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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!)
*
* 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 "ip.h"
#include "protocol.h"
#include "tcp.h"
#include <linux/skbuff.h>
#include "sock.h"
#include "icmp.h"
#include "udp.h"
#include <linux/igmp.h>
static struct inet_protocol tcp_protocol = {
tcp_rcv, /* TCP handler */
NULL, /* No fragment handler (and won't be for a long time) */
tcp_err, /* TCP error control */
NULL, /* next */
IPPROTO_TCP, /* protocol ID */
0, /* copy */
NULL, /* data */
"TCP" /* name */
};
static struct inet_protocol udp_protocol = {
udp_rcv, /* UDP handler */
NULL, /* Will be UDP fraglist 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 never fragments anyway */
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 never fragments anyway */
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
};
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);
}
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 *) prot->next;
}
}
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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