if_subr.c

VXWORKS源代码

/* if_subr.c - common routines for network interface drivers */

/* Copyright 1990 - 2002 Wind River Systems, Inc. */
#include "copyright_wrs.h"

/*
 * Copyright (c) 1982, 1989, 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_ethersubr.c	8.1 (Berkeley) 6/10/93
 */

/*
modification history
--------------------
01q,23may02,vvv  removed unnecessary m_copy from ether_output (SPR #77775)
01p,22apr02,wap  call ip_mloopback() rather than calling looutput() directly
                 (SPR #72246)
01o,15apr02,wap  reinstate netJobAdd removal changes
01n,29mar02,wap  back out the previous change (needs more investigation)
01m,21mar02,rae  remove unecessary netJobAdd() SPR #
01l,21mar02,vvv  updated man page for copyFromMbufs (SPR #20787)
01k,01nov01,rae  fixed compile warnings, corrected WV event (SPR #71284)
01j,12oct01,rae  merge from truestack ver 01o, base 01h (SPR #69112 etc.)
01i,17oct00,spm  updated ether_attach to report memory allocation failures
01h,21aug98,n_s  updated if_omcast in ether_output () if_noproto in 
                 do_protocol_with_type (). spr21074
01f,19sep97,vin  modified build_cluster to incorporate cluster blks,
		 removed pointers to refcounts.
01g,11aug97,vin  changed mBlkGet to use _pNetDpool.
01e,10jul97,vin  removed unsupported revarpinput() code.
01f,05jun97,vin  corrected processing for promiscuous interfaces in
		 ether_input.
01e,02jun97,spm  updated man page for bcopy_to_mbufs()
01d,15may97,vin  reworked ether_input, cleanup, added copyFromMbufs().
		 removed support for check_trailer().
01c,16dec96,vin  removed unnecessary ntohs(). 
01b,13nov96,vin  replaced m_gethdr with mBlkGet() in buildCluster.
01a,03mar96,vin  created from BSD4.4 stuff,integrated with 02p of if_subr.c
*/

#include "vxWorks.h"
#include "stdlib.h"
#include "stdio.h"
#include "tickLib.h"
#include "logLib.h"
#include "errno.h"
#include "netinet/in.h"
#include "netinet/in_systm.h"
#include "netinet/in_var.h"
#include "netinet/ip.h"
#include "net/if.h"
#include "net/if_arp.h"
#include "netinet/if_ether.h"
#include "net/if_subr.h"
#include "netinet/in_var.h"
#include "netinet/ip_var.h"    /* for ipintr() prototype */
#include "net/mbuf.h"
#include "net/route.h"
#include "net/if_llc.h"
#include "net/if_dl.h"
#include "net/if_types.h"
#include "lstLib.h"
#include "netLib.h"
#include "muxLib.h"
#include "memPartLib.h"

#ifdef WV_INSTRUMENTATION
#ifdef INCLUDE_WVNET
#include "wvNetLib.h"
#endif /* INCLUDE_WVNET */
#endif

#ifdef VIRTUAL_STACK
#include "netinet/vsLib.h"
#endif

typedef struct net_type
    {
    NODE     	node;
    FUNCPTR     inputRtn;
    int     	etherType;
    } NET_TYPE;

#ifdef WV_INSTRUMENTATION
#ifdef INCLUDE_WVNET
    /* Set common fields of event identifiers for this module. */

LOCAL UCHAR wvNetModuleId = WV_NET_IFSUBR_MODULE;   /* Value for if_subr.c */
LOCAL UCHAR wvNetLocalFilter = WV_NET_NONE;     /* Available event filter */

LOCAL ULONG wvNetEventId;       /* Event identifier: see wvNetLib.h */
#endif    /* INCLUDE_WVNET */
#endif

/* externs */

#ifndef VIRTUAL_STACK
extern	struct ifnet loif;
extern  void ip_mloopback(struct ifnet *, struct mbuf *, struct sockaddr_in *,
                          struct rtentry *rt);
#endif /* VIRTUAL_STACK */

u_char	etherbroadcastaddr[6] = { 0xff, 0xff, 0xff, 0xff, 0xff, 0xff };
u_char	ether_ipmulticast_min[6] = { 0x01, 0x00, 0x5e, 0x00, 0x00, 0x00 };
u_char	ether_ipmulticast_max[6] = { 0x01, 0x00, 0x5e, 0x7f, 0xff, 0xff };

#define senderr(e) { error = (e); goto bad;}

LOCAL LIST netTypeList;

/*
 * Ethernet output routine.
 * Encapsulate a packet of type family for the local net.
 * Use trailer local net encapsulation if enough data in first
 * packet leaves a multiple of 512 bytes of data in remainder.
 * Assumes that ifp is actually pointer to arpcom structure.
 */
int
ether_output(ifp, m0, dst, rt0)
	register struct ifnet *ifp;
	struct mbuf *m0;
	struct sockaddr *dst;
	struct rtentry *rt0;
{
	u_short etype;
	int s, error = 0;
 	u_char edst[6];
	register struct mbuf *m = m0;
	register struct rtentry *rt;
	register struct ether_header *eh;
	int off, len = m->m_pkthdr.len;
	struct arpcom *ac = (struct arpcom *)ifp;

	if ((ifp->if_flags & (IFF_UP|IFF_RUNNING)) != (IFF_UP|IFF_RUNNING))
            {
#ifdef WV_INSTRUMENTATION
#ifdef INCLUDE_WVNET    /* WV_NET_CRITICAL event */
            WV_NET_EVENT_1 (NET_CORE_EVENT, WV_NET_CRITICAL, 2, 3,
                            WV_NETEVENT_ETHEROUT_IFDOWN, WV_NET_SEND, ifp)
#endif  /* INCLUDE_WVNET */
#endif

            senderr(ENETDOWN);
            }
	ifp->if_lastchange = tickGet();
	if ((rt = rt0)) {
		if ((rt->rt_flags & RTF_UP) == 0) {
			if ((rt0 = rt = rtalloc1(dst, 1)))
				rt->rt_refcnt--;
			else {
#ifdef WV_INSTRUMENTATION
#ifdef INCLUDE_WVNET    /* WV_NET_CRITICAL event */
            WV_NET_DSTADDROUT_EVENT_1 (NET_CORE_EVENT, WV_NET_CRITICAL, 4, 5,
                            ((struct sockaddr_in *)dst)->sin_addr.s_addr,
                            WV_NETEVENT_ETHEROUT_NOROUTE, WV_NET_SEND,
                            ((struct sockaddr_in *)dst)->sin_addr.s_addr)
#endif  /* INCLUDE_WVNET */
#endif

                             senderr(EHOSTUNREACH);
                             }
		}
		if (rt->rt_flags & RTF_GATEWAY) {
			if (rt->rt_gwroute == 0)
				goto lookup;
			if (((rt = rt->rt_gwroute)->rt_flags & RTF_UP) == 0) {
				rtfree(rt); rt = rt0;
			lookup: rt->rt_gwroute = rtalloc1(rt->rt_gateway, 1);
				if ((rt = rt->rt_gwroute) == 0) {
#ifdef WV_INSTRUMENTATION
#ifdef INCLUDE_WVNET    /* WV_NET_CRITICAL event */
            WV_NET_DSTADDROUT_EVENT_1 (NET_CORE_EVENT, WV_NET_CRITICAL, 4, 5,
                       ((struct sockaddr_in *)rt->rt_gateway)->sin_addr.s_addr,
                                    WV_NETEVENT_ETHEROUT_NOROUTE, WV_NET_SEND,
                       ((struct sockaddr_in *)rt->rt_gateway)->sin_addr.s_addr)
#endif  /* INCLUDE_WVNET */
#endif
                                    senderr(EHOSTUNREACH);
                                }
			}
		}
		if (rt->rt_flags & RTF_REJECT)
			if (rt->rt_rmx.rmx_expire == 0 ||
			    tickGet() < rt->rt_rmx.rmx_expire) {
#ifdef WV_INSTRUMENTATION
#ifdef INCLUDE_WVNET    /* WV_NET_CRITICAL event */
        WV_NET_EVENT_0 (NET_CORE_EVENT, WV_NET_CRITICAL, 5, 6,
                        WV_NETEVENT_ETHEROUT_RTREJECT, WV_NET_SEND)
#endif  /* INCLUDE_WVNET */
#endif
                            senderr(rt == rt0 ? EHOSTDOWN : EHOSTUNREACH);
                            }
	}
	switch (dst->sa_family) {

#ifdef INET
	case AF_INET:
		if (!arpresolve(ac, rt, m, dst, edst))
			return (0);	/* if not yet resolved */
		/* If broadcasting on a simplex interface, loopback a copy */
		if ((m->m_flags & M_BCAST) && (ifp->if_flags & IFF_SIMPLEX))
			ip_mloopback (ifp, m, (struct sockaddr_in *)dst,
				      (struct rtentry*)rt);
		off = m->m_pkthdr.len - m->m_len;
		etype = ETHERTYPE_IP;
		break;
#endif
	case AF_UNSPEC:
		eh = (struct ether_header *)dst->sa_data;
 		bcopy((caddr_t)eh->ether_dhost, (caddr_t)edst, sizeof (edst));
		etype = eh->ether_type;
		break;

	default:
		printf("%s%d: can't handle af%d\n", ifp->if_name, ifp->if_unit,
			dst->sa_family);
#ifdef WV_INSTRUMENTATION
#ifdef INCLUDE_WVNET    /* WV_NET_ERROR event */
                WV_NET_EVENT_1 (NET_CORE_EVENT, WV_NET_ERROR, 3, 7,
                                WV_NETEVENT_ETHEROUT_AFNOTSUPP, WV_NET_SEND,
                                dst->sa_family)
#endif  /* INCLUDE_WVNET */
#endif
		senderr(EAFNOSUPPORT);
	}

	/*
	 * Add local net header.  If no space in first mbuf,
	 * allocate another.
	 */
	M_PREPEND(m, sizeof (struct ether_header), M_DONTWAIT);

	if (m == 0)
            {
#ifdef WV_INSTRUMENTATION
#ifdef INCLUDE_WVNET    /* WV_NET_CRITICAL event */
            WV_NET_EVENT_1 (NET_CORE_EVENT, WV_NET_CRITICAL, 3, 4,
                            WV_NETEVENT_ETHEROUT_NOBUFS, WV_NET_SEND, ifp)
#endif  /* INCLUDE_WVNET */
#endif

            senderr(ENOBUFS);
            }

	eh = mtod(m, struct ether_header *);
	etype = htons(etype);
	bcopy((caddr_t)&etype,(caddr_t)&eh->ether_type,
		sizeof(eh->ether_type));
 	bcopy((caddr_t)edst, (caddr_t)eh->ether_dhost, sizeof (edst));
 	bcopy((caddr_t)ac->ac_enaddr, (caddr_t)eh->ether_shost,
	    sizeof(eh->ether_shost));
	s = splimp();
	/*
	 * Queue message on interface, and start output if interface
	 * not yet active.
	 */
	if (IF_QFULL(&ifp->if_snd)) {
		IF_DROP(&ifp->if_snd);
		splx(s);
#ifdef WV_INSTRUMENTATION
#ifdef INCLUDE_WVNET    /* WV_NET_CRITICAL event */
            WV_NET_EVENT_1 (NET_CORE_EVENT, WV_NET_CRITICAL, 3, 4,
                            WV_NETEVENT_ETHEROUT_NOBUFS, WV_NET_SEND, ifp)
#endif  /* INCLUDE_WVNET */
#endif

		senderr(ENOBUFS);
	}
	IF_ENQUEUE(&ifp->if_snd, m);

	if ((ifp->if_flags & IFF_OACTIVE) == 0)
		(*ifp->if_start)(ifp);
	splx(s);
	ifp->if_obytes += len + sizeof (struct ether_header);
	if (m->m_flags & M_MCAST || m->m_flags & M_BCAST)
		ifp->if_omcasts++;

#ifdef WV_INSTRUMENTATION
#ifdef INCLUDE_WVNET    /* WV_NET_NOTICE event */
        WV_NET_EVENT_2 (NET_CORE_EVENT, WV_NET_NOTICE, 3, 12,
                        WV_NETEVENT_ETHEROUT_FINISH, WV_NET_SEND, ifp, error)
#endif  /* INCLUDE_WVNET */
#endif
	return (error);

bad:
	if (m)
		m_freem(m);
	return (error);
}

/*******************************************************************************
*
* do_protocol - check the link-level type field and process IP and ARP data
*
* This routine must not be called at interrupt level.
* Process a received Ethernet packet;
* the packet is in the mbuf chain m without
* the ether header, which is provided separately.
*
* NOMANUAL
*/

void
ether_input(ifp, eh, m)
	struct ifnet *ifp;
	register struct ether_header *eh;
	struct mbuf *m;
{
	u_short 		etype;
	struct arpcom *		ac = (struct arpcom *)ifp;

#ifdef WV_INSTRUMENTATION
#ifdef INCLUDE_WVNET    /* WV_NET_NOTICE event */
        WV_NET_EVENT_1 (NET_CORE_EVENT, WV_NET_NOTICE, 4, 13,
                        WV_NETEVENT_ETHERIN_START, WV_NET_RECV, ifp)
#endif  /* INCLUDE_WVNET */
#endif

	if ((ifp->if_flags & IFF_UP) == 0) {
		m_freem(m);
		return;
	}
	ifp->if_lastchange = tickGet();
	ifp->if_ibytes += m->m_pkthdr.len + sizeof (*eh);
	if (eh->ether_dhost[0] & 1) {
		if (bcmp((caddr_t)etherbroadcastaddr, (caddr_t)eh->ether_dhost,
		    sizeof(etherbroadcastaddr)) == 0)
			m->m_flags |= M_BCAST;
		else
			m->m_flags |= M_MCAST;
		ifp->if_imcasts++;
	}

        if (ifp->if_flags & IFF_PROMISC)
            {
            /*
             * do not hand over the non multicast packets to the ip stack
             * if they are not destined to us, orelse it confuses the
             * ip forwarding logic and keeps sending unnecessary redirects.
             * If packets destined for other hosts have to be snooped they
             * have to done through driver level hooks.
             */
            
            if (!(m->m_flags & (M_BCAST | M_MCAST)))
                {
                if (bcmp ((caddr_t)ac->ac_enaddr, (caddr_t)eh->ether_dhost,
                          sizeof(eh->ether_dhost)) != 0)
                    {
                    m_freem (m); 	/* free the packet chain */
                    return; 
                    }
                }
            }