Git init

1 files changed, 263 insertions, 0 deletions

diff --git a/extensions/libip6t_icmp6.c b/extensions/libip6t_icmp6.c
new file mode 100644
index 0000000..fb321b3
--- /dev/null
+++ b/extensions/libip6t_icmp6.c
@@ -0,0 +1,263 @@
+/* Shared library add-on to ip6tables to add ICMP support. */
+#include <stdio.h>
+#include <netdb.h>
+#include <string.h>
+#include <stdlib.h>
+#include <getopt.h>
+#include <xtables.h>
+#include <limits.h> /* INT_MAX in ip6_tables.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(void)
+{
+	unsigned int i;
+	printf("Valid ICMPv6 Types:");
+
+	for (i = 0; i < ARRAY_SIZE(icmpv6_codes); ++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");
+}
+
+static void icmp6_help(void)
+{
+	printf(
+"icmpv6 match options:\n"
+"[!] --icmpv6-type typename	match icmpv6 type\n"
+"				(or numeric type or type/code)\n");
+	print_icmpv6types();
+}
+
+static const struct option icmp6_opts[] = {
+	{ "icmpv6-type", 1, NULL, '1' },
+	{ .name = NULL }
+};
+
+static void
+parse_icmpv6(const char *icmpv6type, u_int8_t *type, u_int8_t code[])
+{
+	static const unsigned int limit = ARRAY_SIZE(icmpv6_codes);
+	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)
+				xtables_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];
+		unsigned int number;
+
+		strcpy(buffer, icmpv6type);
+		slash = strchr(buffer, '/');
+
+		if (slash)
+			*slash = '\0';
+
+		if (!xtables_strtoui(buffer, NULL, &number, 0, UINT8_MAX))
+			xtables_error(PARAMETER_PROBLEM,
+				   "Invalid ICMPv6 type `%s'\n", buffer);
+		*type = number;
+		if (slash) {
+			if (!xtables_strtoui(slash+1, NULL, &number, 0, UINT8_MAX))
+				xtables_error(PARAMETER_PROBLEM,
+					   "Invalid ICMPv6 code `%s'\n",
+					   slash+1);
+			code[0] = code[1] = number;
+		} else {
+			code[0] = 0;
+			code[1] = 0xFF;
+		}
+	}
+}
+
+static void icmp6_init(struct xt_entry_match *m)
+{
+	struct ip6t_icmp *icmpv6info = (struct ip6t_icmp *)m->data;
+
+	icmpv6info->code[1] = 0xFF;
+}
+
+static int icmp6_parse(int c, char **argv, int invert, unsigned int *flags,
+                       const void *entry, struct xt_entry_match **match)
+{
+	struct ip6t_icmp *icmpv6info = (struct ip6t_icmp *)(*match)->data;
+
+	switch (c) {
+	case '1':
+		if (*flags == 1)
+			xtables_error(PARAMETER_PROBLEM,
+				   "icmpv6 match: only use --icmpv6-type once!");
+		xtables_check_inverse(optarg, &invert, &optind, 0, argv);
+		parse_icmpv6(optarg, &icmpv6info->type, 
+			     icmpv6info->code);
+		if (invert)
+			icmpv6info->invflags |= IP6T_ICMP_INV;
+		*flags = 1;
+		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 < ARRAY_SIZE(icmpv6_codes); ++i)
+			if (icmpv6_codes[i].type == type
+			    && icmpv6_codes[i].code_min == code_min
+			    && icmpv6_codes[i].code_max == code_max)
+				break;
+
+		if (i != ARRAY_SIZE(icmpv6_codes)) {
+			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);
+}
+
+static void icmp6_print(const void *ip, const struct xt_entry_match *match,
+                        int numeric)
+{
+	const struct ip6t_icmp *icmpv6 = (struct ip6t_icmp *)match->data;
+
+	printf("ipv6-icmp ");
+	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);
+}
+
+static void icmp6_save(const void *ip, const struct xt_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(" ");
+}
+
+static void icmp6_check(unsigned int flags)
+{
+	if (!flags)
+		xtables_error(PARAMETER_PROBLEM,
+			   "icmpv6 match: You must specify `--icmpv6-type'");
+}
+
+static struct xtables_match icmp6_mt6_reg = {
+	.name 		= "icmp6",
+	.version 	= XTABLES_VERSION,
+	.family		= NFPROTO_IPV6,
+	.size		= XT_ALIGN(sizeof(struct ip6t_icmp)),
+	.userspacesize	= XT_ALIGN(sizeof(struct ip6t_icmp)),
+	.help		= icmp6_help,
+	.init		= icmp6_init,
+	.parse		= icmp6_parse,
+	.final_check	= icmp6_check,
+	.print		= icmp6_print,
+	.save		= icmp6_save,
+	.extra_opts	= icmp6_opts,
+};
+
+void _init(void)
+{
+	xtables_register_match(&icmp6_mt6_reg);
+}