linux/include/net/ip.h

/* SPDX-License-Identifier: GPL-2.0-or-later */
/*
 * INET		An implementation of the TCP/IP protocol suite for the LINUX
 *		operating system.  INET is implemented using the  BSD Socket
 *		interface as the means of communication with the user level.
 *
 *		Definitions for the IP module.
 *
 * Version:	@(#)ip.h	1.0.2	05/07/93
 *
 * Authors:	Ross Biro
 *		Fred N. van Kempen, <[email protected]>
 *		Alan Cox, <[email protected]>
 *
 * Changes:
 *		Mike McLagan    :       Routing by source
 */
#ifndef _IP_H
#define _IP_H

#include <linux/types.h>
#include <linux/ip.h>
#include <linux/in.h>
#include <linux/skbuff.h>
#include <linux/jhash.h>
#include <linux/sockptr.h>
#include <linux/static_key.h>

#include <net/inet_sock.h>
#include <net/route.h>
#include <net/snmp.h>
#include <net/flow.h>
#include <net/flow_dissector.h>
#include <net/netns/hash.h>
#include <net/lwtunnel.h>
#include <net/inet_dscp.h>

#define IPV4_MAX_PMTU
#define IPV4_MIN_MTU

extern unsigned int sysctl_fib_sync_mem;
extern unsigned int sysctl_fib_sync_mem_min;
extern unsigned int sysctl_fib_sync_mem_max;

struct sock;

struct inet_skb_parm {};

static inline bool ipv4_l3mdev_skb(u16 flags)
{}

static inline unsigned int ip_hdrlen(const struct sk_buff *skb)
{}

struct ipcm_cookie {};

static inline void ipcm_init(struct ipcm_cookie *ipcm)
{}

static inline void ipcm_init_sk(struct ipcm_cookie *ipcm,
				const struct inet_sock *inet)
{}

#define IPCB(skb)
#define PKTINFO_SKB_CB(skb)

/* return enslaved device index if relevant */
static inline int inet_sdif(const struct sk_buff *skb)
{}

/* Special input handler for packets caught by router alert option.
   They are selected only by protocol field, and then processed likely
   local ones; but only if someone wants them! Otherwise, router
   not running rsvpd will kill RSVP.

   It is user level problem, what it will make with them.
   I have no idea, how it will masquearde or NAT them (it is joke, joke :-)),
   but receiver should be enough clever f.e. to forward mtrace requests,
   sent to multicast group to reach destination designated router.
 */

struct ip_ra_chain {};

/* IP flags. */
#define IP_CE
#define IP_DF
#define IP_MF
#define IP_OFFSET

#define IP_FRAG_TIME

struct msghdr;
struct net_device;
struct packet_type;
struct rtable;
struct sockaddr;

int igmp_mc_init(void);

/*
 *	Functions provided by ip.c
 */

int ip_build_and_send_pkt(struct sk_buff *skb, const struct sock *sk,
			  __be32 saddr, __be32 daddr,
			  struct ip_options_rcu *opt, u8 tos);
int ip_rcv(struct sk_buff *skb, struct net_device *dev, struct packet_type *pt,
	   struct net_device *orig_dev);
void ip_list_rcv(struct list_head *head, struct packet_type *pt,
		 struct net_device *orig_dev);
int ip_local_deliver(struct sk_buff *skb);
void ip_protocol_deliver_rcu(struct net *net, struct sk_buff *skb, int proto);
int ip_mr_input(struct sk_buff *skb);
int ip_output(struct net *net, struct sock *sk, struct sk_buff *skb);
int ip_mc_output(struct net *net, struct sock *sk, struct sk_buff *skb);
int ip_do_fragment(struct net *net, struct sock *sk, struct sk_buff *skb,
		   int (*output)(struct net *, struct sock *, struct sk_buff *));

struct ip_fraglist_iter {};

void ip_fraglist_init(struct sk_buff *skb, struct iphdr *iph,
		      unsigned int hlen, struct ip_fraglist_iter *iter);
void ip_fraglist_prepare(struct sk_buff *skb, struct ip_fraglist_iter *iter);

static inline struct sk_buff *ip_fraglist_next(struct ip_fraglist_iter *iter)
{}

struct ip_frag_state {};

void ip_frag_init(struct sk_buff *skb, unsigned int hlen, unsigned int ll_rs,
		  unsigned int mtu, bool DF, struct ip_frag_state *state);
struct sk_buff *ip_frag_next(struct sk_buff *skb,
			     struct ip_frag_state *state);

void ip_send_check(struct iphdr *ip);
int __ip_local_out(struct net *net, struct sock *sk, struct sk_buff *skb);
int ip_local_out(struct net *net, struct sock *sk, struct sk_buff *skb);

int __ip_queue_xmit(struct sock *sk, struct sk_buff *skb, struct flowi *fl,
		    __u8 tos);
void ip_init(void);
int ip_append_data(struct sock *sk, struct flowi4 *fl4,
		   int getfrag(void *from, char *to, int offset, int len,
			       int odd, struct sk_buff *skb),
		   void *from, int len, int protolen,
		   struct ipcm_cookie *ipc,
		   struct rtable **rt,
		   unsigned int flags);
int ip_generic_getfrag(void *from, char *to, int offset, int len, int odd,
		       struct sk_buff *skb);
struct sk_buff *__ip_make_skb(struct sock *sk, struct flowi4 *fl4,
			      struct sk_buff_head *queue,
			      struct inet_cork *cork);
int ip_send_skb(struct net *net, struct sk_buff *skb);
int ip_push_pending_frames(struct sock *sk, struct flowi4 *fl4);
void ip_flush_pending_frames(struct sock *sk);
struct sk_buff *ip_make_skb(struct sock *sk, struct flowi4 *fl4,
			    int getfrag(void *from, char *to, int offset,
					int len, int odd, struct sk_buff *skb),
			    void *from, int length, int transhdrlen,
			    struct ipcm_cookie *ipc, struct rtable **rtp,
			    struct inet_cork *cork, unsigned int flags);

int ip_queue_xmit(struct sock *sk, struct sk_buff *skb, struct flowi *fl);

static inline struct sk_buff *ip_finish_skb(struct sock *sk, struct flowi4 *fl4)
{}

/* Get the route scope that should be used when sending a packet. */
static inline u8 ip_sendmsg_scope(const struct inet_sock *inet,
				  const struct ipcm_cookie *ipc,
				  const struct msghdr *msg)
{}

static inline __u8 get_rttos(struct ipcm_cookie* ipc, struct inet_sock *inet)
{}

/* datagram.c */
int __ip4_datagram_connect(struct sock *sk, struct sockaddr *uaddr, int addr_len);
int ip4_datagram_connect(struct sock *sk, struct sockaddr *uaddr, int addr_len);

void ip4_datagram_release_cb(struct sock *sk);

struct ip_reply_arg {};

#define IP_REPLY_ARG_NOSRCCHECK

static inline __u8 ip_reply_arg_flowi_flags(const struct ip_reply_arg *arg)
{}

void ip_send_unicast_reply(struct sock *sk, struct sk_buff *skb,
			   const struct ip_options *sopt,
			   __be32 daddr, __be32 saddr,
			   const struct ip_reply_arg *arg,
			   unsigned int len, u64 transmit_time, u32 txhash);

#define IP_INC_STATS(net, field)
#define __IP_INC_STATS(net, field)
#define IP_ADD_STATS(net, field, val)
#define __IP_ADD_STATS(net, field, val)
#define IP_UPD_PO_STATS(net, field, val)
#define __IP_UPD_PO_STATS(net, field, val)
#define NET_INC_STATS(net, field)
#define __NET_INC_STATS(net, field)
#define NET_ADD_STATS(net, field, adnd)
#define __NET_ADD_STATS(net, field, adnd)

static inline u64 snmp_get_cpu_field(void __percpu *mib, int cpu, int offt)
{}

unsigned long snmp_fold_field(void __percpu *mib, int offt);
#if BITS_PER_LONG==32
u64 snmp_get_cpu_field64(void __percpu *mib, int cpu, int offct,
			 size_t syncp_offset);
u64 snmp_fold_field64(void __percpu *mib, int offt, size_t sync_off);
#else
static inline u64  snmp_get_cpu_field64(void __percpu *mib, int cpu, int offct,
					size_t syncp_offset)
{}

static inline u64 snmp_fold_field64(void __percpu *mib, int offt, size_t syncp_off)
{}
#endif

#define snmp_get_cpu_field64_batch(buff64, stats_list, mib_statistic, offset)

#define snmp_get_cpu_field_batch(buff, stats_list, mib_statistic)

static inline void inet_get_local_port_range(const struct net *net, int *low, int *high)
{}
bool inet_sk_get_local_port_range(const struct sock *sk, int *low, int *high);

#ifdef CONFIG_SYSCTL
static inline bool inet_is_local_reserved_port(struct net *net, unsigned short port)
{}

static inline bool sysctl_dev_name_is_allowed(const char *name)
{}

static inline bool inet_port_requires_bind_service(struct net *net, unsigned short port)
{}

#else
static inline bool inet_is_local_reserved_port(struct net *net, unsigned short port)
{
	return false;
}

static inline bool inet_port_requires_bind_service(struct net *net, unsigned short port)
{
	return port < PROT_SOCK;
}
#endif

__be32 inet_current_timestamp(void);

/* From inetpeer.c */
extern int inet_peer_threshold;
extern int inet_peer_minttl;
extern int inet_peer_maxttl;

void ipfrag_init(void);

void ip_static_sysctl_init(void);

#define IP4_REPLY_MARK(net, mark)

static inline bool ip_is_fragment(const struct iphdr *iph)
{}

#ifdef CONFIG_INET
#include <net/dst.h>

/* The function in 2.2 was invalid, producing wrong result for
 * check=0xFEFF. It was noticed by Arthur Skawina _year_ ago. --ANK(000625) */
static inline
int ip_decrease_ttl(struct iphdr *iph)
{}

static inline int ip_mtu_locked(const struct dst_entry *dst)
{}

static inline
int ip_dont_fragment(const struct sock *sk, const struct dst_entry *dst)
{}

static inline bool ip_sk_accept_pmtu(const struct sock *sk)
{}

static inline bool ip_sk_use_pmtu(const struct sock *sk)
{}

static inline bool ip_sk_ignore_df(const struct sock *sk)
{}

static inline unsigned int ip_dst_mtu_maybe_forward(const struct dst_entry *dst,
						    bool forwarding)
{}

static inline unsigned int ip_skb_dst_mtu(struct sock *sk,
					  const struct sk_buff *skb)
{}

struct dst_metrics *ip_fib_metrics_init(struct nlattr *fc_mx, int fc_mx_len,
					struct netlink_ext_ack *extack);
static inline void ip_fib_metrics_put(struct dst_metrics *fib_metrics)
{}

/* ipv4 and ipv6 both use refcounted metrics if it is not the default */
static inline
void ip_dst_init_metrics(struct dst_entry *dst, struct dst_metrics *fib_metrics)
{}

static inline
void ip_dst_metrics_put(struct dst_entry *dst)
{}

void __ip_select_ident(struct net *net, struct iphdr *iph, int segs);

static inline void ip_select_ident_segs(struct net *net, struct sk_buff *skb,
					struct sock *sk, int segs)
{}

static inline void ip_select_ident(struct net *net, struct sk_buff *skb,
				   struct sock *sk)
{}

static inline __wsum inet_compute_pseudo(struct sk_buff *skb, int proto)
{}

/* copy IPv4 saddr & daddr to flow_keys, possibly using 64bit load/store
 * Equivalent to :	flow->v4addrs.src = iph->saddr;
 *			flow->v4addrs.dst = iph->daddr;
 */
static inline void iph_to_flow_copy_v4addrs(struct flow_keys *flow,
					    const struct iphdr *iph)
{}

/*
 *	Map a multicast IP onto multicast MAC for type ethernet.
 */

static inline void ip_eth_mc_map(__be32 naddr, char *buf)
{}

/*
 *	Map a multicast IP onto multicast MAC for type IP-over-InfiniBand.
 *	Leave P_Key as 0 to be filled in by driver.
 */

static inline void ip_ib_mc_map(__be32 naddr, const unsigned char *broadcast, char *buf)
{}

static inline void ip_ipgre_mc_map(__be32 naddr, const unsigned char *broadcast, char *buf)
{}

#if IS_ENABLED(CONFIG_IPV6)
#include <linux/ipv6.h>
#endif

static __inline__ void inet_reset_saddr(struct sock *sk)
{}

#endif

static inline unsigned int ipv4_addr_hash(__be32 ip)
{}

static inline u32 ipv4_portaddr_hash(const struct net *net,
				     __be32 saddr,
				     unsigned int port)
{}

bool ip_call_ra_chain(struct sk_buff *skb);

/*
 *	Functions provided by ip_fragment.c
 */

enum ip_defrag_users {};

/* Return true if the value of 'user' is between 'lower_bond'
 * and 'upper_bond' inclusively.
 */
static inline bool ip_defrag_user_in_between(u32 user,
					     enum ip_defrag_users lower_bond,
					     enum ip_defrag_users upper_bond)
{}

int ip_defrag(struct net *net, struct sk_buff *skb, u32 user);
#ifdef CONFIG_INET
struct sk_buff *ip_check_defrag(struct net *net, struct sk_buff *skb, u32 user);
#else
static inline struct sk_buff *ip_check_defrag(struct net *net, struct sk_buff *skb, u32 user)
{
	return skb;
}
#endif

/*
 *	Functions provided by ip_forward.c
 */

int ip_forward(struct sk_buff *skb);

/*
 *	Functions provided by ip_options.c
 */

void ip_options_build(struct sk_buff *skb, struct ip_options *opt,
		      __be32 daddr, struct rtable *rt);

int __ip_options_echo(struct net *net, struct ip_options *dopt,
		      struct sk_buff *skb, const struct ip_options *sopt);
static inline int ip_options_echo(struct net *net, struct ip_options *dopt,
				  struct sk_buff *skb)
{}

void ip_options_fragment(struct sk_buff *skb);
int __ip_options_compile(struct net *net, struct ip_options *opt,
			 struct sk_buff *skb, __be32 *info);
int ip_options_compile(struct net *net, struct ip_options *opt,
		       struct sk_buff *skb);
int ip_options_get(struct net *net, struct ip_options_rcu **optp,
		   sockptr_t data, int optlen);
void ip_options_undo(struct ip_options *opt);
void ip_forward_options(struct sk_buff *skb);
int ip_options_rcv_srr(struct sk_buff *skb, struct net_device *dev);

/*
 *	Functions provided by ip_sockglue.c
 */

void ipv4_pktinfo_prepare(const struct sock *sk, struct sk_buff *skb, bool drop_dst);
void ip_cmsg_recv_offset(struct msghdr *msg, struct sock *sk,
			 struct sk_buff *skb, int tlen, int offset);
int ip_cmsg_send(struct sock *sk, struct msghdr *msg,
		 struct ipcm_cookie *ipc, bool allow_ipv6);
DECLARE_STATIC_KEY_FALSE(ip4_min_ttl);
int do_ip_setsockopt(struct sock *sk, int level, int optname, sockptr_t optval,
		     unsigned int optlen);
int ip_setsockopt(struct sock *sk, int level, int optname, sockptr_t optval,
		  unsigned int optlen);
int do_ip_getsockopt(struct sock *sk, int level, int optname,
		     sockptr_t optval, sockptr_t optlen);
int ip_getsockopt(struct sock *sk, int level, int optname, char __user *optval,
		  int __user *optlen);
int ip_ra_control(struct sock *sk, unsigned char on,
		  void (*destructor)(struct sock *));

int ip_recv_error(struct sock *sk, struct msghdr *msg, int len, int *addr_len);
void ip_icmp_error(struct sock *sk, struct sk_buff *skb, int err, __be16 port,
		   u32 info, u8 *payload);
void ip_local_error(struct sock *sk, int err, __be32 daddr, __be16 dport,
		    u32 info);

static inline void ip_cmsg_recv(struct msghdr *msg, struct sk_buff *skb)
{}

bool icmp_global_allow(struct net *net);
void icmp_global_consume(struct net *net);

#ifdef CONFIG_PROC_FS
int ip_misc_proc_init(void);
#endif

int rtm_getroute_parse_ip_proto(struct nlattr *attr, u8 *ip_proto, u8 family,
				struct netlink_ext_ack *extack);

static inline bool inetdev_valid_mtu(unsigned int mtu)
{}

void ip_sock_set_freebind(struct sock *sk);
int ip_sock_set_mtu_discover(struct sock *sk, int val);
void ip_sock_set_pktinfo(struct sock *sk);
void ip_sock_set_recverr(struct sock *sk);
void ip_sock_set_tos(struct sock *sk, int val);
void  __ip_sock_set_tos(struct sock *sk, int val);

#endif	/* _IP_H */