+++ /dev/null
-/* Shared library add-on to iptables to add TTL matching support
- * (C) 2000 by Harald Welte <laforge@gnumonks.org>
- *
- * $Id$
- *
- * This program is released under the terms of GNU GPL */
-
-#include <stdio.h>
-#include <stdlib.h>
-#include <string.h>
-#include <getopt.h>
-#include <iptables.h>
-
-#include <linux/netfilter_ipv4/ip_tables.h>
-#include <linux/netfilter_ipv4/ipt_ttl.h>
-
-static void ttl_help(void)
-{
- printf(
-"ttl match options:\n"
-" --ttl-eq value Match time to live value\n"
-" --ttl-lt value Match TTL < value\n"
-" --ttl-gt value Match TTL > value\n");
-}
-
-static int ttl_parse(int c, char **argv, int invert, unsigned int *flags,
- const void *entry, struct xt_entry_match **match)
-{
- struct ipt_ttl_info *info = (struct ipt_ttl_info *) (*match)->data;
- unsigned int value;
-
- check_inverse(optarg, &invert, &optind, 0);
-
- switch (c) {
- case '2':
- if (string_to_number(optarg, 0, 255, &value) == -1)
- exit_error(PARAMETER_PROBLEM,
- "ttl: Expected value between 0 and 255");
-
- if (invert)
- info->mode = IPT_TTL_NE;
- else
- info->mode = IPT_TTL_EQ;
-
- /* is 0 allowed? */
- info->ttl = value;
- break;
- case '3':
- if (string_to_number(optarg, 0, 255, &value) == -1)
- exit_error(PARAMETER_PROBLEM,
- "ttl: Expected value between 0 and 255");
-
- if (invert)
- exit_error(PARAMETER_PROBLEM,
- "ttl: unexpected `!'");
-
- info->mode = IPT_TTL_LT;
- info->ttl = value;
- break;
- case '4':
- if (string_to_number(optarg, 0, 255, &value) == -1)
- exit_error(PARAMETER_PROBLEM,
- "ttl: Expected value between 0 and 255");
-
- if (invert)
- exit_error(PARAMETER_PROBLEM,
- "ttl: unexpected `!'");
-
- info->mode = IPT_TTL_GT;
- info->ttl = value;
- break;
- default:
- return 0;
-
- }
-
- if (*flags)
- exit_error(PARAMETER_PROBLEM,
- "Can't specify TTL option twice");
- *flags = 1;
-
- return 1;
-}
-
-static void ttl_check(unsigned int flags)
-{
- if (!flags)
- exit_error(PARAMETER_PROBLEM,
- "TTL match: You must specify one of "
- "`--ttl-eq', `--ttl-lt', `--ttl-gt");
-}
-
-static void ttl_print(const void *ip, const struct xt_entry_match *match,
- int numeric)
-{
- const struct ipt_ttl_info *info =
- (struct ipt_ttl_info *) match->data;
-
- printf("TTL match ");
- switch (info->mode) {
- case IPT_TTL_EQ:
- printf("TTL == ");
- break;
- case IPT_TTL_NE:
- printf("TTL != ");
- break;
- case IPT_TTL_LT:
- printf("TTL < ");
- break;
- case IPT_TTL_GT:
- printf("TTL > ");
- break;
- }
- printf("%u ", info->ttl);
-}
-
-static void ttl_save(const void *ip, const struct xt_entry_match *match)
-{
- const struct ipt_ttl_info *info =
- (struct ipt_ttl_info *) match->data;
-
- switch (info->mode) {
- case IPT_TTL_EQ:
- printf("--ttl-eq ");
- break;
- case IPT_TTL_NE:
- printf("! --ttl-eq ");
- break;
- case IPT_TTL_LT:
- printf("--ttl-lt ");
- break;
- case IPT_TTL_GT:
- printf("--ttl-gt ");
- break;
- default:
- /* error */
- break;
- }
- printf("%u ", info->ttl);
-}
-
-static const struct option ttl_opts[] = {
- { "ttl", 1, NULL, '2' },
- { "ttl-eq", 1, NULL, '2'},
- { "ttl-lt", 1, NULL, '3'},
- { "ttl-gt", 1, NULL, '4'},
- { .name = NULL }
-};
-
-static struct xtables_match ttl_mt_reg = {
- .name = "ttl",
- .version = XTABLES_VERSION,
- .family = PF_INET,
- .size = XT_ALIGN(sizeof(struct ipt_ttl_info)),
- .userspacesize = XT_ALIGN(sizeof(struct ipt_ttl_info)),
- .help = ttl_help,
- .parse = ttl_parse,
- .final_check = ttl_check,
- .print = ttl_print,
- .save = ttl_save,
- .extra_opts = ttl_opts,
-};
-
-
-void _init(void)
-{
- xtables_register_match(&ttl_mt_reg);
-}