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_TARGET_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_TARGET_UNSPEC)
 154                 {
 155                         warn_elem(e, "has no target specified, defaulting to REJECT");
 156                         rule->target = FW3_TARGET_REJECT;
 157                 }
 158                 else if (rule->target > FW3_TARGET_NOTRACK)
 159                 {
 160                         warn_elem(e, "has invalid target specified, defaulting to REJECT");
 161                         rule->target = FW3_TARGET_REJECT;
 162                 }
 163
 164                 if (rule->_dest)
 165                         setbit(rule->_dest->flags, rule->target);
 166
 167                 list_add_tail(&rule->list, &state->rules);
 168                 continue;
 169         }
 170 }
 171
 172
 173 static void
 174 print_chain(struct fw3_rule *rule)
 175 {
 176         char chain[256];
 177
 178         sprintf(chain, "delegate_output");
 179
 180         if (rule->target == FW3_TARGET_NOTRACK)
 181         {
 182                 sprintf(chain, "zone_%s_notrack", rule->src.name);
 183         }
 184         else
 185         {
 186                 if (rule->src.set)
 187                 {
 188                         if (!rule->src.any)
 189                         {
 190                                 if (rule->dest.set)
 191                                         sprintf(chain, "zone_%s_forward", rule->src.name);
 192                                 else
 193                                         sprintf(chain, "zone_%s_input", rule->src.name);
 194                         }
 195                         else
 196                         {
 197                                 if (rule->dest.set)
 198                                         sprintf(chain, "delegate_forward");
 199                                 else
 200                                         sprintf(chain, "delegate_input");
 201                         }
 202                 }
 203
 204                 if (rule->dest.set && !rule->src.set)
 205                         sprintf(chain, "zone_%s_output", rule->dest.name);
 206         }
 207
 208         fw3_pr("-A %s", chain);
 209 }
 210
 211 static void print_target(struct fw3_rule *rule)
 212 {
 213         const char *target;
 214
 215         switch(rule->target)
 216         {
 217         case FW3_TARGET_ACCEPT:
 218         case FW3_TARGET_DROP:
 219         case FW3_TARGET_NOTRACK:
 220                 target = fw3_flag_names[rule->target];
 221                 break;
 222
 223         default:
 224                 target = fw3_flag_names[FW3_TARGET_REJECT];
 225                 break;
 226         }
 227
 228         if (rule->dest.set && !rule->dest.any)
 229                 fw3_pr(" -j zone_%s_dest_%s\n", rule->dest.name, target);
 230         else if (rule->target == FW3_TARGET_REJECT)
 231                 fw3_pr(" -j reject\n");
 232         else
 233                 fw3_pr(" -j %s\n", target);
 234 }
 235
 236 static void
 237 print_rule(enum fw3_table table, enum fw3_family family,
 238            struct fw3_rule *rule, struct fw3_protocol *proto,
 239            struct fw3_address *sip, struct fw3_address *dip,
 240            struct fw3_port *sport, struct fw3_port *dport,
 241            struct fw3_mac *mac, struct fw3_icmptype *icmptype)
 242 {
 243         if (!fw3_is_family(sip, family) || !fw3_is_family(dip, family))
 244         {
 245                 info("     ! Skipping due to different family of ip address");
 246                 return;
 247         }
 248
 249         if (proto->protocol == 58 && family == FW3_FAMILY_V4)
 250         {
 251                 info("     ! Skipping due to different family of protocol");
 252                 return;
 253         }
 254
 255         print_chain(rule);
 256         fw3_format_ipset(rule->_ipset, rule->ipset.invert);
 257         fw3_format_protocol(proto, family);
 258         fw3_format_src_dest(sip, dip);
 259         fw3_format_sport_dport(sport, dport);
 260         fw3_format_icmptype(icmptype, family);
 261         fw3_format_mac(mac);
 262         fw3_format_limit(&rule->limit);
 263         fw3_format_time(&rule->time);
 264         fw3_format_extra(rule->extra);
 265         fw3_format_comment(rule->name);
 266         print_target(rule);
 267 }
 268
 269 static void
 270 expand_rule(enum fw3_table table, enum fw3_family family,
 271             struct fw3_rule *rule, int num)
 272 {
 273         struct fw3_protocol *proto;
 274         struct fw3_address *sip;
 275         struct fw3_address *dip;
 276         struct fw3_port *sport;
 277         struct fw3_port *dport;
 278         struct fw3_mac *mac;
 279         struct fw3_icmptype *icmptype;
 280
 281         struct list_head *sports = NULL;
 282         struct list_head *dports = NULL;
 283         struct list_head *icmptypes = NULL;
 284
 285         struct list_head empty;
 286         INIT_LIST_HEAD(&empty);
 287
 288         if (!fw3_is_family(rule, family))
 289                 return;
 290
 291         if ((table == FW3_TABLE_RAW && rule->target != FW3_TARGET_NOTRACK) ||
 292             (table != FW3_TABLE_FILTER))
 293                 return;
 294
 295         if (rule->name)
 296                 info("   * Rule '%s'", rule->name);
 297         else
 298                 info("   * Rule #%u", num);
 299
 300         if (!fw3_is_family(rule->_src, family) ||
 301             !fw3_is_family(rule->_dest, family))
 302         {
 303                 info("     ! Skipping due to different family of zone");
 304                 return;
 305         }
 306
 307         if (rule->_ipset)
 308         {
 309                 if (!fw3_is_family(rule->_ipset, family))
 310                 {
 311                         info("     ! Skipping due to different family in ipset");
 312                         return;
 313                 }
 314
 315                 setbit(rule->_ipset->flags, family);
 316         }
 317
 318         list_for_each_entry(proto, &rule->proto, list)
 319         {
 320                 /* icmp / ipv6-icmp */
 321                 if (proto->protocol == 1 || proto->protocol == 58)
 322                 {
 323                         sports = &empty;
 324                         dports = &empty;
 325                         icmptypes = &rule->icmp_type;
 326                 }
 327                 else
 328                 {
 329                         sports = &rule->port_src;
 330                         dports = &rule->port_dest;
 331                         icmptypes = &empty;
 332                 }
 333
 334                 fw3_foreach(sip, &rule->ip_src)
 335                 fw3_foreach(dip, &rule->ip_dest)
 336                 fw3_foreach(sport, sports)
 337                 fw3_foreach(dport, dports)
 338                 fw3_foreach(mac, &rule->mac_src)
 339                 fw3_foreach(icmptype, icmptypes)
 340                         print_rule(table, family, rule, proto, sip, dip, sport, dport,
 341                                    mac, icmptype);
 342         }
 343 }
 344
 345 void
 346 fw3_print_rules(enum fw3_table table, enum fw3_family family,
 347                 struct fw3_state *state)
 348 {
 349         int num = 0;
 350         struct fw3_rule *rule;
 351
 352         list_for_each_entry(rule, &state->rules, list)
 353                 expand_rule(table, family, rule, num++);
 354 }