release/src/router/iptables/extensions/libipt_SET.c

   1 /* Copyright (C) 2000-2002 Joakim Axelsson <gozem@linux.nu>
   2  *                         Patrick Schaaf <bof@bof.de>
   3  *                         Martin Josefsson <gandalf@wlug.westbo.se>
   4  * Copyright (C) 2003-2004 Jozsef Kadlecsik <kadlec@blackhole.kfki.hu>
   5  *
   6  * This program is free software; you can redistribute it and/or modify
   7  * it under the terms of the GNU General Public License version 2 as
   8  * published by the Free Software Foundation.
   9  */
  10
  11 /* Shared library add-on to iptables to add IP set mangling target. */
  12 #include <stdio.h>
  13 #include <netdb.h>
  14 #include <string.h>
  15 #include <stdlib.h>
  16 #include <getopt.h>
  17 #include <ctype.h>
  18
  19 #include <iptables.h>
  20 #include <linux/netfilter_ipv4/ip_tables.h>
  21 #include <linux/netfilter_ipv4/ip_set.h>
  22 #include <linux/netfilter_ipv4/ipt_set.h>
  23 #include "libipt_set.h"
  24
  25 /* Function which prints out usage message. */
  26 static void help(void)
  27 {
  28         printf("SET v%s options:\n"
  29                " --add-set name flags\n"
  30                " --del-set name flags\n"
  31                "                add/del src/dst IP/port from/to named sets,\n"
  32                "                where flags are the comma separated list of\n"
  33                "                'src' and 'dst'.\n"
  34                "\n", IPTABLES_VERSION);
  35 }
  36
  37 static struct option opts[] = {
  38         {"add-set",   1, 0, '1'},
  39         {"del-set",   1, 0, '2'},
  40         {0}
  41 };
  42
  43 /* Initialize the target. */
  44 static void init(struct ipt_entry_target *target, unsigned int *nfcache)
  45 {
  46         struct ipt_set_info_target *info =
  47             (struct ipt_set_info_target *) target->data;
  48
  49         memset(info, 0, sizeof(struct ipt_set_info_target));
  50         info->add_set.index =
  51         info->del_set.index = IP_SET_INVALID_ID;
  52
  53 }
  54
  55 static void
  56 parse_target(char **argv, int invert, unsigned int *flags,
  57              struct ipt_set_info *info, const char *what)
  58 {
  59         if (info->flags[0])
  60                 exit_error(PARAMETER_PROBLEM,
  61                            "--%s can be specified only once", what);
  62
  63         if (check_inverse(optarg, &invert, NULL, 0))
  64                 exit_error(PARAMETER_PROBLEM,
  65                            "Unexpected `!' after --%s", what);
  66
  67         if (!argv[optind]
  68             || argv[optind][0] == '-' || argv[optind][0] == '!')
  69                 exit_error(PARAMETER_PROBLEM,
  70                            "--%s requires two args.", what);
  71
  72         if (strlen(argv[optind-1]) > IP_SET_MAXNAMELEN - 1)
  73                 exit_error(PARAMETER_PROBLEM,
  74                            "setname `%s' too long, max %d characters.",
  75                            argv[optind-1], IP_SET_MAXNAMELEN - 1);
  76
  77         get_set_byname(argv[optind - 1], info);
  78         parse_bindings(argv[optind], info);
  79         optind++;
  80
  81         *flags = 1;
  82 }
  83
  84 /* Function which parses command options; returns true if it
  85    ate an option */
  86 static int
  87 parse(int c, char **argv, int invert, unsigned int *flags,
  88       const struct ipt_entry *entry, struct ipt_entry_target **target)
  89 {
  90         struct ipt_set_info_target *myinfo =
  91             (struct ipt_set_info_target *) (*target)->data;
  92
  93         switch (c) {
  94         case '1':               /* --add-set <set> <flags> */
  95                 parse_target(argv, invert, flags,
  96                              &myinfo->add_set, "add-set");
  97                 break;
  98         case '2':               /* --del-set <set>[:<flags>] <flags> */
  99                 parse_target(argv, invert, flags,
 100                              &myinfo->del_set, "del-set");
 101                 break;
 102
 103         default:
 104                 return 0;
 105         }
 106         return 1;
 107 }
 108
 109 /* Final check; must specify at least one. */
 110 static void final_check(unsigned int flags)
 111 {
 112         if (!flags)
 113                 exit_error(PARAMETER_PROBLEM,
 114                            "You must specify either `--add-set' or `--del-set'");
 115 }
 116
 117 static void
 118 print_target(const char *prefix, const struct ipt_set_info *info)
 119 {
 120         int i;
 121         char setname[IP_SET_MAXNAMELEN];
 122
 123         if (info->index == IP_SET_INVALID_ID)
 124                 return;
 125         get_set_byid(setname, info->index);
 126         printf("%s %s", prefix, setname);
 127         for (i = 0; i < IP_SET_MAX_BINDINGS; i++) {
 128                 if (!info->flags[i])
 129                         break;
 130                 printf("%s%s",
 131                        i == 0 ? " " : ",",
 132                        info->flags[i] & IPSET_SRC ? "src" : "dst");
 133         }
 134         printf(" ");
 135 }
 136
 137 /* Prints out the targinfo. */
 138 static void
 139 print(const struct ipt_ip *ip,
 140       const struct ipt_entry_target *target, int numeric)
 141 {
 142         struct ipt_set_info_target *info =
 143             (struct ipt_set_info_target *) target->data;
 144
 145         print_target("add-set", &info->add_set);
 146         print_target("del-set", &info->del_set);
 147 }
 148
 149 /* Saves the union ipt_targinfo in parsable form to stdout. */
 150 static void
 151 save(const struct ipt_ip *ip, const struct ipt_entry_target *target)
 152 {
 153         struct ipt_set_info_target *info =
 154             (struct ipt_set_info_target *) target->data;
 155
 156         print_target("--add-set", &info->add_set);
 157         print_target("--del-set", &info->del_set);
 158 }
 159
 160 static
 161 struct iptables_target ipt_set_target
 162 = {
 163         .name           = "SET",
 164         .version        = IPTABLES_VERSION,
 165         .size           = IPT_ALIGN(sizeof(struct ipt_set_info_target)),
 166         .userspacesize  = IPT_ALIGN(sizeof(struct ipt_set_info_target)),
 167         .help           = &help,
 168         .init           = &init,
 169         .parse          = &parse,
 170         .final_check    = &final_check,
 171         .print          = &print,
 172         .save           = &save,
 173         .extra_opts     = opts
 174 };
 175
 176 void _init(void)
 177 {
 178         register_target(&ipt_set_target);
 179 }