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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, <bir7@leland.Stanford.Edu>
* Fred N. van Kempen, <waltje@uWalt.NL.Mugnet.ORG>
* Alan Cox, <gw4pts@gw4pts.ampr.org>
*
* 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/ip.h>
#include <linux/config.h>
#ifndef _SNMP_H
#include "snmp.h"
#endif
#include "sock.h" /* struct sock */
/* 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 */
#ifdef CONFIG_IP_MULTICAST
extern void ip_mc_dropsocket(struct sock *);
extern void ip_mc_dropdevice(struct device *dev);
extern int ip_mc_procinfo(char *, char **, off_t, int);
#define MULTICAST(x) (IN_MULTICAST(htonl(x)))
#endif
/* Describe an IP fragment. */
struct ipfrag {
int offset; /* offset of fragment in IP datagram */
int end; /* last byte of data in datagram */
int len; /* length of this fragment */
struct sk_buff *skb; /* complete received fragment */
unsigned char *ptr; /* pointer into real fragment data */
struct ipfrag *next; /* linked list pointers */
struct ipfrag *prev;
};
/* Describe an entry in the "incomplete datagrams" queue. */
struct ipq {
unsigned char *mac; /* pointer to MAC header */
struct iphdr *iph; /* pointer to IP header */
int len; /* total length of original datagram */
short ihlen; /* length of the IP header */
short maclen; /* length of the MAC header */
struct timer_list timer; /* when will this queue expire? */
struct ipfrag *fragments; /* linked list of received fragments */
struct ipq *next; /* linked list pointers */
struct ipq *prev;
struct device *dev; /* Device - for icmp replies */
};
extern int backoff(int n);
extern void ip_print(const struct iphdr *ip);
extern int ip_ioctl(struct sock *sk, int cmd,
unsigned long arg);
extern void ip_route_check(unsigned long daddr);
extern int ip_build_header(struct sk_buff *skb,
unsigned long saddr,
unsigned long daddr,
struct device **dev, int type,
struct options *opt, int len,
int tos,int ttl);
extern unsigned short ip_compute_csum(unsigned char * buff, int len);
extern int ip_rcv(struct sk_buff *skb, struct device *dev,
struct packet_type *pt);
extern void ip_send_check(struct iphdr *ip);
extern int ip_id_count;
extern void ip_queue_xmit(struct sock *sk,
struct device *dev, struct sk_buff *skb,
int free);
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 void ip_init(void);
extern struct ip_mib ip_statistics;
/*
* This is a version of ip_compute_csum() optimized for IP headers, which
* always checksum on 4 octet boundaries.
* Used by ip.c and slhc.c (the net driver module)
* (Moved to here by bj0rn@blox.se)
*/
static inline unsigned short ip_fast_csum(unsigned char * buff, int wlen)
{
unsigned long sum = 0;
if (wlen)
{
unsigned long bogus;
__asm__("clc\n"
"1:\t"
"lodsl\n\t"
"adcl %3, %0\n\t"
"decl %2\n\t"
"jne 1b\n\t"
"adcl $0, %0\n\t"
"movl %0, %3\n\t"
"shrl $16, %3\n\t"
"addw %w3, %w0\n\t"
"adcw $0, %w0"
: "=r" (sum), "=S" (buff), "=r" (wlen), "=a" (bogus)
: "0" (sum), "1" (buff), "2" (wlen));
}
return (~sum) & 0xffff;
}
#endif /* _IP_H */
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