Major icmpv6 cleanup / fixes by Kis-Szabo Andras.
diff --git a/extensions/libip6t_icmpv6.c b/extensions/libip6t_icmpv6.c
new file mode 100644
index 0000000..41ae5ca
--- /dev/null
+++ b/extensions/libip6t_icmpv6.c
@@ -0,0 +1,281 @@
+/* Shared library add-on to iptables to add ICMP support. */
+#include <stdio.h>
+#include <netdb.h>
+#include <string.h>
+#include <stdlib.h>
+#include <getopt.h>
+#include <ip6tables.h>
+#include <linux/netfilter_ipv6/ip6_tables.h>
+
+struct icmpv6_names {
+ const char *name;
+ u_int8_t type;
+ u_int8_t code_min, code_max;
+};
+
+static const struct icmpv6_names icmpv6_codes[] = {
+ { "destination-unreachable", 1, 0, 0xFF },
+ { "no-route", 1, 0, 0 },
+ { "communication-prohibited", 1, 1, 1 },
+ { "address-unreachable", 1, 3, 3 },
+ { "port-unreachable", 1, 4, 4 },
+
+ { "packet-too-big", 2, 0, 0xFF },
+
+ { "time-exceeded", 3, 0, 0xFF },
+ /* Alias */ { "ttl-exceeded", 3, 0, 0xFF },
+ { "ttl-zero-during-transit", 3, 0, 0 },
+ { "ttl-zero-during-reassembly", 3, 1, 1 },
+
+ { "parameter-problem", 4, 0, 0xFF },
+ { "bad-header", 4, 0, 0 },
+ { "unknown-header-type", 4, 1, 1 },
+ { "unknown-option", 4, 2, 2 },
+
+ { "echo-request", 128, 0, 0xFF },
+ /* Alias */ { "ping", 128, 0, 0xFF },
+
+ { "echo-reply", 129, 0, 0xFF },
+ /* Alias */ { "pong", 129, 0, 0xFF },
+
+ { "router-solicitation", 133, 0, 0xFF },
+
+ { "router-advertisement", 134, 0, 0xFF },
+
+ { "neighbour-solicitation", 135, 0, 0xFF },
+ /* Alias */ { "neighbor-solicitation", 135, 0, 0xFF },
+
+ { "neighbour-advertisement", 136, 0, 0xFF },
+ /* Alias */ { "neighbor-advertisement", 136, 0, 0xFF },
+
+ { "redirect", 137, 0, 0xFF },
+
+};
+
+static void
+print_icmpv6types()
+{
+ unsigned int i;
+ printf("Valid ICMPv6 Types:");
+
+ for (i = 0; i < sizeof(icmpv6_codes)/sizeof(struct icmpv6_names); i++) {
+ if (i && icmpv6_codes[i].type == icmpv6_codes[i-1].type) {
+ if (icmpv6_codes[i].code_min == icmpv6_codes[i-1].code_min
+ && (icmpv6_codes[i].code_max
+ == icmpv6_codes[i-1].code_max))
+ printf(" (%s)", icmpv6_codes[i].name);
+ else
+ printf("\n %s", icmpv6_codes[i].name);
+ }
+ else
+ printf("\n%s", icmpv6_codes[i].name);
+ }
+ printf("\n");
+}
+
+/* Function which prints out usage message. */
+static void
+help(void)
+{
+ printf(
+"ICMPv6 v%s options:\n"
+" --icmpv6-type [!] typename match icmpv6 type\n"
+" (or numeric type or type/code)\n"
+"\n", NETFILTER_VERSION);
+ print_icmpv6types();
+}
+
+static struct option opts[] = {
+ { "icmpv6-type", 1, 0, '1' },
+ {0}
+};
+
+static unsigned int
+parse_icmpv6(const char *icmpv6type, u_int8_t *type, u_int8_t code[])
+{
+ unsigned int limit = sizeof(icmpv6_codes)/sizeof(struct icmpv6_names);
+ unsigned int match = limit;
+ unsigned int i;
+
+ for (i = 0; i < limit; i++) {
+ if (strncasecmp(icmpv6_codes[i].name, icmpv6type, strlen(icmpv6type))
+ == 0) {
+ if (match != limit)
+ exit_error(PARAMETER_PROBLEM,
+ "Ambiguous ICMPv6 type `%s':"
+ " `%s' or `%s'?",
+ icmpv6type,
+ icmpv6_codes[match].name,
+ icmpv6_codes[i].name);
+ match = i;
+ }
+ }
+
+ if (match != limit) {
+ *type = icmpv6_codes[match].type;
+ code[0] = icmpv6_codes[match].code_min;
+ code[1] = icmpv6_codes[match].code_max;
+ } else {
+ char *slash;
+ char buffer[strlen(icmpv6type) + 1];
+ int number;
+
+ strcpy(buffer, icmpv6type);
+ slash = strchr(buffer, '/');
+
+ if (slash)
+ *slash = '\0';
+
+ number = string_to_number(buffer, 0, 255);
+ if (number == -1)
+ exit_error(PARAMETER_PROBLEM,
+ "Invalid ICMPv6 type `%s'\n", buffer);
+ *type = number;
+ if (slash) {
+ number = string_to_number(slash+1, 0, 255);
+ if (number == -1)
+ exit_error(PARAMETER_PROBLEM,
+ "Invalid ICMPv6 code `%s'\n",
+ slash+1);
+ code[0] = code[1] = number;
+ } else {
+ code[0] = 0;
+ code[1] = 0xFF;
+ }
+ }
+
+ if (code[0] == 0 && code[1] == 0xFF)
+ return NFC_IP6_SRC_PT;
+ else return NFC_IP6_SRC_PT | NFC_IP6_DST_PT;
+}
+
+/* Initialize the match. */
+static void
+init(struct ip6t_entry_match *m, unsigned int *nfcache)
+{
+ struct ip6t_icmp *icmpv6info = (struct ip6t_icmp *)m->data;
+
+ icmpv6info->code[1] = 0xFF;
+}
+
+/* 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 ip6t_entry *entry,
+ unsigned int *nfcache,
+ struct ip6t_entry_match **match)
+{
+ struct ip6t_icmp *icmpv6info = (struct ip6t_icmp *)(*match)->data;
+
+ switch (c) {
+ case '1':
+ if (check_inverse(optarg, &invert))
+ optind++;
+ *nfcache |= parse_icmpv6(argv[optind-1],
+ &icmpv6info->type,
+ icmpv6info->code);
+ if (invert)
+ icmpv6info->invflags |= IP6T_ICMP_INV;
+ break;
+
+ default:
+ return 0;
+ }
+
+ return 1;
+}
+
+static void print_icmpv6type(u_int8_t type,
+ u_int8_t code_min, u_int8_t code_max,
+ int invert,
+ int numeric)
+{
+ if (!numeric) {
+ unsigned int i;
+
+ for (i = 0;
+ i < sizeof(icmpv6_codes)/sizeof(struct icmpv6_names);
+ i++) {
+ if (icmpv6_codes[i].type == type
+ && icmpv6_codes[i].code_min == code_min
+ && icmpv6_codes[i].code_max == code_max)
+ break;
+ }
+
+ if (i != sizeof(icmpv6_codes)/sizeof(struct icmpv6_names)) {
+ printf("%s%s ",
+ invert ? "!" : "",
+ icmpv6_codes[i].name);
+ return;
+ }
+ }
+
+ if (invert)
+ printf("!");
+
+ printf("type %u", type);
+ if (code_min == 0 && code_max == 0xFF)
+ printf(" ");
+ else if (code_min == code_max)
+ printf(" code %u ", code_min);
+ else
+ printf(" codes %u-%u ", code_min, code_max);
+}
+
+/* Prints out the union ipt_matchinfo. */
+static void
+print(const struct ip6t_ip6 *ip,
+ const struct ip6t_entry_match *match,
+ int numeric)
+{
+ const struct ip6t_icmp *icmpv6 = (struct ip6t_icmp *)match->data;
+
+ printf("icmpv6 ");
+ print_icmpv6type(icmpv6->type, icmpv6->code[0], icmpv6->code[1],
+ icmpv6->invflags & IP6T_ICMP_INV,
+ numeric);
+
+ if (icmpv6->invflags & ~IP6T_ICMP_INV)
+ printf("Unknown invflags: 0x%X ",
+ icmpv6->invflags & ~IP6T_ICMP_INV);
+}
+
+/* Saves the match in parsable form to stdout. */
+static void save(const struct ip6t_ip6 *ip, const struct ip6t_entry_match *match)
+{
+ const struct ip6t_icmp *icmpv6 = (struct ip6t_icmp *)match->data;
+
+ if (icmpv6->invflags & IP6T_ICMP_INV)
+ printf("! ");
+
+ printf("--icmpv6-type %u", icmpv6->type);
+ if (icmpv6->code[0] != 0 || icmpv6->code[1] != 0xFF)
+ printf("/%u", icmpv6->code[0]);
+ printf(" ");
+}
+
+/* Final check; we don't care. */
+static void final_check(unsigned int flags)
+{
+}
+
+struct ip6tables_match icmpv6
+= { NULL,
+ "icmpv6",
+ NETFILTER_VERSION,
+ IP6T_ALIGN(sizeof(struct ip6t_icmp)),
+ IP6T_ALIGN(sizeof(struct ip6t_icmp)),
+ &help,
+ &init,
+ &parse,
+ &final_check,
+ &print,
+ &save,
+ opts
+};
+
+void _init(void)
+{
+ register_match6(&icmpv6);
+}