📄 packet.c
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if (fLease) {
if (NewLease < MIN_LEASE_TIME && Type == DHCPACK) {
DEBUGMSG(ZONE_RECV, (TEXT("DHCP:TranslatePkt: Invalid lease time %d < %d\n"), NewLease, MIN_LEASE_TIME));
goto BreakLoop;
}
} else {
if (Type == DHCPACK) {
DEBUGMSG(ZONE_RECV, (TEXT("DHCP:TranslatePkt: No lease specified in DHCPACK!\n")));
goto BreakLoop;
}
}
if (fServer) {
if (NewServer == 0) {
DEBUGMSG(ZONE_RECV, (TEXT("DHCP:TranslatePkt: Invalid server id %d\n"), NewServer));
goto BreakLoop;
}
}
//
// Make sure the ipaddr and subnet mask match if this is a renewal
//
if (*pType == DHCPACK && pDhcp->IPAddr) {
if (pDhcp->IPAddr != pPkt->Yiaddr) {
DEBUGMSG(ZONE_RECV,(TEXT("DHCP:TranslatePkt: Mismatch in IP addr - rcvd 0x%X, expect 0x%X\r\n"),
pPkt->Yiaddr,pDhcp->IPAddr));
goto BreakLoop;
}
if (pDhcp->SubnetMask != NewSubnetMask) {
DEBUGMSG(ZONE_RECV,(TEXT("DHCP:TranslatePkt: Mismatch in subnet - rcvd 0x%X, expect 0x%X\r\n"),
NewSubnetMask,pDhcp->SubnetMask));
goto BreakLoop;
}
}
//
// Open registry key to save new values
//
if (DHCPACK == Type) {
_tcscpy (szBuf, COMM_REG_KEY);
_tcscat (szBuf, pDhcp->Name);
_tcscat (szBuf, TEXT("\\Parms\\TcpIp\\DhcpOptions"));
hRes = RegOpenKeyEx (HKEY_LOCAL_MACHINE, szBuf, 0, 0,
&hKey);
if (ERROR_SUCCESS == hRes) {
DEBUGMSG(ZONE_RECV,
(TEXT("DHCP:TranslatePacket: Save in registry\r\n")));
fSaveReg = TRUE;
}
}
//
// Now run through the options again and store away results
//
p = &pPkt->aOptions[4];
while (p < (char *)pPkt + cPkt) {
switch(*p) {
case DHCP_PAD_OP:
p++;
continue;
break;
case DHCP_END_OP:
Status = DHCP_SUCCESS;
goto BreakLoop;
break;
case DHCP_SUBNET_OP:
pDhcp->SubnetMask = NewSubnetMask;
break;
case DHCP_ROUTER_OP:
pDhcp->Gateway = NewGateway;
break;
case DHCP_DNS_OP:
pDhcp->DNS[0] = NewDNS[0];
pDhcp->DNS[1] = NewDNS[1];
break;
case DHCP_DOMAIN_NAME_OP:
if (p[1] > MAX_DOMAIN_NAME)
p[1] = (uchar)MAX_DOMAIN_NAME;
memcpy(pDhcp->aDomainName, p+1, p[1] + 1);
break;
case DHCP_NBT_SRVR_OP:
pDhcp->WinsServer[0] = NewWins[0];
pDhcp->WinsServer[1] = NewWins[1];
break;
case DHCP_IP_LEASE_OP:
pDhcp->Lease = net_long(NewLease);
break;
case DHCP_SERVER_ID_OP:
pDhcp->DhcpServer = NewServer;
break;
case DHCP_T1_VALUE_OP:
pDhcp->T1 = net_long(NewT1);
break;
case DHCP_T2_VALUE_OP:
pDhcp->T2 = net_long(NewT2);
break;
case DHCP_MSFT_AUTOCONF:
if (p[2]) {
pDhcp->Flags |= AUTO_IP_ENABLED_FL;
} else {
pDhcp->Flags &= ~AUTO_IP_ENABLED_FL;
}
break;
case DHCP_OVERLOAD_OP:
ASSERT(0); break;
case DHCP_MSG_TYPE_OP:
case DHCP_MESSAGE_OP: // NYI
case DHCP_NBT_NODE_TYPE_OP: // NYI
case DHCP_HOST_NAME_OP: // NYI
break;
default:
DEBUGMSG(ZONE_RECV,
(TEXT("DHCP:TranslatePkt: Unexpected option %d\r\n"), *p));
break;
} // switch(*p)
if (fSaveReg) {
Tvert(*p, szBuf);
cData = 0;
hRes = RegQueryValueEx(hKey, szBuf, NULL, NULL, NULL, &cData);
if (ERROR_SUCCESS == hRes && cData)
SetRegBinaryValue(hKey, szBuf, p, p[1] + 2);
}
p += p[1] + 2;
} // while (...)
DEBUGMSG(ZONE_RECV, (TEXT("DHCP:TranslatePkt: No DHCP_END_OP in packet!!\n")));
BreakLoop:
if (Status == DHCP_SUCCESS && (Type == DHCPOFFER || Type == DHCPACK)) {
if (fLease) {
if (! fT1)
pDhcp->T1 = pDhcp->Lease >> 1; // default half lease time
if (! fT2)
pDhcp->T2 = (pDhcp->Lease * 7) >> 3; // dft: 7/8 lease time
memcpy(&pDhcp->IPAddr, &pPkt->Yiaddr, 4);
}
}
} else {
#if DEBUG
if (cPkt < (sizeof(*pPkt) - OPTIONS_LEN + 4))
DEBUGMSG(ZONE_RECV,
(TEXT("DHCP:Translate: packet too small %d\r\n"),
cPkt));
// we can continue--since pPkt is a ptr to our own packet which we know is
// larger than the minimum dhcp packet
if (2 != pPkt->Op)
DEBUGMSG(ZONE_RECV, (TEXT("DHCP:TranslatePkt: Op %d != 2\n"),
pPkt->Op));
if (1 != pPkt->Htype)
DEBUGMSG(ZONE_RECV,
(TEXT("DHCP:TranslatePkt: Htype %d != 1\n"), pPkt->Htype));
if (Xid != pPkt->Xid)
DEBUGMSG(ZONE_RECV,
(TEXT("DHCP:TranslatePkt: Xid 0x%x != 0x%x\n"), pPkt->Xid, Xid));
if (0 != memcmp(&Cookie, pPkt->aOptions, 4))
DEBUGMSG(ZONE_RECV,
(TEXT("DHCP:TranslatePkt: Cookie %B%B%B%B != %X\n"),
pPkt->aOptions[3], pPkt->aOptions[2], pPkt->aOptions[1],
pPkt->aOptions[0], Cookie));
#endif
}
if (fSaveReg)
RegCloseKey(hKey);
if (pType)
*pType = Type;
DEBUGMSG(ZONE_RECV, (TEXT("DHCP:-TranslatePkt: pDhcp %X Type %d, Ret: %d\r\n"),
pDhcp, Type, Status));
return Status;
} // TranslatePkt()
STATUS DhcpSendDown(DhcpInfo *pDhcp, DhcpPkt *pPkt, int cPkt, int DestIP) {
SOCKADDR_IN SockAddr;
STATUS Status;
int cSent;
if (cPkt < 300)
cPkt = 300;
memset(&SockAddr, 0, sizeof(SockAddr));
SockAddr.sin_family = AF_INET;
SockAddr.sin_port = net_short(DHCP_SERVER_PORT);
SockAddr.sin_addr.S_un.S_addr = DestIP;
Status = CallSock(Send)(pDhcp->Socket, (char *)pPkt, cPkt,
0, (SOCKADDR *)&SockAddr, sizeof(SockAddr), &cSent, NULL);
DEBUGMSG(ZONE_SEND,
(TEXT("*DhcpSendDown: Dest %d/%x, Sent %d/%d Status %d\r\n"),
DHCP_SERVER_PORT, pDhcp->IPAddr, cSent,
cPkt, Status));
return Status;
} // DhcpSendDown()
#define MAX_LOOP 4
STATUS SendDhcpPkt(DhcpInfo *pDhcp, DhcpPkt *pPkt, int cPkt,
uchar WaitforType, int Flags) {
STATUS Status = DHCP_FAILURE;
int cLoop, cTimeLeft, cTimeout, cMultiplier;
int cFuzz = 0;
DWORD cBeginTime, cZeroTime;
struct timeval Timeval;
LPSOCK_INFO Sock;
SOCK_LIST ReadList;
DhcpPkt RcvPkt;
int cRcvd, cRcvPkt;
uchar Type;
int fSend = TRUE;
int cMaxLoop;
int DestIP;
DEBUGMSG(ZONE_SEND, (TEXT("+SendDhcpPkt: pDhcp %X pPkt %X\r\n"),
pDhcp, pPkt));
Sock = pDhcp->Socket;
if (BCAST_FL & Flags)
DestIP = INADDR_BROADCAST;
else
DestIP = pDhcp->DhcpServer;
cRcvPkt = sizeof(RcvPkt);
CTEFreeLock(&pDhcp->Lock, 0);
cMaxLoop = Flags & LOOP_MASK_FL;
cLoop = 0;
if (pDhcp->Flags & AUTO_IP_ENABLED_FL) {
cTimeout = 1500;
cMultiplier = 1;
} else {
cTimeout = 4000;
cMultiplier = 2;
}
cZeroTime = GetTickCount();
// add random fuzz of +/- 1 sec.
cFuzz = (GetTickCount() % 2000) - 1000;
cTimeLeft = cTimeout + cFuzz;
pDhcp->SFlags &= ~DHCPSTATE_SAW_DHCP_SRV;
do {
cBeginTime = GetTickCount();
if (fSend) {
pPkt->Secs = (unsigned short)((cBeginTime - cZeroTime) / 1000);
if (Status = DhcpSendDown(pDhcp, pPkt, cPkt, DestIP))
break;
}
// wait only 8 secs (2 x min time) after last packet
if ((cLoop != 1) && ((cLoop + 1) == cMaxLoop) && (cTimeLeft > 8000))
cTimeLeft = 8000 + cFuzz;
ASSERT((cTimeLeft >= 0) && (cTimeLeft < 62000));
if (cTimeLeft < 0)
cTimeLeft = 0;
if (cTimeLeft > 62000)
cTimeLeft = 62000;
// do select w/ timeout
Timeval.tv_sec = cTimeLeft / 1000;
Timeval.tv_usec = (cTimeLeft % 1000)*1000;
ReadList.hSocket = 0;
ReadList.Socket = Sock;
ReadList.EventMask = READ_EVENTS;
Status = CallAfd(Select)(1, &ReadList, 0, NULL, 0, NULL, &Timeval, NULL);
if (Status)
break;
if (ReadList.Socket) { // there is data
cRcvPkt = sizeof(RcvPkt);
Status = CallSock(Recv)(Sock, (char *)&RcvPkt, cRcvPkt, 0, NULL, NULL, &cRcvd, NULL);
if (Status) {
DEBUGMSG(ZONE_SEND, (TEXT("SendDhcpPkt: Recv() failed %d\n"), Status));
break;
}
Type = WaitforType;
Status = TranslatePkt(pDhcp, &RcvPkt, cRcvd, &Type, pPkt->Xid);
if (DHCP_SUCCESS == Status) {
if (Type == WaitforType)
break;
else if (DHCPNACK == Type) {
Status = DHCP_NACK;
break;
}
}
// this should work as long as the difference is not huge
cTimeLeft -= GetTickCount() - cBeginTime;
} else { // Select timed out
DEBUGMSG(ZONE_SEND, (TEXT("SendDhcpPkt: Select() timed out\n")));
Status = DHCP_FAILURE;
cTimeLeft = 0;
}
if (cTimeLeft <= 0) {
cFuzz = (GetTickCount() % 2000) - 1000;
cTimeLeft = (cTimeout *= cMultiplier) + cFuzz;
cLoop++;
fSend = TRUE;
} else
fSend = FALSE;
} while (cLoop < cMaxLoop);
DEBUGMSG(ZONE_SEND, (TEXT("-SendDhcpPkt: pDhcp %X pPkt %X Ret: %d\r\n"),
pDhcp, pPkt, Status));
CTEGetLock(&pDhcp->Lock, 0);
return Status;
} // SendDhcpPkt()
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