if.c

eCos操作系统源码

//==========================================================================
//
//      sys/net/if.c
//
//     
//
//==========================================================================
//####BSDCOPYRIGHTBEGIN####
//
// -------------------------------------------
//
// Portions of this software may have been derived from OpenBSD or other sources,
// and are covered by the appropriate copyright disclaimers included herein.
//
// -------------------------------------------
//
//####BSDCOPYRIGHTEND####
//==========================================================================
//#####DESCRIPTIONBEGIN####
//
// Author(s):    gthomas
// Contributors: gthomas
// Date:         2000-01-10
// Purpose:      
// Description:  
//              
//
//####DESCRIPTIONEND####
//
//==========================================================================


/*	$OpenBSD: if.c,v 1.25 1999/12/08 06:50:17 itojun Exp $	*/
/*	$NetBSD: if.c,v 1.35 1996/05/07 05:26:04 thorpej Exp $	*/

/*
 * Copyright (C) 1995, 1996, 1997, and 1998 WIDE Project.
 * All rights reserved.
 * 
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 * 3. Neither the name of the project nor the names of its contributors
 *    may be used to endorse or promote products derived from this software
 *    without specific prior written permission.
 * 
 * THIS SOFTWARE IS PROVIDED BY THE PROJECT AND CONTRIBUTORS ``AS IS'' AND
 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED.  IN NO EVENT SHALL THE PROJECT OR CONTRIBUTORS BE LIABLE
 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 * SUCH DAMAGE.
 */

/*
 * Copyright (c) 1980, 1986, 1993
 *	The Regents of the University of California.  All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 * 3. All advertising materials mentioning features or use of this software
 *    must display the following acknowledgement:
 *	This product includes software developed by the University of
 *	California, Berkeley and its contributors.
 * 4. Neither the name of the University nor the names of its contributors
 *    may be used to endorse or promote products derived from this software
 *    without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 * SUCH DAMAGE.
 *
 *	@(#)if.c	8.3 (Berkeley) 1/4/94
 */

#ifdef __ECOS
#include <pkgconf/net.h>
#else
#include "bpfilter.h"
#include "bridge.h"
#endif

#include <sys/param.h>
#include <sys/mbuf.h>
#ifndef __ECOS
#include <sys/systm.h>
#include <sys/proc.h>
#endif
#include <sys/socket.h>
#include <sys/socketvar.h>
#include <sys/protosw.h>
#include <sys/kernel.h>
#include <sys/ioctl.h>

#include <net/if.h>
#include <net/if_dl.h>
#include <net/if_types.h>
#include <net/radix.h>

#include <net/route.h>

#ifdef INET
#include <netinet/in.h>
#include <netinet/in_var.h>
#include <netinet/if_ether.h>
#include <netinet/igmp.h>
#ifdef MROUTING
#include <netinet/ip_mroute.h>
#endif
#endif

#ifdef INET6
#ifndef INET
#include <netinet/in.h>
#endif
#endif

#ifdef IPFILTER
#include <netinet/ip_fil_compat.h>
#include <netinet/ip_fil.h>
#include <netinet/ip_nat.h>
#endif

#if NBPFILTER > 0
#include <net/bpf.h>
#endif

#if NBRIDGE > 0
#include <net/if_bridge.h>
#endif

void	if_attachsetup __P((struct ifnet *));
int	if_detach_rtdelete __P((struct radix_node *, void *));

int	ifqmaxlen = IFQ_MAXLEN;
void	if_slowtimo __P((void *arg));

#ifdef INET6
/*
 * XXX: declare here to avoid to include many inet6 related files..
 * should be more generalized?
 */
extern void nd6_setmtu __P((struct ifnet *));
#endif 

/*
 * Network interface utility routines.
 *
 * Routines with ifa_ifwith* names take sockaddr *'s as
 * parameters.
 */
void
ifinit()
{
	register struct ifnet *ifp;

	for (ifp = ifnet.tqh_first; ifp != 0; ifp = ifp->if_list.tqe_next)
		if (ifp->if_snd.ifq_maxlen == 0)
			ifp->if_snd.ifq_maxlen = ifqmaxlen;
	if_slowtimo(NULL);
}

int if_index = 0;
struct ifaddr **ifnet_addrs = NULL;
struct ifnet **ifindex2ifnet = NULL;

/*
 * Attach an interface to the
 * list of "active" interfaces.
 */
void
if_attachsetup(ifp)
	struct ifnet *ifp;
{
	unsigned int socksize, ifasize;
	int namelen, masklen;
	register struct sockaddr_dl *sdl;
	register struct ifaddr *ifa;
	static int if_indexlim = 8;

	ifp->if_index = ++if_index;

	/*
	 * We have some arrays that should be indexed by if_index.
	 * since if_index will grow dynamically, they should grow too.
	 *	struct ifadd **ifnet_addrs
	 *	struct ifnet **ifindex2ifnet
	 */
	if (ifnet_addrs == 0 || ifindex2ifnet == 0 || if_index >= if_indexlim) {
		size_t n;
		caddr_t q;
		
		while (if_index >= if_indexlim)
			if_indexlim <<= 1;

		/* grow ifnet_addrs */
		n = if_indexlim * sizeof(ifa);
		q = (caddr_t)malloc(n, M_IFADDR, M_WAITOK);
		bzero(q, n);
		if (ifnet_addrs) {
			bcopy((caddr_t)ifnet_addrs, q, n/2);
			free((caddr_t)ifnet_addrs, M_IFADDR);
		}
		ifnet_addrs = (struct ifaddr **)q;

		/* grow ifindex2ifnet */
		n = if_indexlim * sizeof(struct ifnet *);
		q = (caddr_t)malloc(n, M_IFADDR, M_WAITOK);
		bzero(q, n);
		if (ifindex2ifnet) {
			bcopy((caddr_t)ifindex2ifnet, q, n/2);
			free((caddr_t)ifindex2ifnet, M_IFADDR);
		}
		ifindex2ifnet = (struct ifnet **)q;
	}

	ifindex2ifnet[if_index] = ifp;

	/*
	 * create a Link Level name for this device
	 */
	namelen = strlen(ifp->if_xname);
#define _offsetof(t, m) ((int)((caddr_t)&((t *)0)->m))
	masklen = _offsetof(struct sockaddr_dl, sdl_data[0]) + namelen;
	socksize = masklen + ifp->if_addrlen;
#define ROUNDUP(a) (1 + (((a) - 1) | (sizeof(long) - 1)))
	if (socksize < sizeof(*sdl))
		socksize = sizeof(*sdl);
	socksize = ROUNDUP(socksize);
	ifasize = sizeof(*ifa) + 2 * socksize;
	ifa = (struct ifaddr *)malloc(ifasize, M_IFADDR, M_WAITOK);
	bzero((caddr_t)ifa, ifasize);
	sdl = (struct sockaddr_dl *)(ifa + 1);
	sdl->sdl_len = socksize;
	sdl->sdl_family = AF_LINK;
	bcopy(ifp->if_xname, sdl->sdl_data, namelen);
	sdl->sdl_nlen = namelen;
	sdl->sdl_index = ifp->if_index;
	sdl->sdl_type = ifp->if_type;
	ifnet_addrs[if_index] = ifa;
	ifa->ifa_ifp = ifp;
	ifa->ifa_rtrequest = link_rtrequest;
	TAILQ_INSERT_HEAD(&ifp->if_addrlist, ifa, ifa_list);
	ifa->ifa_addr = (struct sockaddr *)sdl;
	sdl = (struct sockaddr_dl *)(socksize + (caddr_t)sdl);
	ifa->ifa_netmask = (struct sockaddr *)sdl;
	sdl->sdl_len = masklen;
	while (namelen != 0)
		sdl->sdl_data[--namelen] = 0xff;
}

void
if_attachhead(ifp)
	struct ifnet *ifp;
{
	if (if_index == 0)
		TAILQ_INIT(&ifnet);
	TAILQ_INIT(&ifp->if_addrlist);
	TAILQ_INSERT_HEAD(&ifnet, ifp, if_list);
	if_attachsetup(ifp);
}

void
if_attach(ifp)
	struct ifnet *ifp;
{
// Initialize queue - moved here to support "late" attaches
    if (ifp->if_snd.ifq_maxlen == 0)
        ifp->if_snd.ifq_maxlen = ifqmaxlen;
//
	if (if_index == 0)
		TAILQ_INIT(&ifnet);
	TAILQ_INIT(&ifp->if_addrlist);
	TAILQ_INSERT_TAIL(&ifnet, ifp, if_list);
	if_attachsetup(ifp);
}

/*
 * Delete a route if it has a specific interface for output.
 * This function complies to the rn_walktree callback API.
 */
int
if_detach_rtdelete(rn, vifp)
	struct radix_node *rn;
	void *vifp;
{
	struct ifnet *ifp = vifp;
	struct rtentry *rt = (struct rtentry *)rn;

	if (rt->rt_ifp == ifp)
		rtrequest(RTM_DELETE, rt_key(rt), rt->rt_gateway, rt_mask(rt),
		    0, NULL);

	/*
	 * XXX There should be no need to check for rt_ifa belonging to this
	 * interface, because then rt_ifp is set, right?
	 */

	return (0);
}

/*
 * Detach an interface from everything in the kernel.  Also deallocate
 * private resources.
 * XXX So far only the INET protocol family has been looked over
 * wrt resource usage that needs to be decoupled.
 */
void
if_detach(ifp)
	struct ifnet *ifp;
{
	struct ifaddr *ifa;
	int i, s = splimp();
	struct radix_node_head *rnh;

#if NBRIDGE > 0
	/* Remove the interface from any bridge it is part of.  */
	if (ifp->if_bridge)
		bridge_ifdetach(ifp);
#endif

#if NBPFILTER > 0
	/* If there is a bpf device attached, detach from it.  */
	if (ifp->if_bpf)
		bpfdetach(ifp);
#endif

	/*
	 * Find and remove all routes which is using this interface.
	 * XXX Factor out into a route.c function?
	 */
	for (i = 1; i <= AF_MAX; i++) {
		rnh = rt_tables[i];
		if (rnh)
			(*rnh->rnh_walktree)(rnh, if_detach_rtdelete, ifp);
	}

#ifdef INET
	rti_delete(ifp);
	myip_ifp = NULL;
#ifdef MROUTING
	vif_delete(ifp);
#endif
#endif
	/*
	 * XXX transient ifp refs?  inpcb.ip_moptions.imo_multicast_ifp?
	 * Other network stacks than INET?
	 */

	/* Remove the interface from the list of all interfaces.  */
	TAILQ_REMOVE(&ifnet, ifp, if_list);

#ifdef IPFILTER
	/* XXX More ipf & ipnat cleanup needed.  */
	nat_ifdetach(ifp);
#endif

	/* Deallocate private resources.  */
	for (ifa = TAILQ_FIRST(&ifp->if_addrlist); ifa;
	    ifa = TAILQ_FIRST(&ifp->if_addrlist)) {
		TAILQ_REMOVE(&ifp->if_addrlist, ifa, ifa_list);
#ifdef INET
		if (ifa->ifa_addr->sa_family == AF_INET)
			TAILQ_REMOVE(&in_ifaddr, (struct in_ifaddr *)ifa,
			    ia_list);
#endif
		free(ifa, M_IFADDR);
	}
	splx(s);
}

/*
 * Locate an interface based on a complete address.
 */
/*ARGSUSED*/
struct ifaddr *
ifa_ifwithaddr(addr)
	register struct sockaddr *addr;
{
	register struct ifnet *ifp;
	register struct ifaddr *ifa;

#define	equal(a1, a2) \
  (bcmp((caddr_t)(a1), (caddr_t)(a2), ((struct sockaddr *)(a1))->sa_len) == 0)
	for (ifp = ifnet.tqh_first; ifp != 0; ifp = ifp->if_list.tqe_next)
	    for (ifa = ifp->if_addrlist.tqh_first; ifa != 0; ifa = ifa->ifa_list.tqe_next) {
		if (ifa->ifa_addr->sa_family != addr->sa_family)
			continue;
		if (ifa->ifa_dstaddr == NULL)
			continue;
		if (equal(addr, ifa->ifa_addr))
			return (ifa);
		if ((ifp->if_flags & IFF_BROADCAST) && ifa->ifa_broadaddr &&
		    /* IP6 doesn't have broadcast */
		    ifa->ifa_broadaddr->sa_len != 0 &&
		    equal(ifa->ifa_broadaddr, addr))
			return (ifa);
	}
	return (NULL);
}
/*
 * Locate the point to point interface with a given destination address.
 */
/*ARGSUSED*/
struct ifaddr *
ifa_ifwithdstaddr(addr)
	register struct sockaddr *addr;
{
	register struct ifnet *ifp;
	register struct ifaddr *ifa;

	for (ifp = ifnet.tqh_first; ifp != 0; ifp = ifp->if_list.tqe_next)
	    if (ifp->if_flags & IFF_POINTOPOINT)
		for (ifa = ifp->if_addrlist.tqh_first; ifa != 0; ifa = ifa->ifa_list.tqe_next) {
			if (ifa->ifa_addr->sa_family != addr->sa_family ||
			    ifa->ifa_dstaddr == NULL)
				continue;
			if (equal(addr, ifa->ifa_dstaddr))
				return (ifa);
	}
	return (NULL);
}

/*
 * Find an interface on a specific network.  If many, choice
 * is most specific found.
 */
struct ifaddr *
ifa_ifwithnet(addr)
	struct sockaddr *addr;
{
	register struct ifnet *ifp;
	register struct ifaddr *ifa;
	struct ifaddr *ifa_maybe = 0;
	u_int af = addr->sa_family;
	char *addr_data = addr->sa_data, *cplim;

	if (af == AF_LINK) {
	    register struct sockaddr_dl *sdl = (struct sockaddr_dl *)addr;
	    if (sdl->sdl_index && sdl->sdl_index <= if_index)
		return (ifnet_addrs[sdl->sdl_index]);
	}
	for (ifp = ifnet.tqh_first; ifp != 0; ifp = ifp->if_list.tqe_next)
		for (ifa = ifp->if_addrlist.tqh_first; ifa != 0; ifa = ifa->ifa_list.tqe_next) {
			register char *cp, *cp2, *cp3;

			if (ifa->ifa_addr->sa_family != af ||
			    ifa->ifa_netmask == 0)
				next: continue;
			cp = addr_data;
			cp2 = ifa->ifa_addr->sa_data;
			cp3 = ifa->ifa_netmask->sa_data;
			cplim = (char *)ifa->ifa_netmask +
				ifa->ifa_netmask->sa_len;
			while (cp3 < cplim)
				if ((*cp++ ^ *cp2++) & *cp3++)
				    /* want to continue for() loop */
					goto next;