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/*
* 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/snmp.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
};
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 *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 */
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 *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, int ipfragok);
extern void ip_init(void);
extern int ip_append_data(struct sock *sk,
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 page *page,
int offset, size_t size, int flags);
extern int ip_push_pending_frames(struct sock *sk);
extern void ip_flush_pending_frames(struct sock *sk);
/* datagram.c */
extern int ip4_datagram_connect(struct sock *sk,
struct sockaddr *uaddr, int addr_len);
/*
* 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(__be32 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 kvec iov[1];
__wsum csum;
int csumoffset; /* u16 offset of csum in iov[0].iov_base */
/* -1 if not needed */
int bound_dev_if;
};
void ip_send_reply(struct sock *sk, struct sk_buff *skb, struct ip_reply_arg *arg,
unsigned int len);
struct ipv4_config
{
int log_martians;
int no_pmtu_disc;
};
extern struct ipv4_config ipv4_config;
DECLARE_SNMP_STAT(struct ipstats_mib, ip_statistics);
#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)
#define IP_ADD_STATS_BH(field, val) SNMP_ADD_STATS_BH(ip_statistics, field, val)
DECLARE_SNMP_STAT(struct linux_mib, net_statistics);
#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)
#define NET_ADD_STATS_BH(field, adnd) SNMP_ADD_STATS_BH(net_statistics, field, adnd)
#define NET_ADD_STATS_USER(field, adnd) SNMP_ADD_STATS_USER(net_statistics, field, adnd)
extern unsigned long snmp_fold_field(void *mib[], int offt);
extern int snmp_mib_init(void *ptr[2], size_t mibsize);
extern void snmp_mib_free(void *ptr[2]);
extern void inet_get_local_port_range(int *low, int *high);
extern int sysctl_ip_default_ttl;
extern int sysctl_ip_nonlocal_bind;
/* From ip_fragment.c */
struct inet_frags_ctl;
extern struct inet_frags_ctl ip4_frags_ctl;
extern int sysctl_ipfrag_max_dist;
/* From inetpeer.c */
extern int inet_peer_threshold;
extern int inet_peer_minttl;
extern int inet_peer_maxttl;
extern int inet_peer_gc_mintime;
extern int inet_peer_gc_maxtime;
/* From ip_output.c */
extern int sysctl_ip_dynaddr;
extern void ipfrag_init(void);
#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(dst, RTAX_LOCK)&(1<<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)->daddr) ?
htons(inet_sk(sk)->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)->daddr) {
iph->id = htons(inet_sk(sk)->id);
inet_sk(sk)->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,
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