#include "all.h"
#include "mem.h"
#include "../ip/ip.h"
enum /* Packet Types */
{
EchoReply = 0,
Unreachable = 3,
SrcQuench = 4,
EchoRequest = 8,
TimeExceed = 11,
Timestamp = 13,
TimestampReply = 14,
InfoRequest = 15,
InfoReply = 16,
};
void
icmprecv(Msgbuf *mb, Ifc *ifc)
{
Icmppkt *p;
uchar tmp[Pasize];
p = (Icmppkt*)mb->data;
switch(p->icmptype) {
default:
goto drop;
case EchoRequest:
memmove(tmp, p->src, Pasize);
memmove(p->src, p->dst, Pasize);
memmove(p->dst, tmp, Pasize);
p->icmptype = EchoReply;
p->icmpsum[0] = 0;
p->icmpsum[1] = 0;
hnputs(p->icmpsum,
ptclcsum((uchar*)mb->data+(Ensize+Ipsize),
mb->count-(Ensize+Ipsize)));
/* note that tmp contains dst */
if((nhgetl(ifc->ipa)&ifc->mask) != (nhgetl(p->dst)&ifc->mask))
iproute(tmp, p->dst, ifc->netgate);
ipsend1(mb, ifc, tmp);
break;
}
return;
drop:
mbfree(mb);
}
void
igmprecv(Msgbuf *mb, Ifc*)
{
mbfree(mb);
}
void
tcprecv(Msgbuf *mb, Ifc*)
{
mbfree(mb);
}
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