1 /* SPDX-License-Identifier: GPL-2.0 */
5 #include <linux/list.h>
6 #include <linux/netfilter_ipv4.h>
7 #include <linux/netfilter/nf_conntrack_pptp.h>
8 #include <net/netfilter/nf_conntrack.h>
9 #include <net/netfilter/nf_conntrack_extend.h>
10 #include <net/netfilter/nf_conntrack_tuple.h>
11 #include <uapi/linux/netfilter/nf_nat.h>
13 enum nf_nat_manip_type {
18 /* SRC manip occurs POST_ROUTING or LOCAL_IN */
19 #define HOOK2MANIP(hooknum) ((hooknum) != NF_INET_POST_ROUTING && \
20 (hooknum) != NF_INET_LOCAL_IN)
22 /* per conntrack: nat application helper private data */
23 union nf_conntrack_nat_help {
24 /* insert nat helper private data here */
25 #if IS_ENABLED(CONFIG_NF_NAT_PPTP)
26 struct nf_nat_pptp nat_pptp_info;
30 /* The structure embedded in the conntrack structure. */
32 union nf_conntrack_nat_help help;
33 #if IS_ENABLED(CONFIG_NF_NAT_MASQUERADE)
38 /* Set up the info structure to map into this range. */
39 unsigned int nf_nat_setup_info(struct nf_conn *ct,
40 const struct nf_nat_range2 *range,
41 enum nf_nat_manip_type maniptype);
43 extern unsigned int nf_nat_alloc_null_binding(struct nf_conn *ct,
44 unsigned int hooknum);
46 struct nf_conn_nat *nf_ct_nat_ext_add(struct nf_conn *ct);
48 static inline struct nf_conn_nat *nfct_nat(const struct nf_conn *ct)
50 #if IS_ENABLED(CONFIG_NF_NAT)
51 return nf_ct_ext_find(ct, NF_CT_EXT_NAT);
57 static inline bool nf_nat_oif_changed(unsigned int hooknum,
58 enum ip_conntrack_info ctinfo,
59 struct nf_conn_nat *nat,
60 const struct net_device *out)
62 #if IS_ENABLED(CONFIG_NF_NAT_MASQUERADE)
63 return nat && nat->masq_index && hooknum == NF_INET_POST_ROUTING &&
64 CTINFO2DIR(ctinfo) == IP_CT_DIR_ORIGINAL &&
65 nat->masq_index != out->ifindex;
71 int nf_nat_register_fn(struct net *net, u8 pf, const struct nf_hook_ops *ops,
72 const struct nf_hook_ops *nat_ops, unsigned int ops_count);
73 void nf_nat_unregister_fn(struct net *net, u8 pf, const struct nf_hook_ops *ops,
74 unsigned int ops_count);
76 unsigned int nf_nat_packet(struct nf_conn *ct, enum ip_conntrack_info ctinfo,
77 unsigned int hooknum, struct sk_buff *skb);
79 unsigned int nf_nat_manip_pkt(struct sk_buff *skb, struct nf_conn *ct,
80 enum nf_nat_manip_type mtype,
81 enum ip_conntrack_dir dir);
82 void nf_nat_csum_recalc(struct sk_buff *skb,
83 u8 nfproto, u8 proto, void *data, __sum16 *check,
84 int datalen, int oldlen);
86 int nf_nat_icmp_reply_translation(struct sk_buff *skb, struct nf_conn *ct,
87 enum ip_conntrack_info ctinfo,
88 unsigned int hooknum);
90 int nf_nat_icmpv6_reply_translation(struct sk_buff *skb, struct nf_conn *ct,
91 enum ip_conntrack_info ctinfo,
92 unsigned int hooknum, unsigned int hdrlen);
94 int nf_nat_ipv4_register_fn(struct net *net, const struct nf_hook_ops *ops);
95 void nf_nat_ipv4_unregister_fn(struct net *net, const struct nf_hook_ops *ops);
97 int nf_nat_ipv6_register_fn(struct net *net, const struct nf_hook_ops *ops);
98 void nf_nat_ipv6_unregister_fn(struct net *net, const struct nf_hook_ops *ops);
100 int nf_nat_inet_register_fn(struct net *net, const struct nf_hook_ops *ops);
101 void nf_nat_inet_unregister_fn(struct net *net, const struct nf_hook_ops *ops);
104 nf_nat_inet_fn(void *priv, struct sk_buff *skb,
105 const struct nf_hook_state *state);
107 int nf_ct_nat(struct sk_buff *skb, struct nf_conn *ct,
108 enum ip_conntrack_info ctinfo, int *action,
109 const struct nf_nat_range2 *range, bool commit);
111 static inline int nf_nat_initialized(const struct nf_conn *ct,
112 enum nf_nat_manip_type manip)
114 if (manip == NF_NAT_MANIP_SRC)
115 return ct->status & IPS_SRC_NAT_DONE;
117 return ct->status & IPS_DST_NAT_DONE;