ebtables-restore.c

   1 /*
   2  * ebtables-restore.c, October 2005
   3  *
   4  * Author: Bart De Schuymer
   5  *
   6  * This program is free software; you can redistribute it and/or
   7  * modify it under the terms of the GNU General Public License as
   8  * published by the Free Software Foundation; either version 2 of the
   9  * License, or (at your option) any later version.
  10  *
  11  * This program is distributed in the hope that it will be useful, but
  12  * WITHOUT ANY WARRANTY; without even the implied warranty of
  13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  14  * General Public License for more details.
  15  *
  16  * You should have received a copy of the GNU General Public License
  17  * along with this program; if not, write to the Free Software
  18  * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
  19  */
  20 #include <stdio.h>
  21 #include <stdlib.h>
  22 #include <string.h>
  23 #include <errno.h>
  24 #include <unistd.h>
  25 #include <getopt.h>
  26 #include "include/ebtables_u.h"
  27
  28 static const struct option options[] = {
  29         {.name = "noflush", .has_arg = 0, .val = 'n'},
  30         { 0 }
  31 };
  32
  33 static struct ebt_u_replace replace[3];
  34 void ebt_early_init_once();
  35
  36 #define OPT_KERNELDATA  0x800 /* Also defined in ebtables.c */
  37
  38 static void print_usage()
  39 {
  40         fprintf(stderr, "Usage: ebtables-restore [ --noflush ]\n");
  41         exit(1);
  42 }
  43
  44 static void copy_table_names()
  45 {
  46         strcpy(replace[0].name, "filter");
  47         strcpy(replace[1].name, "nat");
  48         strcpy(replace[2].name, "broute");
  49 }
  50
  51 #define ebtrest_print_error(format, args...) do {fprintf(stderr, "ebtables-restore: "\
  52                                              "line %d: "format".\n", line, ##args); exit(-1);} while (0)
  53 int main(int argc_, char *argv_[])
  54 {
  55         char *argv[EBTD_ARGC_MAX], cmdline[EBTD_CMDLINE_MAXLN];
  56         int i, offset, quotemode = 0, argc, table_nr = -1, line = 0, whitespace, c, flush = 1;
  57         char ebtables_str[] = "ebtables";
  58
  59         while ((c = getopt_long(argc_, argv_, "n", options, NULL)) != -1) {
  60                 switch(c) {
  61                         case 'n':
  62                                 flush = 0;
  63                                 break;
  64                         default:
  65                                 print_usage();
  66                                 break;
  67                 }
  68         }
  69
  70         ebt_silent = 0;
  71         copy_table_names();
  72         ebt_early_init_once();
  73         argv[0] = ebtables_str;
  74
  75         while (fgets(cmdline, EBTD_CMDLINE_MAXLN, stdin)) {
  76                 line++;
  77                 if (*cmdline == '#' || *cmdline == '\n')
  78                         continue;
  79                 *strchr(cmdline, '\n') = '\0';
  80                 if (*cmdline == '*') {
  81                         if (table_nr != -1) {
  82                                 ebt_deliver_table(&replace[table_nr]);
  83                                 ebt_deliver_counters(&replace[table_nr]);
  84                         }
  85                         for (i = 0; i < 3; i++)
  86                                 if (!strcmp(replace[i].name, cmdline+1))
  87                                         break;
  88                         if (i == 3)
  89                                 ebtrest_print_error("table '%s' was not recognized", cmdline+1);
  90                         table_nr = i;
  91                         replace[table_nr].command = 11;
  92                         ebt_get_kernel_table(&replace[table_nr], flush);
  93                         replace[table_nr].command = 0;
  94                         replace[table_nr].flags = OPT_KERNELDATA; /* Prevent do_command from initialising replace */
  95                         continue;
  96                 } else if (table_nr == -1)
  97                         ebtrest_print_error("no table specified");
  98                 if (*cmdline == ':') {
  99                         int policy, chain_nr;
 100                         char *ch;
 101
 102                         if (!(ch = strchr(cmdline, ' ')))
 103                                 ebtrest_print_error("no policy specified");
 104                         *ch = '\0';
 105                         for (i = 0; i < NUM_STANDARD_TARGETS; i++)
 106                                 if (!strcmp(ch+1, ebt_standard_targets[i])) {
 107                                         policy = -i -1;
 108                                         if (policy == EBT_CONTINUE)
 109                                                 i = NUM_STANDARD_TARGETS;
 110                                         break;
 111                                 }
 112                         if (i == NUM_STANDARD_TARGETS)
 113                                 ebtrest_print_error("invalid policy specified");
 114                         /* No need to check chain name for consistency, since
 115                          * we're supposed to be reading an automatically generated
 116                          * file. */
 117                         if ((chain_nr = ebt_get_chainnr(&replace[table_nr], cmdline+1)) == -1)
 118                                 ebt_new_chain(&replace[table_nr], cmdline+1, policy);
 119                         else
 120                                 replace[table_nr].chains[chain_nr]->policy = policy;
 121                         continue;
 122                 }
 123                 argv[1] = cmdline;
 124                 offset = whitespace = 0;
 125                 argc = 2;
 126                 while (cmdline[offset] != '\0') {
 127                         if (cmdline[offset] == '\"') {
 128                                 whitespace = 0;
 129                                 quotemode ^= 1;
 130                                 if (quotemode)
 131                                         argv[argc++] = &cmdline[offset+1];
 132                                 else if (cmdline[offset+1] != ' ' && cmdline[offset+1] != '\0')
 133                                         ebtrest_print_error("syntax error at \"");
 134                                 cmdline[offset] = '\0';
 135                         } else if (!quotemode && cmdline[offset] == ' ') {
 136                                 whitespace = 1;
 137                                 cmdline[offset] = '\0';
 138                         } else if (whitespace == 1) {
 139                                 argv[argc++] = &cmdline[offset];
 140                                 whitespace = 0;
 141                         }
 142                         offset++;
 143                 }
 144                 if (quotemode)
 145                         ebtrest_print_error("wrong use of '\"'");
 146                 optind = 0; /* Setting optind = 1 causes serious annoyances */
 147                 do_command(argc, argv, EXEC_STYLE_DAEMON, &replace[table_nr]);
 148                 ebt_reinit_extensions();
 149         }
 150
 151         if (table_nr != -1) {
 152                 ebt_deliver_table(&replace[table_nr]);
 153                 ebt_deliver_counters(&replace[table_nr]);
 154         }
 155         return 0;
 156 }