include/net/netfilter/nf_nat.h
Source file repositories/reference/linux-study-clean/include/net/netfilter/nf_nat.h
File Facts
- System
- Linux kernel
- Corpus path
include/net/netfilter/nf_nat.h- Extension
.h- Size
- 3864 bytes
- Lines
- 120
- Domain
- Networking Core
- Bucket
- Sockets, Protocols, Packet Path, And Network Policy
- Inferred role
- Networking Core: implementation source
- Status
- source implementation candidate
Why This File Exists
Networking stack implementation surface: socket APIs, protocol dispatch, packet flow, routing, filtering, and network namespaces.
- Networking stack implementation surface: socket APIs, protocol dispatch, packet flow, routing, filtering, and network namespaces.
- Defines or uses C structs; map object ownership, embedded links, reference counts, and lock ownership.
Dependency Surface
linux/list.hlinux/netfilter_ipv4.hlinux/netfilter/nf_conntrack_pptp.hnet/netfilter/nf_conntrack.hnet/netfilter/nf_conntrack_extend.hnet/netfilter/nf_conntrack_tuple.huapi/linux/netfilter/nf_nat.h
Detected Declarations
struct nf_conn_natenum nf_nat_manip_typefunction nf_nat_oif_changedfunction nf_nat_initialized
Annotated Snippet
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
Annotation
- Immediate include surface: `linux/list.h`, `linux/netfilter_ipv4.h`, `linux/netfilter/nf_conntrack_pptp.h`, `net/netfilter/nf_conntrack.h`, `net/netfilter/nf_conntrack_extend.h`, `net/netfilter/nf_conntrack_tuple.h`, `uapi/linux/netfilter/nf_nat.h`.
- Detected declarations: `struct nf_conn_nat`, `enum nf_nat_manip_type`, `function nf_nat_oif_changed`, `function nf_nat_initialized`.
- Atlas domain: Networking Core / Sockets, Protocols, Packet Path, And Network Policy.
- Implementation status: source implementation candidate.
Implementation Notes
- This generated page is the file-by-file coverage layer; curated subsystem chapters should link here when they synthesize a multi-file control flow.
- Core OS pages should be promoted from atlas-only to deep-reviewed when they explain data structures, invariants, locking, lifecycle, and C implementation snippets.
- Driver-family pages are intentionally pattern-oriented unless they are part of the selected PCIe/NVMe representative device path.