--- /dev/null
+/* Shared library add-on to ip6tables to add AH support. */
+#include <stdio.h>
+#include <netdb.h>
+#include <string.h>
+#include <stdlib.h>
+#include <getopt.h>
+#include <errno.h>
+#include <ip6tables.h>
+#include <linux/netfilter_ipv6/ip6t_ah.h>
+
+/* Function which prints out usage message. */
+static void ah_help(void)
+{
+ printf(
+"ah match options:\n"
+" --ahspi [!] spi[:spi] match spi (range)\n"
+" --ahlen [!] length total length of this header\n"
+" --ahres check the reserved filed, too\n");
+}
+
+static const struct option ah_opts[] = {
+ { .name = "ahspi", .has_arg = 1, .val = '1' },
+ { .name = "ahlen", .has_arg = 1, .val = '2' },
+ { .name = "ahres", .has_arg = 0, .val = '3' },
+ { .name = NULL }
+};
+
+static u_int32_t
+parse_ah_spi(const char *spistr, const char *typestr)
+{
+ unsigned long int spi;
+ char* ep;
+
+ spi = strtoul(spistr, &ep, 0);
+
+ if ( spistr == ep )
+ exit_error(PARAMETER_PROBLEM,
+ "AH no valid digits in %s `%s'", typestr, spistr);
+
+ if ( spi == ULONG_MAX && errno == ERANGE )
+ exit_error(PARAMETER_PROBLEM,
+ "%s `%s' specified too big: would overflow",
+ typestr, spistr);
+
+ if ( *spistr != '\0' && *ep != '\0' )
+ exit_error(PARAMETER_PROBLEM,
+ "AH error parsing %s `%s'", typestr, 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, "spi");
+ else {
+ *cp = '\0';
+ cp++;
+
+ spis[0] = buffer[0] ? parse_ah_spi(buffer, "spi") : 0;
+ spis[1] = cp[0] ? parse_ah_spi(cp, "spi") : 0xFFFFFFFF;
+ }
+ free(buffer);
+}
+
+/* Initialize the match. */
+static void ah_init(struct xt_entry_match *m)
+{
+ struct ip6t_ah *ahinfo = (struct ip6t_ah *)m->data;
+
+ ahinfo->spis[1] = 0xFFFFFFFF;
+ ahinfo->hdrlen = 0;
+ ahinfo->hdrres = 0;
+}
+
+/* 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 ip6t_ah *ahinfo = (struct ip6t_ah *)(*match)->data;
+
+ switch (c) {
+ case '1':
+ if (*flags & IP6T_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 |= IP6T_AH_INV_SPI;
+ *flags |= IP6T_AH_SPI;
+ break;
+ case '2':
+ if (*flags & IP6T_AH_LEN)
+ exit_error(PARAMETER_PROBLEM,
+ "Only one `--ahlen' allowed");
+ check_inverse(optarg, &invert, &optind, 0);
+ ahinfo->hdrlen = parse_ah_spi(argv[optind-1], "length");
+ if (invert)
+ ahinfo->invflags |= IP6T_AH_INV_LEN;
+ *flags |= IP6T_AH_LEN;
+ break;
+ case '3':
+ if (*flags & IP6T_AH_RES)
+ exit_error(PARAMETER_PROBLEM,
+ "Only one `--ahres' allowed");
+ ahinfo->hdrres = 1;
+ *flags |= IP6T_AH_RES;
+ 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) {
+ if (min == max)
+ printf("%s:%s%u ", name, inv, min);
+ else
+ printf("%ss:%s%u:%u ", name, inv, min, max);
+ }
+}
+
+static void
+print_len(const char *name, u_int32_t len, int invert)
+{
+ const char *inv = invert ? "!" : "";
+
+ if (len != 0 || invert)
+ printf("%s:%s%u ", name, inv, len);
+}
+
+/* Prints out the union ip6t_matchinfo. */
+static void ah_print(const void *ip, const struct xt_entry_match *match,
+ int numeric)
+{
+ const struct ip6t_ah *ah = (struct ip6t_ah *)match->data;
+
+ printf("ah ");
+ print_spis("spi", ah->spis[0], ah->spis[1],
+ ah->invflags & IP6T_AH_INV_SPI);
+ print_len("length", ah->hdrlen,
+ ah->invflags & IP6T_AH_INV_LEN);
+
+ if (ah->hdrres)
+ printf("reserved ");
+
+ if (ah->invflags & ~IP6T_AH_INV_MASK)
+ printf("Unknown invflags: 0x%X ",
+ ah->invflags & ~IP6T_AH_INV_MASK);
+}
+
+/* Saves the union ip6t_matchinfo in parsable form to stdout. */
+static void ah_save(const void *ip, const struct xt_entry_match *match)
+{
+ const struct ip6t_ah *ahinfo = (struct ip6t_ah *)match->data;
+
+ if (!(ahinfo->spis[0] == 0
+ && ahinfo->spis[1] == 0xFFFFFFFF)) {
+ printf("--ahspi %s",
+ (ahinfo->invflags & IP6T_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]);
+ }
+
+ if (ahinfo->hdrlen != 0 || (ahinfo->invflags & IP6T_AH_INV_LEN) ) {
+ printf("--ahlen %s%u ",
+ (ahinfo->invflags & IP6T_AH_INV_LEN) ? "! " : "",
+ ahinfo->hdrlen);
+ }
+
+ if (ahinfo->hdrres != 0 )
+ printf("--ahres ");
+}
+
+static struct xtables_match ah_mt6_reg = {
+ .name = "ah",
+ .version = XTABLES_VERSION,
+ .family = PF_INET6,
+ .size = XT_ALIGN(sizeof(struct ip6t_ah)),
+ .userspacesize = XT_ALIGN(sizeof(struct ip6t_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_mt6_reg);
+}
git://git.onelab.eu / iptables.git / blobdiff