ip6tables-restore.c

   1 /* Code to restore the iptables state, from file by ip6tables-save.
   2  * Author:  Andras Kis-Szabo <kisza@sch.bme.hu>
   3  *
   4  * based on iptables-restore
   5  * Authors:
   6  *      Harald Welte <laforge@gnumonks.org>
   7  *      Rusty Russell <rusty@linuxcare.com.au>
   8  * This code is distributed under the terms of GNU GPL v2
   9  *
  10  * $Id: ip6tables-restore.c 6828 2007-05-10 15:00:39Z /C=EU/ST=EU/CN=Patrick McHardy/emailAddress=kaber@trash.net $
  11  */
  12
  13 #include <getopt.h>
  14 #include <sys/errno.h>
  15 #include <string.h>
  16 #include <stdio.h>
  17 #include <stdlib.h>
  18 #include "ip6tables.h"
  19 #include "libiptc/libip6tc.h"
  20
  21 #ifdef DEBUG
  22 #define DEBUGP(x, args...) fprintf(stderr, x, ## args)
  23 #else
  24 #define DEBUGP(x, args...)
  25 #endif
  26
  27 static int binary = 0, counters = 0, verbose = 0, noflush = 0;
  28
  29 /* Keeping track of external matches and targets.  */
  30 static struct option options[] = {
  31         { "binary", 0, 0, 'b' },
  32         { "counters", 0, 0, 'c' },
  33         { "verbose", 0, 0, 'v' },
  34         { "test", 0, 0, 't' },
  35         { "help", 0, 0, 'h' },
  36         { "noflush", 0, 0, 'n'},
  37         { "modprobe", 1, 0, 'M'},
  38         { 0 }
  39 };
  40
  41 static void print_usage(const char *name, const char *version) __attribute__((noreturn));
  42
  43 static void print_usage(const char *name, const char *version)
  44 {
  45         fprintf(stderr, "Usage: %s [-b] [-c] [-v] [-t] [-h]\n"
  46                         "          [ --binary ]\n"
  47                         "          [ --counters ]\n"
  48                         "          [ --verbose ]\n"
  49                         "          [ --test ]\n"
  50                         "          [ --help ]\n"
  51                         "          [ --noflush ]\n"
  52                         "          [ --modprobe=<command>]\n", name);
  53
  54         exit(1);
  55 }
  56
  57 ip6tc_handle_t create_handle(const char *tablename, const char* modprobe)
  58 {
  59         ip6tc_handle_t handle;
  60
  61         handle = ip6tc_init(tablename);
  62
  63         if (!handle) {
  64                 /* try to insmod the module if iptc_init failed */
  65                 ip6tables_insmod("ip6_tables", modprobe, 0);
  66                 handle = ip6tc_init(tablename);
  67         }
  68
  69         if (!handle) {
  70                 exit_error(PARAMETER_PROBLEM, "%s: unable to initialize "
  71                         "table '%s'\n", program_name, tablename);
  72                 exit(1);
  73         }
  74         return handle;
  75 }
  76
  77 static int parse_counters(char *string, struct ip6t_counters *ctr)
  78 {
  79         return (sscanf(string, "[%llu:%llu]", (unsigned long long *)&ctr->pcnt, (unsigned long long *)&ctr->bcnt) == 2);
  80 }
  81
  82 /* global new argv and argc */
  83 static char *newargv[255];
  84 static int newargc;
  85
  86 /* function adding one argument to newargv, updating newargc
  87  * returns true if argument added, false otherwise */
  88 static int add_argv(char *what) {
  89         DEBUGP("add_argv: %s\n", what);
  90         if (what && ((newargc + 1) < sizeof(newargv)/sizeof(char *))) {
  91                 newargv[newargc] = strdup(what);
  92                 newargc++;
  93                 return 1;
  94         } else
  95                 return 0;
  96 }
  97
  98 static void free_argv(void) {
  99         int i;
 100
 101         for (i = 0; i < newargc; i++)
 102                 free(newargv[i]);
 103 }
 104
 105 int main(int argc, char *argv[])
 106 {
 107         ip6tc_handle_t handle = NULL;
 108         char buffer[10240];
 109         int c;
 110         char curtable[IP6T_TABLE_MAXNAMELEN + 1];
 111         FILE *in;
 112         const char *modprobe = 0;
 113         int in_table = 0, testing = 0;
 114
 115         program_name = "ip6tables-restore";
 116         program_version = IPTABLES_VERSION;
 117         line = 0;
 118
 119         lib_dir = getenv("IP6TABLES_LIB_DIR");
 120         if (!lib_dir)
 121                 lib_dir = IP6T_LIB_DIR;
 122
 123 #ifdef NO_SHARED_LIBS
 124         init_extensions();
 125 #endif
 126
 127         while ((c = getopt_long(argc, argv, "bcvthnM:", options, NULL)) != -1) {
 128                 switch (c) {
 129                         case 'b':
 130                                 binary = 1;
 131                                 break;
 132                         case 'c':
 133                                 counters = 1;
 134                                 break;
 135                         case 'v':
 136                                 verbose = 1;
 137                                 break;
 138                         case 't':
 139                                 testing = 1;
 140                                 break;
 141                         case 'h':
 142                                 print_usage("ip6tables-restore",
 143                                             IPTABLES_VERSION);
 144                                 break;
 145                         case 'n':
 146                                 noflush = 1;
 147                                 break;
 148                         case 'M':
 149                                 modprobe = optarg;
 150                                 break;
 151                 }
 152         }
 153
 154         if (optind == argc - 1) {
 155                 in = fopen(argv[optind], "r");
 156                 if (!in) {
 157                         fprintf(stderr, "Can't open %s: %s\n", argv[optind],
 158                                 strerror(errno));
 159                         exit(1);
 160                 }
 161         }
 162         else if (optind < argc) {
 163                 fprintf(stderr, "Unknown arguments found on commandline\n");
 164                 exit(1);
 165         }
 166         else in = stdin;
 167
 168         /* Grab standard input. */
 169         while (fgets(buffer, sizeof(buffer), in)) {
 170                 int ret = 0;
 171
 172                 line++;
 173                 if (buffer[0] == '\n')
 174                         continue;
 175                 else if (buffer[0] == '#') {
 176                         if (verbose)
 177                                 fputs(buffer, stdout);
 178                         continue;
 179                 } else if ((strcmp(buffer, "COMMIT\n") == 0) && (in_table)) {
 180                         if (!testing) {
 181                                 DEBUGP("Calling commit\n");
 182                                 ret = ip6tc_commit(&handle);
 183                         } else {
 184                                 DEBUGP("Not calling commit, testing\n");
 185                                 ret = 1;
 186                         }
 187                         in_table = 0;
 188                 } else if ((buffer[0] == '*') && (!in_table)) {
 189                         /* New table */
 190                         char *table;
 191
 192                         table = strtok(buffer+1, " \t\n");
 193                         DEBUGP("line %u, table '%s'\n", line, table);
 194                         if (!table) {
 195                                 exit_error(PARAMETER_PROBLEM,
 196                                         "%s: line %u table name invalid\n",
 197                                         program_name, line);
 198                                 exit(1);
 199                         }
 200                         strncpy(curtable, table, IP6T_TABLE_MAXNAMELEN);
 201                         curtable[IP6T_TABLE_MAXNAMELEN] = '\0';
 202
 203                         if (handle)
 204                                 ip6tc_free(&handle);
 205
 206                         handle = create_handle(table, modprobe);
 207                         if (noflush == 0) {
 208                                 DEBUGP("Cleaning all chains of table '%s'\n",
 209                                         table);
 210                                 for_each_chain(flush_entries, verbose, 1,
 211                                                 &handle);
 212
 213                                 DEBUGP("Deleting all user-defined chains "
 214                                        "of table '%s'\n", table);
 215                                 for_each_chain(delete_chain, verbose, 0,
 216                                                 &handle) ;
 217                         }
 218
 219                         ret = 1;
 220                         in_table = 1;
 221
 222                 } else if ((buffer[0] == ':') && (in_table)) {
 223                         /* New chain. */
 224                         char *policy, *chain;
 225
 226                         chain = strtok(buffer+1, " \t\n");
 227                         DEBUGP("line %u, chain '%s'\n", line, chain);
 228                         if (!chain) {
 229                                 exit_error(PARAMETER_PROBLEM,
 230                                            "%s: line %u chain name invalid\n",
 231                                            program_name, line);
 232                                 exit(1);
 233                         }
 234
 235                         if (ip6tc_builtin(chain, handle) <= 0) {
 236                                 if (noflush && ip6tc_is_chain(chain, handle)) {
 237                                         DEBUGP("Flushing existing user defined chain '%s'\n", chain);
 238                                         if (!ip6tc_flush_entries(chain, &handle))
 239                                                 exit_error(PARAMETER_PROBLEM,
 240                                                            "error flushing chain "
 241                                                            "'%s':%s\n", chain,
 242                                                            strerror(errno));
 243                                 } else {
 244                                         DEBUGP("Creating new chain '%s'\n", chain);
 245                                         if (!ip6tc_create_chain(chain, &handle))
 246                                                 exit_error(PARAMETER_PROBLEM,
 247                                                            "error creating chain "
 248                                                            "'%s':%s\n", chain,
 249                                                            strerror(errno));
 250                                 }
 251                         }
 252
 253                         policy = strtok(NULL, " \t\n");
 254                         DEBUGP("line %u, policy '%s'\n", line, policy);
 255                         if (!policy) {
 256                                 exit_error(PARAMETER_PROBLEM,
 257                                            "%s: line %u policy invalid\n",
 258                                            program_name, line);
 259                                 exit(1);
 260                         }
 261
 262                         if (strcmp(policy, "-") != 0) {
 263                                 struct ip6t_counters count;
 264
 265                                 if (counters) {
 266                                         char *ctrs;
 267                                         ctrs = strtok(NULL, " \t\n");
 268
 269                                         if (!ctrs || !parse_counters(ctrs, &count))
 270                                                 exit_error(PARAMETER_PROBLEM,
 271                                                           "invalid policy counters "
 272                                                           "for chain '%s'\n", chain);
 273
 274                                 } else {
 275                                         memset(&count, 0,
 276                                                sizeof(struct ip6t_counters));
 277                                 }
 278
 279                                 DEBUGP("Setting policy of chain %s to %s\n",
 280                                         chain, policy);
 281
 282                                 if (!ip6tc_set_policy(chain, policy, &count,
 283                                                      &handle))
 284                                         exit_error(OTHER_PROBLEM,
 285                                                 "Can't set policy `%s'"
 286                                                 " on `%s' line %u: %s\n",
 287                                                 chain, policy, line,
 288                                                 ip6tc_strerror(errno));
 289                         }
 290
 291                         ret = 1;
 292
 293                 } else if (in_table) {
 294                         int a;
 295                         char *ptr = buffer;
 296                         char *pcnt = NULL;
 297                         char *bcnt = NULL;
 298                         char *parsestart;
 299
 300                         /* the parser */
 301                         char *param_start, *curchar;
 302                         int quote_open;
 303
 304                         /* reset the newargv */
 305                         newargc = 0;
 306
 307                         if (buffer[0] == '[') {
 308                                 /* we have counters in our input */
 309                                 ptr = strchr(buffer, ']');
 310                                 if (!ptr)
 311                                         exit_error(PARAMETER_PROBLEM,
 312                                                    "Bad line %u: need ]\n",
 313                                                    line);
 314
 315                                 pcnt = strtok(buffer+1, ":");
 316                                 if (!pcnt)
 317                                         exit_error(PARAMETER_PROBLEM,
 318                                                    "Bad line %u: need :\n",
 319                                                    line);
 320
 321                                 bcnt = strtok(NULL, "]");
 322                                 if (!bcnt)
 323                                         exit_error(PARAMETER_PROBLEM,
 324                                                    "Bad line %u: need ]\n",
 325                                                    line);
 326
 327                                 /* start command parsing after counter */
 328                                 parsestart = ptr + 1;
 329                         } else {
 330                                 /* start command parsing at start of line */
 331                                 parsestart = buffer;
 332                         }
 333
 334                         add_argv(argv[0]);
 335                         add_argv("-t");
 336                         add_argv((char *) &curtable);
 337
 338                         if (counters && pcnt && bcnt) {
 339                                 add_argv("--set-counters");
 340                                 add_argv((char *) pcnt);
 341                                 add_argv((char *) bcnt);
 342                         }
 343
 344                         /* After fighting with strtok enough, here's now
 345                          * a 'real' parser. According to Rusty I'm now no
 346                          * longer a real hacker, but I can live with that */
 347
 348                         quote_open = 0;
 349                         param_start = parsestart;
 350
 351                         for (curchar = parsestart; *curchar; curchar++) {
 352                                 if (*curchar == '"') {
 353                                         /* quote_open cannot be true if there
 354                                          * was no previous character.  Thus,
 355                                          * curchar-1 has to be within bounds */
 356                                         if (quote_open &&
 357                                             *(curchar-1) != '\\') {
 358                                                 quote_open = 0;
 359                                                 *curchar = ' ';
 360                                         } else {
 361                                                 quote_open = 1;
 362                                                 param_start++;
 363                                         }
 364                                 }
 365                                 if (*curchar == ' '
 366                                     || *curchar == '\t'
 367                                     || * curchar == '\n') {
 368                                         char param_buffer[1024];
 369                                         int param_len = curchar-param_start;
 370
 371                                         if (quote_open)
 372                                                 continue;
 373
 374                                         if (!param_len) {
 375                                                 /* two spaces? */
 376                                                 param_start++;
 377                                                 continue;
 378                                         }
 379
 380                                         /* end of one parameter */
 381                                         strncpy(param_buffer, param_start,
 382                                                 param_len);
 383                                         *(param_buffer+param_len) = '\0';
 384
 385                                         /* check if table name specified */
 386                                         if (!strncmp(param_buffer, "-t", 3)
 387                                             || !strncmp(param_buffer, "--table", 8)) {
 388                                                 exit_error(PARAMETER_PROBLEM,
 389                                                    "Line %u seems to have a "
 390                                                    "-t table option.\n", line);
 391                                                 exit(1);
 392                                         }
 393
 394                                         add_argv(param_buffer);
 395                                         param_start += param_len + 1;
 396                                 } else {
 397                                         /* regular character, skip */
 398                                 }
 399                         }
 400
 401                         DEBUGP("calling do_command6(%u, argv, &%s, handle):\n",
 402                                 newargc, curtable);
 403
 404                         for (a = 0; a < newargc; a++)
 405                                 DEBUGP("argv[%u]: %s\n", a, newargv[a]);
 406
 407                         ret = do_command6(newargc, newargv,
 408                                          &newargv[2], &handle);
 409
 410                         free_argv();
 411                 }
 412                 if (!ret) {
 413                         fprintf(stderr, "%s: line %u failed\n",
 414                                         program_name, line);
 415                         exit(1);
 416                 }
 417         }
 418         if (in_table) {
 419                 fprintf(stderr, "%s: COMMIT expected at line %u\n",
 420                                 program_name, line + 1);
 421                 exit(1);
 422         }
 423
 424         return 0;
 425 }