extensions/libxt_NFQUEUE.c

   1 /* Shared library add-on to iptables for NFQ
   2  *
   3  * (C) 2005 by Harald Welte <laforge@netfilter.org>
   4  *
   5  * This program is distributed under the terms of GNU GPL v2, 1991
   6  *
   7  */
   8 #include <stdio.h>
   9 #include <string.h>
  10 #include <stdlib.h>
  11 #include <getopt.h>
  12
  13 #include <xtables.h>
  14 #include <linux/netfilter/x_tables.h>
  15 #include <linux/netfilter/xt_NFQUEUE.h>
  16
  17 static void NFQUEUE_help(void)
  18 {
  19         printf(
  20 "NFQUEUE target options\n"
  21 "  --queue-num value            Send packet to QUEUE number <value>.\n"
  22 "                               Valid queue numbers are 0-65535\n"
  23 );
  24 }
  25
  26 static const struct option NFQUEUE_opts[] = {
  27         { "queue-num", 1, NULL, 'F' },
  28         { .name = NULL }
  29 };
  30
  31 static void
  32 parse_num(const char *s, struct xt_NFQ_info *tinfo)
  33 {
  34         unsigned int num;
  35
  36         if (!xtables_strtoui(s, NULL, &num, 0, UINT16_MAX))
  37                 xtables_error(PARAMETER_PROBLEM,
  38                            "Invalid queue number `%s'\n", s);
  39
  40         tinfo->queuenum = num & 0xffff;
  41 }
  42
  43 static int
  44 NFQUEUE_parse(int c, char **argv, int invert, unsigned int *flags,
  45               const void *entry, struct xt_entry_target **target)
  46 {
  47         struct xt_NFQ_info *tinfo
  48                 = (struct xt_NFQ_info *)(*target)->data;
  49
  50         switch (c) {
  51         case 'F':
  52                 if (*flags)
  53                         xtables_error(PARAMETER_PROBLEM, "NFQUEUE target: "
  54                                    "Only use --queue-num ONCE!");
  55                 parse_num(optarg, tinfo);
  56                 break;
  57         default:
  58                 return 0;
  59         }
  60
  61         return 1;
  62 }
  63
  64 static void NFQUEUE_print(const void *ip,
  65                           const struct xt_entry_target *target, int numeric)
  66 {
  67         const struct xt_NFQ_info *tinfo =
  68                 (const struct xt_NFQ_info *)target->data;
  69         printf("NFQUEUE num %u", tinfo->queuenum);
  70 }
  71
  72 static void NFQUEUE_save(const void *ip, const struct xt_entry_target *target)
  73 {
  74         const struct xt_NFQ_info *tinfo =
  75                 (const struct xt_NFQ_info *)target->data;
  76
  77         printf("--queue-num %u ", tinfo->queuenum);
  78 }
  79
  80 static struct xtables_target nfqueue_target = {
  81         .family         = NFPROTO_IPV4,
  82         .name           = "NFQUEUE",
  83         .version        = XTABLES_VERSION,
  84         .size           = XT_ALIGN(sizeof(struct xt_NFQ_info)),
  85         .userspacesize  = XT_ALIGN(sizeof(struct xt_NFQ_info)),
  86         .help           = NFQUEUE_help,
  87         .parse          = NFQUEUE_parse,
  88         .print          = NFQUEUE_print,
  89         .save           = NFQUEUE_save,
  90         .extra_opts     = NFQUEUE_opts
  91 };
  92
  93 static struct xtables_target nfqueue_target6 = {
  94         .family         = NFPROTO_IPV6,
  95         .name           = "NFQUEUE",
  96         .version        = XTABLES_VERSION,
  97         .size           = XT_ALIGN(sizeof(struct xt_NFQ_info)),
  98         .userspacesize  = XT_ALIGN(sizeof(struct xt_NFQ_info)),
  99         .help           = NFQUEUE_help,
 100         .parse          = NFQUEUE_parse,
 101         .print          = NFQUEUE_print,
 102         .save           = NFQUEUE_save,
 103         .extra_opts     = NFQUEUE_opts,
 104 };
 105
 106 void _init(void)
 107 {
 108         xtables_register_target(&nfqueue_target);
 109         xtables_register_target(&nfqueue_target6);
 110 }