release/src/router/iptables/iptables-restore.c

   1 /* Code to restore the iptables state, from file by iptables-save.
   2  * (C) 2000-2002 by Harald Welte <laforge@gnumonks.org>
   3  * based on previous code from Rusty Russell <rusty@linuxcare.com.au>
   4  *
   5  * This code is distributed under the terms of GNU GPL v2
   6  *
   7  * $Id: iptables-restore.c 6828 2007-05-10 15:00:39Z /C=EU/ST=EU/CN=Patrick McHardy/emailAddress=kaber@trash.net $
   8  */
   9
  10 #include <getopt.h>
  11 #include <sys/errno.h>
  12 #include <string.h>
  13 #include <stdio.h>
  14 #include <stdlib.h>
  15 #include "iptables.h"
  16 #include "libiptc/libiptc.h"
  17
  18 #ifdef DEBUG
  19 #define DEBUGP(x, args...) fprintf(stderr, x, ## args)
  20 #else
  21 #define DEBUGP(x, args...)
  22 #endif
  23
  24 static int binary = 0, counters = 0, verbose = 0, noflush = 0;
  25
  26 /* Keeping track of external matches and targets.  */
  27 static struct option options[] = {
  28         { "binary", 0, 0, 'b' },
  29         { "counters", 0, 0, 'c' },
  30         { "verbose", 0, 0, 'v' },
  31         { "test", 0, 0, 't' },
  32         { "help", 0, 0, 'h' },
  33         { "noflush", 0, 0, 'n'},
  34         { "modprobe", 1, 0, 'M'},
  35         { 0 }
  36 };
  37
  38 static void print_usage(const char *name, const char *version) __attribute__((noreturn));
  39
  40 static void print_usage(const char *name, const char *version)
  41 {
  42         fprintf(stderr, "Usage: %s [-b] [-c] [-v] [-t] [-h]\n"
  43                         "          [ --binary ]\n"
  44                         "          [ --counters ]\n"
  45                         "          [ --verbose ]\n"
  46                         "          [ --test ]\n"
  47                         "          [ --help ]\n"
  48                         "          [ --noflush ]\n"
  49                         "          [ --modprobe=<command>]\n", name);
  50
  51         exit(1);
  52 }
  53
  54 iptc_handle_t create_handle(const char *tablename, const char* modprobe )
  55 {
  56         iptc_handle_t handle;
  57
  58         handle = iptc_init(tablename);
  59
  60         if (!handle) {
  61                 /* try to insmod the module if iptc_init failed */
  62                 iptables_insmod("ip_tables", modprobe, 0);
  63                 handle = iptc_init(tablename);
  64         }
  65
  66         if (!handle) {
  67                 exit_error(PARAMETER_PROBLEM, "%s: unable to initialize "
  68                         "table '%s'\n", program_name, tablename);
  69                 exit(1);
  70         }
  71         return handle;
  72 }
  73
  74 static int parse_counters(char *string, struct ipt_counters *ctr)
  75 {
  76         unsigned long long pcnt, bcnt;
  77         int ret;
  78
  79         ret = sscanf(string, "[%llu:%llu]",
  80                      (unsigned long long *)&pcnt,
  81                      (unsigned long long *)&bcnt);
  82         ctr->pcnt = pcnt;
  83         ctr->bcnt = bcnt;
  84         return ret == 2;
  85 }
  86
  87 /* global new argv and argc */
  88 static char *newargv[255];
  89 static int newargc;
  90
  91 /* function adding one argument to newargv, updating newargc
  92  * returns true if argument added, false otherwise */
  93 static int add_argv(char *what) {
  94         DEBUGP("add_argv: %s\n", what);
  95         if (what && ((newargc + 1) < sizeof(newargv)/sizeof(char *))) {
  96                 newargv[newargc] = strdup(what);
  97                 newargc++;
  98                 return 1;
  99         } else
 100                 return 0;
 101 }
 102
 103 static void free_argv(void) {
 104         int i;
 105
 106         for (i = 0; i < newargc; i++)
 107                 free(newargv[i]);
 108 }
 109
 110 #ifdef IPTABLES_MULTI
 111 int
 112 iptables_restore_main(int argc, char *argv[])
 113 #else
 114 int
 115 main(int argc, char *argv[])
 116 #endif
 117 {
 118         iptc_handle_t handle = NULL;
 119         char buffer[10240];
 120         int c;
 121         char curtable[IPT_TABLE_MAXNAMELEN + 1];
 122         FILE *in;
 123         const char *modprobe = 0;
 124         int in_table = 0, testing = 0;
 125
 126         program_name = "iptables-restore";
 127         program_version = IPTABLES_VERSION;
 128         line = 0;
 129
 130         lib_dir = getenv("IPTABLES_LIB_DIR");
 131         if (!lib_dir)
 132                 lib_dir = IPT_LIB_DIR;
 133
 134 #ifdef NO_SHARED_LIBS
 135         init_extensions();
 136 #endif
 137
 138         while ((c = getopt_long(argc, argv, "bcvthnM:", options, NULL)) != -1) {
 139                 switch (c) {
 140                         case 'b':
 141                                 binary = 1;
 142                                 break;
 143                         case 'c':
 144                                 counters = 1;
 145                                 break;
 146                         case 'v':
 147                                 verbose = 1;
 148                                 break;
 149                         case 't':
 150                                 testing = 1;
 151                                 break;
 152                         case 'h':
 153                                 print_usage("iptables-restore",
 154                                             IPTABLES_VERSION);
 155                                 break;
 156                         case 'n':
 157                                 noflush = 1;
 158                                 break;
 159                         case 'M':
 160                                 modprobe = optarg;
 161                                 break;
 162                 }
 163         }
 164
 165         if (optind == argc - 1) {
 166                 in = fopen(argv[optind], "r");
 167                 if (!in) {
 168                         fprintf(stderr, "Can't open %s: %s\n", argv[optind],
 169                                 strerror(errno));
 170                         exit(1);
 171                 }
 172         }
 173         else if (optind < argc) {
 174                 fprintf(stderr, "Unknown arguments found on commandline\n");
 175                 exit(1);
 176         }
 177         else in = stdin;
 178
 179         /* Grab standard input. */
 180         while (fgets(buffer, sizeof(buffer), in)) {
 181                 int ret = 0;
 182
 183                 line++;
 184                 if (buffer[0] == '\n')
 185                         continue;
 186                 else if (buffer[0] == '#') {
 187                         if (verbose)
 188                                 fputs(buffer, stdout);
 189                         continue;
 190                 } else if ((strcmp(buffer, "COMMIT\n") == 0) && (in_table)) {
 191                         if (!testing) {
 192                                 DEBUGP("Calling commit\n");
 193                                 ret = iptc_commit(&handle);
 194                         } else {
 195                                 DEBUGP("Not calling commit, testing\n");
 196                                 ret = 1;
 197                         }
 198                         in_table = 0;
 199                 } else if ((buffer[0] == '*') && (!in_table)) {
 200                         /* New table */
 201                         char *table;
 202
 203                         table = strtok(buffer+1, " \t\n");
 204                         DEBUGP("line %u, table '%s'\n", line, table);
 205                         if (!table) {
 206                                 exit_error(PARAMETER_PROBLEM,
 207                                         "%s: line %u table name invalid\n",
 208                                         program_name, line);
 209                                 exit(1);
 210                         }
 211                         strncpy(curtable, table, IPT_TABLE_MAXNAMELEN);
 212                         curtable[IPT_TABLE_MAXNAMELEN] = '\0';
 213
 214                         if (handle)
 215                                 iptc_free(&handle);
 216
 217                         handle = create_handle(table, modprobe);
 218                         if (noflush == 0) {
 219                                 DEBUGP("Cleaning all chains of table '%s'\n",
 220                                         table);
 221                                 for_each_chain(flush_entries, verbose, 1,
 222                                                 &handle);
 223
 224                                 DEBUGP("Deleting all user-defined chains "
 225                                        "of table '%s'\n", table);
 226                                 for_each_chain(delete_chain, verbose, 0,
 227                                                 &handle) ;
 228                         }
 229
 230                         ret = 1;
 231                         in_table = 1;
 232
 233                 } else if ((buffer[0] == ':') && (in_table)) {
 234                         /* New chain. */
 235                         char *policy, *chain;
 236
 237                         chain = strtok(buffer+1, " \t\n");
 238                         DEBUGP("line %u, chain '%s'\n", line, chain);
 239                         if (!chain) {
 240                                 exit_error(PARAMETER_PROBLEM,
 241                                            "%s: line %u chain name invalid\n",
 242                                            program_name, line);
 243                                 exit(1);
 244                         }
 245
 246                         if (iptc_builtin(chain, handle) <= 0) {
 247                                 if (noflush && iptc_is_chain(chain, handle)) {
 248                                         DEBUGP("Flushing existing user defined chain '%s'\n", chain);
 249                                         if (!iptc_flush_entries(chain, &handle))
 250                                                 exit_error(PARAMETER_PROBLEM,
 251                                                            "error flushing chain "
 252                                                            "'%s':%s\n", chain,
 253                                                            strerror(errno));
 254                                 } else {
 255                                         DEBUGP("Creating new chain '%s'\n", chain);
 256                                         if (!iptc_create_chain(chain, &handle))
 257                                                 exit_error(PARAMETER_PROBLEM,
 258                                                            "error creating chain "
 259                                                            "'%s':%s\n", chain,
 260                                                            strerror(errno));
 261                                 }
 262                         }
 263
 264                         policy = strtok(NULL, " \t\n");
 265                         DEBUGP("line %u, policy '%s'\n", line, policy);
 266                         if (!policy) {
 267                                 exit_error(PARAMETER_PROBLEM,
 268                                            "%s: line %u policy invalid\n",
 269                                            program_name, line);
 270                                 exit(1);
 271                         }
 272
 273                         if (strcmp(policy, "-") != 0) {
 274                                 struct ipt_counters count;
 275
 276                                 if (counters) {
 277                                         char *ctrs;
 278                                         ctrs = strtok(NULL, " \t\n");
 279
 280                                         if (!ctrs || !parse_counters(ctrs, &count))
 281                                                 exit_error(PARAMETER_PROBLEM,
 282                                                            "invalid policy counters "
 283                                                            "for chain '%s'\n", chain);
 284
 285                                 } else {
 286                                         memset(&count, 0,
 287                                                sizeof(struct ipt_counters));
 288                                 }
 289
 290                                 DEBUGP("Setting policy of chain %s to %s\n",
 291                                         chain, policy);
 292
 293                                 if (!iptc_set_policy(chain, policy, &count,
 294                                                      &handle))
 295                                         exit_error(OTHER_PROBLEM,
 296                                                 "Can't set policy `%s'"
 297                                                 " on `%s' line %u: %s\n",
 298                                                 chain, policy, line,
 299                                                 iptc_strerror(errno));
 300                         }
 301
 302                         ret = 1;
 303
 304                 } else if (in_table) {
 305                         int a;
 306                         char *ptr = buffer;
 307                         char *pcnt = NULL;
 308                         char *bcnt = NULL;
 309                         char *parsestart;
 310
 311                         /* the parser */
 312                         char *curchar;
 313                         int quote_open, escaped;
 314                         size_t param_len;
 315
 316                         /* reset the newargv */
 317                         newargc = 0;
 318
 319                         if (buffer[0] == '[') {
 320                                 /* we have counters in our input */
 321                                 ptr = strchr(buffer, ']');
 322                                 if (!ptr)
 323                                         exit_error(PARAMETER_PROBLEM,
 324                                                    "Bad line %u: need ]\n",
 325                                                    line);
 326
 327                                 pcnt = strtok(buffer+1, ":");
 328                                 if (!pcnt)
 329                                         exit_error(PARAMETER_PROBLEM,
 330                                                    "Bad line %u: need :\n",
 331                                                    line);
 332
 333                                 bcnt = strtok(NULL, "]");
 334                                 if (!bcnt)
 335                                         exit_error(PARAMETER_PROBLEM,
 336                                                    "Bad line %u: need ]\n",
 337                                                    line);
 338
 339                                 /* start command parsing after counter */
 340                                 parsestart = ptr + 1;
 341                         } else {
 342                                 /* start command parsing at start of line */
 343                                 parsestart = buffer;
 344                         }
 345
 346                         add_argv(argv[0]);
 347                         add_argv("-t");
 348                         add_argv((char *) &curtable);
 349
 350                         if (counters && pcnt && bcnt) {
 351                                 add_argv("--set-counters");
 352                                 add_argv((char *) pcnt);
 353                                 add_argv((char *) bcnt);
 354                         }
 355
 356                         /* After fighting with strtok enough, here's now
 357                          * a 'real' parser. According to Rusty I'm now no
 358                          * longer a real hacker, but I can live with that */
 359
 360                         quote_open = 0;
 361                         escaped = 0;
 362                         param_len = 0;
 363
 364                         for (curchar = parsestart; *curchar; curchar++) {
 365                                 char param_buffer[1024];
 366
 367                                 if (quote_open) {
 368                                         if (escaped) {
 369                                                 param_buffer[param_len++] = *curchar;
 370                                                 escaped = 0;
 371                                                 continue;
 372                                         } else if (*curchar == '\\') {
 373                                                 escaped = 1;
 374                                                 continue;
 375                                         } else if (*curchar == '"') {
 376                                                 quote_open = 0;
 377                                                 *curchar = ' ';
 378                                         } else {
 379                                                 param_buffer[param_len++] = *curchar;
 380                                                 continue;
 381                                         }
 382                                 } else {
 383                                         if (*curchar == '"') {
 384                                                 quote_open = 1;
 385                                                 continue;
 386                                         }
 387                                 }
 388
 389                                 if (*curchar == ' '
 390                                     || *curchar == '\t'
 391                                     || * curchar == '\n') {
 392                                         if (!param_len) {
 393                                                 /* two spaces? */
 394                                                 continue;
 395                                         }
 396
 397                                         param_buffer[param_len] = '\0';
 398
 399                                         /* check if table name specified */
 400                                         if (!strncmp(param_buffer, "-t", 2)
 401                                             || !strncmp(param_buffer, "--table", 8)) {
 402                                                 exit_error(PARAMETER_PROBLEM,
 403                                                    "Line %u seems to have a "
 404                                                    "-t table option.\n", line);
 405                                                 exit(1);
 406                                         }
 407
 408                                         add_argv(param_buffer);
 409                                         param_len = 0;
 410                                 } else {
 411                                         /* regular character, copy to buffer */
 412                                         param_buffer[param_len++] = *curchar;
 413
 414                                         if (param_len >= sizeof(param_buffer))
 415                                                 exit_error(PARAMETER_PROBLEM,
 416                                                    "Parameter too long!");
 417                                 }
 418                         }
 419
 420                         DEBUGP("calling do_command(%u, argv, &%s, handle):\n",
 421                                 newargc, curtable);
 422
 423                         for (a = 0; a < newargc; a++)
 424                                 DEBUGP("argv[%u]: %s\n", a, newargv[a]);
 425
 426                         ret = do_command(newargc, newargv,
 427                                          &newargv[2], &handle);
 428
 429                         free_argv();
 430                         fflush(stdout);
 431                 }
 432                 if (!ret) {
 433                         fprintf(stderr, "%s: line %u failed\n",
 434                                         program_name, line);
 435                         exit(1);
 436                 }
 437         }
 438         if (in_table) {
 439                 fprintf(stderr, "%s: COMMIT expected at line %u\n",
 440                                 program_name, line + 1);
 441                 exit(1);
 442         }
 443
 444         return 0;
 445 }