if_ether.c

VXWORKS源代码

/* if_ether.c - network Ethernet address resolution protocol */

/* Copyright 1984 - 2002 Wind River Systems, Inc. */
#include "copyright_wrs.h"

/*
 * Copyright (c) 1982, 1986, 1988, 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_ether.c	8.2 (Berkeley) 9/26/94
 */

/*
 * Ethernet address resolution protocol.
 * TODO:
 *	add "inuse/lock" bit (or ref. count) along with valid bit
 */

/*
modification history
--------------------
01u,24jun02,wap  optimize away some bcopy()s in arpresolve()
01t,21may02,vvv  fixed ARP timer overflow problem (SPR #63908)
01s,24jan02,vvv  fixed arpintr memory leak (SPR #72577)
01r,18dec01,vvv  fixed build error from previous check-in
01q,18dec01,vvv  fixed shared-memory booting problem (SPR #71023)
01p,10dec01,vvv  allow send to any address assigned to an interface (SPR #71836)
01o,01nov01,rae  compiler warnings, modified arpresolve error message (SPR #71242)
01n,12oct01,rae  merge from truestack ver 01z base 01j (SPRs 63006, 68954,
                 69112 ... plus Fastpath, revarp, etc.)
01m,07feb01,spm  added merge record for 30jan01 update from version 01i of
                 tor2_0_x branch (base 01h) and fixed modification history
01l,30jan01,ijm  merged SPR# 28602 fixes (proxy ARP services are obsolete);
                 fixed deleting ARP entries when proxy flag set
01j,08nov99,pul  merging T2 cumulative patch 2
01k,08Nov98,pul  changed the argument ordering to ipEtherResolveRtn
01i,29apr99,pul  Upgraded NPT phase3 code to tor2.0.0
01h,10may99,spm  fixed SIOCSARP handling to support ATF_PUBL flag (SPR #24397)
01g,03sep98,n_s  fixed handling of IFF_NOARP flag in arpresolve. spr #22280
01g,13jul98,n_s  added arpRxmitTicks.  spr # 21577
01f,10jul97,vin  ifdefed revarp code, fixed warnings.
01e,23apr97,vin  fixed SPR8445, rt_expire for arp route entry being set to 0.
01d,29jan97,vin  fixed a bug in arpioctl(), sdl_alen field.
01c,16dec96,vin  removed unnecessary htons in arprequest() and arpinput().
01b,31oct96,vin	 changed m_gethdr(..) to mHdrClGet(..).  
01a,03mar96,vin  created from BSD4.4 stuff,integrated with 02n of if_ether.c
*/

/*
 * Ethernet address resolution protocol.
 * TODO:
 *      run at splnet (add ARP protocol intr.)
 *      link entries onto hash chains, keep free list
 *      add "inuse/lock" bit (or ref. count) along with valid bit
 */
#include "vxWorks.h"
#include "logLib.h"
#include "stdio.h"

#include "net/mbuf.h"
#include "sys/socket.h"
#include "errno.h"
#include "sys/ioctl.h"

#include "net/if.h"
#include "net/if_dl.h"
#include "net/route.h"
#include "netinet/in.h"
#include "netinet/in_systm.h"
#include "netinet/in_var.h"
#include "netinet/ip.h"
#include "netinet/if_ether.h"
#include "wdLib.h"
#include "tickLib.h"
#include "net/systm.h"

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

#ifdef ROUTER_STACK
#include "wrn/fastPath/fastPathLib.h"
#include "wrn/fastPath/fastPathIpP.h"
#endif /* ROUTER_STACK */

#ifdef INET

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

/* defines */

/* defines */

#define ENET_SIZE		6		/* Ethernet address size */

#define DDB

#define PROXY_HOOK		/* include proxy hook code */

#define SIN(s) ((struct sockaddr_in *)s)
#define SDL(s) ((struct sockaddr_dl *)s)
#define SRP(s) ((struct sockaddr_inarp *)s)

/*
 * ARP trailer negotiation.  Trailer protocol is not IP specific,
 * but ARP request/response use IP addresses.
 */
#define ETHERTYPE_IPTRAILERS ETHERTYPE_TRAIL

#define	rt_expire rt_rmx.rmx_expire

#define ARP_RXMIT_TICKS_DFLT sysClkRateGet ()      /* Minimum number of ticks */
					           /* between retransmission  */
						   /* of ARP request          */
#define TICK_GEQ(t1,t2) ((long)((t1) - (t2)) >= 0)

/* externs */

IMPORT STATUS netJobAdd (FUNCPTR, int, int, int, int, int);
IMPORT int sysClkRateGet ();


#ifndef VIRTUAL_STACK
extern struct ifnet loif[];
#endif /* VIRTUAL_STACK */

extern  void _insque ();
extern  void _remque ();
int arpMaxEntries = 12;                      /* sensible default */

/* globals */

void arptfree (struct llinfo_arp *);

#ifndef VIRTUAL_STACK
struct	llinfo_arp llinfo_arp = {&llinfo_arp, &llinfo_arp};
int	arp_inuse, arp_allocated, arp_intimer;
int	arpinit_done = 0;
#endif /* VIRTUAL_STACK */

struct	ifqueue arpintrq = {0, 0, 0, 50};

int	useloopback = 1;
int	arp_maxtries = 5; /* use loopback interface for local traffic */

/* timer values */
int	arpt_prune = (1*60);	/* walk list every 1 minutes */
int	arpt_keep = (20*60);	/* once resolved, good for 20 more minutes */
int	arpt_down = 20;		/* once declared down, don't send for 20 secs */

#ifndef VIRTUAL_STACK
int arpRxmitTicks = -1; 	/* Minimum number of ticks between */
				/* retranmission of ARP request    */
#endif /* VIRTUAL_STACK */

/* proxy arp hook */

#ifdef PROXY_HOOK
FUNCPTR	 proxyArpHook = NULL;
#endif

/* locals */

#ifndef VIRTUAL_STACK
LOCAL WDOG_ID arptimerWd; /* watchdog timer for arptimer routine */
#endif /* VIRTUAL_STACK */

static char 	digits[] = "0123456789abcdef";

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

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

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

/* forward declarations */

#ifdef VIRTUAL_STACK
void arptimer (int);
#else
static	void arptimer (void *);
#endif /* VIRTUAL_STACK */
static	void arprequest (struct arpcom *, u_long *, u_long *, u_char *);
static	struct llinfo_arp *arplookup (u_long, int, int);
static	void in_arpinput (struct mbuf *);
static  void arpEntryDelete (void);

/*
 * Timeout routine.  Age arp_tab entries periodically.
 */
/* ARGSUSED */
#ifdef VIRTUAL_STACK
/* must have a helper routine because of argument limitations */
/* in WdStart */
void arptimerRestart
    (
    int stackNum
    )
    {
    netJobAdd ((FUNCPTR)arptimer, stackNum, 0, 0, 0, 0);
    }

void arptimer
    (
    int stackNum    /* used to set the stack correctly in wd routine*/
    )
    {
    int s;
    register struct llinfo_arp *la;
    virtualStackNumTaskIdSet(stackNum);

    s = splnet();

    la = _llinfo_arp.la_next;
    wdStart (arptimerWd, arpt_prune * sysClkRateGet(),
             (FUNCPTR) arptimerRestart, (int) stackNum);
    while (la != &_llinfo_arp)
        {
	register struct rtentry *rt = la->la_rt;
	la = la->la_next;
	if (rt->rt_expire && rt->rt_expire <= tickGet())
	    {
	    arptfree(la->la_prev); /* timer has expired; clear */
	    }
	}
    splx (s);
    }

#else  /* just use original version */
static void
arptimer(arg)
	void *arg;
    {
    int s = splnet();
    register struct llinfo_arp *la = llinfo_arp.la_next;

    wdStart (arptimerWd, arpt_prune * sysClkRateGet(), (FUNCPTR) netJobAdd,
	     (int)arptimer);

    while (la != &llinfo_arp) 
	{
	register struct rtentry *rt = la->la_rt;
	la = la->la_next;
	if (rt->rt_expire && TICK_GEQ (tickGet(), rt->rt_expire))
	    {
#ifdef WV_INSTRUMENTATION
#ifdef INCLUDE_WVNET    /* WV_NET_INFO event */
            WV_NET_MARKER_0 (NET_AUX_EVENT, WV_NET_INFO, 2, 15,
                             WV_NETEVENT_ARPTIMER_FREE)
#endif  /* INCLUDE_WVNET */
#endif

	    arptfree(la->la_prev); /* timer has expired; clear */
	    }
	}
    splx (s);
    }
#endif /* VIRTUAL_STACK */

/* IP multicast address to Ethernet mulitcast address mapping */

void ipToEtherMCastMap
     ( 
     struct in_addr * ipaddr,
     u_char *         enaddr
     )
     {
     enaddr[0] = 0x01;
     enaddr[1] = 0x00;
     enaddr[2] = 0x5e;
     enaddr[3] = ((u_char *)ipaddr)[1] & 0x7f;
     enaddr[4] = ((u_char *)ipaddr)[2];
     enaddr[5] = ((u_char *)ipaddr)[3];
     return;
     }

/* IP to Ethernet address resolution protocol. This is just a wrapper for arpresolve
* being called from ipOutput. This routine calls arpresolve with the appropriate
* set of arguments. 
*
* Returns 1 if the address is resolved and 0 if the address is not resolved.
*/

int ipEtherResolvRtn
    (
    FUNCPTR           ipArpCallBackRtn,
    struct mbuf *     pMbuf,
    struct sockaddr * dstIpAddr,
    struct ifnet *    ifp,
    struct rtentry *  rt,
    char *            dstBuff
    )
    {
    return(arpresolve ((struct arpcom *)ifp, rt, pMbuf, dstIpAddr, dstBuff));
    }


/*
 * Parallel to llc_rtrequest.
 */
void
arp_rtrequest(req, rt, sa)
	int req;
	register struct rtentry *rt;
	struct sockaddr *sa;
{
	register struct sockaddr *gate = rt->rt_gateway;
	register struct llinfo_arp *la = (struct llinfo_arp *)rt->rt_llinfo;
	static struct sockaddr_dl null_sdl = {sizeof(null_sdl), AF_LINK};
	struct ifaddr *ifAddr = NULL;

#ifdef WV_INSTRUMENTATION
#ifdef INCLUDE_WVNET    /* WV_NET_VERBOSE event */
        WV_NET_MARKER_1 (NET_AUX_EVENT, WV_NET_VERBOSE, 7, 17,
                         WV_NETEVENT_ARPRTREQ_START, req)
#endif  /* INCLUDE_WVNET */
#endif

#ifndef VIRTUAL_STACK
	if (!arpinit_done) {
	/*
	 * if this routine is executed for the first time, then 
	 * create the watch dog timer and kick of the arp timer.
	 */
		arpinit_done = 1;
		arptimerWd = wdCreate ();
		netJobAdd ((FUNCPTR)arptimer, 0, 0, 0, 0, 0);
	}
#endif /* VIRTUAL_STACK */
	if (rt->rt_flags & RTF_GATEWAY)
		return;
	switch (req) {

	case RTM_ADD:
		/*
		 * XXX: If this is a manually added route to interface
		 * such as older version of routed or gated might provide,
		 * restore cloning bit.
		 */
		if ((rt->rt_flags & RTF_HOST) == 0 &&
		    SIN(rt_mask(rt))->sin_addr.s_addr != 0xffffffff)
			rt->rt_flags |= RTF_CLONING;

		if (rt->rt_flags & RTF_CLONING) {
			/*
			 * Case 1: This route should come from a route to iface.
			 */

			rt_setgate(rt, rt_key(rt),
					(struct sockaddr *)&null_sdl);
			gate = rt->rt_gateway;
			SDL(gate)->sdl_type = rt->rt_ifp->if_type;
			SDL(gate)->sdl_index = rt->rt_ifp->if_index;
			/*
			 * Give this route an expiration time, even though
			 * it's a "permanent" route, so that routes cloned
			 * from it do not need their expiration time set.
			 */
			rt->rt_expire = tickGet();
                        /*
                         * rt_expire could be zero if the interface is
                         * initialized before the first tick of the system
                         * typically 1/60th of a second.
                         * All the arp routes cloned from this route will
                         * inherit all the route metrics properties.
                         * if rt_expire is 0 for an arp route entry,
                         * it never kicks in arpwhohas () in arpresolve ().
                         * This would result in not generating an arp request
                         * for the host. This problem was seen on the MIPS
                         * board p4000. --- Vinai. Fix for SPR 8445
                         */
                        if (rt->rt_expire == 0)
                            rt->rt_expire++;

			break;