1 files changed, 119 insertions, 0 deletions
diff --git a/include/net/netfilter/nf_nat.h b/include/net/netfilter/nf_nat.h
new file mode 100644
index 000000000..9877f0645
--- /dev/null
+++ b/include/net/netfilter/nf_nat.h
@@ -0,0 +1,119 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+#ifndef _NF_NAT_H
+#define _NF_NAT_H
+
+#include <linux/list.h>
+#include <linux/netfilter_ipv4.h>
+#include <linux/netfilter/nf_conntrack_pptp.h>
+#include <net/netfilter/nf_conntrack.h>
+#include <net/netfilter/nf_conntrack_extend.h>
+#include <net/netfilter/nf_conntrack_tuple.h>
+#include <uapi/linux/netfilter/nf_nat.h>
+
+enum nf_nat_manip_type {
+	NF_NAT_MANIP_SRC,
+	NF_NAT_MANIP_DST
+};
+
+/* SRC manip occurs POST_ROUTING or LOCAL_IN */
+#define HOOK2MANIP(hooknum) ((hooknum) != NF_INET_POST_ROUTING && \
+			     (hooknum) != NF_INET_LOCAL_IN)
+
+/* per conntrack: nat application helper private data */
+union nf_conntrack_nat_help {
+	/* insert nat helper private data here */
+#if IS_ENABLED(CONFIG_NF_NAT_PPTP)
+	struct nf_nat_pptp nat_pptp_info;
+#endif
+};
+
+/* The structure embedded in the conntrack structure. */
+struct nf_conn_nat {
+	union nf_conntrack_nat_help help;
+#if IS_ENABLED(CONFIG_NF_NAT_MASQUERADE)
+	int masq_index;
+#endif
+};
+
+/* Set up the info structure to map into this range. */
+unsigned int nf_nat_setup_info(struct nf_conn *ct,
+			       const struct nf_nat_range2 *range,
+			       enum nf_nat_manip_type maniptype);
+
+extern unsigned int nf_nat_alloc_null_binding(struct nf_conn *ct,
+					      unsigned int hooknum);
+
+struct nf_conn_nat *nf_ct_nat_ext_add(struct nf_conn *ct);
+
+static inline struct nf_conn_nat *nfct_nat(const struct nf_conn *ct)
+{
+#if IS_ENABLED(CONFIG_NF_NAT)
+	return nf_ct_ext_find(ct, NF_CT_EXT_NAT);
+#else
+	return NULL;
+#endif
+}
+
+static inline bool nf_nat_oif_changed(unsigned int hooknum,
+				      enum ip_conntrack_info ctinfo,
+				      struct nf_conn_nat *nat,
+				      const struct net_device *out)
+{
+#if IS_ENABLED(CONFIG_NF_NAT_MASQUERADE)
+	return nat && nat->masq_index && hooknum == NF_INET_POST_ROUTING &&
+	       CTINFO2DIR(ctinfo) == IP_CT_DIR_ORIGINAL &&
+	       nat->masq_index != out->ifindex;
+#else
+	return false;
+#endif
+}
+
+int nf_nat_register_fn(struct net *net, u8 pf, const struct nf_hook_ops *ops,
+		       const struct nf_hook_ops *nat_ops, unsigned int ops_count);
+void nf_nat_unregister_fn(struct net *net, u8 pf, const struct nf_hook_ops *ops,
+			  unsigned int ops_count);
+
+unsigned int nf_nat_packet(struct nf_conn *ct, enum ip_conntrack_info ctinfo,
+			   unsigned int hooknum, struct sk_buff *skb);
+
+unsigned int nf_nat_manip_pkt(struct sk_buff *skb, struct nf_conn *ct,
+			      enum nf_nat_manip_type mtype,
+			      enum ip_conntrack_dir dir);
+void nf_nat_csum_recalc(struct sk_buff *skb,
+			u8 nfproto, u8 proto, void *data, __sum16 *check,
+			int datalen, int oldlen);
+
+int nf_nat_icmp_reply_translation(struct sk_buff *skb, struct nf_conn *ct,
+				  enum ip_conntrack_info ctinfo,
+				  unsigned int hooknum);
+
+int nf_nat_icmpv6_reply_translation(struct sk_buff *skb, struct nf_conn *ct,
+				    enum ip_conntrack_info ctinfo,
+				    unsigned int hooknum, unsigned int hdrlen);
+
+int nf_nat_ipv4_register_fn(struct net *net, const struct nf_hook_ops *ops);
+void nf_nat_ipv4_unregister_fn(struct net *net, const struct nf_hook_ops *ops);
+
+int nf_nat_ipv6_register_fn(struct net *net, const struct nf_hook_ops *ops);
+void nf_nat_ipv6_unregister_fn(struct net *net, const struct nf_hook_ops *ops);
+
+int nf_nat_inet_register_fn(struct net *net, const struct nf_hook_ops *ops);
+void nf_nat_inet_unregister_fn(struct net *net, const struct nf_hook_ops *ops);
+
+unsigned int
+nf_nat_inet_fn(void *priv, struct sk_buff *skb,
+	       const struct nf_hook_state *state);
+
+int nf_ct_nat(struct sk_buff *skb, struct nf_conn *ct,
+	      enum ip_conntrack_info ctinfo, int *action,
+	      const struct nf_nat_range2 *range, bool commit);
+
+static inline int nf_nat_initialized(const struct nf_conn *ct,
+				     enum nf_nat_manip_type manip)
+{
+	if (manip == NF_NAT_MANIP_SRC)
+		return ct->status & IPS_SRC_NAT_DONE;
+	else
+		return ct->status & IPS_DST_NAT_DONE;
+}
+#endif