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Diffstat (limited to 'net/ipv4/netfilter/ipt_MASQUERADE.c')
-rw-r--r--net/ipv4/netfilter/ipt_MASQUERADE.c91
1 files changed, 91 insertions, 0 deletions
diff --git a/net/ipv4/netfilter/ipt_MASQUERADE.c b/net/ipv4/netfilter/ipt_MASQUERADE.c
new file mode 100644
index 000000000..da7f02a0b
--- /dev/null
+++ b/net/ipv4/netfilter/ipt_MASQUERADE.c
@@ -0,0 +1,91 @@
+/* Masquerade. Simple mapping which alters range to a local IP address
+ (depending on route). */
+
+/* (C) 1999-2001 Paul `Rusty' Russell
+ * (C) 2002-2006 Netfilter Core Team <coreteam@netfilter.org>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
+#include <linux/types.h>
+#include <linux/inetdevice.h>
+#include <linux/ip.h>
+#include <linux/timer.h>
+#include <linux/module.h>
+#include <linux/netfilter.h>
+#include <net/protocol.h>
+#include <net/ip.h>
+#include <net/checksum.h>
+#include <net/route.h>
+#include <linux/netfilter_ipv4.h>
+#include <linux/netfilter/x_tables.h>
+#include <net/netfilter/nf_nat.h>
+#include <net/netfilter/ipv4/nf_nat_masquerade.h>
+
+MODULE_LICENSE("GPL");
+MODULE_AUTHOR("Netfilter Core Team <coreteam@netfilter.org>");
+MODULE_DESCRIPTION("Xtables: automatic-address SNAT");
+
+/* FIXME: Multiple targets. --RR */
+static int masquerade_tg_check(const struct xt_tgchk_param *par)
+{
+ const struct nf_nat_ipv4_multi_range_compat *mr = par->targinfo;
+
+ if (mr->range[0].flags & NF_NAT_RANGE_MAP_IPS) {
+ pr_debug("bad MAP_IPS.\n");
+ return -EINVAL;
+ }
+ if (mr->rangesize != 1) {
+ pr_debug("bad rangesize %u\n", mr->rangesize);
+ return -EINVAL;
+ }
+ return 0;
+}
+
+static unsigned int
+masquerade_tg(struct sk_buff *skb, const struct xt_action_param *par)
+{
+ struct nf_nat_range range;
+ const struct nf_nat_ipv4_multi_range_compat *mr;
+
+ mr = par->targinfo;
+ range.flags = mr->range[0].flags;
+ range.min_proto = mr->range[0].min;
+ range.max_proto = mr->range[0].max;
+
+ return nf_nat_masquerade_ipv4(skb, par->hooknum, &range, par->out);
+}
+
+static struct xt_target masquerade_tg_reg __read_mostly = {
+ .name = "MASQUERADE",
+ .family = NFPROTO_IPV4,
+ .target = masquerade_tg,
+ .targetsize = sizeof(struct nf_nat_ipv4_multi_range_compat),
+ .table = "nat",
+ .hooks = 1 << NF_INET_POST_ROUTING,
+ .checkentry = masquerade_tg_check,
+ .me = THIS_MODULE,
+};
+
+static int __init masquerade_tg_init(void)
+{
+ int ret;
+
+ ret = xt_register_target(&masquerade_tg_reg);
+
+ if (ret == 0)
+ nf_nat_masquerade_ipv4_register_notifier();
+
+ return ret;
+}
+
+static void __exit masquerade_tg_exit(void)
+{
+ xt_unregister_target(&masquerade_tg_reg);
+ nf_nat_masquerade_ipv4_unregister_notifier();
+}
+
+module_init(masquerade_tg_init);
+module_exit(masquerade_tg_exit);