest.set && !rule->src.set)
209                         sprintf(chain, "zone_%s_output", rule->dest.name);
210         }
211
212         fw3_pr("-A %s", chain);
213 }
214
215 static void print_target(struct fw3_rule *rule)
216 {
217         const char *target;
218
219         switch(rule->target)
220         {
221         case FW3_FLAG_ACCEPT:
222         case FW3_FLAG_DROP:
223         case FW3_FLAG_NOTRACK:
224                 target = fw3_flag_names[rule->target];
225                 break;
226
227         default:
228                 target = fw3_flag_names[FW3_FLAG_REJECT];
229                 break;
230         }
231
232         if (rule->dest.set && !rule->dest.any)
233                 fw3_pr(" -j zone_%s_dest_%s\n", rule->dest.name, target);
234         else if (rule->target == FW3_FLAG_REJECT)
235                 fw3_pr(" -j reject\n");
236         else
237                 fw3_pr(" -j %s\n", target);
238 }
239
240 static void
241 print_rule(enum fw3_table table, enum fw3_family family,
242            struct fw3_rule *rule, struct fw3_protocol *proto,
243            struct fw3_address *sip, struct fw3_address *dip,
244            struct fw3_port *sport, struct fw3_port *dport,
245            struct fw3_mac *mac, struct fw3_icmptype *icmptype)
246 {
247         if (!fw3_is_family(sip, family) || !fw3_is_family(dip, family))
248         {
249                 info("     ! Skipping due to different family of ip address");
250                 return;
251         }
252
253         if (proto->protocol == 58 && family == FW3_FAMILY_V4)
254         {
255                 info("     ! Skipping due to different family of protocol");
256                 return;
257         }
258
259         print_chain(rule);
260         fw3_format_ipset(rule->_ipset, rule->ipset.invert);
261         fw3_format_protocol(proto, family);
262         fw3_format_src_dest(sip, dip);
263         fw3_format_sport_dport(sport, dport);
264         fw3_format_icmptype(icmptype, family);
265         fw3_format_mac(mac);
266         fw3_format_limit(&rule->limit);
267         fw3_format_time(&rule->time);
268         fw3_format_extra(rule->extra);
269         fw3_format_comment(rule->name);
270         print_target(rule);
271 }
272
273 static void
274 expand_rule(enum fw3_table table, enum fw3_family family,
275             struct fw3_rule *rule, int num)
276 {
277         struct fw3_protocol *proto;
278         struct fw3_address *sip;
279         struct fw3_address *dip;
280         struct fw3_port *sport;
281         struct fw3_port *dport;
282         struct fw3_mac *mac;
283         struct fw3_icmptype *icmptype;
284
285         struct list_head *sports = NULL;
286         struct list_head *dports = NULL;
287         struct list_head *icmptypes = NULL;
288
289         struct list_head empty;
290         INIT_LIST_HEAD(&empty);
291
292         if (!fw3_is_family(rule, family))
293                 return;
294
295         if ((table == FW3_TABLE_RAW && rule->target != FW3_FLAG_NOTRACK) ||
296             (table != FW3_TABLE_FILTER))
297                 return;
298
299         if (rule->name)
300                 info("   * Rule '%s'", rule->name);
301         else
302                 info("   * Rule #%u", num);
303
304         if (!fw3_is_family(rule->_src, family) ||
305             !fw3_is_family(rule->_dest, family))
306         {
307                 info("     ! Skipping due to different family of zone");
308                 return;
309         }
310
311         if (rule->_ipset)
312         {
313                 if (!fw3_is_family(rule->_ipset, family))
314                 {
315                         info("     ! Skipping due to different family in ipset");
316                         return;
317                 }
318
319                 set(rule->_ipset->flags, family, family);
320         }
321
322         list_for_each_entry(proto, &rule->proto, list)
323         {
324                 /* icmp / ipv6-icmp */
325                 if (proto->protocol == 1 || proto->protocol == 58)
326                 {
327                         sports = &empty;
328                         dports = &empty;
329                         icmptypes = &rule->icmp_type;
330                 }
331                 else
332                 {
333                         sports = &rule->port_src;
334                         dports = &rule->port_dest;
335                         icmptypes = &empty;
336                 }
337
338                 fw3_foreach(sip, &rule->ip_src)
339                 fw3_foreach(dip, &rule->ip_dest)
340                 fw3_foreach(sport, sports)
341                 fw3_foreach(dport, dports)
342                 fw3_foreach(mac, &rule->mac_src)
343                 fw3_foreach(icmptype, icmptypes)
344                         print_rule(table, family, rule, proto, sip, dip, sport, dport,
345                                    mac, icmptype);
346         }
347 }
348
349 void
350 fw3_print_rules(enum fw3_table table, enum fw3_family family,
351                 struct fw3_state *state)
352 {
353         int num = 0;
354         struct fw3_rule *rule;
355
356         list_for_each_entry(rule, &state->rules, list)
357                 expand_rule(table, family, rule, num++);
358 }