Merge commit 'origin/trunk@12184' into fedora
[iptables.git] / trunk / extensions / libipt_ah.c
diff --git a/trunk/extensions/libipt_ah.c b/trunk/extensions/libipt_ah.c
new file mode 100644 (file)
index 0000000..182b51a
--- /dev/null
@@ -0,0 +1,176 @@
+/* Shared library add-on to iptables to add AH support. */
+#include <stdio.h>
+#include <netdb.h>
+#include <string.h>
+#include <stdlib.h>
+#include <getopt.h>
+#include <errno.h>
+#include <iptables.h>
+#include <linux/netfilter_ipv4/ipt_ah.h>
+                                        
+/* Function which prints out usage message. */
+static void ah_help(void)
+{
+       printf(
+"ah match options:\n"
+" --ahspi [!] spi[:spi]\n"
+"                              match spi (range)\n");
+}
+
+static const struct option ah_opts[] = {
+       { "ahspi", 1, NULL, '1' },
+       { .name = NULL }
+};
+
+static u_int32_t
+parse_ah_spi(const char *spistr)
+{
+       unsigned long int spi;
+       char* ep;
+
+       spi =  strtoul(spistr,&ep,0) ;
+
+       if ( spistr == ep ) {
+               exit_error(PARAMETER_PROBLEM,
+                          "AH no valid digits in spi `%s'", spistr);
+       }
+       if ( spi == ULONG_MAX  && errno == ERANGE ) {
+               exit_error(PARAMETER_PROBLEM,
+                          "spi `%s' specified too big: would overflow", spistr);
+       }       
+       if ( *spistr != '\0'  && *ep != '\0' ) {
+               exit_error(PARAMETER_PROBLEM,
+                          "AH error parsing spi `%s'", spistr);
+       }
+       return (u_int32_t) spi;
+}
+
+static void
+parse_ah_spis(const char *spistring, u_int32_t *spis)
+{
+       char *buffer;
+       char *cp;
+
+       buffer = strdup(spistring);
+       if ((cp = strchr(buffer, ':')) == NULL)
+               spis[0] = spis[1] = parse_ah_spi(buffer);
+       else {
+               *cp = '\0';
+               cp++;
+
+               spis[0] = buffer[0] ? parse_ah_spi(buffer) : 0;
+               spis[1] = cp[0] ? parse_ah_spi(cp) : 0xFFFFFFFF;
+       }
+       free(buffer);
+}
+
+/* Initialize the match. */
+static void ah_init(struct xt_entry_match *m)
+{
+       struct ipt_ah *ahinfo = (struct ipt_ah *)m->data;
+
+       ahinfo->spis[1] = 0xFFFFFFFF;
+}
+
+#define AH_SPI 0x01
+
+/* Function which parses command options; returns true if it
+   ate an option */
+static int ah_parse(int c, char **argv, int invert, unsigned int *flags,
+                    const void *entry, struct xt_entry_match **match)
+{
+       struct ipt_ah *ahinfo = (struct ipt_ah *)(*match)->data;
+
+       switch (c) {
+       case '1':
+               if (*flags & AH_SPI)
+                       exit_error(PARAMETER_PROBLEM,
+                                  "Only one `--ahspi' allowed");
+               check_inverse(optarg, &invert, &optind, 0);
+               parse_ah_spis(argv[optind-1], ahinfo->spis);
+               if (invert)
+                       ahinfo->invflags |= IPT_AH_INV_SPI;
+               *flags |= AH_SPI;
+               break;
+       default:
+               return 0;
+       }
+
+       return 1;
+}
+
+static void
+print_spis(const char *name, u_int32_t min, u_int32_t max,
+           int invert)
+{
+       const char *inv = invert ? "!" : "";
+
+       if (min != 0 || max != 0xFFFFFFFF || invert) {
+               printf("%s", name);
+               if (min == max) {
+                       printf(":%s", inv);
+                       printf("%u", min);
+               } else {
+                       printf("s:%s", inv);
+                       printf("%u",min);
+                       printf(":");
+                       printf("%u",max);
+               }
+               printf(" ");
+       }
+}
+
+/* Prints out the union ipt_matchinfo. */
+static void ah_print(const void *ip, const struct xt_entry_match *match,
+                     int numeric)
+{
+       const struct ipt_ah *ah = (struct ipt_ah *)match->data;
+
+       printf("ah ");
+       print_spis("spi", ah->spis[0], ah->spis[1],
+                   ah->invflags & IPT_AH_INV_SPI);
+       if (ah->invflags & ~IPT_AH_INV_MASK)
+               printf("Unknown invflags: 0x%X ",
+                      ah->invflags & ~IPT_AH_INV_MASK);
+}
+
+/* Saves the union ipt_matchinfo in parsable form to stdout. */
+static void ah_save(const void *ip, const struct xt_entry_match *match)
+{
+       const struct ipt_ah *ahinfo = (struct ipt_ah *)match->data;
+
+       if (!(ahinfo->spis[0] == 0
+           && ahinfo->spis[1] == 0xFFFFFFFF)) {
+               printf("--ahspi %s", 
+                       (ahinfo->invflags & IPT_AH_INV_SPI) ? "! " : "");
+               if (ahinfo->spis[0]
+                   != ahinfo->spis[1])
+                       printf("%u:%u ",
+                              ahinfo->spis[0],
+                              ahinfo->spis[1]);
+               else
+                       printf("%u ",
+                              ahinfo->spis[0]);
+       }
+
+}
+
+static struct xtables_match ah_mt_reg = {
+       .name           = "ah",
+       .version        = XTABLES_VERSION,
+       .family         = PF_INET,
+       .size           = XT_ALIGN(sizeof(struct ipt_ah)),
+       .userspacesize  = XT_ALIGN(sizeof(struct ipt_ah)),
+       .help           = ah_help,
+       .init           = ah_init,
+       .parse          = ah_parse,
+       .print          = ah_print,
+       .save           = ah_save,
+       .extra_opts     = ah_opts,
+};
+
+void
+_init(void)
+{
+       xtables_register_match(&ah_mt_reg);
+}