--- /dev/null
+#include <stdio.h>
+#include <netdb.h>
+#include <string.h>
+#include <stdlib.h>
+#include <stddef.h>
+#include <getopt.h>
+
+#include <xtables.h>
+#include <linux/netfilter/xt_statistic.h>
+
+static void statistic_help(void)
+{
+ printf(
+"statistic match options:\n"
+" --mode mode Match mode (random, nth)\n"
+" random mode:\n"
+" --probability p Probability\n"
+" nth mode:\n"
+" --every n Match every nth packet\n"
+" --packet p Initial counter value (0 <= p <= n-1, default 0)\n");
+}
+
+static const struct option statistic_opts[] = {
+ { "mode", 1, NULL, '1' },
+ { "probability", 1, NULL, '2' },
+ { "every", 1, NULL, '3' },
+ { "packet", 1, NULL, '4' },
+ { .name = NULL }
+};
+
+static struct xt_statistic_info *global_info;
+
+static void statistic_mt_init(struct xt_entry_match *match)
+{
+ global_info = (void *)match->data;
+}
+
+static int
+statistic_parse(int c, char **argv, int invert, unsigned int *flags,
+ const void *entry, struct xt_entry_match **match)
+{
+ struct xt_statistic_info *info = (void *)(*match)->data;
+ double prob;
+
+ if (invert)
+ info->flags |= XT_STATISTIC_INVERT;
+
+ switch (c) {
+ case '1':
+ if (*flags & 0x1)
+ exit_error(PARAMETER_PROBLEM, "double --mode");
+ if (!strcmp(optarg, "random"))
+ info->mode = XT_STATISTIC_MODE_RANDOM;
+ else if (!strcmp(optarg, "nth"))
+ info->mode = XT_STATISTIC_MODE_NTH;
+ else
+ exit_error(PARAMETER_PROBLEM, "Bad mode `%s'", optarg);
+ *flags |= 0x1;
+ break;
+ case '2':
+ if (*flags & 0x2)
+ exit_error(PARAMETER_PROBLEM, "double --probability");
+ prob = atof(optarg);
+ if (prob < 0 || prob > 1)
+ exit_error(PARAMETER_PROBLEM,
+ "--probability must be between 0 and 1");
+ info->u.random.probability = 0x80000000 * prob;
+ *flags |= 0x2;
+ break;
+ case '3':
+ if (*flags & 0x4)
+ exit_error(PARAMETER_PROBLEM, "double --every");
+ if (string_to_number(optarg, 0, 0xFFFFFFFF,
+ &info->u.nth.every) == -1)
+ exit_error(PARAMETER_PROBLEM,
+ "cannot parse --every `%s'", optarg);
+ if (info->u.nth.every == 0)
+ exit_error(PARAMETER_PROBLEM, "--every cannot be 0");
+ info->u.nth.every--;
+ *flags |= 0x4;
+ break;
+ case '4':
+ if (*flags & 0x8)
+ exit_error(PARAMETER_PROBLEM, "double --packet");
+ if (string_to_number(optarg, 0, 0xFFFFFFFF,
+ &info->u.nth.packet) == -1)
+ exit_error(PARAMETER_PROBLEM,
+ "cannot parse --packet `%s'", optarg);
+ *flags |= 0x8;
+ break;
+ default:
+ return 0;
+ }
+ return 1;
+}
+
+/* Final check; must have specified --mark. */
+static void statistic_check(unsigned int flags)
+{
+ if (!(flags & 0x1))
+ exit_error(PARAMETER_PROBLEM, "no mode specified");
+ if ((flags & 0x2) && (flags & (0x4 | 0x8)))
+ exit_error(PARAMETER_PROBLEM,
+ "both nth and random parameters given");
+ if (flags & 0x2 && global_info->mode != XT_STATISTIC_MODE_RANDOM)
+ exit_error(PARAMETER_PROBLEM,
+ "--probability can only be used in random mode");
+ if (flags & 0x4 && global_info->mode != XT_STATISTIC_MODE_NTH)
+ exit_error(PARAMETER_PROBLEM,
+ "--every can only be used in nth mode");
+ if (flags & 0x8 && global_info->mode != XT_STATISTIC_MODE_NTH)
+ exit_error(PARAMETER_PROBLEM,
+ "--packet can only be used in nth mode");
+ if ((flags & 0x8) && !(flags & 0x4))
+ exit_error(PARAMETER_PROBLEM,
+ "--packet can only be used with --every");
+ /* at this point, info->u.nth.every have been decreased. */
+ if (global_info->u.nth.packet > global_info->u.nth.every)
+ exit_error(PARAMETER_PROBLEM,
+ "the --packet p must be 0 <= p <= n-1");
+
+
+ global_info->u.nth.count = global_info->u.nth.every -
+ global_info->u.nth.packet;
+}
+
+/* Prints out the matchinfo. */
+static void print_match(const struct xt_statistic_info *info, char *prefix)
+{
+ if (info->flags & XT_STATISTIC_INVERT)
+ printf("! ");
+
+ switch (info->mode) {
+ case XT_STATISTIC_MODE_RANDOM:
+ printf("%smode random %sprobability %f ", prefix, prefix,
+ 1.0 * info->u.random.probability / 0x80000000);
+ break;
+ case XT_STATISTIC_MODE_NTH:
+ printf("%smode nth %severy %u ", prefix, prefix,
+ info->u.nth.every + 1);
+ if (info->u.nth.packet)
+ printf("%spacket %u ", prefix, info->u.nth.packet);
+ break;
+ }
+}
+
+static void
+statistic_print(const void *ip, const struct xt_entry_match *match, int numeric)
+{
+ struct xt_statistic_info *info = (struct xt_statistic_info *)match->data;
+
+ printf("statistic ");
+ print_match(info, "");
+}
+
+/* Saves the union ipt_matchinfo in parsable form to stdout. */
+static void statistic_save(const void *ip, const struct xt_entry_match *match)
+{
+ struct xt_statistic_info *info = (struct xt_statistic_info *)match->data;
+
+ print_match(info, "--");
+}
+
+static struct xtables_match statistic_match = {
+ .family = AF_UNSPEC,
+ .name = "statistic",
+ .version = XTABLES_VERSION,
+ .size = XT_ALIGN(sizeof(struct xt_statistic_info)),
+ .userspacesize = offsetof(struct xt_statistic_info, u.nth.count),
+ .init = statistic_mt_init,
+ .help = statistic_help,
+ .parse = statistic_parse,
+ .final_check = statistic_check,
+ .print = statistic_print,
+ .save = statistic_save,
+ .extra_opts = statistic_opts,
+};
+
+void _init(void)
+{
+ xtables_register_match(&statistic_match);
+}
git://git.onelab.eu / iptables.git / blobdiff