contrib/fwd/src/fwd.c

   1 /*
   2  * fwd - OpenWrt firewall daemon - main part
   3  *
   4  *   Copyright (C) 2009 Jo-Philipp Wich <xm@subsignal.org>
   5  *
   6  * The fwd program is free software: you can redistribute it and/or
   7  * modify it under the terms of the GNU General Public License version 2
   8  * as published by the Free Software Foundation.
   9  *
  10  * The fwd program is distributed in the hope that it will be useful,
  11  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  12  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
  13  * See the GNU General Public License for more details.
  14  *
  15  * You should have received a copy of the GNU General Public License along
  16  * with the fwd program. If not, see http://www.gnu.org/licenses/.
  17  */
  18
  19
  20 #include "fwd.h"
  21 #include "fwd_addr.h"
  22 #include "fwd_rules.h"
  23 #include "fwd_config.h"
  24 #include "fwd_xtables.h"
  25 #include "fwd_ipc.h"
  26 #include "fwd_utils.h"
  27
  28
  29 static void fwd_foreach_network(
  30         struct fwd_handle *h,
  31         void (*cb)(struct fwd_handle *h, struct fwd_network *net)
  32 ) {
  33         struct fwd_data *data;
  34         struct fwd_network *net;
  35
  36         for( data = h->conf; data; data = data->next )
  37         {
  38                 if( data->type != FWD_S_ZONE )
  39                         continue;
  40
  41                 for( net = data->section.zone.networks; net; net = net->next )
  42                         cb(h, net);
  43         }
  44 }
  45
  46 static void fwd_addif_all_cb(struct fwd_handle *h, struct fwd_network *net)
  47 {
  48         fwd_ipt_addif(h, net->name);
  49 }
  50
  51 static void fwd_delif_all_cb(struct fwd_handle *h, struct fwd_network *net)
  52 {
  53         fwd_ipt_delif(h, net->name);
  54 }
  55
  56 #define fwd_addif_all(h) fwd_foreach_network(h, fwd_addif_all_cb)
  57 #define fwd_delif_all(h) fwd_foreach_network(h, fwd_delif_all_cb)
  58
  59
  60 static int fwd_server_main(int argc, const char *argv[])
  61 {
  62         struct fwd_handle *h;
  63         struct fwd_network *net;
  64         struct fwd_addr *addrs;
  65         struct fwd_data *data;
  66         struct fwd_cidr *addr_old, *addr_new;
  67         struct sigaction sa;
  68         int unix_client;
  69
  70         sa.sa_handler = SIG_IGN;
  71         sigaction(SIGPIPE, &sa, NULL);
  72
  73         if( getuid() > 0 )
  74                 fwd_fatal("Need root permissions!");
  75
  76         if( !(h = fwd_alloc_ptr(struct fwd_handle)) )
  77                 fwd_fatal("Out of memory");
  78
  79         if( (h->rtnl_socket = socket(AF_NETLINK, SOCK_RAW, NETLINK_ROUTE)) == -1 )
  80                 fwd_fatal("Failed to create AF_NETLINK socket (%m)");
  81
  82         if( (h->unix_socket = fwd_ipc_listen()) == -1 )
  83                 fwd_fatal("Failed to create AF_UNIX socket (%m)");
  84
  85         if( !(h->conf = fwd_read_config(h)) )
  86                 fwd_fatal("Failed to read configuration");
  87
  88         fwd_log_init();
  89
  90         fwd_ipt_build_ruleset(h);
  91         fwd_addif_all(h);
  92
  93         while(1)
  94         {
  95                 if( (addrs = fwd_get_addrs(h->rtnl_socket, AF_INET)) != NULL )
  96                 {
  97                         for( data = h->conf; data; data = data->next )
  98                         {
  99                                 if( data->type != FWD_S_ZONE )
 100                                         continue;
 101
 102                                 for( net = data->section.zone.networks; net; net = net->next )
 103                                 {
 104                                         addr_new = fwd_lookup_addr(addrs, net->ifname);
 105                                         addr_old = net->addr;
 106
 107                                         if( !fwd_empty_cidr(addr_new) && fwd_empty_cidr(addr_old) )
 108                                         {
 109                                                 printf("IFUP[%s]\n", net->ifname);
 110                                                 fwd_update_cidr(addr_old, addr_new);
 111                                                 fwd_ipt_addif(h, net->name);
 112                                         }
 113                                         else if( fwd_empty_cidr(addr_new) && !fwd_empty_cidr(addr_old) )
 114                                         {
 115                                                 printf("IFDOWN[%s]\n", net->ifname);
 116                                                 fwd_update_cidr(addr_old, NULL);
 117                                                 fwd_ipt_delif(h, net->name);
 118                                         }
 119                                         else if( ! fwd_equal_cidr(addr_old, addr_new) )
 120                                         {
 121                                                 printf("IFCHANGE[%s]\n", net->ifname);
 122                                                 fwd_update_cidr(addr_old, addr_new);
 123                                                 fwd_ipt_chgif(h, net->name);
 124                                         }
 125                                 }
 126                         }
 127
 128                         fwd_free_addrs(addrs);
 129                 }
 130
 131
 132                 if( (unix_client = fwd_ipc_accept(h->unix_socket)) > -1 )
 133                 {
 134                         struct fwd_ipc_msg msg;
 135                         memset(&msg, 0, sizeof(struct fwd_ipc_msg));
 136
 137                         while( fwd_ipc_recvmsg(unix_client, &msg, sizeof(struct fwd_ipc_msg)) > 0 )
 138                         {
 139                                 fwd_log_info("Got message [%i]", msg.type);
 140
 141                                 switch(msg.type)
 142                                 {
 143                                         case FWD_IPC_FLUSH:
 144                                                 fwd_log_info("Flushing rules ...");
 145                                                 fwd_ipt_clear_ruleset(h);
 146                                                 fwd_ipc_sendtype(unix_client, FWD_IPC_OK);
 147                                                 break;
 148
 149                                         case FWD_IPC_BUILD:
 150                                                 fwd_log_info("Building rules ...");
 151                                                 fwd_ipt_clear_ruleset(h);
 152                                                 fwd_ipt_build_ruleset(h);
 153                                                 fwd_addif_all(h);
 154                                                 fwd_ipc_sendtype(unix_client, FWD_IPC_OK);
 155                                                 break;
 156
 157                                         case FWD_IPC_RELOAD:
 158                                                 if( (data = fwd_read_config(h)) != NULL )
 159                                                 {
 160                                                         fwd_log_info("Flushing rules ...");
 161                                                         fwd_ipt_clear_ruleset(h);
 162                                                         fwd_free_config(h->conf);
 163                                                         h->conf = data;
 164                                                         fwd_log_info("Building rules ...");
 165                                                         fwd_ipt_build_ruleset(h);
 166                                                         fwd_addif_all(h);
 167                                                         fwd_ipc_sendtype(unix_client, FWD_IPC_OK);
 168                                                 }
 169                                                 else
 170                                                 {
 171                                                         fwd_log_err("Cannot reload configuration!");
 172                                                         fwd_ipc_sendtype(unix_client, FWD_IPC_ERROR);
 173                                                 }
 174                                                 break;
 175
 176                                         case FWD_IPC_ADDIF:
 177                                         case FWD_IPC_DELIF:
 178                                                 if( strlen(msg.data.network) > 0 )
 179                                                 {
 180                                                         fwd_ipt_delif(h, msg.data.network);
 181
 182                                                         if( msg.type == FWD_IPC_ADDIF )
 183                                                                 fwd_ipt_addif(h, msg.data.network);
 184
 185                                                         fwd_ipc_sendtype(unix_client, FWD_IPC_OK);
 186                                                 }
 187                                                 else
 188                                                 {
 189                                                         fwd_log_err("No network name provided!");
 190                                                         fwd_ipc_sendtype(unix_client, FWD_IPC_ERROR);
 191                                                 }
 192                                                 break;
 193
 194                                         case FWD_IPC_OK:
 195                                         case FWD_IPC_ERROR:
 196                                                 break;
 197                                 }
 198                         }
 199
 200                         fwd_ipc_shutdown(unix_client);
 201                 }
 202
 203
 204                 sleep(1);
 205         }
 206
 207         fwd_delif_all(h);
 208         fwd_ipt_clear_ruleset(h);
 209
 210         close(h->rtnl_socket);
 211         fwd_free_config(h->conf);
 212         fwd_free_ptr(h);
 213
 214         return 0;
 215 }
 216
 217 static void fwd_client_usage(const char *msg)
 218 {
 219         printf(
 220                 "%s\n\n"
 221                 "Usage:\n"
 222                 "  fw flush\n"
 223                 "    Flush all rules in the firewall and reset policy\n\n"
 224                 "  fw build\n"
 225                 "    Rebuild firewall rules\n\n"
 226                 "  fw reload\n"
 227                 "    Reload configuration and rebuild firewall rules\n\n"
 228                 "  fw addif {network}\n"
 229                 "    Add rules for given network\n\n"
 230                 "  fw delif {network}\n"
 231                 "    Remove rules for given network\n\n"
 232                 "", msg
 233         );
 234
 235         exit(1);
 236 }
 237
 238 static int fwd_client_main(int argc, const char *argv[])
 239 {
 240         int unix_server;
 241         struct fwd_ipc_msg msg;
 242         enum fwd_ipc_msgtype type;
 243
 244         if( argc < 2 )
 245                 fwd_client_usage("Command required");
 246
 247         if( (unix_server = fwd_ipc_connect()) < 0 )
 248                 fwd_fatal("Cannot connect to server instance (%m)");
 249
 250
 251         memset(&msg, 0, sizeof(struct fwd_ipc_msg));
 252
 253         if( !strcmp(argv[1], "flush") )
 254                 type = FWD_IPC_FLUSH;
 255
 256         else if( !strcmp(argv[1], "build") )
 257                 type = FWD_IPC_BUILD;
 258
 259         else if( !strcmp(argv[1], "reload") )
 260                 type = FWD_IPC_RELOAD;
 261
 262         else if( !strcmp(argv[1], "addif") || !strcmp(argv[1], "delif") )
 263         {
 264                 if( argc < 3 )
 265                         fwd_client_usage("The command requires a parameter.");
 266
 267                 type = strcmp(argv[1], "addif") ? FWD_IPC_DELIF : FWD_IPC_ADDIF;
 268                 strncpy(msg.data.network, argv[2], sizeof(msg.data.network));
 269         }
 270
 271         else
 272                 fwd_client_usage("Invalid command given.");
 273
 274         msg.type = type;
 275         fwd_ipc_sendmsg(unix_server, &msg, sizeof(struct fwd_ipc_msg));
 276
 277         memset(&msg, 0, sizeof(struct fwd_ipc_msg));
 278
 279         while( fwd_ipc_recvmsg(unix_server, &msg, sizeof(struct fwd_ipc_msg)) == 0 )
 280                 continue;
 281
 282         switch(msg.type)
 283         {
 284                 case FWD_IPC_OK:
 285                         printf("Success\n");
 286                         break;
 287
 288                 case FWD_IPC_ERROR:
 289                         printf("The server reported an error, check logread!\n");
 290                         break;
 291
 292                 default:
 293                         fwd_fatal("Unexpected response type %i", msg.type);
 294         }
 295
 296         fwd_ipc_shutdown(unix_server);
 297
 298         return 0;
 299 }
 300
 301 int main(int argc, const char *argv[])
 302 {
 303         if( strstr(argv[0], "fwd") )
 304                 return fwd_server_main(argc, argv);
 305         else
 306                 return fwd_client_main(argc, argv);
 307 }
 308