/* * 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, <bir7@leland.Stanford.Edu> *		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/config.h>#include <linux/types.h>#include <linux/socket.h>#include <linux/ip.h>#include <linux/netdevice.h>#include <linux/inetdevice.h>#include <linux/in_route.h>#include <net/route.h>#include <net/arp.h>#ifndef _SNMP_H#include <net/snmp.h>#endif#include <net/sock.h>	/* struct sock */struct inet_skb_parm{	struct ip_options	opt;		/* Compiled IP options		*/	unsigned char		flags;#define IPSKB_MASQUERADED	1#define IPSKB_TRANSLATED	2#define IPSKB_FORWARDED		4};struct ipcm_cookie{	u32			addr;	int			oif;	struct ip_options	*opt;};#define IPCB(skb) ((struct inet_skb_parm*)((skb)->cb))struct ip_ra_chain{	struct ip_ra_chain	*next;	struct sock		*sk;	void			(*destructor)(struct sock *);};extern struct ip_ra_chain *ip_ra_chain;extern rwlock_t ip_ra_lock;/* 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	*/extern void		ip_mc_dropsocket(struct sock *);extern void		ip_mc_dropdevice(struct net_device *dev);extern int		ip_mc_procinfo(char *, char **, off_t, int);/* *	Functions provided by ip.c */extern int		ip_build_and_send_pkt(struct sk_buff *skb, struct sock *sk,					      u32 saddr, u32 daddr,					      struct ip_options *opt);extern int		ip_rcv(struct sk_buff *skb, struct net_device *dev,			       struct packet_type *pt);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 (*out)(struct sk_buff*));extern int		ip_do_nat(struct sk_buff *skb);extern void		ip_send_check(struct iphdr *ip);extern int		ip_queue_xmit(struct sk_buff *skb);extern void		ip_init(void);extern int		ip_build_xmit(struct sock *sk,				      int getfrag (const void *,						   char *,						   unsigned int,						   unsigned int),				      const void *frag,				      unsigned length,				      struct ipcm_cookie *ipc,				      struct rtable *rt,				      int flags);/* *	Map a multicast IP onto multicast MAC for type Token Ring. *      This conforms to RFC1469 Option 2 Multicasting i.e. *      using a functional address to transmit / receive  *      multicast packets. */static inline void ip_tr_mc_map(u32 addr, char *buf){	buf[0]=0xC0;	buf[1]=0x00;	buf[2]=0x00;	buf[3]=0x04;	buf[4]=0x00;	buf[5]=0x00;}struct ip_reply_arg {	struct iovec iov[2];   	int          n_iov;    /* redundant */	u32 	     csum; 	int	     csumoffset; /* u16 offset of csum in iov[0].iov_base */				 /* -1 if not needed */ }; void ip_send_reply(struct sock *sk, struct sk_buff *skb, struct ip_reply_arg *arg,		   unsigned int len); extern __inline__ int ip_finish_output(struct sk_buff *skb);struct ipv4_config{	int	log_martians;	int	autoconfig;	int	no_pmtu_disc;};extern struct ipv4_config ipv4_config;extern struct ip_mib	ip_statistics[NR_CPUS*2];#define IP_INC_STATS(field)		SNMP_INC_STATS(ip_statistics, field)#define IP_INC_STATS_BH(field)		SNMP_INC_STATS_BH(ip_statistics, field)#define IP_INC_STATS_USER(field) 	SNMP_INC_STATS_USER(ip_statistics, field)extern struct linux_mib	net_statistics[NR_CPUS*2];#define NET_INC_STATS(field)		SNMP_INC_STATS(net_statistics, field)#define NET_INC_STATS_BH(field)		SNMP_INC_STATS_BH(net_statistics, field)#define NET_INC_STATS_USER(field) 	SNMP_INC_STATS_USER(net_statistics, field)extern int sysctl_local_port_range[2];extern int sysctl_ip_default_ttl;#ifdef CONFIG_INETstatic inline int ip_send(struct sk_buff *skb){	if (skb->len > skb->dst->pmtu)		return ip_fragment(skb, ip_finish_output);	else		return ip_finish_output(skb);}/* The function in 2.2 was invalid, producing wrong result for * check=0xFEFF. It was noticed by Arthur Skawina _year_ ago. --ANK(000625) */static inlineint ip_decrease_ttl(struct iphdr *iph){	u32 check = iph->check;	check += __constant_htons(0x0100);	iph->check = check + (check>=0xFFFF);	return --iph->ttl;}static inlineint ip_dont_fragment(struct sock *sk, struct dst_entry *dst){	return (sk->protinfo.af_inet.pmtudisc == IP_PMTUDISC_DO ||		(sk->protinfo.af_inet.pmtudisc == IP_PMTUDISC_WANT &&		 !(dst->mxlock&(1<<RTAX_MTU))));}extern void __ip_select_ident(struct iphdr *iph, struct dst_entry *dst);static inline void ip_select_ident(struct iphdr *iph, struct dst_entry *dst, struct sock *sk){	if (iph->frag_off&__constant_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 && sk->daddr) ? htons(sk->protinfo.af_inet.id++) : 0);	} else		__ip_select_ident(iph, dst);}/* *	Map a multicast IP onto multicast MAC for type ethernet. */static inline void ip_eth_mc_map(u32 addr, char *buf){	addr=ntohl(addr);	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;}#endifextern int	ip_call_ra_chain(struct sk_buff *skb);/* *	Functions provided by ip_fragment.o */ struct sk_buff *ip_defrag(struct sk_buff *skb);extern int ip_frag_nqueues;extern atomic_t ip_frag_mem;/* *	Functions provided by ip_forward.c */ extern int ip_forward(struct sk_buff *skb);extern int ip_net_unreachable(struct sk_buff *skb); /* *	Functions provided by ip_options.c */ extern void ip_options_build(struct sk_buff *skb, struct ip_options *opt, u32 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 ip_options *opt, struct sk_buff *skb);extern int ip_options_get(struct ip_options **optp, unsigned char *data, int optlen, int user);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	ip_cmsg_recv(struct msghdr *msg, struct sk_buff *skb);extern int	ip_cmsg_send(struct msghdr *msg, struct ipcm_cookie *ipc);extern int	ip_setsockopt(struct sock *sk, int level, int optname, char *optval, int optlen);extern int	ip_getsockopt(struct sock *sk, int level, int optname, char *optval, int *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, 			      u16 port, u32 info, u8 *payload);extern void	ip_local_error(struct sock *sk, int err, u32 daddr, u16 dport,			       u32 info);#endif	/* _IP_H */