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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: $Id: protocol.c,v 1.14 2001/05/18 02:25:49 davem Exp $
*
* 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
* Vince Laviano : Modified inet_del_protocol() to correctly
* maintain copy bit.
*
* 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/uaccess.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 <linux/brlock.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>
#define IPPROTO_PREVIOUS NULL
#ifdef CONFIG_IP_MULTICAST
static struct inet_protocol igmp_protocol = {
handler: igmp_rcv,
next: IPPROTO_PREVIOUS,
protocol: IPPROTO_IGMP,
name: "IGMP"
};
#undef IPPROTO_PREVIOUS
#define IPPROTO_PREVIOUS &igmp_protocol
#endif
static struct inet_protocol tcp_protocol = {
handler: tcp_v4_rcv,
err_handler: tcp_v4_err,
next: IPPROTO_PREVIOUS,
protocol: IPPROTO_TCP,
name: "TCP"
};
#undef IPPROTO_PREVIOUS
#define IPPROTO_PREVIOUS &tcp_protocol
static struct inet_protocol udp_protocol = {
handler: udp_rcv,
err_handler: udp_err,
next: IPPROTO_PREVIOUS,
protocol: IPPROTO_UDP,
name: "UDP"
};
#undef IPPROTO_PREVIOUS
#define IPPROTO_PREVIOUS &udp_protocol
static struct inet_protocol icmp_protocol = {
handler: icmp_rcv,
next: IPPROTO_PREVIOUS,
protocol: IPPROTO_ICMP,
name: "ICMP"
};
#undef IPPROTO_PREVIOUS
#define IPPROTO_PREVIOUS &icmp_protocol
struct inet_protocol *inet_protocol_base = IPPROTO_PREVIOUS;
struct inet_protocol *inet_protos[MAX_INET_PROTOS];
/*
* 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);
br_write_lock_bh(BR_NETPROTO_LOCK);
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) {
if (p2->protocol == prot->protocol) {
prot->copy = 1;
break;
}
p2 = (struct inet_protocol *) p2->next;
}
br_write_unlock_bh(BR_NETPROTO_LOCK);
}
/*
* 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);
br_write_lock_bh(BR_NETPROTO_LOCK);
if (prot == inet_protos[hash]) {
inet_protos[hash] = (struct inet_protocol *) inet_protos[hash]->next;
br_write_unlock_bh(BR_NETPROTO_LOCK);
return 0;
}
p = (struct inet_protocol *) inet_protos[hash];
if (p != NULL && p->protocol == prot->protocol)
lp = p;
while (p) {
/*
* 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 && p->next == prot) {
/*
* if we are the last one with this protocol and
* there is a previous one, reset its copy bit.
*/
if (prot->copy == 0 && lp != NULL)
lp->copy = 0;
p->next = prot->next;
br_write_unlock_bh(BR_NETPROTO_LOCK);
return 0;
}
if (p->next != NULL && p->next->protocol == prot->protocol)
lp = p->next;
p = (struct inet_protocol *) p->next;
}
br_write_unlock_bh(BR_NETPROTO_LOCK);
return -1;
}
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