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-rw-r--r--net/netfilter/xt_nat.c247
1 files changed, 247 insertions, 0 deletions
diff --git a/net/netfilter/xt_nat.c b/net/netfilter/xt_nat.c
new file mode 100644
index 000000000..b4f7bbc3f
--- /dev/null
+++ b/net/netfilter/xt_nat.c
@@ -0,0 +1,247 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * (C) 1999-2001 Paul `Rusty' Russell
+ * (C) 2002-2006 Netfilter Core Team <coreteam@netfilter.org>
+ * (C) 2011 Patrick McHardy <kaber@trash.net>
+ */
+
+#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
+
+#include <linux/module.h>
+#include <linux/skbuff.h>
+#include <linux/netfilter.h>
+#include <linux/netfilter/x_tables.h>
+#include <net/netfilter/nf_nat.h>
+
+static int xt_nat_checkentry_v0(const struct xt_tgchk_param *par)
+{
+ const struct nf_nat_ipv4_multi_range_compat *mr = par->targinfo;
+
+ if (mr->rangesize != 1) {
+ pr_info_ratelimited("multiple ranges no longer supported\n");
+ return -EINVAL;
+ }
+ return nf_ct_netns_get(par->net, par->family);
+}
+
+static int xt_nat_checkentry(const struct xt_tgchk_param *par)
+{
+ return nf_ct_netns_get(par->net, par->family);
+}
+
+static void xt_nat_destroy(const struct xt_tgdtor_param *par)
+{
+ nf_ct_netns_put(par->net, par->family);
+}
+
+static void xt_nat_convert_range(struct nf_nat_range2 *dst,
+ const struct nf_nat_ipv4_range *src)
+{
+ memset(&dst->min_addr, 0, sizeof(dst->min_addr));
+ memset(&dst->max_addr, 0, sizeof(dst->max_addr));
+ memset(&dst->base_proto, 0, sizeof(dst->base_proto));
+
+ dst->flags = src->flags;
+ dst->min_addr.ip = src->min_ip;
+ dst->max_addr.ip = src->max_ip;
+ dst->min_proto = src->min;
+ dst->max_proto = src->max;
+}
+
+static unsigned int
+xt_snat_target_v0(struct sk_buff *skb, const struct xt_action_param *par)
+{
+ const struct nf_nat_ipv4_multi_range_compat *mr = par->targinfo;
+ struct nf_nat_range2 range;
+ enum ip_conntrack_info ctinfo;
+ struct nf_conn *ct;
+
+ ct = nf_ct_get(skb, &ctinfo);
+ WARN_ON(!(ct != NULL &&
+ (ctinfo == IP_CT_NEW || ctinfo == IP_CT_RELATED ||
+ ctinfo == IP_CT_RELATED_REPLY)));
+
+ xt_nat_convert_range(&range, &mr->range[0]);
+ return nf_nat_setup_info(ct, &range, NF_NAT_MANIP_SRC);
+}
+
+static unsigned int
+xt_dnat_target_v0(struct sk_buff *skb, const struct xt_action_param *par)
+{
+ const struct nf_nat_ipv4_multi_range_compat *mr = par->targinfo;
+ struct nf_nat_range2 range;
+ enum ip_conntrack_info ctinfo;
+ struct nf_conn *ct;
+
+ ct = nf_ct_get(skb, &ctinfo);
+ WARN_ON(!(ct != NULL &&
+ (ctinfo == IP_CT_NEW || ctinfo == IP_CT_RELATED)));
+
+ xt_nat_convert_range(&range, &mr->range[0]);
+ return nf_nat_setup_info(ct, &range, NF_NAT_MANIP_DST);
+}
+
+static unsigned int
+xt_snat_target_v1(struct sk_buff *skb, const struct xt_action_param *par)
+{
+ const struct nf_nat_range *range_v1 = par->targinfo;
+ struct nf_nat_range2 range;
+ enum ip_conntrack_info ctinfo;
+ struct nf_conn *ct;
+
+ ct = nf_ct_get(skb, &ctinfo);
+ WARN_ON(!(ct != NULL &&
+ (ctinfo == IP_CT_NEW || ctinfo == IP_CT_RELATED ||
+ ctinfo == IP_CT_RELATED_REPLY)));
+
+ memcpy(&range, range_v1, sizeof(*range_v1));
+ memset(&range.base_proto, 0, sizeof(range.base_proto));
+
+ return nf_nat_setup_info(ct, &range, NF_NAT_MANIP_SRC);
+}
+
+static unsigned int
+xt_dnat_target_v1(struct sk_buff *skb, const struct xt_action_param *par)
+{
+ const struct nf_nat_range *range_v1 = par->targinfo;
+ struct nf_nat_range2 range;
+ enum ip_conntrack_info ctinfo;
+ struct nf_conn *ct;
+
+ ct = nf_ct_get(skb, &ctinfo);
+ WARN_ON(!(ct != NULL &&
+ (ctinfo == IP_CT_NEW || ctinfo == IP_CT_RELATED)));
+
+ memcpy(&range, range_v1, sizeof(*range_v1));
+ memset(&range.base_proto, 0, sizeof(range.base_proto));
+
+ return nf_nat_setup_info(ct, &range, NF_NAT_MANIP_DST);
+}
+
+static unsigned int
+xt_snat_target_v2(struct sk_buff *skb, const struct xt_action_param *par)
+{
+ const struct nf_nat_range2 *range = par->targinfo;
+ enum ip_conntrack_info ctinfo;
+ struct nf_conn *ct;
+
+ ct = nf_ct_get(skb, &ctinfo);
+ WARN_ON(!(ct != NULL &&
+ (ctinfo == IP_CT_NEW || ctinfo == IP_CT_RELATED ||
+ ctinfo == IP_CT_RELATED_REPLY)));
+
+ return nf_nat_setup_info(ct, range, NF_NAT_MANIP_SRC);
+}
+
+static unsigned int
+xt_dnat_target_v2(struct sk_buff *skb, const struct xt_action_param *par)
+{
+ const struct nf_nat_range2 *range = par->targinfo;
+ enum ip_conntrack_info ctinfo;
+ struct nf_conn *ct;
+
+ ct = nf_ct_get(skb, &ctinfo);
+ WARN_ON(!(ct != NULL &&
+ (ctinfo == IP_CT_NEW || ctinfo == IP_CT_RELATED)));
+
+ return nf_nat_setup_info(ct, range, NF_NAT_MANIP_DST);
+}
+
+static struct xt_target xt_nat_target_reg[] __read_mostly = {
+ {
+ .name = "SNAT",
+ .revision = 0,
+ .checkentry = xt_nat_checkentry_v0,
+ .destroy = xt_nat_destroy,
+ .target = xt_snat_target_v0,
+ .targetsize = sizeof(struct nf_nat_ipv4_multi_range_compat),
+ .family = NFPROTO_IPV4,
+ .table = "nat",
+ .hooks = (1 << NF_INET_POST_ROUTING) |
+ (1 << NF_INET_LOCAL_IN),
+ .me = THIS_MODULE,
+ },
+ {
+ .name = "DNAT",
+ .revision = 0,
+ .checkentry = xt_nat_checkentry_v0,
+ .destroy = xt_nat_destroy,
+ .target = xt_dnat_target_v0,
+ .targetsize = sizeof(struct nf_nat_ipv4_multi_range_compat),
+ .family = NFPROTO_IPV4,
+ .table = "nat",
+ .hooks = (1 << NF_INET_PRE_ROUTING) |
+ (1 << NF_INET_LOCAL_OUT),
+ .me = THIS_MODULE,
+ },
+ {
+ .name = "SNAT",
+ .revision = 1,
+ .checkentry = xt_nat_checkentry,
+ .destroy = xt_nat_destroy,
+ .target = xt_snat_target_v1,
+ .targetsize = sizeof(struct nf_nat_range),
+ .table = "nat",
+ .hooks = (1 << NF_INET_POST_ROUTING) |
+ (1 << NF_INET_LOCAL_IN),
+ .me = THIS_MODULE,
+ },
+ {
+ .name = "DNAT",
+ .revision = 1,
+ .checkentry = xt_nat_checkentry,
+ .destroy = xt_nat_destroy,
+ .target = xt_dnat_target_v1,
+ .targetsize = sizeof(struct nf_nat_range),
+ .table = "nat",
+ .hooks = (1 << NF_INET_PRE_ROUTING) |
+ (1 << NF_INET_LOCAL_OUT),
+ .me = THIS_MODULE,
+ },
+ {
+ .name = "SNAT",
+ .revision = 2,
+ .checkentry = xt_nat_checkentry,
+ .destroy = xt_nat_destroy,
+ .target = xt_snat_target_v2,
+ .targetsize = sizeof(struct nf_nat_range2),
+ .table = "nat",
+ .hooks = (1 << NF_INET_POST_ROUTING) |
+ (1 << NF_INET_LOCAL_IN),
+ .me = THIS_MODULE,
+ },
+ {
+ .name = "DNAT",
+ .revision = 2,
+ .checkentry = xt_nat_checkentry,
+ .destroy = xt_nat_destroy,
+ .target = xt_dnat_target_v2,
+ .targetsize = sizeof(struct nf_nat_range2),
+ .table = "nat",
+ .hooks = (1 << NF_INET_PRE_ROUTING) |
+ (1 << NF_INET_LOCAL_OUT),
+ .me = THIS_MODULE,
+ },
+};
+
+static int __init xt_nat_init(void)
+{
+ return xt_register_targets(xt_nat_target_reg,
+ ARRAY_SIZE(xt_nat_target_reg));
+}
+
+static void __exit xt_nat_exit(void)
+{
+ xt_unregister_targets(xt_nat_target_reg, ARRAY_SIZE(xt_nat_target_reg));
+}
+
+module_init(xt_nat_init);
+module_exit(xt_nat_exit);
+
+MODULE_LICENSE("GPL");
+MODULE_AUTHOR("Patrick McHardy <kaber@trash.net>");
+MODULE_ALIAS("ipt_SNAT");
+MODULE_ALIAS("ipt_DNAT");
+MODULE_ALIAS("ip6t_SNAT");
+MODULE_ALIAS("ip6t_DNAT");
+MODULE_DESCRIPTION("SNAT and DNAT targets support");
generated by cgit v1.2.3 (git 2.39.1) at 2024-06-02 01:32:35 +0000