[linux.git] / include / net / ip.h

/*
 * 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
 *
 *		This program is free software; you can redistribute it and/or
 *		modify it under the terms of the GNU General Public License
 *		as published by the Free Software Foundation; either version
 *		2 of the License, or (at your option) any later version.
 */
#ifndef _IP_H
#define _IP_H

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

#include <net/inet_sock.h>
#include <net/snmp.h>
#include <net/flow.h>

struct sock;

struct inet_skb_parm {
	struct ip_options	opt;		/* Compiled IP options		*/
	unsigned char		flags;

#define IPSKB_FORWARDED		1
#define IPSKB_XFRM_TUNNEL_SIZE	2
#define IPSKB_XFRM_TRANSFORMED	4
#define IPSKB_FRAG_COMPLETE	8
#define IPSKB_REROUTED		16

	u16			frag_max_size;
};

static inline unsigned int ip_hdrlen(const struct sk_buff *skb)
{
	return ip_hdr(skb)->ihl * 4;
}

struct ipcm_cookie {
	__be32			addr;
	int			oif;
	struct ip_options_rcu	*opt;
	__u8			tx_flags;
};

#define IPCB(skb) ((struct inet_skb_parm*)((skb)->cb))

struct ip_ra_chain {
	struct ip_ra_chain __rcu *next;
	struct sock		*sk;
	union {
		void			(*destructor)(struct sock *);
		struct sock		*saved_sk;
	};
	struct rcu_head		rcu;
};

extern struct ip_ra_chain __rcu *ip_ra_chain;

/* IP flags. */
#define IP_CE		0x8000		/* Flag: "Congestion"		*/
#define IP_DF		0x4000		/* Flag: "Don't Fragment"	*/
#define IP_MF		0x2000		/* Flag: "More Fragments"	*/
#define IP_OFFSET	0x1FFF		/* "Fragment Offset" part	*/

#define IP_FRAG_TIME	(30 * HZ)		/* fragment lifetime	*/

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

extern int		igmp_mc_proc_init(void);

/*
 *	Functions provided by ip.c
 */

extern int		ip_build_and_send_pkt(struct sk_buff *skb, struct sock *sk,
					      __be32 saddr, __be32 daddr,
					      struct ip_options_rcu *opt);
extern int		ip_rcv(struct sk_buff *skb, struct net_device *dev,
			       struct packet_type *pt, struct net_device *orig_dev);
extern int		ip_local_deliver(struct sk_buff *skb);
extern int		ip_mr_input(struct sk_buff *skb);
extern int		ip_output(struct sk_buff *skb);
extern int		ip_mc_output(struct sk_buff *skb);
extern int		ip_fragment(struct sk_buff *skb, int (*output)(struct sk_buff *));
extern int		ip_do_nat(struct sk_buff *skb);
extern void		ip_send_check(struct iphdr *ip);
extern int		__ip_local_out(struct sk_buff *skb);
extern int		ip_local_out(struct sk_buff *skb);
extern int		ip_queue_xmit(struct sk_buff *skb, struct flowi *fl);
extern void		ip_init(void);
extern 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);
extern int		ip_generic_getfrag(void *from, char *to, int offset, int len, int odd, struct sk_buff *skb);
extern ssize_t		ip_append_page(struct sock *sk, struct flowi4 *fl4, struct page *page,
				int offset, size_t size, int flags);
extern struct sk_buff  *__ip_make_skb(struct sock *sk,
				      struct flowi4 *fl4,
				      struct sk_buff_head *queue,
				      struct inet_cork *cork);
extern int		ip_send_skb(struct net *net, struct sk_buff *skb);
extern int		ip_push_pending_frames(struct sock *sk, struct flowi4 *fl4);
extern void		ip_flush_pending_frames(struct sock *sk);
extern 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,
				    unsigned int flags);

static inline struct sk_buff *ip_finish_skb(struct sock *sk, struct flowi4 *fl4)
{
	return __ip_make_skb(sk, fl4, &sk->sk_write_queue, &inet_sk(sk)->cork.base);
}

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

extern void ip4_datagram_release_cb(struct sock *sk);

struct ip_reply_arg {
	struct kvec iov[1];   
	int	    flags;
	__wsum 	    csum;
	int	    csumoffset; /* u16 offset of csum in iov[0].iov_base */
				/* -1 if not needed */ 
	int	    bound_dev_if;
	u8  	    tos;
}; 

#define IP_REPLY_ARG_NOSRCCHECK 1

static inline __u8 ip_reply_arg_flowi_flags(const struct ip_reply_arg *arg)
{
	return (arg->flags & IP_REPLY_ARG_NOSRCCHECK) ? FLOWI_FLAG_ANYSRC : 0;
}

void ip_send_unicast_reply(struct net *net, struct sk_buff *skb, __be32 daddr,
			   __be32 saddr, const struct ip_reply_arg *arg,
			   unsigned int len);

struct ipv4_config {
	int	log_martians;
	int	no_pmtu_disc;
};

extern struct ipv4_config ipv4_config;
#define IP_INC_STATS(net, field)	SNMP_INC_STATS64((net)->mib.ip_statistics, field)
#define IP_INC_STATS_BH(net, field)	SNMP_INC_STATS64_BH((net)->mib.ip_statistics, field)
#define IP_ADD_STATS(net, field, val)	SNMP_ADD_STATS64((net)->mib.ip_statistics, field, val)
#define IP_ADD_STATS_BH(net, field, val) SNMP_ADD_STATS64_BH((net)->mib.ip_statistics, field, val)
#define IP_UPD_PO_STATS(net, field, val) SNMP_UPD_PO_STATS64((net)->mib.ip_statistics, field, val)
#define IP_UPD_PO_STATS_BH(net, field, val) SNMP_UPD_PO_STATS64_BH((net)->mib.ip_statistics, field, val)
#define NET_INC_STATS(net, field)	SNMP_INC_STATS((net)->mib.net_statistics, field)
#define NET_INC_STATS_BH(net, field)	SNMP_INC_STATS_BH((net)->mib.net_statistics, field)
#define NET_INC_STATS_USER(net, field) 	SNMP_INC_STATS_USER((net)->mib.net_statistics, field)
#define NET_ADD_STATS_BH(net, field, adnd) SNMP_ADD_STATS_BH((net)->mib.net_statistics, field, adnd)
#define NET_ADD_STATS_USER(net, field, adnd) SNMP_ADD_STATS_USER((net)->mib.net_statistics, field, adnd)

extern unsigned long snmp_fold_field(void __percpu *mib[], int offt);
#if BITS_PER_LONG==32
extern u64 snmp_fold_field64(void __percpu *mib[], int offt, size_t sync_off);
#else
static inline u64 snmp_fold_field64(void __percpu *mib[], int offt, size_t syncp_off)
{
	return snmp_fold_field(mib, offt);
}
#endif
extern int snmp_mib_init(void __percpu *ptr[2], size_t mibsize, size_t align);
extern void snmp_mib_free(void __percpu *ptr[2]);

extern struct local_ports {
	seqlock_t	lock;
	int		range[2];
} sysctl_local_ports;
extern void inet_get_local_port_range(int *low, int *high);

extern unsigned long *sysctl_local_reserved_ports;
static inline int inet_is_reserved_local_port(int port)
{
	return test_bit(port, sysctl_local_reserved_ports);
}

extern int sysctl_ip_nonlocal_bind;

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

/* From ip_input.c */
extern int sysctl_ip_early_demux;

/* From ip_output.c */
extern int sysctl_ip_dynaddr;

extern void ipfrag_init(void);

extern void ip_static_sysctl_init(void);

static inline bool ip_is_fragment(const struct iphdr *iph)
{
	return (iph->frag_off & htons(IP_MF | IP_OFFSET)) != 0;
}

#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)
{
	u32 check = (__force u32)iph->check;
	check += (__force u32)htons(0x0100);
	iph->check = (__force __sum16)(check + (check>=0xFFFF));
	return --iph->ttl;
}

static inline
int ip_dont_fragment(struct sock *sk, struct dst_entry *dst)
{
	return  inet_sk(sk)->pmtudisc == IP_PMTUDISC_DO ||
		(inet_sk(sk)->pmtudisc == IP_PMTUDISC_WANT &&
		 !(dst_metric_locked(dst, RTAX_MTU)));
}

extern void __ip_select_ident(struct iphdr *iph, struct dst_entry *dst, int more);

static inline void ip_select_ident(struct iphdr *iph, struct dst_entry *dst, struct sock *sk)
{
	if (iph->frag_off & htons(IP_DF)) {
		/* This is only to work around buggy Windows95/2000
		 * VJ compression implementations.  If the ID field
		 * does not change, they drop every other packet in
		 * a TCP stream using header compression.
		 */
		iph->id = (sk && inet_sk(sk)->inet_daddr) ?
					htons(inet_sk(sk)->inet_id++) : 0;
	} else
		__ip_select_ident(iph, dst, 0);
}

static inline void ip_select_ident_more(struct iphdr *iph, struct dst_entry *dst, struct sock *sk, int more)
{
	if (iph->frag_off & htons(IP_DF)) {
		if (sk && inet_sk(sk)->inet_daddr) {
			iph->id = htons(inet_sk(sk)->inet_id);
			inet_sk(sk)->inet_id += 1 + more;
		} else
			iph->id = 0;
	} else
		__ip_select_ident(iph, dst, more);
}

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

static inline void ip_eth_mc_map(__be32 naddr, char *buf)
{
	__u32 addr=ntohl(naddr);
	buf[0]=0x01;
	buf[1]=0x00;
	buf[2]=0x5e;
	buf[5]=addr&0xFF;
	addr>>=8;
	buf[4]=addr&0xFF;
	addr>>=8;
	buf[3]=addr&0x7F;
}

/*
 *	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)
{
	__u32 addr;
	unsigned char scope = broadcast[5] & 0xF;

	buf[0]  = 0;		/* Reserved */
	buf[1]  = 0xff;		/* Multicast QPN */
	buf[2]  = 0xff;
	buf[3]  = 0xff;
	addr    = ntohl(naddr);
	buf[4]  = 0xff;
	buf[5]  = 0x10 | scope;	/* scope from broadcast address */
	buf[6]  = 0x40;		/* IPv4 signature */
	buf[7]  = 0x1b;
	buf[8]  = broadcast[8];		/* P_Key */
	buf[9]  = broadcast[9];
	buf[10] = 0;
	buf[11] = 0;
	buf[12] = 0;
	buf[13] = 0;
	buf[14] = 0;
	buf[15] = 0;
	buf[19] = addr & 0xff;
	addr  >>= 8;
	buf[18] = addr & 0xff;
	addr  >>= 8;
	buf[17] = addr & 0xff;
	addr  >>= 8;
	buf[16] = addr & 0x0f;
}

static inline void ip_ipgre_mc_map(__be32 naddr, const unsigned char *broadcast, char *buf)
{
	if ((broadcast[0] | broadcast[1] | broadcast[2] | broadcast[3]) != 0)
		memcpy(buf, broadcast, 4);
	else
		memcpy(buf, &naddr, sizeof(naddr));
}

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

static __inline__ void inet_reset_saddr(struct sock *sk)
{
	inet_sk(sk)->inet_rcv_saddr = inet_sk(sk)->inet_saddr = 0;
#if IS_ENABLED(CONFIG_IPV6)
	if (sk->sk_family == PF_INET6) {
		struct ipv6_pinfo *np = inet6_sk(sk);

		memset(&np->saddr, 0, sizeof(np->saddr));
		memset(&np->rcv_saddr, 0, sizeof(np->rcv_saddr));
	}
#endif
}

#endif

static inline int sk_mc_loop(struct sock *sk)
{
	if (!sk)
		return 1;
	switch (sk->sk_family) {
	case AF_INET:
		return inet_sk(sk)->mc_loop;
#if IS_ENABLED(CONFIG_IPV6)
	case AF_INET6:
		return inet6_sk(sk)->mc_loop;
#endif
	}
	WARN_ON(1);
	return 1;
}

extern bool ip_call_ra_chain(struct sk_buff *skb);

/*
 *	Functions provided by ip_fragment.c
 */

enum ip_defrag_users {
	IP_DEFRAG_LOCAL_DELIVER,
	IP_DEFRAG_CALL_RA_CHAIN,
	IP_DEFRAG_CONNTRACK_IN,
	__IP_DEFRAG_CONNTRACK_IN_END	= IP_DEFRAG_CONNTRACK_IN + USHRT_MAX,
	IP_DEFRAG_CONNTRACK_OUT,
	__IP_DEFRAG_CONNTRACK_OUT_END	= IP_DEFRAG_CONNTRACK_OUT + USHRT_MAX,
	IP_DEFRAG_CONNTRACK_BRIDGE_IN,
	__IP_DEFRAG_CONNTRACK_BRIDGE_IN = IP_DEFRAG_CONNTRACK_BRIDGE_IN + USHRT_MAX,
	IP_DEFRAG_VS_IN,
	IP_DEFRAG_VS_OUT,
	IP_DEFRAG_VS_FWD,
	IP_DEFRAG_AF_PACKET,
	IP_DEFRAG_MACVLAN,
};

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

/*
 *	Functions provided by ip_forward.c
 */
 
extern int ip_forward(struct sk_buff *skb);
 
/*
 *	Functions provided by ip_options.c
 */
 
extern void ip_options_build(struct sk_buff *skb, struct ip_options *opt,
			     __be32 daddr, struct rtable *rt, int is_frag);
extern int ip_options_echo(struct ip_options *dopt, struct sk_buff *skb);
extern void ip_options_fragment(struct sk_buff *skb);
extern int ip_options_compile(struct net *net,
			      struct ip_options *opt, struct sk_buff *skb);
extern int ip_options_get(struct net *net, struct ip_options_rcu **optp,
			  unsigned char *data, int optlen);
extern int ip_options_get_from_user(struct net *net, struct ip_options_rcu **optp,
				    unsigned char __user *data, int optlen);
extern void ip_options_undo(struct ip_options * opt);
extern void ip_forward_options(struct sk_buff *skb);
extern int ip_options_rcv_srr(struct sk_buff *skb);

/*
 *	Functions provided by ip_sockglue.c
 */

extern void	ipv4_pktinfo_prepare(struct sk_buff *skb);
extern void	ip_cmsg_recv(struct msghdr *msg, struct sk_buff *skb);
extern int	ip_cmsg_send(struct net *net,
			     struct msghdr *msg, struct ipcm_cookie *ipc);
extern int	ip_setsockopt(struct sock *sk, int level, int optname, char __user *optval, unsigned int optlen);
extern int	ip_getsockopt(struct sock *sk, int level, int optname, char __user *optval, int __user *optlen);
extern int	compat_ip_setsockopt(struct sock *sk, int level,
			int optname, char __user *optval, unsigned int optlen);
extern int	compat_ip_getsockopt(struct sock *sk, int level,
			int optname, char __user *optval, int __user *optlen);
extern int	ip_ra_control(struct sock *sk, unsigned char on, void (*destructor)(struct sock *));

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

#ifdef CONFIG_PROC_FS
extern int ip_misc_proc_init(void);
#endif

#endif	/* _IP_H */
Commit	Line	Data
1da177e4 LT	1	/*
	2	* INET An implementation of the TCP/IP protocol suite for the LINUX
	3	* operating system. INET is implemented using the BSD Socket
	4	* interface as the means of communication with the user level.
	5	*
	6	* Definitions for the IP module.
	7	*
	8	* Version: @(#)ip.h 1.0.2 05/07/93
	9	*
02c30a84	10	* Authors: Ross Biro
1da177e4 LT	11	* Fred N. van Kempen, <[email protected]>
	12	* Alan Cox, <[email protected]>
	13	*
	14	* Changes:
	15	* Mike McLagan : Routing by source
	16	*
	17	* This program is free software; you can redistribute it and/or
	18	* modify it under the terms of the GNU General Public License
	19	* as published by the Free Software Foundation; either version
	20	* 2 of the License, or (at your option) any later version.
	21	*/
	22	#ifndef _IP_H
	23	#define _IP_H
	24
1da177e4	25	#include <linux/types.h>
1da177e4 LT	26	#include <linux/ip.h>
1da177e4 LT	27	#include <linux/in.h>
c9bdd4b5	28	#include <linux/skbuff.h>
14c85021 ACM	29
14c85021 ACM	30	#include <net/inet_sock.h>
1da177e4	31	#include <net/snmp.h>
86b08d86	32	#include <net/flow.h>
1da177e4 LT	33
	34	struct sock;
	35
fd2c3ef7	36	struct inet_skb_parm {
1da177e4 LT	37	struct ip_options opt; /* Compiled IP options */
	38	unsigned char flags;
	39
8cdfab8a PM	40	#define IPSKB_FORWARDED 1
8cdfab8a PM	41	#define IPSKB_XFRM_TUNNEL_SIZE 2
3e3850e9 PM	42	#define IPSKB_XFRM_TRANSFORMED 4
3e3850e9 PM	43	#define IPSKB_FRAG_COMPLETE 8
48d5cad8	44	#define IPSKB_REROUTED 16
5f2d04f1 PM	45
5f2d04f1 PM	46	u16 frag_max_size;
1da177e4 LT	47	};
1da177e4 LT	48
c9bdd4b5 ACM	49	static inline unsigned int ip_hdrlen(const struct sk_buff *skb)
c9bdd4b5 ACM	50	{
eddc9ec5	51	return ip_hdr(skb)->ihl * 4;
c9bdd4b5 ACM	52	}
c9bdd4b5 ACM	53
fd2c3ef7	54	struct ipcm_cookie {
c1d18f9f	55	__be32 addr;
1da177e4	56	int oif;
f6d8bd05	57	struct ip_options_rcu *opt;
2244d07b	58	__u8 tx_flags;
1da177e4 LT	59	};
	60
	61	#define IPCB(skb) ((struct inet_skb_parm*)((skb)->cb))
	62
fd2c3ef7	63	struct ip_ra_chain {
43a951e9	64	struct ip_ra_chain __rcu *next;
1da177e4	65	struct sock *sk;
592fcb9d ED	66	union {
	67	void (destructor)(struct sock );
	68	struct sock *saved_sk;
	69	};
66018506	70	struct rcu_head rcu;
1da177e4 LT	71	};
1da177e4 LT	72
43a951e9	73	extern struct ip_ra_chain __rcu *ip_ra_chain;
1da177e4 LT	74
	75	/* IP flags. */
	76	#define IP_CE 0x8000 /* Flag: "Congestion" */
	77	#define IP_DF 0x4000 /* Flag: "Don't Fragment" */
	78	#define IP_MF 0x2000 /* Flag: "More Fragments" */
	79	#define IP_OFFSET 0x1FFF /* "Fragment Offset" part */
	80
	81	#define IP_FRAG_TIME (30 * HZ) /* fragment lifetime */
	82
14c85021 ACM	83	struct msghdr;
	84	struct net_device;
	85	struct packet_type;
	86	struct rtable;
14c85021 ACM	87	struct sockaddr;
14c85021 ACM	88
1da177e4 LT	89	extern int igmp_mc_proc_init(void);
	90
	91	/*
	92	* Functions provided by ip.c
	93	*/
	94
	95	extern int ip_build_and_send_pkt(struct sk_buff skb, struct sock sk,
13d8eaa0	96	__be32 saddr, __be32 daddr,
f6d8bd05	97	struct ip_options_rcu *opt);
1da177e4	98	extern int ip_rcv(struct sk_buff skb, struct net_device dev,
f2ccd8fa	99	struct packet_type pt, struct net_device orig_dev);
1da177e4 LT	100	extern int ip_local_deliver(struct sk_buff *skb);
	101	extern int ip_mr_input(struct sk_buff *skb);
	102	extern int ip_output(struct sk_buff *skb);
	103	extern int ip_mc_output(struct sk_buff *skb);
2e2f7aef	104	extern int ip_fragment(struct sk_buff skb, int (output)(struct sk_buff *));
1da177e4 LT	105	extern int ip_do_nat(struct sk_buff *skb);
1da177e4 LT	106	extern void ip_send_check(struct iphdr *ip);
c439cb2e HX	107	extern int __ip_local_out(struct sk_buff *skb);
c439cb2e HX	108	extern int ip_local_out(struct sk_buff *skb);
d9d8da80	109	extern int ip_queue_xmit(struct sk_buff skb, struct flowi fl);
1da177e4	110	extern void ip_init(void);
f5fca608	111	extern int ip_append_data(struct sock sk, struct flowi4 fl4,
1da177e4 LT	112	int getfrag(void from, char to, int offset, int len,
	113	int odd, struct sk_buff *skb),
	114	void *from, int len, int protolen,
	115	struct ipcm_cookie *ipc,
2e77d89b	116	struct rtable **rt,
1da177e4 LT	117	unsigned int flags);
1da177e4 LT	118	extern int ip_generic_getfrag(void from, char to, int offset, int len, int odd, struct sk_buff *skb);
f5fca608	119	extern ssize_t ip_append_page(struct sock sk, struct flowi4 fl4, struct page *page,
1da177e4	120	int offset, size_t size, int flags);
1c32c5ad	121	extern struct sk_buff __ip_make_skb(struct sock sk,
77968b78	122	struct flowi4 *fl4,
1c32c5ad HX	123	struct sk_buff_head *queue,
1c32c5ad HX	124	struct inet_cork *cork);
b5ec8eea	125	extern int ip_send_skb(struct net net, struct sk_buff skb);
77968b78	126	extern int ip_push_pending_frames(struct sock sk, struct flowi4 fl4);
1da177e4	127	extern void ip_flush_pending_frames(struct sock *sk);
1c32c5ad	128	extern struct sk_buff ip_make_skb(struct sock sk,
77968b78	129	struct flowi4 *fl4,
1c32c5ad HX	130	int getfrag(void from, char to, int offset, int len,
	131	int odd, struct sk_buff *skb),
	132	void *from, int length, int transhdrlen,
	133	struct ipcm_cookie *ipc,
	134	struct rtable **rtp,
	135	unsigned int flags);
	136
77968b78	137	static inline struct sk_buff ip_finish_skb(struct sock sk, struct flowi4 *fl4)
1c32c5ad	138	{
77968b78	139	return __ip_make_skb(sk, fl4, &sk->sk_write_queue, &inet_sk(sk)->cork.base);
1c32c5ad	140	}
1da177e4 LT	141
	142	/* datagram.c */
	143	extern int ip4_datagram_connect(struct sock *sk,
	144	struct sockaddr *uaddr, int addr_len);
	145
8141ed9f SK	146	extern void ip4_datagram_release_cb(struct sock *sk);
8141ed9f SK	147
1da177e4 LT	148	struct ip_reply_arg {
1da177e4 LT	149	struct kvec iov[1];
88ef4a5a	150	int flags;
d6f5493c	151	__wsum csum;
1da177e4 LT	152	int csumoffset; /* u16 offset of csum in iov[0].iov_base */
1da177e4 LT	153	/* -1 if not needed */
f0e48dbf	154	int bound_dev_if;
66b13d99	155	u8 tos;
1da177e4 LT	156	};
1da177e4 LT	157
88ef4a5a KK	158	#define IP_REPLY_ARG_NOSRCCHECK 1
88ef4a5a KK	159
86b08d86 KK	160	static inline __u8 ip_reply_arg_flowi_flags(const struct ip_reply_arg *arg)
	161	{
	162	return (arg->flags & IP_REPLY_ARG_NOSRCCHECK) ? FLOWI_FLAG_ANYSRC : 0;
	163	}
	164
be9f4a44	165	void ip_send_unicast_reply(struct net net, struct sk_buff skb, __be32 daddr,
70e73416 DM	166	__be32 saddr, const struct ip_reply_arg *arg,
70e73416 DM	167	unsigned int len);
1da177e4	168
fd2c3ef7	169	struct ipv4_config {
1da177e4	170	int log_martians;
1da177e4 LT	171	int no_pmtu_disc;
	172	};
	173
	174	extern struct ipv4_config ipv4_config;
4ce3c183 ED	175	#define IP_INC_STATS(net, field) SNMP_INC_STATS64((net)->mib.ip_statistics, field)
	176	#define IP_INC_STATS_BH(net, field) SNMP_INC_STATS64_BH((net)->mib.ip_statistics, field)
	177	#define IP_ADD_STATS(net, field, val) SNMP_ADD_STATS64((net)->mib.ip_statistics, field, val)
	178	#define IP_ADD_STATS_BH(net, field, val) SNMP_ADD_STATS64_BH((net)->mib.ip_statistics, field, val)
	179	#define IP_UPD_PO_STATS(net, field, val) SNMP_UPD_PO_STATS64((net)->mib.ip_statistics, field, val)
	180	#define IP_UPD_PO_STATS_BH(net, field, val) SNMP_UPD_PO_STATS64_BH((net)->mib.ip_statistics, field, val)
61a7e260 PE	181	#define NET_INC_STATS(net, field) SNMP_INC_STATS((net)->mib.net_statistics, field)
	182	#define NET_INC_STATS_BH(net, field) SNMP_INC_STATS_BH((net)->mib.net_statistics, field)
	183	#define NET_INC_STATS_USER(net, field) SNMP_INC_STATS_USER((net)->mib.net_statistics, field)
	184	#define NET_ADD_STATS_BH(net, field, adnd) SNMP_ADD_STATS_BH((net)->mib.net_statistics, field, adnd)
	185	#define NET_ADD_STATS_USER(net, field, adnd) SNMP_ADD_STATS_USER((net)->mib.net_statistics, field, adnd)
1da177e4	186
7d720c3e	187	extern unsigned long snmp_fold_field(void __percpu *mib[], int offt);
4ce3c183 ED	188	#if BITS_PER_LONG==32
	189	extern u64 snmp_fold_field64(void __percpu *mib[], int offt, size_t sync_off);
	190	#else
	191	static inline u64 snmp_fold_field64(void __percpu *mib[], int offt, size_t syncp_off)
	192	{
	193	return snmp_fold_field(mib, offt);
	194	}
	195	#endif
1823e4c8	196	extern int snmp_mib_init(void __percpu *ptr[2], size_t mibsize, size_t align);
7d720c3e	197	extern void snmp_mib_free(void __percpu *ptr[2]);
33490170	198
3c689b73 ED	199	extern struct local_ports {
	200	seqlock_t lock;
	201	int range[2];
	202	} sysctl_local_ports;
227b60f5 SH	203	extern void inet_get_local_port_range(int low, int high);
227b60f5 SH	204
e3826f1e AW	205	extern unsigned long *sysctl_local_reserved_ports;
	206	static inline int inet_is_reserved_local_port(int port)
	207	{
	208	return test_bit(port, sysctl_local_reserved_ports);
	209	}
	210
cdac4e07	211	extern int sysctl_ip_nonlocal_bind;
1da177e4	212
20380731 ACM	213	/* From inetpeer.c */
	214	extern int inet_peer_threshold;
	215	extern int inet_peer_minttl;
	216	extern int inet_peer_maxttl;
20380731	217
6648bd7e AD	218	/* From ip_input.c */
	219	extern int sysctl_ip_early_demux;
	220
20380731 ACM	221	/* From ip_output.c */
	222	extern int sysctl_ip_dynaddr;
	223
	224	extern void ipfrag_init(void);
	225
bd7b1533 AV	226	extern void ip_static_sysctl_init(void);
bd7b1533 AV	227
d18cd551 DM	228	static inline bool ip_is_fragment(const struct iphdr *iph)
	229	{
	230	return (iph->frag_off & htons(IP_MF \| IP_OFFSET)) != 0;
	231	}
	232
1da177e4	233	#ifdef CONFIG_INET
14c85021 ACM	234	#include <net/dst.h>
14c85021 ACM	235
1da177e4 LT	236	/* The function in 2.2 was invalid, producing wrong result for
	237	* check=0xFEFF. It was noticed by Arthur Skawina _year_ ago. --ANK(000625) */
	238	static inline
	239	int ip_decrease_ttl(struct iphdr *iph)
	240	{
5c78f275 AV	241	u32 check = (__force u32)iph->check;
	242	check += (__force u32)htons(0x0100);
	243	iph->check = (__force __sum16)(check + (check>=0xFFFF));
1da177e4 LT	244	return --iph->ttl;
	245	}
	246
	247	static inline
	248	int ip_dont_fragment(struct sock sk, struct dst_entry dst)
	249	{
a02cec21	250	return inet_sk(sk)->pmtudisc == IP_PMTUDISC_DO \|\|
1da177e4	251	(inet_sk(sk)->pmtudisc == IP_PMTUDISC_WANT &&
a02cec21	252	!(dst_metric_locked(dst, RTAX_MTU)));
1da177e4 LT	253	}
	254
	255	extern void __ip_select_ident(struct iphdr iph, struct dst_entry dst, int more);
	256
	257	static inline void ip_select_ident(struct iphdr iph, struct dst_entry dst, struct sock *sk)
	258	{
	259	if (iph->frag_off & htons(IP_DF)) {
	260	/* This is only to work around buggy Windows95/2000
	261	* VJ compression implementations. If the ID field
	262	* does not change, they drop every other packet in
	263	* a TCP stream using header compression.
	264	*/
c720c7e8 ED	265	iph->id = (sk && inet_sk(sk)->inet_daddr) ?
c720c7e8 ED	266	htons(inet_sk(sk)->inet_id++) : 0;
1da177e4 LT	267	} else
	268	__ip_select_ident(iph, dst, 0);
	269	}
	270
	271	static inline void ip_select_ident_more(struct iphdr iph, struct dst_entry dst, struct sock *sk, int more)
	272	{
	273	if (iph->frag_off & htons(IP_DF)) {
c720c7e8 ED	274	if (sk && inet_sk(sk)->inet_daddr) {
	275	iph->id = htons(inet_sk(sk)->inet_id);
	276	inet_sk(sk)->inet_id += 1 + more;
1da177e4 LT	277	} else
	278	iph->id = 0;
	279	} else
	280	__ip_select_ident(iph, dst, more);
	281	}
	282
	283	/*
	284	* Map a multicast IP onto multicast MAC for type ethernet.
	285	*/
	286
714e85be	287	static inline void ip_eth_mc_map(__be32 naddr, char *buf)
1da177e4	288	{
714e85be	289	__u32 addr=ntohl(naddr);
1da177e4 LT	290	buf[0]=0x01;
	291	buf[1]=0x00;
	292	buf[2]=0x5e;
	293	buf[5]=addr&0xFF;
	294	addr>>=8;
	295	buf[4]=addr&0xFF;
	296	addr>>=8;
	297	buf[3]=addr&0x7F;
	298	}
	299
	300	/*
	301	* Map a multicast IP onto multicast MAC for type IP-over-InfiniBand.
	302	* Leave P_Key as 0 to be filled in by driver.
	303	*/
	304
a9e527e3	305	static inline void ip_ib_mc_map(__be32 naddr, const unsigned char broadcast, char buf)
1da177e4	306	{
714e85be	307	__u32 addr;
a9e527e3 RM	308	unsigned char scope = broadcast[5] & 0xF;
a9e527e3 RM	309
1da177e4 LT	310	buf[0] = 0; /* Reserved */
	311	buf[1] = 0xff; /* Multicast QPN */
	312	buf[2] = 0xff;
	313	buf[3] = 0xff;
714e85be	314	addr = ntohl(naddr);
1da177e4	315	buf[4] = 0xff;
a9e527e3	316	buf[5] = 0x10 \| scope; /* scope from broadcast address */
1da177e4 LT	317	buf[6] = 0x40; /* IPv4 signature */
1da177e4 LT	318	buf[7] = 0x1b;
a9e527e3 RM	319	buf[8] = broadcast[8]; /* P_Key */
a9e527e3 RM	320	buf[9] = broadcast[9];
1da177e4 LT	321	buf[10] = 0;
	322	buf[11] = 0;
	323	buf[12] = 0;
	324	buf[13] = 0;
	325	buf[14] = 0;
	326	buf[15] = 0;
	327	buf[19] = addr & 0xff;
	328	addr >>= 8;
	329	buf[18] = addr & 0xff;
	330	addr >>= 8;
	331	buf[17] = addr & 0xff;
	332	addr >>= 8;
	333	buf[16] = addr & 0x0f;
	334	}
	335
93ca3bb5 TT	336	static inline void ip_ipgre_mc_map(__be32 naddr, const unsigned char broadcast, char buf)
	337	{
	338	if ((broadcast[0] \| broadcast[1] \| broadcast[2] \| broadcast[3]) != 0)
	339	memcpy(buf, broadcast, 4);
	340	else
	341	memcpy(buf, &naddr, sizeof(naddr));
	342	}
	343
dfd56b8b	344	#if IS_ENABLED(CONFIG_IPV6)
1da177e4 LT	345	#include <linux/ipv6.h>
	346	#endif
	347
	348	static __inline__ void inet_reset_saddr(struct sock *sk)
	349	{
c720c7e8	350	inet_sk(sk)->inet_rcv_saddr = inet_sk(sk)->inet_saddr = 0;
dfd56b8b	351	#if IS_ENABLED(CONFIG_IPV6)
1da177e4 LT	352	if (sk->sk_family == PF_INET6) {
	353	struct ipv6_pinfo *np = inet6_sk(sk);
	354
	355	memset(&np->saddr, 0, sizeof(np->saddr));
	356	memset(&np->rcv_saddr, 0, sizeof(np->rcv_saddr));
	357	}
	358	#endif
	359	}
	360
	361	#endif
	362
7ad6848c OP	363	static inline int sk_mc_loop(struct sock *sk)
	364	{
	365	if (!sk)
	366	return 1;
	367	switch (sk->sk_family) {
	368	case AF_INET:
	369	return inet_sk(sk)->mc_loop;
dfd56b8b	370	#if IS_ENABLED(CONFIG_IPV6)
7ad6848c OP	371	case AF_INET6:
	372	return inet6_sk(sk)->mc_loop;
	373	#endif
	374	}
cd65c3c7	375	WARN_ON(1);
7ad6848c OP	376	return 1;
	377	}
	378
ba57b4db	379	extern bool ip_call_ra_chain(struct sk_buff *skb);
1da177e4 LT	380
1da177e4 LT	381	/*
b798232f	382	* Functions provided by ip_fragment.c
1da177e4 LT	383	*/
1da177e4 LT	384
fd2c3ef7	385	enum ip_defrag_users {
1da177e4 LT	386	IP_DEFRAG_LOCAL_DELIVER,
	387	IP_DEFRAG_CALL_RA_CHAIN,
	388	IP_DEFRAG_CONNTRACK_IN,
4be929be	389	__IP_DEFRAG_CONNTRACK_IN_END = IP_DEFRAG_CONNTRACK_IN + USHRT_MAX,
1da177e4	390	IP_DEFRAG_CONNTRACK_OUT,
4be929be	391	__IP_DEFRAG_CONNTRACK_OUT_END = IP_DEFRAG_CONNTRACK_OUT + USHRT_MAX,
8fa9ff68	392	IP_DEFRAG_CONNTRACK_BRIDGE_IN,
4be929be	393	__IP_DEFRAG_CONNTRACK_BRIDGE_IN = IP_DEFRAG_CONNTRACK_BRIDGE_IN + USHRT_MAX,
1da177e4 LT	394	IP_DEFRAG_VS_IN,
1da177e4 LT	395	IP_DEFRAG_VS_OUT,
595fc71b DM	396	IP_DEFRAG_VS_FWD,
595fc71b DM	397	IP_DEFRAG_AF_PACKET,
bc416d97	398	IP_DEFRAG_MACVLAN,
1da177e4 LT	399	};
1da177e4 LT	400
776c729e	401	int ip_defrag(struct sk_buff *skb, u32 user);
bc416d97 ED	402	#ifdef CONFIG_INET
	403	struct sk_buff ip_check_defrag(struct sk_buff skb, u32 user);
	404	#else
	405	static inline struct sk_buff ip_check_defrag(struct sk_buff skb, u32 user)
	406	{
	407	return skb;
	408	}
	409	#endif
6ddc0822	410	int ip_frag_mem(struct net *net);
e5a2bb84	411	int ip_frag_nqueues(struct net *net);
1da177e4 LT	412
	413	/*
	414	* Functions provided by ip_forward.c
	415	*/
	416
	417	extern int ip_forward(struct sk_buff *skb);
1da177e4 LT	418
	419	/*
	420	* Functions provided by ip_options.c
	421	*/
	422
f6d8bd05 ED	423	extern void ip_options_build(struct sk_buff skb, struct ip_options opt,
f6d8bd05 ED	424	__be32 daddr, struct rtable *rt, int is_frag);
1da177e4 LT	425	extern int ip_options_echo(struct ip_options dopt, struct sk_buff skb);
1da177e4 LT	426	extern void ip_options_fragment(struct sk_buff *skb);
0e6bd4a1 DL	427	extern int ip_options_compile(struct net *net,
0e6bd4a1 DL	428	struct ip_options opt, struct sk_buff skb);
f6d8bd05	429	extern int ip_options_get(struct net net, struct ip_options_rcu *optp,
4c6ea29d	430	unsigned char *data, int optlen);
f6d8bd05	431	extern int ip_options_get_from_user(struct net net, struct ip_options_rcu *optp,
4c6ea29d	432	unsigned char __user *data, int optlen);
1da177e4 LT	433	extern void ip_options_undo(struct ip_options * opt);
	434	extern void ip_forward_options(struct sk_buff *skb);
	435	extern int ip_options_rcv_srr(struct sk_buff *skb);
	436
	437	/*
	438	* Functions provided by ip_sockglue.c
	439	*/
	440
d826eb14	441	extern void ipv4_pktinfo_prepare(struct sk_buff *skb);
1da177e4	442	extern void ip_cmsg_recv(struct msghdr msg, struct sk_buff skb);
7a6adb92 DL	443	extern int ip_cmsg_send(struct net *net,
7a6adb92 DL	444	struct msghdr msg, struct ipcm_cookie ipc);
b7058842	445	extern int ip_setsockopt(struct sock sk, int level, int optname, char __user optval, unsigned int optlen);
1da177e4	446	extern int ip_getsockopt(struct sock sk, int level, int optname, char __user optval, int __user *optlen);
3fdadf7d	447	extern int compat_ip_setsockopt(struct sock *sk, int level,
b7058842	448	int optname, char __user *optval, unsigned int optlen);
3fdadf7d DM	449	extern int compat_ip_getsockopt(struct sock *sk, int level,
3fdadf7d DM	450	int optname, char __user optval, int __user optlen);
1da177e4 LT	451	extern int ip_ra_control(struct sock sk, unsigned char on, void (destructor)(struct sock *));
	452
	453	extern int ip_recv_error(struct sock sk, struct msghdr msg, int len);
	454	extern void ip_icmp_error(struct sock sk, struct sk_buff skb, int err,
35986b32	455	__be16 port, u32 info, u8 *payload);
0579016e	456	extern void ip_local_error(struct sock *sk, int err, __be32 daddr, __be16 dport,
1da177e4 LT	457	u32 info);
1da177e4 LT	458
20380731 ACM	459	#ifdef CONFIG_PROC_FS
	460	extern int ip_misc_proc_init(void);
	461	#endif
	462
1da177e4	463	#endif /* _IP_H */