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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.
*
* INET protocol dispatch tables.
*
* Version: @(#)protocol.c 1.0.5 05/25/93
*
* Authors: Ross Biro, <bir7@leland.Stanford.Edu>
* Fred N. van Kempen, <waltje@uWalt.NL.Mugnet.ORG>
*
* Fixes:
* Alan Cox : Ahah! udp icmp errors don't work because
* udp_err is never called!
* Alan Cox : Added new fields for init and ready for
* proper fragmentation (_NO_ 4K limits!)
* Richard Colella : Hang on hash collision
*
* 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.
*/
#include <asm/segment.h>
#include <asm/system.h>
#include <linux/types.h>
#include <linux/kernel.h>
#include <linux/sched.h>
#include <linux/string.h>
#include <linux/config.h>
#include <linux/socket.h>
#include <linux/in.h>
#include <linux/inet.h>
#include <linux/netdevice.h>
#include <linux/timer.h>
#include <net/ip.h>
#include <net/protocol.h>
#include <net/tcp.h>
#include <linux/skbuff.h>
#include <net/sock.h>
#include <net/icmp.h>
#include <net/udp.h>
#include <net/ipip.h>
#include <linux/igmp.h>
#ifdef CONFIG_NET_IPIP
static struct inet_protocol ipip_protocol =
{
ipip_rcv, /* IPIP handler */
NULL, /* TUNNEL error control */
0, /* next */
IPPROTO_IPIP, /* protocol ID */
0, /* copy */
NULL, /* data */
"IPIP" /* name */
};
#endif
static struct inet_protocol tcp_protocol =
{
tcp_rcv, /* TCP handler */
tcp_err, /* TCP error control */
#if defined(CONFIG_NET_IPIP)
&ipip_protocol,
#else
NULL, /* next */
#endif
IPPROTO_TCP, /* protocol ID */
0, /* copy */
NULL, /* data */
"TCP" /* name */
};
static struct inet_protocol udp_protocol =
{
udp_rcv, /* UDP handler */
udp_err, /* UDP error control */
&tcp_protocol, /* next */
IPPROTO_UDP, /* protocol ID */
0, /* copy */
NULL, /* data */
"UDP" /* name */
};
static struct inet_protocol icmp_protocol =
{
icmp_rcv, /* ICMP handler */
NULL, /* ICMP error control */
&udp_protocol, /* next */
IPPROTO_ICMP, /* protocol ID */
0, /* copy */
NULL, /* data */
"ICMP" /* name */
};
#ifndef CONFIG_IP_MULTICAST
struct inet_protocol *inet_protocol_base = &icmp_protocol;
#else
static struct inet_protocol igmp_protocol =
{
igmp_rcv, /* IGMP handler */
NULL, /* IGMP error control */
&icmp_protocol, /* next */
IPPROTO_IGMP, /* protocol ID */
0, /* copy */
NULL, /* data */
"IGMP" /* name */
};
struct inet_protocol *inet_protocol_base = &igmp_protocol;
#endif
struct inet_protocol *inet_protos[MAX_INET_PROTOS] =
{
NULL
};
/*
* Find a protocol in the protocol tables given its
* IP type.
*/
struct inet_protocol *inet_get_protocol(unsigned char prot)
{
unsigned char hash;
struct inet_protocol *p;
hash = prot & (MAX_INET_PROTOS - 1);
for (p = inet_protos[hash] ; p != NULL; p=p->next)
{
if (p->protocol == prot)
return((struct inet_protocol *) p);
}
return(NULL);
}
/*
* Add a protocol handler to the hash tables
*/
void inet_add_protocol(struct inet_protocol *prot)
{
unsigned char hash;
struct inet_protocol *p2;
hash = prot->protocol & (MAX_INET_PROTOS - 1);
prot ->next = inet_protos[hash];
inet_protos[hash] = prot;
prot->copy = 0;
/*
* Set the copy bit if we need to.
*/
p2 = (struct inet_protocol *) prot->next;
while(p2 != NULL)
{
if (p2->protocol == prot->protocol)
{
prot->copy = 1;
break;
}
p2 = (struct inet_protocol *) p2->next;
}
}
/*
* Remove a protocol from the hash tables.
*/
int inet_del_protocol(struct inet_protocol *prot)
{
struct inet_protocol *p;
struct inet_protocol *lp = NULL;
unsigned char hash;
hash = prot->protocol & (MAX_INET_PROTOS - 1);
if (prot == inet_protos[hash])
{
inet_protos[hash] = (struct inet_protocol *) inet_protos[hash]->next;
return(0);
}
p = (struct inet_protocol *) inet_protos[hash];
while(p != NULL)
{
/*
* We have to worry if the protocol being deleted is
* the last one on the list, then we may need to reset
* someone's copied bit.
*/
if (p->next != NULL && p->next == prot)
{
/*
* if we are the last one with this protocol and
* there is a previous one, reset its copy bit.
*/
if (p->copy == 0 && lp != NULL)
lp->copy = 0;
p->next = prot->next;
return(0);
}
if (p->next != NULL && p->next->protocol == prot->protocol)
lp = p;
p = (struct inet_protocol *) p->next;
}
return(-1);
}
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