Merge commit 'origin/trunk@12184' into fedora

[iptables.git] / trunk / extensions / libxt_state.c

diff --git a/trunk/extensions/libxt_state.c b/trunk/extensions/libxt_state.c
new file mode 100644 (file)
index 0000000..c37fd70
--- /dev/null
+++ b/trunk/extensions/libxt_state.c
@@ -0,0 +1,176 @@
+/* Shared library add-on to iptables to add state tracking support. */
+#include <stdio.h>
+#include <netdb.h>
+#include <string.h>
+#include <stdlib.h>
+#include <getopt.h>
+#include <xtables.h>
+#include <linux/netfilter/nf_conntrack_common.h>
+#include <linux/netfilter/xt_state.h>
+
+#ifndef XT_STATE_UNTRACKED
+#define XT_STATE_UNTRACKED (1 << (IP_CT_NUMBER + 1))
+#endif
+
+/* Function which prints out usage message. */
+static void
+state_help(void)
+{
+       printf(
+"state match options:\n"
+" [!] --state [INVALID|ESTABLISHED|NEW|RELATED|UNTRACKED][,...]\n"
+"                              State(s) to match\n");
+}
+
+static const struct option state_opts[] = {
+       { "state", 1, NULL, '1' },
+       { .name = NULL }
+};
+
+static int
+state_parse_state(const char *state, size_t len, struct xt_state_info *sinfo)
+{
+       if (strncasecmp(state, "INVALID", len) == 0)
+               sinfo->statemask |= XT_STATE_INVALID;
+       else if (strncasecmp(state, "NEW", len) == 0)
+               sinfo->statemask |= XT_STATE_BIT(IP_CT_NEW);
+       else if (strncasecmp(state, "ESTABLISHED", len) == 0)
+               sinfo->statemask |= XT_STATE_BIT(IP_CT_ESTABLISHED);
+       else if (strncasecmp(state, "RELATED", len) == 0)
+               sinfo->statemask |= XT_STATE_BIT(IP_CT_RELATED);
+       else if (strncasecmp(state, "UNTRACKED", len) == 0)
+               sinfo->statemask |= XT_STATE_UNTRACKED;
+       else
+               return 0;
+       return 1;
+}
+
+static void
+state_parse_states(const char *arg, struct xt_state_info *sinfo)
+{
+       const char *comma;
+
+       while ((comma = strchr(arg, ',')) != NULL) {
+               if (comma == arg || !state_parse_state(arg, comma-arg, sinfo))
+                       exit_error(PARAMETER_PROBLEM, "Bad state `%s'", arg);
+               arg = comma+1;
+       }
+
+       if (strlen(arg) == 0 || !state_parse_state(arg, strlen(arg), sinfo))
+               exit_error(PARAMETER_PROBLEM, "Bad state `%s'", arg);
+}
+
+/* Function which parses command options; returns true if it
+   ate an option */
+static int
+state_parse(int c, char **argv, int invert, unsigned int *flags,
+      const void *entry,
+      struct xt_entry_match **match)
+{
+       struct xt_state_info *sinfo = (struct xt_state_info *)(*match)->data;
+
+       switch (c) {
+       case '1':
+               check_inverse(optarg, &invert, &optind, 0);
+
+               state_parse_states(argv[optind-1], sinfo);
+               if (invert)
+                       sinfo->statemask = ~sinfo->statemask;
+               *flags = 1;
+               break;
+
+       default:
+               return 0;
+       }
+
+       return 1;
+}
+
+/* Final check; must have specified --state. */
+static void state_final_check(unsigned int flags)
+{
+       if (!flags)
+               exit_error(PARAMETER_PROBLEM, "You must specify `--state'");
+}
+
+static void state_print_state(unsigned int statemask)
+{
+       const char *sep = "";
+
+       if (statemask & XT_STATE_INVALID) {
+               printf("%sINVALID", sep);
+               sep = ",";
+       }
+       if (statemask & XT_STATE_BIT(IP_CT_NEW)) {
+               printf("%sNEW", sep);
+               sep = ",";
+       }
+       if (statemask & XT_STATE_BIT(IP_CT_RELATED)) {
+               printf("%sRELATED", sep);
+               sep = ",";
+       }
+       if (statemask & XT_STATE_BIT(IP_CT_ESTABLISHED)) {
+               printf("%sESTABLISHED", sep);
+               sep = ",";
+       }
+       if (statemask & XT_STATE_UNTRACKED) {
+               printf("%sUNTRACKED", sep);
+               sep = ",";
+       }
+       printf(" ");
+}
+
+/* Prints out the matchinfo. */
+static void
+state_print(const void *ip,
+      const struct xt_entry_match *match,
+      int numeric)
+{
+       struct xt_state_info *sinfo = (struct xt_state_info *)match->data;
+
+       printf("state ");
+       state_print_state(sinfo->statemask);
+}
+
+/* Saves the matchinfo in parsable form to stdout. */
+static void state_save(const void *ip, const struct xt_entry_match *match)
+{
+       struct xt_state_info *sinfo = (struct xt_state_info *)match->data;
+
+       printf("--state ");
+       state_print_state(sinfo->statemask);
+}
+
+static struct xtables_match state_match = { 
+       .family         = AF_INET,
+       .name           = "state",
+       .version        = XTABLES_VERSION,
+       .size           = XT_ALIGN(sizeof(struct xt_state_info)),
+       .userspacesize  = XT_ALIGN(sizeof(struct xt_state_info)),
+       .help           = state_help,
+       .parse          = state_parse,
+       .final_check    = state_final_check,
+       .print          = state_print,
+       .save           = state_save,
+       .extra_opts     = state_opts,
+};
+
+static struct xtables_match state_match6 = { 
+       .family         = AF_INET6,
+       .name           = "state",
+       .version        = XTABLES_VERSION,
+       .size           = XT_ALIGN(sizeof(struct xt_state_info)),
+       .userspacesize  = XT_ALIGN(sizeof(struct xt_state_info)),
+       .help           = state_help,
+       .parse          = state_parse,
+       .final_check    = state_final_check,
+       .print          = state_print,
+       .save           = state_save,
+       .extra_opts     = state_opts,
+};
+
+void _init(void)
+{
+       xtables_register_match(&state_match);
+       xtables_register_match(&state_match6);
+}