int sar_CheckPacket(arp_Header *ap)
{
register arp_Header *op;
if ( ap->hwType != wfix(arp_TypeEther) || /* have ethernet hardware, */
ap->protType != wfix(0x800) || /* and internet software, */
ap->opcode != wfix(ARP_REQUEST) || /* and be a resolution req. */
ap->dstIPAddr != lfix(sin_lclINAddr) /* for my addr. */
)
return ( 0 ); /* .... or we ignore it. */
#if CPMAC_DEBUG
sys_printf("ARP REQUEST IS VALID\n");
#endif
/* format response. */
op = (arp_Header *)sed_FormatPacket(ap->srcEthAddr, 0x806);
op->hwType = wfix(arp_TypeEther);
op->protType = wfix(0x800);
op->hwProtAddrLen = wfix((sizeof(eth_HwAddress) << 8) + sizeof(in_HwAddress));
op->opcode = wfix(ARP_REPLY);
op->srcIPAddr = lfix(sin_lclINAddr);
MoveW(sed_lclEthAddr, op->srcEthAddr, sizeof(eth_HwAddress));
ap->dstIPAddr = op->srcIPAddr;
MoveW(ap->srcEthAddr, op->dstEthAddr, sizeof(eth_HwAddress));
sed_Send(sizeof(arp_Header));
#if CPMAC_DEBUG
sys_printf("ARP RESPONSE SENT\n");
#endif
return ( 1 );
}
void TTCP_send_fdf(tcp_Socket *s)
{
tcp_PseudoHeader ph;
struct _pkt {
in_Header in;
tcp_Header tcp;
DWORD maxsegopt;
} *pkt;
BYTE *dp;
pkt = (struct _pkt *)sed_FormatPacket(&s->hisethaddr[0], 0x800);
dp = (BYTE *)&pkt->maxsegopt;
pkt->in.length = sizeof(in_Header) + sizeof(tcp_Header) + s->dataSize;
/* tcp header */
pkt->tcp.srcPort = s->myport;
pkt->tcp.dstPort = s->hisport;
pkt->tcp.seqnum = s->seqnum;
pkt->tcp.acknum = s->acknum;
pkt->tcp.window = 1024;
pkt->tcp.flags = s->flags | 0x5000; /* Header length = 20bytes ;; no option */
pkt->tcp.checksum = 0;
pkt->tcp.urgentPointer = 0;
if ( s->flags & tcp_FlagSYN ) {
pkt->tcp.flags += 0x1000;
pkt->in.length += 4;
pkt->maxsegopt = 0x02040578; /* 1400 bytes */
dp += 4;
}
Move(s->datas, dp, s->dataSize); /* copy data to pointer which is next to tcp header */
/* internet header */
pkt->in.vht = 0x4500; /* version 4, hdrlen 5, tos 0 */
pkt->in.identification = tcp_id++;
pkt->in.frag = 0;
pkt->in.ttlProtocol = (250<<8) + 6;
pkt->in.checksum = 0;
pkt->in.source = sin_lclINAddr;
pkt->in.destination = s->hisaddr;
pkt->in.checksum = ~(checksum((WORD *)&pkt->in, sizeof(in_Header)));
/* compute tcp checksum */
ph.src = pkt->in.source;
ph.dst = pkt->in.destination;
ph.mbz = 0;
ph.protocol = 6;
ph.length = pkt->in.length - sizeof(in_Header);
ph.checksum = checksum((WORD *)&pkt->tcp, ph.length);
pkt->tcp.checksum = ~checksum((WORD *)&ph, sizeof ph);
sed_Send(pkt->in.length);
}
int sar_MapIn2Eth(longword ina, eth_HwAddress *ethap)
{
register arp_Header *op;
extern in_HwAddress sin_lclINAddr;
longword endTime;
longword rxMitTime;
endTime = clock_ValueRough() + 2000;
while ( endTime > clock_ValueRough() )
{
op = (arp_Header *)sed_FormatPacket(&sed_ethBcastAddr[0], 0x806);
op->hwType = wfix(arp_TypeEther);
op->protType = wfix(0x800);
op->hwProtAddrLen = wfix((sizeof(eth_HwAddress) << 8) + sizeof(in_HwAddress));
op->opcode = wfix(ARP_REQUEST);
op->srcIPAddr = lfix(sin_lclINAddr);
MoveW(sed_lclEthAddr, op->srcEthAddr, sizeof(eth_HwAddress));
if ((ina&net_IpMask)!=(sin_lclINAddr&net_IpMask))
ina=net_Gateway;
op->dstIPAddr = lfix(ina);
/* ...and send the packet */
sed_Send( sizeof(arp_Header) );
rxMitTime = clock_ValueRough() + 500;
while ( rxMitTime > clock_ValueRough() )
{
op = (arp_Header *)sed_IsPacket();
if ( op )
{
if ((sed_CheckPacket(op, 0x806) == 1) &&
(op->protType == wfix(0x800)) &&
(op->srcIPAddr == lfix(ina)) &&
(op->opcode == wfix(ARP_REPLY)) )
{
MoveW(op->srcEthAddr, ethap, sizeof(eth_HwAddress));
return ( 1 );
}
}
}
}
return ( 0 );
}
/*
* Format and send an outgoing reset segment
*/
void tcp_Reset( in_Header *ip, tcp_Header *tp )
{
tcp_PseudoHeader ph;
struct _pkt {
in_Header in;
tcp_Header tcp;
DWORD maxsegopt;
} *pkt;
pkt = (struct _pkt *)sed_FormatPacket(&(((eth_Header *)ip)-1)->source[0], 0x800);
pkt->in.length = sizeof(in_Header) + sizeof(tcp_Header);
/* tcp header */
pkt->tcp.srcPort = tp->dstPort;
pkt->tcp.dstPort = tp->srcPort;
pkt->tcp.seqnum = tp->seqnum;
pkt->tcp.acknum = tp->acknum;
pkt->tcp.window = 1024;
pkt->tcp.flags = tcp_FlagRST | 0x5000; /* Header length = 20bytes ;; no option */
pkt->tcp.checksum = 0;
pkt->tcp.urgentPointer = 0;
/* internet header */
pkt->in.vht = 0x4500; /* version 4, hdrlen 5, tos 0 */
pkt->in.identification = tcp_id++;
pkt->in.frag = 0;
pkt->in.ttlProtocol = (250<<8) + 6;
pkt->in.checksum = 0;
pkt->in.source = sin_lclINAddr;
pkt->in.destination = ip->source;
pkt->in.checksum = ~(checksum((WORD *)&pkt->in, sizeof(in_Header)));
/* compute tcp checksum */
ph.src = pkt->in.source;
ph.dst = pkt->in.destination;
ph.mbz = 0;
ph.protocol = 6;
ph.length = pkt->in.length - sizeof(in_Header);
ph.checksum = checksum((WORD *)&pkt->tcp, ph.length);
pkt->tcp.checksum = ~checksum((WORD *)&ph, sizeof ph);
sed_Send(pkt->in.length);
}
