/* * "fuzzy" match extension for iptables * Hime Aguiar e Oliveira Jr. , 2002 - 2003 * * This program is free software; you can redistribute it and/or * modify it under the terms of the GNU General Public License; * either version 2 of the License, or any later version, as * published by the Free Software Foundation. */ #include #include #include #include #include #include #include #include "xt_fuzzy.h" #include "compat_user.h" static void fuzzy_mt_help(void) { printf( "fuzzy match options:\n" " --lower-limit number (in packets per second)\n" " --upper-limit number\n"); }; static const struct option fuzzy_mt_opts[] = { {.name = "lower-limit", .has_arg = true, .val = '1'}, {.name = "upper-limit", .has_arg = true, .val = '2'}, {NULL}, }; /* Initialize data structures */ static void fuzzy_mt_init(struct xt_entry_match *m) { struct xt_fuzzy_mtinfo *info = (void *)m->data; /* * Default rates (I will improve this very soon with something based * on real statistics of the running machine). */ info->minimum_rate = 1000; info->maximum_rate = 2000; } #define IPT_FUZZY_OPT_MINIMUM 0x01 #define IPT_FUZZY_OPT_MAXIMUM 0x02 static int fuzzy_mt_parse(int c, char **argv, int invert, unsigned int *flags, const void *entry, struct xt_entry_match **match) { struct xt_fuzzy_mtinfo *info = (void *)(*match)->data; uint32_t num; switch (c) { case '1': if (invert) xtables_error(PARAMETER_PROBLEM,"Can't specify ! --lower-limit"); if (*flags & IPT_FUZZY_OPT_MINIMUM) xtables_error(PARAMETER_PROBLEM,"Can't specify --lower-limit twice"); if (!xtables_strtoui(optarg, NULL, &num, 1, FUZZY_MAX_RATE) || num < 1) xtables_error(PARAMETER_PROBLEM,"BAD --lower-limit"); info->minimum_rate = num; *flags |= IPT_FUZZY_OPT_MINIMUM; return true; case '2': if (invert) xtables_error(PARAMETER_PROBLEM,"Can't specify ! --upper-limit"); if (*flags & IPT_FUZZY_OPT_MAXIMUM) xtables_error(PARAMETER_PROBLEM,"Can't specify --upper-limit twice"); if (!xtables_strtoui(optarg, NULL, &num, 1, FUZZY_MAX_RATE) || num < 1) xtables_error(PARAMETER_PROBLEM,"BAD --upper-limit"); info->maximum_rate = num; *flags |= IPT_FUZZY_OPT_MAXIMUM; return true; } return false; } static void fuzzy_mt_check(unsigned int flags) { } static void fuzzy_mt_save(const void *ip, const struct xt_entry_match *match) { const struct xt_fuzzy_mtinfo *info = (const void *)match->data; printf(" --lower-limit %u ", info->minimum_rate); printf(" --upper-limit %u ", info->maximum_rate); } static void fuzzy_mt_print(const void *ip, const struct xt_entry_match *match, int numeric) { printf(" -m fuzzy"); fuzzy_mt_save(ip, match); } static struct xtables_match fuzzy_mt_reg = { .name = "fuzzy", .revision = 1, .version = XTABLES_VERSION, .family = NFPROTO_UNSPEC, .size = XT_ALIGN(sizeof(struct xt_fuzzy_mtinfo)), .userspacesize = offsetof(struct xt_fuzzy_mtinfo, packets_total), .help = fuzzy_mt_help, .init = fuzzy_mt_init, .parse = fuzzy_mt_parse, .final_check = fuzzy_mt_check, .print = fuzzy_mt_print, .save = fuzzy_mt_save, .extra_opts = fuzzy_mt_opts, }; static __attribute__((constructor)) void fuzzy_mt_ldr(void) { xtables_register_match(&fuzzy_mt_reg); }