Tizen 2.1 basesubmit/tizen_2.2/20130714.145952submit/tizen_2.1/20130424.225212accepted/tizen_2.1/20130425.0251492.2_release2.1b_releasetizen_2.1

1 files changed, 182 insertions, 0 deletions

diff --git a/extensions/libipt_NETMAP.c b/extensions/libipt_NETMAP.c
new file mode 100644
index 0000000..b05022b
--- /dev/null
+++ b/extensions/libipt_NETMAP.c
@@ -0,0 +1,182 @@
+/* Shared library add-on to iptables to add static NAT support.
+   Author: Svenning Soerensen <svenning@post5.tele.dk>
+*/
+
+#include <stdio.h>
+#include <netdb.h>
+#include <string.h>
+#include <stdlib.h>
+#include <getopt.h>
+#include <xtables.h>
+#include <net/netfilter/nf_nat.h>
+
+#define MODULENAME "NETMAP"
+
+static const struct option NETMAP_opts[] = {
+	{ "to", 1, NULL, '1' },
+	{ .name = NULL }
+};
+
+static void NETMAP_help(void)
+{
+	printf(MODULENAME" target options:\n"
+	       "  --%s address[/mask]\n"
+	       "				Network address to map to.\n\n",
+	       NETMAP_opts[0].name);
+}
+
+static u_int32_t
+bits2netmask(int bits)
+{
+	u_int32_t netmask, bm;
+
+	if (bits >= 32 || bits < 0)
+		return(~0);
+	for (netmask = 0, bm = 0x80000000; bits; bits--, bm >>= 1)
+		netmask |= bm;
+	return htonl(netmask);
+}
+
+static int
+netmask2bits(u_int32_t netmask)
+{
+	u_int32_t bm;
+	int bits;
+
+	netmask = ntohl(netmask);
+	for (bits = 0, bm = 0x80000000; netmask & bm; netmask <<= 1)
+		bits++;
+	if (netmask)
+		return -1; /* holes in netmask */
+	return bits;
+}
+
+static void NETMAP_init(struct xt_entry_target *t)
+{
+	struct nf_nat_multi_range *mr = (struct nf_nat_multi_range *)t->data;
+
+	/* Actually, it's 0, but it's ignored at the moment. */
+	mr->rangesize = 1;
+
+}
+
+/* Parses network address */
+static void
+parse_to(char *arg, struct nf_nat_range *range)
+{
+	char *slash;
+	const struct in_addr *ip;
+	u_int32_t netmask;
+	unsigned int bits;
+
+	range->flags |= IP_NAT_RANGE_MAP_IPS;
+	slash = strchr(arg, '/');
+	if (slash)
+		*slash = '\0';
+
+	ip = xtables_numeric_to_ipaddr(arg);
+	if (!ip)
+		xtables_error(PARAMETER_PROBLEM, "Bad IP address \"%s\"\n",
+			   arg);
+	range->min_ip = ip->s_addr;
+	if (slash) {
+		if (strchr(slash+1, '.')) {
+			ip = xtables_numeric_to_ipmask(slash+1);
+			if (!ip)
+				xtables_error(PARAMETER_PROBLEM, "Bad netmask \"%s\"\n",
+					   slash+1);
+			netmask = ip->s_addr;
+		}
+		else {
+			if (!xtables_strtoui(slash+1, NULL, &bits, 0, 32))
+				xtables_error(PARAMETER_PROBLEM, "Bad netmask \"%s\"\n",
+					   slash+1);
+			netmask = bits2netmask(bits);
+		}
+		/* Don't allow /0 (/1 is probably insane, too) */
+		if (netmask == 0)
+			xtables_error(PARAMETER_PROBLEM, "Netmask needed\n");
+	}
+	else
+		netmask = ~0;
+
+	if (range->min_ip & ~netmask) {
+		if (slash)
+			*slash = '/';
+		xtables_error(PARAMETER_PROBLEM, "Bad network address \"%s\"\n",
+			   arg);
+	}
+	range->max_ip = range->min_ip | ~netmask;
+}
+
+static int NETMAP_parse(int c, char **argv, int invert, unsigned int *flags,
+                        const void *entry, struct xt_entry_target **target)
+{
+	struct nf_nat_multi_range *mr
+		= (struct nf_nat_multi_range *)(*target)->data;
+
+	switch (c) {
+	case '1':
+		if (xtables_check_inverse(optarg, &invert, NULL, 0, argv))
+			xtables_error(PARAMETER_PROBLEM,
+				   "Unexpected `!' after --%s", NETMAP_opts[0].name);
+
+		parse_to(optarg, &mr->range[0]);
+		*flags = 1;
+		return 1;
+
+	default:
+		return 0;
+	}
+}
+
+static void NETMAP_check(unsigned int flags)
+{
+	if (!flags)
+		xtables_error(PARAMETER_PROBLEM,
+			   MODULENAME" needs --%s", NETMAP_opts[0].name);
+}
+
+static void NETMAP_print(const void *ip, const struct xt_entry_target *target,
+                         int numeric)
+{
+	const struct nf_nat_multi_range *mr = (const void *)target->data;
+	const struct nf_nat_range *r = &mr->range[0];
+	struct in_addr a;
+	int bits;
+
+	a.s_addr = r->min_ip;
+	printf("%s", xtables_ipaddr_to_numeric(&a));
+	a.s_addr = ~(r->min_ip ^ r->max_ip);
+	bits = netmask2bits(a.s_addr);
+	if (bits < 0)
+		printf("/%s", xtables_ipaddr_to_numeric(&a));
+	else
+		printf("/%d", bits);
+}
+
+static void NETMAP_save(const void *ip, const struct xt_entry_target *target)
+{
+	printf("--%s ", NETMAP_opts[0].name);
+	NETMAP_print(ip, target, 0);
+}
+
+static struct xtables_target netmap_tg_reg = {
+	.name		= MODULENAME,
+	.version	= XTABLES_VERSION,
+	.family		= NFPROTO_IPV4,
+	.size		= XT_ALIGN(sizeof(struct nf_nat_multi_range)),
+	.userspacesize	= XT_ALIGN(sizeof(struct nf_nat_multi_range)),
+	.help		= NETMAP_help,
+	.init		= NETMAP_init,
+	.parse		= NETMAP_parse,
+	.final_check	= NETMAP_check,
+	.print		= NETMAP_print,
+	.save		= NETMAP_save,
+	.extra_opts	= NETMAP_opts,
+};
+
+void _init(void)
+{
+	xtables_register_target(&netmap_tg_reg);
+}