in.c

eCos操作系统源码

//==========================================================================
//
//      sys/netinet/in.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: in.c,v 1.14 1999/12/08 06:50:19 itojun Exp $	*/
/*	$NetBSD: in.c,v 1.26 1996/02/13 23:41:39 christos Exp $	*/

/*
 * Copyright (c) 1982, 1986, 1991, 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.
 *
 *	@(#)in.c	8.2 (Berkeley) 11/15/93
 */

#ifdef __ECOS
#include <pkgconf/net.h>
#else
#include "ether.h"
#include "gif.h"
#endif

#include <sys/param.h>
#include <sys/ioctl.h>
#include <sys/errno.h>
#include <sys/malloc.h>
#include <sys/socket.h>
#include <sys/socketvar.h>
#ifndef __ECOS
#include <sys/systm.h>
#endif

#include <net/if.h>
#include <net/if_types.h>
#include <net/route.h>
#if NGIF > 0
#include <net/if_gif.h>
#endif

#include <netinet/in_systm.h>
#include <netinet/in.h>
#include <netinet/in_var.h>
#include <netinet/if_ether.h>
#include <netinet/igmp_var.h>

#ifdef MROUTING
#include <netinet/ip_mroute.h>
#endif

#ifdef INET

static int in_mask2len __P((struct in_addr *));
static void in_len2mask __P((struct in_addr *, int));
static int in_lifaddr_ioctl __P((struct socket *, u_long, caddr_t,
	struct ifnet *));

#ifndef SUBNETSARELOCAL
#define	SUBNETSARELOCAL	0
#endif
int subnetsarelocal = SUBNETSARELOCAL;
/*
 * Return 1 if an internet address is for a ``local'' host
 * (one to which we have a connection).  If subnetsarelocal
 * is true, this includes other subnets of the local net.
 * Otherwise, it includes only the directly-connected (sub)nets.
 */
int
in_localaddr(in)
	struct in_addr in;
{
	register struct in_ifaddr *ia;

	if (subnetsarelocal) {
		for (ia = in_ifaddr.tqh_first; ia != 0; ia = ia->ia_list.tqe_next)
			if ((in.s_addr & ia->ia_netmask) == ia->ia_net)
				return (1);
	} else {
		for (ia = in_ifaddr.tqh_first; ia != 0; ia = ia->ia_list.tqe_next)
			if ((in.s_addr & ia->ia_subnetmask) == ia->ia_subnet)
				return (1);
	}
	return (0);
}

/*
 * Determine whether an IP address is in a reserved set of addresses
 * that may not be forwarded, or whether datagrams to that destination
 * may be forwarded.
 */
int
in_canforward(in)
	struct in_addr in;
{
	register u_int32_t net;

	if (IN_EXPERIMENTAL(in.s_addr) || IN_MULTICAST(in.s_addr))
		return (0);
	if (IN_CLASSA(in.s_addr)) {
		net = in.s_addr & IN_CLASSA_NET;
		if (net == 0 || net == htonl(IN_LOOPBACKNET << IN_CLASSA_NSHIFT))
			return (0);
	}
	return (1);
}

/*
 * Trim a mask in a sockaddr
 */
void
in_socktrim(ap)
	struct sockaddr_in *ap;
{
	register char *cplim = (char *) &ap->sin_addr;
	register char *cp = (char *) (&ap->sin_addr + 1);

	ap->sin_len = 0;
	while (--cp >= cplim)
		if (*cp) {
			(ap)->sin_len = cp - (char *) (ap) + 1;
			break;
		}
}

static int
in_mask2len(mask)
	struct in_addr *mask;
{
	int x, y;
	u_char *p;

	p = (u_char *)mask;
	for (x = 0; x < sizeof(*mask); x++) {
		if (p[x] != 0xff)
			break;
	}
	y = 0;
	if (x < sizeof(*mask)) {
		for (y = 0; y < 8; y++) {
			if ((p[x] & (0x80 >> y)) == 0)
				break;
		}
	}
	return x * 8 + y;
}

static void
in_len2mask(mask, len)
	struct in_addr *mask;
	int len;
{
	int i;
	u_char *p;

	p = (u_char *)mask;
	bzero(mask, sizeof(*mask));
	for (i = 0; i < len / 8; i++)
		p[i] = 0xff;
	if (len % 8)
		p[i] = (0xff00 >> (len % 8)) & 0xff;
}

int	in_interfaces;		/* number of external internet interfaces */

/*
 * Generic internet control operations (ioctl's).
 * Ifp is 0 if not an interface-specific ioctl.
 */
/* ARGSUSED */
int
in_control(so, cmd, data, ifp)
	struct socket *so;
	u_long cmd;
	caddr_t data;
	register struct ifnet *ifp;
{
	register struct ifreq *ifr = (struct ifreq *)data;
	register struct in_ifaddr *ia = 0;
	struct in_aliasreq *ifra = (struct in_aliasreq *)data;
	struct sockaddr_in oldaddr;
	int error, hostIsNew, maskIsNew;

#if NGIF > 0
	if (ifp && ifp->if_type == IFT_GIF) {
		switch (cmd) {
		case SIOCSIFPHYADDR:
			if ((so->so_state & SS_PRIV) == 0)
				return(EPERM);
		case SIOCGIFPSRCADDR:
		case SIOCGIFPDSTADDR:
			return gif_ioctl(ifp, cmd, data);
		}
	}
#endif

	switch (cmd) {
	case SIOCALIFADDR:
	case SIOCDLIFADDR:
		if ((so->so_state & SS_PRIV) == 0)
			return(EPERM);
		/*fall through*/
	case SIOCGLIFADDR:
		if (!ifp)
			return EINVAL;
		return in_lifaddr_ioctl(so, cmd, data, ifp);
	}

	/*
	 * Find address for this interface, if it exists.
	 */
	if (ifp)
		for (ia = in_ifaddr.tqh_first; ia; ia = ia->ia_list.tqe_next)
			if (ia->ia_ifp == ifp)
				break;

	switch (cmd) {

	case SIOCAIFADDR:
	case SIOCDIFADDR:

	case SIOCSIFADDR: // Moved from after this search, otherwise repeated
	    // identical SIOCSIFADDRs leaked the previously allocated record.

		if (ifra->ifra_addr.sin_family == AF_INET)
		    for (; ia != 0; ia = ia->ia_list.tqe_next) {
			if (ia->ia_ifp == ifp  &&
			    ia->ia_addr.sin_addr.s_addr ==
				ifra->ifra_addr.sin_addr.s_addr)
			    break;
		}
		if (cmd == SIOCDIFADDR && ia == 0)
			return (EADDRNOTAVAIL);
		/* FALLTHROUGH */
	case SIOCSIFNETMASK:
	case SIOCSIFDSTADDR:
		if ((so->so_state & SS_PRIV) == 0)
			return (EPERM);

		if (ifp == 0)
			panic("in_control");
		if (ia == (struct in_ifaddr *)0) {
			ia = (struct in_ifaddr *)
				malloc(sizeof *ia, M_IFADDR, M_WAITOK); // This alloc was leaked
			if (ia == (struct in_ifaddr *)0)
				return (ENOBUFS);
			bzero((caddr_t)ia, sizeof *ia);
			TAILQ_INSERT_TAIL(&in_ifaddr, ia, ia_list);
			TAILQ_INSERT_TAIL(&ifp->if_addrlist, (struct ifaddr *)ia,
			    ifa_list);
			ia->ia_ifa.ifa_addr = sintosa(&ia->ia_addr);
			ia->ia_ifa.ifa_dstaddr = sintosa(&ia->ia_dstaddr);
			ia->ia_ifa.ifa_netmask = sintosa(&ia->ia_sockmask);
			ia->ia_sockmask.sin_len = 8;
			if (ifp->if_flags & IFF_BROADCAST) {
				ia->ia_broadaddr.sin_len = sizeof(ia->ia_addr);
				ia->ia_broadaddr.sin_family = AF_INET;
			}
			ia->ia_ifp = ifp;
			LIST_INIT(&ia->ia_multiaddrs);
			if ((ifp->if_flags & IFF_LOOPBACK) == 0)
				in_interfaces++;
		}
		break;

	case SIOCSIFBRDADDR:
		if ((so->so_state & SS_PRIV) == 0)
			return (EPERM);
		/* FALLTHROUGH */

	case SIOCGIFADDR:
	case SIOCGIFNETMASK:
	case SIOCGIFDSTADDR:
	case SIOCGIFBRDADDR:
		if (ia && satosin(&ifr->ifr_addr)->sin_addr.s_addr) {
			struct in_ifaddr *ia2;

			for (ia2 = ia; ia2; ia2 = ia2->ia_list.tqe_next) {
				if (ia2->ia_ifp == ifp &&
				    ia2->ia_addr.sin_addr.s_addr ==
				    satosin(&ifr->ifr_addr)->sin_addr.s_addr)
					break;
			}
			if (ia2 && ia2->ia_ifp == ifp)
				ia = ia2;
		}
		if (ia == (struct in_ifaddr *)0)
			return (EADDRNOTAVAIL);
		break;
	}
	switch (cmd) {

	case SIOCGIFADDR:
		*satosin(&ifr->ifr_addr) = ia->ia_addr;
		break;

	case SIOCGIFBRDADDR:
		if ((ifp->if_flags & IFF_BROADCAST) == 0)
			return (EINVAL);
		*satosin(&ifr->ifr_dstaddr) = ia->ia_broadaddr;
		break;

	case SIOCGIFDSTADDR:
		if ((ifp->if_flags & IFF_POINTOPOINT) == 0)
			return (EINVAL);
		*satosin(&ifr->ifr_dstaddr) = ia->ia_dstaddr;
		break;

	case SIOCGIFNETMASK:
		*satosin(&ifr->ifr_addr) = ia->ia_sockmask;
		break;

	case SIOCSIFDSTADDR:
		if ((ifp->if_flags & IFF_POINTOPOINT) == 0)
			return (EINVAL);
		oldaddr = ia->ia_dstaddr;
		ia->ia_dstaddr = *satosin(&ifr->ifr_dstaddr);
		if (ifp->if_ioctl && (error = (*ifp->if_ioctl)
					(ifp, SIOCSIFDSTADDR, (caddr_t)ia))) {
			ia->ia_dstaddr = oldaddr;
			return (error);
		}
		if (ia->ia_flags & IFA_ROUTE) {
			ia->ia_ifa.ifa_dstaddr = sintosa(&oldaddr);
			rtinit(&(ia->ia_ifa), (int)RTM_DELETE, RTF_HOST);
			ia->ia_ifa.ifa_dstaddr = sintosa(&ia->ia_dstaddr);
			rtinit(&(ia->ia_ifa), (int)RTM_ADD, RTF_HOST|RTF_UP);
		}
		break;

	case SIOCSIFBRDADDR:
		if ((ifp->if_flags & IFF_BROADCAST) == 0)
			return (EINVAL);
		ia->ia_broadaddr = *satosin(&ifr->ifr_broadaddr);
		break;

	case SIOCSIFADDR:
		return (in_ifinit(ifp, ia, satosin(&ifr->ifr_addr), 1));

	case SIOCSIFNETMASK:
		ia->ia_subnetmask = ia->ia_sockmask.sin_addr.s_addr =
		    ifra->ifra_addr.sin_addr.s_addr;
		break;

	case SIOCAIFADDR:
		maskIsNew = 0;
		hostIsNew = 1;
		error = 0;
		if (ia->ia_addr.sin_family == AF_INET) {
			if (ifra->ifra_addr.sin_len == 0) {
				ifra->ifra_addr = ia->ia_addr;
				hostIsNew = 0;
			} else if (ifra->ifra_addr.sin_addr.s_addr ==
					       ia->ia_addr.sin_addr.s_addr)
				hostIsNew = 0;
		}
		if (ifra->ifra_mask.sin_len) {
			in_ifscrub(ifp, ia);
			ia->ia_sockmask = ifra->ifra_mask;
			ia->ia_subnetmask = ia->ia_sockmask.sin_addr.s_addr;
			maskIsNew = 1;
		}
		if ((ifp->if_flags & IFF_POINTOPOINT) &&
		    (ifra->ifra_dstaddr.sin_family == AF_INET)) {
			in_ifscrub(ifp, ia);
			ia->ia_dstaddr = ifra->ifra_dstaddr;
			maskIsNew  = 1; /* We lie; but the effect's the same */
		}
		if (ifra->ifra_addr.sin_family == AF_INET &&
		    (hostIsNew || maskIsNew))
			error = in_ifinit(ifp, ia, &ifra->ifra_addr, 0);
		if ((ifp->if_flags & IFF_BROADCAST) &&
		    (ifra->ifra_broadaddr.sin_family == AF_INET))
			ia->ia_broadaddr = ifra->ifra_broadaddr;
		return (error);

	case SIOCDIFADDR:
		in_ifscrub(ifp, ia);
		TAILQ_REMOVE(&ifp->if_addrlist, (struct ifaddr *)ia, ifa_list);
		TAILQ_REMOVE(&in_ifaddr, ia, ia_list);
		IFAFREE((&ia->ia_ifa));
		break;

#ifdef MROUTING
	case SIOCGETVIFCNT:
	case SIOCGETSGCNT:
		return (mrt_ioctl(cmd, data));
#endif /* MROUTING */

	default:
		if (ifp == 0 || ifp->if_ioctl == 0)
			return (EOPNOTSUPP);
		return ((*ifp->if_ioctl)(ifp, cmd, data));
	}
	return (0);
}

/*
 * SIOC[GAD]LIFADDR.
 *	SIOCGLIFADDR: get first address. ( ??? )