ping.c

嵌入式RMON,RMON为Remote monitor的缩写,基于SNMP为网络提供主动监控及错误告警,智能交换路由必备协议

/* Beholder RMON ethernet network monitor,Copyright (C) 1993 DNPAP group */
/* See file COPYING 'GNU General Public Licence' for copyright details   */
#include <chain.h>
#include <icmp.h>
#include <ip.h>
#include <timer.h>
#include <dtime.h>
#include "ping.h"




static VOID TimerCallback(TIMER_DESCR *timer, ULONG now, void *parm);
static BOOLEAN IcmpCallback(ICMP_DESCR *icmp, CHAIN *chain,
            ICMP_HDR *icmpHdr, IP_HDR *ipHdr);



PING_DESCR *PingSend(DWORD addr, ULONG timeout, USHORT length, USHORT seqnr,
                PING_CALLBACK callback, VOID *parm)
{
    ICMP_DESCR   *icmp;
    TIMER_DESCR *timer;
    PING_DESCR  *ping;

    CHAIN       *chain; 
    
    ICMP_HDR     icmpHdr;
    IP_HDR      ipHdr;


  
    ping=DnpapMalloc(sizeof(PING_DESCR));
    if (ping==0)
    {
        return 0;
    }
    ping->parm=parm;
    ping->callback=callback;
    ping->seqnr=seqnr;
    ping->length=length;
    ping->start=0;
    ping->timer=0;
    ping->icmp=0;



    icmp=DnpapMalloc(sizeof(ICMP_DESCR));
    if (icmp==0)
    {
        DnpapFree(ping);
        return 0;
    }
    icmp->Rcve=IcmpCallback;
    icmp->type=ICMP_ECHO_REPLY;
    icmp->code=ICMP_CODE_ANY;
    icmp->id=IcmpAnyId();
    icmp->seqnr=ICMP_SEQNR_ANY;
    icmp->remAddr=addr; 
#ifdef OS2
    icmp->locAddr=IpRouteFindSrc(addr);
#else   
    icmp->locAddr=ICMP_ADDR_ANY;   
#endif
    icmp->specific=ping;
    if (!IcmpRegister(icmp))
    {
        DnpapFree(icmp);
        DnpapFree(ping);
        return 0;
    }
    ping->icmp=icmp;


    
    timer=TimerRegister(TimerCallback, ping, timeout, TIMER_FOREVER, TIMER_TYPE_SKIP);
    if (timer==0)
    {
        IcmpRemove(icmp);
        DnpapFree(icmp);
        DnpapFree(ping);
        return 0;
    }
    ping->timer=timer;


    
    chain = ChainAlloc(0,0,length+34,length,34,0);
    if (chain==0)
    {
        TimerRemove(ping->timer);
        IcmpRemove(ping->icmp);
        DnpapFree(ping->icmp);
        DnpapFree(ping);
        return 0;
    }



    ipHdr.src=icmp->locAddr;
    ipHdr.dst=icmp->remAddr;
    ipHdr.options=0;
    ipHdr.iol=0;

    icmpHdr.type=ICMP_ECHO_REQUEST;
    icmpHdr.code=0;
    icmpHdr.id=icmp->id;
    icmpHdr.seqnr=seqnr;
    
    ping->start=TimeUsec();
    
    if (!IcmpSend(chain, &icmpHdr, &ipHdr))
    {
        ChainFree(chain);
        TimerRemove(ping->timer);
        IcmpRemove(ping->icmp);
        DnpapFree(ping->icmp);
        DnpapFree(ping);
        return 0;
    }

    ChainFree(chain);
    return ping;
}



VOID PingAbort(PING_DESCR *ping)
{
    if (ping==0)
        return;
    
    TimerRemove(ping->timer);
    IcmpRemove(ping->icmp);
    DnpapFree(ping->icmp);
    DnpapFree(ping);
}



static VOID TimerCallback(TIMER_DESCR *timer, ULONG now, void *parm)
{
    PING_DESCR *ping;
    
    

    ping = parm;

    ping->callback(ping, -1UL, ping->seqnr, ping->parm);

    PingAbort(ping);
}


static BOOLEAN IcmpCallback(ICMP_DESCR *icmp, CHAIN *chain,
            ICMP_HDR *icmpHdr, IP_HDR *ipHdr)
{
    PING_DESCR *ping;
    
    ping = icmp->specific;

    if (icmpHdr->seqnr!=ping->seqnr)
    {
        DnpapMessage(DMC_WARNING, PING_ERROR, "Wrong sequence number");
        return TRUE;
    }
    
    if (ChainLength(chain)!=ping->length)
    {
        DnpapMessage(DMC_WARNING, PING_ERROR, "Wrong length");
        return TRUE;
    }

    ping->callback(ping, TimeUsec()-ping->start, ping->seqnr, ping->parm);

    PingAbort(ping);

    return TRUE;
}