[mirror_ubuntu-artful-kernel.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, <waltje@uWalt.NL.Mugnet.ORG>
 *		Alan Cox, <gw4pts@gw4pts.ampr.org>
 *
 * 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/route.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;
	__u8			ttl;
	__s16			tos;
	char			priority;
};

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

int igmp_mc_init(void);

/*
 *	Functions provided by ip.c
 */

int ip_build_and_send_pkt(struct sk_buff *skb, struct sock *sk,
			  __be32 saddr, __be32 daddr,
			  struct ip_options_rcu *opt);
int ip_rcv(struct sk_buff *skb, struct net_device *dev, struct packet_type *pt,
	   struct net_device *orig_dev);
int ip_local_deliver(struct sk_buff *skb);
int ip_mr_input(struct sk_buff *skb);
int ip_output(struct sock *sk, struct sk_buff *skb);
int ip_mc_output(struct sock *sk, struct sk_buff *skb);
int ip_fragment(struct sk_buff *skb, int (*output)(struct sk_buff *));
int ip_do_nat(struct sk_buff *skb);
void ip_send_check(struct iphdr *ip);
int __ip_local_out(struct sk_buff *skb);
int ip_local_out_sk(struct sock *sk, struct sk_buff *skb);
static inline int ip_local_out(struct sk_buff *skb)
{
	return ip_local_out_sk(skb->sk, skb);
}

int ip_queue_xmit(struct sock *sk, struct sk_buff *skb, struct flowi *fl);
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);
ssize_t ip_append_page(struct sock *sk, struct flowi4 *fl4, struct page *page,
		       int offset, size_t size, int flags);
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,
			    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);
}

static inline __u8 get_rttos(struct ipcm_cookie* ipc, struct inet_sock *inet)
{
	return (ipc->tos != -1) ? RT_TOS(ipc->tos) : RT_TOS(inet->tos);
}

static inline __u8 get_rtconn_flags(struct ipcm_cookie* ipc, struct sock* sk)
{
	return (ipc->tos != -1) ? RT_CONN_FLAGS_TOS(sk, ipc->tos) : RT_CONN_FLAGS(sk);
}

/* datagram.c */
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 {
	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);

#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(net, field, adnd)	SNMP_ADD_STATS((net)->mib.net_statistics, field, adnd)
#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)

unsigned long snmp_fold_field(void __percpu *mib, int offt);
#if BITS_PER_LONG==32
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

void inet_get_local_port_range(struct net *net, 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;

void ipfrag_init(void);

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)));
}

static inline bool ip_sk_accept_pmtu(const struct sock *sk)
{
	return inet_sk(sk)->pmtudisc != IP_PMTUDISC_INTERFACE &&
	       inet_sk(sk)->pmtudisc != IP_PMTUDISC_OMIT;
}

static inline bool ip_sk_use_pmtu(const struct sock *sk)
{
	return inet_sk(sk)->pmtudisc < IP_PMTUDISC_PROBE;
}

static inline bool ip_sk_local_df(const struct sock *sk)
{
	return inet_sk(sk)->pmtudisc < IP_PMTUDISC_DO ||
	       inet_sk(sk)->pmtudisc == IP_PMTUDISC_OMIT;
}

static inline unsigned int ip_dst_mtu_maybe_forward(const struct dst_entry *dst,
						    bool forwarding)
{
	struct net *net = dev_net(dst->dev);

	if (net->ipv4.sysctl_ip_fwd_use_pmtu ||
	    dst_metric_locked(dst, RTAX_MTU) ||
	    !forwarding)
		return dst_mtu(dst);

	return min(dst->dev->mtu, IP_MAX_MTU);
}

static inline unsigned int ip_skb_dst_mtu(const struct sk_buff *skb)
{
	if (!skb->sk || ip_sk_use_pmtu(skb->sk)) {
		bool forwarding = IPCB(skb)->flags & IPSKB_FORWARDED;
		return ip_dst_mtu_maybe_forward(skb_dst(skb), forwarding);
	} else {
		return min(skb_dst(skb)->dev->mtu, IP_MAX_MTU);
	}
}

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

static inline void ip_select_ident(struct sk_buff *skb, struct dst_entry *dst, struct sock *sk)
{
	struct iphdr *iph = ip_hdr(skb);

	if ((iph->frag_off & htons(IP_DF)) && !skb->local_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 sk_buff *skb, struct dst_entry *dst, struct sock *sk, int more)
{
	struct iphdr *iph = ip_hdr(skb);

	if ((iph->frag_off & htons(IP_DF)) && !skb->local_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);
}

static inline __wsum inet_compute_pseudo(struct sk_buff *skb, int proto)
{
	return csum_tcpudp_nofold(ip_hdr(skb)->saddr, ip_hdr(skb)->daddr,
				  skb->len, proto, 0);
}

/*
 *	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(&sk->sk_v6_rcv_saddr, 0, sizeof(sk->sk_v6_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;
}

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
 */
 
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 is_frag);
int ip_options_echo(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);
int ip_options_get(struct net *net, struct ip_options_rcu **optp,
		   unsigned char *data, int optlen);
int ip_options_get_from_user(struct net *net, struct ip_options_rcu **optp,
			     unsigned char __user *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);

/*
 *	Functions provided by ip_sockglue.c
 */

void ipv4_pktinfo_prepare(const struct sock *sk, struct sk_buff *skb);
void ip_cmsg_recv(struct msghdr *msg, struct sk_buff *skb);
int ip_cmsg_send(struct net *net, struct msghdr *msg,
		 struct ipcm_cookie *ipc, bool allow_ipv6);
int ip_setsockopt(struct sock *sk, int level, int optname, char __user *optval,
		  unsigned int optlen);
int ip_getsockopt(struct sock *sk, int level, int optname, char __user *optval,
		  int __user *optlen);
int compat_ip_setsockopt(struct sock *sk, int level, int optname,
			 char __user *optval, unsigned int optlen);
int compat_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);

#ifdef CONFIG_PROC_FS
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, <waltje@uWalt.NL.Mugnet.ORG>
	12	* Alan Cox, <gw4pts@gw4pts.ampr.org>
	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>
aa661581	31	#include <net/route.h>
1da177e4	32	#include <net/snmp.h>
86b08d86	33	#include <net/flow.h>
1da177e4 LT	34
	35	struct sock;
	36
fd2c3ef7	37	struct inet_skb_parm {
1da177e4 LT	38	struct ip_options opt; /* Compiled IP options */
	39	unsigned char flags;
	40
8cdfab8a PM	41	#define IPSKB_FORWARDED 1
8cdfab8a PM	42	#define IPSKB_XFRM_TUNNEL_SIZE 2
3e3850e9 PM	43	#define IPSKB_XFRM_TRANSFORMED 4
3e3850e9 PM	44	#define IPSKB_FRAG_COMPLETE 8
48d5cad8	45	#define IPSKB_REROUTED 16
5f2d04f1 PM	46
5f2d04f1 PM	47	u16 frag_max_size;
1da177e4 LT	48	};
1da177e4 LT	49
c9bdd4b5 ACM	50	static inline unsigned int ip_hdrlen(const struct sk_buff *skb)
c9bdd4b5 ACM	51	{
eddc9ec5	52	return ip_hdr(skb)->ihl * 4;
c9bdd4b5 ACM	53	}
c9bdd4b5 ACM	54
fd2c3ef7	55	struct ipcm_cookie {
c1d18f9f	56	__be32 addr;
1da177e4	57	int oif;
f6d8bd05	58	struct ip_options_rcu *opt;
2244d07b	59	__u8 tx_flags;
f02db315 FF	60	__u8 ttl;
	61	__s16 tos;
	62	char priority;
1da177e4 LT	63	};
	64
	65	#define IPCB(skb) ((struct inet_skb_parm*)((skb)->cb))
4b261c75	66	#define PKTINFO_SKB_CB(skb) ((struct in_pktinfo *)((skb)->cb))
1da177e4	67
fd2c3ef7	68	struct ip_ra_chain {
43a951e9	69	struct ip_ra_chain __rcu *next;
1da177e4	70	struct sock *sk;
592fcb9d ED	71	union {
	72	void (destructor)(struct sock );
	73	struct sock *saved_sk;
	74	};
66018506	75	struct rcu_head rcu;
1da177e4 LT	76	};
1da177e4 LT	77
43a951e9	78	extern struct ip_ra_chain __rcu *ip_ra_chain;
1da177e4 LT	79
	80	/* IP flags. */
	81	#define IP_CE 0x8000 /* Flag: "Congestion" */
	82	#define IP_DF 0x4000 /* Flag: "Don't Fragment" */
	83	#define IP_MF 0x2000 /* Flag: "More Fragments" */
	84	#define IP_OFFSET 0x1FFF /* "Fragment Offset" part */
	85
	86	#define IP_FRAG_TIME (30 * HZ) /* fragment lifetime */
	87
14c85021 ACM	88	struct msghdr;
	89	struct net_device;
	90	struct packet_type;
	91	struct rtable;
14c85021 ACM	92	struct sockaddr;
14c85021 ACM	93
72c1d3bd	94	int igmp_mc_init(void);
1da177e4 LT	95
	96	/*
	97	* Functions provided by ip.c
	98	*/
	99
5c3a0fd7 JP	100	int ip_build_and_send_pkt(struct sk_buff skb, struct sock sk,
	101	__be32 saddr, __be32 daddr,
	102	struct ip_options_rcu *opt);
	103	int ip_rcv(struct sk_buff skb, struct net_device dev, struct packet_type *pt,
	104	struct net_device *orig_dev);
	105	int ip_local_deliver(struct sk_buff *skb);
	106	int ip_mr_input(struct sk_buff *skb);
aad88724 ED	107	int ip_output(struct sock sk, struct sk_buff skb);
aad88724 ED	108	int ip_mc_output(struct sock sk, struct sk_buff skb);
5c3a0fd7 JP	109	int ip_fragment(struct sk_buff skb, int (output)(struct sk_buff *));
	110	int ip_do_nat(struct sk_buff *skb);
	111	void ip_send_check(struct iphdr *ip);
	112	int __ip_local_out(struct sk_buff *skb);
aad88724 ED	113	int ip_local_out_sk(struct sock sk, struct sk_buff skb);
	114	static inline int ip_local_out(struct sk_buff *skb)
	115	{
	116	return ip_local_out_sk(skb->sk, skb);
	117	}
	118
b0270e91	119	int ip_queue_xmit(struct sock sk, struct sk_buff skb, struct flowi *fl);
5c3a0fd7 JP	120	void ip_init(void);
	121	int ip_append_data(struct sock sk, struct flowi4 fl4,
	122	int getfrag(void from, char to, int offset, int len,
	123	int odd, struct sk_buff *skb),
	124	void *from, int len, int protolen,
	125	struct ipcm_cookie *ipc,
	126	struct rtable **rt,
	127	unsigned int flags);
	128	int ip_generic_getfrag(void from, char to, int offset, int len, int odd,
	129	struct sk_buff *skb);
	130	ssize_t ip_append_page(struct sock sk, struct flowi4 fl4, struct page *page,
	131	int offset, size_t size, int flags);
	132	struct sk_buff __ip_make_skb(struct sock sk, struct flowi4 *fl4,
	133	struct sk_buff_head *queue,
	134	struct inet_cork *cork);
	135	int ip_send_skb(struct net net, struct sk_buff skb);
	136	int ip_push_pending_frames(struct sock sk, struct flowi4 fl4);
	137	void ip_flush_pending_frames(struct sock *sk);
	138	struct sk_buff ip_make_skb(struct sock sk, struct flowi4 *fl4,
	139	int getfrag(void from, char to, int offset,
	140	int len, int odd, struct sk_buff *skb),
	141	void *from, int length, int transhdrlen,
	142	struct ipcm_cookie ipc, struct rtable *rtp,
	143	unsigned int flags);
1c32c5ad	144
77968b78	145	static inline struct sk_buff ip_finish_skb(struct sock sk, struct flowi4 *fl4)
1c32c5ad	146	{
77968b78	147	return __ip_make_skb(sk, fl4, &sk->sk_write_queue, &inet_sk(sk)->cork.base);
1c32c5ad	148	}
1da177e4	149
aa661581 FF	150	static inline __u8 get_rttos(struct ipcm_cookie* ipc, struct inet_sock *inet)
	151	{
	152	return (ipc->tos != -1) ? RT_TOS(ipc->tos) : RT_TOS(inet->tos);
	153	}
	154
	155	static inline __u8 get_rtconn_flags(struct ipcm_cookie* ipc, struct sock* sk)
	156	{
	157	return (ipc->tos != -1) ? RT_CONN_FLAGS_TOS(sk, ipc->tos) : RT_CONN_FLAGS(sk);
	158	}
	159
1da177e4	160	/* datagram.c */
5c3a0fd7	161	int ip4_datagram_connect(struct sock sk, struct sockaddr uaddr, int addr_len);
1da177e4	162
5c3a0fd7	163	void ip4_datagram_release_cb(struct sock *sk);
8141ed9f	164
1da177e4 LT	165	struct ip_reply_arg {
1da177e4 LT	166	struct kvec iov[1];
88ef4a5a	167	int flags;
d6f5493c	168	__wsum csum;
1da177e4 LT	169	int csumoffset; /* u16 offset of csum in iov[0].iov_base */
1da177e4 LT	170	/* -1 if not needed */
f0e48dbf	171	int bound_dev_if;
66b13d99	172	u8 tos;
1da177e4 LT	173	};
1da177e4 LT	174
88ef4a5a KK	175	#define IP_REPLY_ARG_NOSRCCHECK 1
88ef4a5a KK	176
86b08d86 KK	177	static inline __u8 ip_reply_arg_flowi_flags(const struct ip_reply_arg *arg)
	178	{
	179	return (arg->flags & IP_REPLY_ARG_NOSRCCHECK) ? FLOWI_FLAG_ANYSRC : 0;
	180	}
	181
be9f4a44	182	void ip_send_unicast_reply(struct net net, struct sk_buff skb, __be32 daddr,
70e73416 DM	183	__be32 saddr, const struct ip_reply_arg *arg,
70e73416 DM	184	unsigned int len);
1da177e4	185
4ce3c183 ED	186	#define IP_INC_STATS(net, field) SNMP_INC_STATS64((net)->mib.ip_statistics, field)
	187	#define IP_INC_STATS_BH(net, field) SNMP_INC_STATS64_BH((net)->mib.ip_statistics, field)
	188	#define IP_ADD_STATS(net, field, val) SNMP_ADD_STATS64((net)->mib.ip_statistics, field, val)
	189	#define IP_ADD_STATS_BH(net, field, val) SNMP_ADD_STATS64_BH((net)->mib.ip_statistics, field, val)
	190	#define IP_UPD_PO_STATS(net, field, val) SNMP_UPD_PO_STATS64((net)->mib.ip_statistics, field, val)
	191	#define IP_UPD_PO_STATS_BH(net, field, val) SNMP_UPD_PO_STATS64_BH((net)->mib.ip_statistics, field, val)
61a7e260 PE	192	#define NET_INC_STATS(net, field) SNMP_INC_STATS((net)->mib.net_statistics, field)
	193	#define NET_INC_STATS_BH(net, field) SNMP_INC_STATS_BH((net)->mib.net_statistics, field)
	194	#define NET_INC_STATS_USER(net, field) SNMP_INC_STATS_USER((net)->mib.net_statistics, field)
f7324acd	195	#define NET_ADD_STATS(net, field, adnd) SNMP_ADD_STATS((net)->mib.net_statistics, field, adnd)
61a7e260 PE	196	#define NET_ADD_STATS_BH(net, field, adnd) SNMP_ADD_STATS_BH((net)->mib.net_statistics, field, adnd)
61a7e260 PE	197	#define NET_ADD_STATS_USER(net, field, adnd) SNMP_ADD_STATS_USER((net)->mib.net_statistics, field, adnd)
1da177e4	198
698365fa	199	unsigned long snmp_fold_field(void __percpu *mib, int offt);
4ce3c183	200	#if BITS_PER_LONG==32
698365fa	201	u64 snmp_fold_field64(void __percpu *mib, int offt, size_t sync_off);
4ce3c183	202	#else
698365fa	203	static inline u64 snmp_fold_field64(void __percpu *mib, int offt, size_t syncp_off)
4ce3c183 ED	204	{
	205	return snmp_fold_field(mib, offt);
	206	}
	207	#endif
33490170	208
0bbf87d8	209	void inet_get_local_port_range(struct net net, int low, int *high);
227b60f5	210
e3826f1e AW	211	extern unsigned long *sysctl_local_reserved_ports;
	212	static inline int inet_is_reserved_local_port(int port)
	213	{
	214	return test_bit(port, sysctl_local_reserved_ports);
	215	}
	216
cdac4e07	217	extern int sysctl_ip_nonlocal_bind;
1da177e4	218
20380731 ACM	219	/* From inetpeer.c */
	220	extern int inet_peer_threshold;
	221	extern int inet_peer_minttl;
	222	extern int inet_peer_maxttl;
20380731	223
6648bd7e AD	224	/* From ip_input.c */
	225	extern int sysctl_ip_early_demux;
	226
20380731 ACM	227	/* From ip_output.c */
	228	extern int sysctl_ip_dynaddr;
	229
5c3a0fd7	230	void ipfrag_init(void);
20380731	231
5c3a0fd7	232	void ip_static_sysctl_init(void);
bd7b1533	233
d18cd551 DM	234	static inline bool ip_is_fragment(const struct iphdr *iph)
	235	{
	236	return (iph->frag_off & htons(IP_MF \| IP_OFFSET)) != 0;
	237	}
	238
1da177e4	239	#ifdef CONFIG_INET
14c85021 ACM	240	#include <net/dst.h>
14c85021 ACM	241
1da177e4 LT	242	/* The function in 2.2 was invalid, producing wrong result for
	243	* check=0xFEFF. It was noticed by Arthur Skawina _year_ ago. --ANK(000625) */
	244	static inline
	245	int ip_decrease_ttl(struct iphdr *iph)
	246	{
5c78f275 AV	247	u32 check = (__force u32)iph->check;
	248	check += (__force u32)htons(0x0100);
	249	iph->check = (__force __sum16)(check + (check>=0xFFFF));
1da177e4 LT	250	return --iph->ttl;
	251	}
	252
	253	static inline
	254	int ip_dont_fragment(struct sock sk, struct dst_entry dst)
	255	{
a02cec21	256	return inet_sk(sk)->pmtudisc == IP_PMTUDISC_DO \|\|
1da177e4	257	(inet_sk(sk)->pmtudisc == IP_PMTUDISC_WANT &&
a02cec21	258	!(dst_metric_locked(dst, RTAX_MTU)));
1da177e4 LT	259	}
1da177e4 LT	260
f87c10a8 HFS	261	static inline bool ip_sk_accept_pmtu(const struct sock *sk)
f87c10a8 HFS	262	{
1b346576 HFS	263	return inet_sk(sk)->pmtudisc != IP_PMTUDISC_INTERFACE &&
1b346576 HFS	264	inet_sk(sk)->pmtudisc != IP_PMTUDISC_OMIT;
f87c10a8 HFS	265	}
	266
	267	static inline bool ip_sk_use_pmtu(const struct sock *sk)
	268	{
	269	return inet_sk(sk)->pmtudisc < IP_PMTUDISC_PROBE;
	270	}
	271
1b346576 HFS	272	static inline bool ip_sk_local_df(const struct sock *sk)
	273	{
	274	return inet_sk(sk)->pmtudisc < IP_PMTUDISC_DO \|\|
	275	inet_sk(sk)->pmtudisc == IP_PMTUDISC_OMIT;
	276	}
	277
f87c10a8 HFS	278	static inline unsigned int ip_dst_mtu_maybe_forward(const struct dst_entry *dst,
	279	bool forwarding)
	280	{
	281	struct net *net = dev_net(dst->dev);
	282
	283	if (net->ipv4.sysctl_ip_fwd_use_pmtu \|\|
	284	dst_metric_locked(dst, RTAX_MTU) \|\|
	285	!forwarding)
	286	return dst_mtu(dst);
	287
	288	return min(dst->dev->mtu, IP_MAX_MTU);
	289	}
	290
	291	static inline unsigned int ip_skb_dst_mtu(const struct sk_buff *skb)
	292	{
	293	if (!skb->sk \|\| ip_sk_use_pmtu(skb->sk)) {
	294	bool forwarding = IPCB(skb)->flags & IPSKB_FORWARDED;
	295	return ip_dst_mtu_maybe_forward(skb_dst(skb), forwarding);
	296	} else {
	297	return min(skb_dst(skb)->dev->mtu, IP_MAX_MTU);
	298	}
	299	}
	300
5c3a0fd7	301	void __ip_select_ident(struct iphdr iph, struct dst_entry dst, int more);
1da177e4	302
703133de	303	static inline void ip_select_ident(struct sk_buff skb, struct dst_entry dst, struct sock *sk)
1da177e4	304	{
703133de AA	305	struct iphdr *iph = ip_hdr(skb);
	306
	307	if ((iph->frag_off & htons(IP_DF)) && !skb->local_df) {
1da177e4 LT	308	/* This is only to work around buggy Windows95/2000
	309	* VJ compression implementations. If the ID field
	310	* does not change, they drop every other packet in
	311	* a TCP stream using header compression.
	312	*/
c720c7e8 ED	313	iph->id = (sk && inet_sk(sk)->inet_daddr) ?
c720c7e8 ED	314	htons(inet_sk(sk)->inet_id++) : 0;
1da177e4 LT	315	} else
	316	__ip_select_ident(iph, dst, 0);
	317	}
	318
703133de	319	static inline void ip_select_ident_more(struct sk_buff skb, struct dst_entry dst, struct sock *sk, int more)
1da177e4	320	{
703133de AA	321	struct iphdr *iph = ip_hdr(skb);
	322
	323	if ((iph->frag_off & htons(IP_DF)) && !skb->local_df) {
c720c7e8 ED	324	if (sk && inet_sk(sk)->inet_daddr) {
	325	iph->id = htons(inet_sk(sk)->inet_id);
	326	inet_sk(sk)->inet_id += 1 + more;
1da177e4 LT	327	} else
	328	iph->id = 0;
	329	} else
	330	__ip_select_ident(iph, dst, more);
	331	}
	332
ed70fcfc TH	333	static inline __wsum inet_compute_pseudo(struct sk_buff *skb, int proto)
	334	{
	335	return csum_tcpudp_nofold(ip_hdr(skb)->saddr, ip_hdr(skb)->daddr,
	336	skb->len, proto, 0);
	337	}
	338
1da177e4 LT	339	/*
	340	* Map a multicast IP onto multicast MAC for type ethernet.
	341	*/
	342
714e85be	343	static inline void ip_eth_mc_map(__be32 naddr, char *buf)
1da177e4	344	{
714e85be	345	__u32 addr=ntohl(naddr);
1da177e4 LT	346	buf[0]=0x01;
	347	buf[1]=0x00;
	348	buf[2]=0x5e;
	349	buf[5]=addr&0xFF;
	350	addr>>=8;
	351	buf[4]=addr&0xFF;
	352	addr>>=8;
	353	buf[3]=addr&0x7F;
	354	}
	355
	356	/*
	357	* Map a multicast IP onto multicast MAC for type IP-over-InfiniBand.
	358	* Leave P_Key as 0 to be filled in by driver.
	359	*/
	360
a9e527e3	361	static inline void ip_ib_mc_map(__be32 naddr, const unsigned char broadcast, char buf)
1da177e4	362	{
714e85be	363	__u32 addr;
a9e527e3 RM	364	unsigned char scope = broadcast[5] & 0xF;
a9e527e3 RM	365
1da177e4 LT	366	buf[0] = 0; /* Reserved */
	367	buf[1] = 0xff; /* Multicast QPN */
	368	buf[2] = 0xff;
	369	buf[3] = 0xff;
714e85be	370	addr = ntohl(naddr);
1da177e4	371	buf[4] = 0xff;
a9e527e3	372	buf[5] = 0x10 \| scope; /* scope from broadcast address */
1da177e4 LT	373	buf[6] = 0x40; /* IPv4 signature */
1da177e4 LT	374	buf[7] = 0x1b;
a9e527e3 RM	375	buf[8] = broadcast[8]; /* P_Key */
a9e527e3 RM	376	buf[9] = broadcast[9];
1da177e4 LT	377	buf[10] = 0;
	378	buf[11] = 0;
	379	buf[12] = 0;
	380	buf[13] = 0;
	381	buf[14] = 0;
	382	buf[15] = 0;
	383	buf[19] = addr & 0xff;
	384	addr >>= 8;
	385	buf[18] = addr & 0xff;
	386	addr >>= 8;
	387	buf[17] = addr & 0xff;
	388	addr >>= 8;
	389	buf[16] = addr & 0x0f;
	390	}
	391
93ca3bb5 TT	392	static inline void ip_ipgre_mc_map(__be32 naddr, const unsigned char broadcast, char buf)
	393	{
	394	if ((broadcast[0] \| broadcast[1] \| broadcast[2] \| broadcast[3]) != 0)
	395	memcpy(buf, broadcast, 4);
	396	else
	397	memcpy(buf, &naddr, sizeof(naddr));
	398	}
	399
dfd56b8b	400	#if IS_ENABLED(CONFIG_IPV6)
1da177e4 LT	401	#include <linux/ipv6.h>
	402	#endif
	403
	404	static __inline__ void inet_reset_saddr(struct sock *sk)
	405	{
c720c7e8	406	inet_sk(sk)->inet_rcv_saddr = inet_sk(sk)->inet_saddr = 0;
dfd56b8b	407	#if IS_ENABLED(CONFIG_IPV6)
1da177e4 LT	408	if (sk->sk_family == PF_INET6) {
	409	struct ipv6_pinfo *np = inet6_sk(sk);
	410
	411	memset(&np->saddr, 0, sizeof(np->saddr));
efe4208f	412	memset(&sk->sk_v6_rcv_saddr, 0, sizeof(sk->sk_v6_rcv_saddr));
1da177e4 LT	413	}
	414	#endif
	415	}
	416
	417	#endif
	418
7ad6848c OP	419	static inline int sk_mc_loop(struct sock *sk)
	420	{
	421	if (!sk)
	422	return 1;
	423	switch (sk->sk_family) {
	424	case AF_INET:
	425	return inet_sk(sk)->mc_loop;
dfd56b8b	426	#if IS_ENABLED(CONFIG_IPV6)
7ad6848c OP	427	case AF_INET6:
	428	return inet6_sk(sk)->mc_loop;
	429	#endif
	430	}
cd65c3c7	431	WARN_ON(1);
7ad6848c OP	432	return 1;
	433	}
	434
5c3a0fd7	435	bool ip_call_ra_chain(struct sk_buff *skb);
1da177e4 LT	436
1da177e4 LT	437	/*
b798232f	438	* Functions provided by ip_fragment.c
1da177e4 LT	439	*/
1da177e4 LT	440
fd2c3ef7	441	enum ip_defrag_users {
1da177e4 LT	442	IP_DEFRAG_LOCAL_DELIVER,
	443	IP_DEFRAG_CALL_RA_CHAIN,
	444	IP_DEFRAG_CONNTRACK_IN,
4be929be	445	__IP_DEFRAG_CONNTRACK_IN_END = IP_DEFRAG_CONNTRACK_IN + USHRT_MAX,
1da177e4	446	IP_DEFRAG_CONNTRACK_OUT,
4be929be	447	__IP_DEFRAG_CONNTRACK_OUT_END = IP_DEFRAG_CONNTRACK_OUT + USHRT_MAX,
8fa9ff68	448	IP_DEFRAG_CONNTRACK_BRIDGE_IN,
4be929be	449	__IP_DEFRAG_CONNTRACK_BRIDGE_IN = IP_DEFRAG_CONNTRACK_BRIDGE_IN + USHRT_MAX,
1da177e4 LT	450	IP_DEFRAG_VS_IN,
1da177e4 LT	451	IP_DEFRAG_VS_OUT,
595fc71b DM	452	IP_DEFRAG_VS_FWD,
595fc71b DM	453	IP_DEFRAG_AF_PACKET,
bc416d97	454	IP_DEFRAG_MACVLAN,
1da177e4 LT	455	};
1da177e4 LT	456
776c729e	457	int ip_defrag(struct sk_buff *skb, u32 user);
bc416d97 ED	458	#ifdef CONFIG_INET
	459	struct sk_buff ip_check_defrag(struct sk_buff skb, u32 user);
	460	#else
	461	static inline struct sk_buff ip_check_defrag(struct sk_buff skb, u32 user)
	462	{
	463	return skb;
	464	}
	465	#endif
6ddc0822	466	int ip_frag_mem(struct net *net);
e5a2bb84	467	int ip_frag_nqueues(struct net *net);
1da177e4 LT	468
	469	/*
	470	* Functions provided by ip_forward.c
	471	*/
	472
5c3a0fd7	473	int ip_forward(struct sk_buff *skb);
1da177e4 LT	474
	475	/*
	476	* Functions provided by ip_options.c
	477	*/
	478
5c3a0fd7 JP	479	void ip_options_build(struct sk_buff skb, struct ip_options opt,
	480	__be32 daddr, struct rtable *rt, int is_frag);
	481	int ip_options_echo(struct ip_options dopt, struct sk_buff skb);
	482	void ip_options_fragment(struct sk_buff *skb);
	483	int ip_options_compile(struct net net, struct ip_options opt,
	484	struct sk_buff *skb);
	485	int ip_options_get(struct net net, struct ip_options_rcu *optp,
	486	unsigned char *data, int optlen);
	487	int ip_options_get_from_user(struct net net, struct ip_options_rcu *optp,
	488	unsigned char __user *data, int optlen);
	489	void ip_options_undo(struct ip_options *opt);
	490	void ip_forward_options(struct sk_buff *skb);
	491	int ip_options_rcv_srr(struct sk_buff *skb);
1da177e4 LT	492
	493	/*
	494	* Functions provided by ip_sockglue.c
	495	*/
	496
fbf8866d	497	void ipv4_pktinfo_prepare(const struct sock sk, struct sk_buff skb);
5c3a0fd7	498	void ip_cmsg_recv(struct msghdr msg, struct sk_buff skb);
c8e6ad08 HFS	499	int ip_cmsg_send(struct net net, struct msghdr msg,
c8e6ad08 HFS	500	struct ipcm_cookie *ipc, bool allow_ipv6);
5c3a0fd7 JP	501	int ip_setsockopt(struct sock sk, int level, int optname, char __user optval,
	502	unsigned int optlen);
	503	int ip_getsockopt(struct sock sk, int level, int optname, char __user optval,
	504	int __user *optlen);
	505	int compat_ip_setsockopt(struct sock *sk, int level, int optname,
	506	char __user *optval, unsigned int optlen);
	507	int compat_ip_getsockopt(struct sock *sk, int level, int optname,
	508	char __user optval, int __user optlen);
	509	int ip_ra_control(struct sock *sk, unsigned char on,
	510	void (destructor)(struct sock ));
	511
85fbaa75	512	int ip_recv_error(struct sock sk, struct msghdr msg, int len, int *addr_len);
5c3a0fd7 JP	513	void ip_icmp_error(struct sock sk, struct sk_buff skb, int err, __be16 port,
	514	u32 info, u8 *payload);
	515	void ip_local_error(struct sock *sk, int err, __be32 daddr, __be16 dport,
	516	u32 info);
1da177e4	517
20380731	518	#ifdef CONFIG_PROC_FS
5c3a0fd7	519	int ip_misc_proc_init(void);
20380731 ACM	520	#endif
20380731 ACM	521
1da177e4	522	#endif /* _IP_H */