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-rw-r--r--extensions/libipt_recent.c178
1 files changed, 178 insertions, 0 deletions
diff --git a/extensions/libipt_recent.c b/extensions/libipt_recent.c
new file mode 100644
index 00000000..8c4a1a33
--- /dev/null
+++ b/extensions/libipt_recent.c
@@ -0,0 +1,178 @@
+/* Shared library add-on to iptables to add recent matching support. */
+#include <stdio.h>
+#include <netdb.h>
+#include <string.h>
+#include <stdlib.h>
+#include <getopt.h>
+
+#include <iptables.h>
+#include <linux/netfilter_ipv4/ipt_recent.h>
+
+/* Function which prints out usage message. */
+static void
+help(void)
+{
+ printf(
+"recent v%s options:\n"
+"[!] --set Add source address to list, always matches.\n"
+"[!] --rcheck Match if source address in list.\n"
+"[!] --update Match if source address in list, also update last-seen time.\n"
+"[!] --remove Match if source address in list, also removes that address from list.\n"
+" --seconds seconds For check and update commands above.\n"
+" Specifies that the match will only occur if source address last seen within\n"
+" the last 'seconds' seconds.\n"
+" --hitcount hits For check and update commands above.\n"
+" Specifies that the match will only occur if source address seen hits times.\n"
+" May be used in conjunction with the seconds option.\n",
+NETFILTER_VERSION);
+
+}
+
+static struct option opts[] = {
+ { "set", 0, 0, 201 },
+ { "rcheck", 0, 0, 202 },
+ { "update", 0, 0, 203 },
+ { "seconds", 1, 0, 204 },
+ { "hitcount", 1, 0, 205 },
+ { "remove",0, 0, 206 },
+ {0}
+};
+
+/* Initialize the match. */
+static void
+init(struct ipt_entry_match *m, unsigned int *nfcache)
+{
+ *nfcache |= NFC_UNKNOWN;
+}
+
+/* Function which parses command options; returns true if it
+ ate an option */
+static int
+parse(int c, char **argv, int invert, unsigned int *flags,
+ const struct ipt_entry *entry,
+ unsigned int *nfcache,
+ struct ipt_entry_match **match)
+{
+ struct ipt_recent_info *info = (struct ipt_recent_info *)(*match)->data;
+
+ switch (c) {
+ case 201:
+ if (*flags) exit_error(PARAMETER_PROBLEM,
+ "recent: only one of `--set', `--check' "
+ "`--update' or `--remove' may be set");
+ if (check_inverse(optarg, &invert)) optind++;
+ info->check_set |= IPT_RECENT_SET;
+ if (invert) info->invert = 1;
+ *flags = 1;
+ break;
+
+ case 202:
+ if (*flags) exit_error(PARAMETER_PROBLEM,
+ "recent: only one of `--set', `--check' "
+ "`--update' or `--remove' may be set");
+ if (check_inverse(optarg, &invert)) optind++;
+ info->check_set |= IPT_RECENT_CHECK;
+ if(invert) info->invert = 1;
+ *flags = 1;
+ break;
+
+ case 203:
+ if (*flags) exit_error(PARAMETER_PROBLEM,
+ "recent: only one of `--set', `--check' "
+ "`--update' or `--remove' may be set");
+ if (check_inverse(optarg, &invert)) optind++;
+ info->check_set |= IPT_RECENT_UPDATE;
+ if (invert) info->invert = 1;
+ *flags = 1;
+ break;
+
+ case 206:
+ if (*flags) exit_error(PARAMETER_PROBLEM,
+ "recent: only one of `--set', `--check' "
+ "`--update' or `--remove' may be set");
+ if (check_inverse(optarg, &invert)) optind++;
+ info->check_set |= IPT_RECENT_REMOVE;
+ if (invert) info->invert = 1;
+ *flags = 1;
+ break;
+
+ case 204:
+ info->seconds = atoi(optarg);
+ break;
+
+ case 205:
+ info->hit_count = atoi(optarg);
+ break;
+
+ default:
+ return 0;
+ }
+ return 1;
+}
+
+/* Final check; must have specified a specific option. */
+static void
+final_check(unsigned int flags)
+{
+ if (!flags)
+ exit_error(PARAMETER_PROBLEM,
+ "recent: you must specify one of `--set', `--check' "
+ "`--update' or `--remove'");
+}
+
+/* Prints out the matchinfo. */
+static void
+print(const struct ipt_ip *ip,
+ const struct ipt_entry_match *match,
+ int numeric)
+{
+ struct ipt_recent_info *info = (struct ipt_recent_info *)match->data;
+
+ if (info->invert) fputc('!', stdout);
+
+ printf("recent: ");
+ if(info->check_set & IPT_RECENT_SET) printf("SET ");
+ if(info->check_set & IPT_RECENT_CHECK) printf("CHECK ");
+ if(info->check_set & IPT_RECENT_UPDATE) printf("UPDATE ");
+ if(info->check_set & IPT_RECENT_REMOVE) printf("REMOVE ");
+ if(info->seconds) printf("seconds: %d",info->seconds);
+ if(info->hit_count) printf("hit_count: %d",info->hit_count);
+}
+
+/* Saves the union ipt_matchinfo in parsable form to stdout. */
+static void
+save(const struct ipt_ip *ip, const struct ipt_entry_match *match)
+{
+ struct ipt_recent_info *info = (struct ipt_recent_info *)match;
+
+ if (info->invert) fputc('!', stdout);
+
+ printf("recent: ");
+ if(info->check_set & IPT_RECENT_SET) printf("SET ");
+ if(info->check_set & IPT_RECENT_CHECK) printf("CHECK ");
+ if(info->check_set & IPT_RECENT_UPDATE) printf("UPDATE ");
+ if(info->check_set & IPT_RECENT_REMOVE) printf("REMOVE ");
+ if(info->seconds) printf("seconds: ");
+ if(info->hit_count) printf("hit_count: ");
+}
+
+static
+struct iptables_match recent
+= { NULL,
+ "recent",
+ NETFILTER_VERSION,
+ IPT_ALIGN(sizeof(struct ipt_recent_info)),
+ IPT_ALIGN(sizeof(struct ipt_recent_info)),
+ &help,
+ &init,
+ &parse,
+ &final_check,
+ &print,
+ &save,
+ opts
+};
+
+void _init(void)
+{
+ register_match(&recent);
+}