int ProcessDHCPMessage (struct dhcp_packet *pDhcpPkt, int *pSize)
{
unsigned char *p=NULL;
struct LL_IP *pCurIP=NULL, *pProposedIP=NULL; // Thanks Sam Leitch !
int Ark, nDhcpType = 0;
struct in_addr sRequestedAddr;
DWORD sStaticIP;
if (IsDHCP (*pDhcpPkt))
{
// search DHCP message type
p = DHCPSearchOptionsField (pDhcpPkt->options, DHO_DHCP_MESSAGE_TYPE, NULL);
if (p!=NULL) nDhcpType = *p;
}
if (pDhcpPkt->yiaddr.s_addr!=INADDR_ANY && pDhcpPkt->yiaddr.s_addr!=INADDR_NONE )
return FALSE ; // address already assigned
// the tab has one undef raw
for (Ark=0 ; Ark<SizeOfTab(tDHCPType)-1 && nDhcpType!=tDHCPType[Ark].nType ; Ark++) ;
LOG (5, "Rcvd %s Msg for IP %s, Mac %s",
tDHCPType[Ark].sType,
inet_ntoa (pDhcpPkt->ciaddr),
haddrtoa(pDhcpPkt->chaddr, pDhcpPkt->hlen,':'));
// if (sParamDHCP.nPoolSize==0) return FALSE; // no allocation pool --> listen only
switch (nDhcpType)
{
case 0 : // BootP
if(sParamDHCP.nIgnoreBootp)
{
LOG (5, "Ignoring Bootp request");
break;
}
case DHCPDISCOVER :
sStaticIP = DHCP_StaticAssignation (pDhcpPkt);
if (sStaticIP != INADDR_NONE)
{
LOG (0, "%s: statically assigned to address %s",
haddrtoa(pDhcpPkt->chaddr, pDhcpPkt->hlen,':'),
inet_ntoa (* (struct in_addr *) & sStaticIP) );
pDhcpPkt->yiaddr.s_addr = sStaticIP;
}
else
{
p = DHCPSearchOptionsField (pDhcpPkt->options, DHO_DHCP_REQUESTED_ADDRESS, NULL);
if (p!=NULL)
{
pDhcpPkt->ciaddr = * (struct in_addr *) p;
LOG (5, "Client requested address %s", inet_ntoa (pDhcpPkt->ciaddr));
}
pProposedIP = DHCP_IPAllocate (nDhcpType, & pDhcpPkt->ciaddr, pDhcpPkt->chaddr, pDhcpPkt->hlen);
if (pProposedIP == NULL)
{
LOG (1, "no more address or address previously allocated by another server");
return FALSE;
}
pDhcpPkt->yiaddr.s_addr = pProposedIP->dwIP.s_addr;
LOG (2, "%s: proposed address %s", IsDHCP(*pDhcpPkt) ? "DHCP" : "BOOTP", inet_ntoa (pProposedIP->dwIP) );
//If this is a bootp, there is no other response from the client.
//Since we don't want leases expiring (or being mistaken for unAcked DHCP offers),
//set renewed to a distant time
if(nDhcpType == 0 && sStaticIP == INADDR_NONE) // patched by Rolf Offermanns
ForceRenewTime(pProposedIP, 0x66666666); // fixed by Sam Leitch
} // dynamically assigned address
// populate the packet to be returned
pDhcpPkt->op = BOOTREPLY;
// translate $IP$ and $MAC$ from boot file name
TranslateExp (sParamDHCP.szBootFile, pDhcpPkt->file, pDhcpPkt->yiaddr, pDhcpPkt->chaddr);
*pSize = DHCPOptionsReply (pDhcpPkt, DHCPOFFER);
break ;
//NJW Changed how requests are handled to mimic linux -- requests are responded to even if we didn't originally allocate, but only if the requested address is in our pool range
case DHCPREQUEST :
{BOOL bSERVER = FALSE; // TRUE if Tftpd32 has assigned this address
// Static Allocation ?
// search field REQUEST ADDR in options
sStaticIP = DHCP_StaticAssignation (pDhcpPkt);
if (sStaticIP != INADDR_NONE)
{
// populate the packet to be returned
pDhcpPkt->op = BOOTREPLY;
pDhcpPkt->yiaddr.s_addr = sStaticIP;
// translate $IP$ and $MAC$ from boot file name
TranslateExp (sParamDHCP.szBootFile, pDhcpPkt->file, pDhcpPkt->yiaddr, pDhcpPkt->chaddr);
*pSize = DHCPOptionsReply (pDhcpPkt, DHCPACK);
break;
}
// has tftpd32 dinamically assigned this address
pCurIP = DHCPSearchByMacAddress (pDhcpPkt->chaddr, pDhcpPkt->hlen);
if (pCurIP==NULL) return FALSE; // not attributed by Tftpd32 --> do not answer
// search field REQUEST ADDR in options
// if specified should fit database
p = DHCPSearchOptionsField (pDhcpPkt->options, DHO_DHCP_REQUESTED_ADDRESS, NULL);
if (p!=NULL)
{
pDhcpPkt->ciaddr = * (struct in_addr *) p;
}
if(AddrFitsPool(&pDhcpPkt->ciaddr))
{
//Look up the address, if it's not found, or the owner is this macaddr,
//or the lease was expired, allow the serving.
BOOL wasexpired = FALSE;
pProposedIP = DHCPSearchByIP(&pDhcpPkt->ciaddr, &wasexpired);
bSERVER = !pProposedIP || wasexpired || (0 == memcmp(pProposedIP->sMacAddr, pDhcpPkt->chaddr, 6));
}
if (bSERVER)
{
pProposedIP = DHCP_IPAllocate (nDhcpType, & pDhcpPkt->ciaddr, pDhcpPkt->chaddr, pDhcpPkt->hlen);
if (pProposedIP == NULL)
{
LOG (1, "no more addresses or address previously allocated by another server");
return FALSE;
}
if (pProposedIP->tAllocated==0) SetAllocTime(pProposedIP);
SetRenewTime(pProposedIP);
LOG (5, "Previously allocated address %s acked", inet_ntoa (pProposedIP->dwIP));
// populate the packet to be returned
pDhcpPkt->op = BOOTREPLY;
pDhcpPkt->yiaddr.s_addr = pProposedIP->dwIP.s_addr;
TranslateExp (sParamDHCP.szBootFile, pDhcpPkt->file, pDhcpPkt->yiaddr, pDhcpPkt->chaddr);
*pSize = DHCPOptionsReply (pDhcpPkt, DHCPACK);
}
else
{
LOG (5, "Client requested address %s which was not allocated by tftpd32 and is either outside our pool or is used by someone else",
inet_ntoa (pDhcpPkt->ciaddr) );
return FALSE ; // do not answer
}
} // Block for bSERVER declaration
break;
case DHCPDECLINE :
// search current item and its precedent
pCurIP = DHCPSearchByMacAddress (pDhcpPkt->chaddr, pDhcpPkt->hlen);
if (pCurIP!=NULL)
{
p = DHCPSearchOptionsField (pDhcpPkt->options, DHO_DHCP_REQUESTED_ADDRESS, NULL);
if (p!=NULL)
{
sRequestedAddr.s_addr = * (DWORD *) p;
if ( pCurIP->dwIP.s_addr==sRequestedAddr.s_addr)
{
DHCPDestroyItem (pCurIP);
LOG (5, "item destroyed");
}
}
}
//The decline is sent when an address is already in use. Do an ARP and
//add a lease for the in-use address
{
ULONG mac[2];
ULONG maclen = 6;
// search field REQUEST ADDR in options
// if specified should fit database
p = DHCPSearchOptionsField (pDhcpPkt->options, DHO_DHCP_REQUESTED_ADDRESS, NULL);
if (p!=NULL)
{
pDhcpPkt->ciaddr = * (struct in_addr *) p;
}
if(NO_ERROR == SendARP(pDhcpPkt->ciaddr.s_addr, 0, mac, &maclen))
{
pProposedIP = DHCP_IPAllocate (nDhcpType, & pDhcpPkt->ciaddr, (unsigned char*)mac, maclen);
if (pProposedIP)
{
if (pProposedIP->tAllocated==0) SetAllocTime(pProposedIP);
ForceRenewTime(pProposedIP, 0x66666666); //Give a bootp lease, since the device may not do dhcp
LOG (5, "Added lease for existing address %s", inet_ntoa (pProposedIP->dwIP));
}
}
}
break;
case DHCPRELEASE :
// do not destroy the item but mark it free
pCurIP = DHCPSearchByMacAddress (pDhcpPkt->chaddr, pDhcpPkt->hlen);
if (pCurIP!=NULL) // then mac address found in table
{
ZeroAllocTime(pCurIP);
ZeroRenewTime(pCurIP);
LOG (5, "item %s released", haddrtoa(pDhcpPkt->chaddr, pDhcpPkt->hlen,':') );
}
break;
} // switch type
DHCPScan();
// answer only to BootP, Request or discover msg
return (nDhcpType==0 || nDhcpType==DHCPDISCOVER || nDhcpType==DHCPREQUEST);
} // ProcessDHCPMessage
static int ProcessMsg (SOCKET s, const struct S_ConsoleMsg *pmsg)
{
struct LL_TftpInfo *pTftp;
int uServices;
LogToMonitor ("TFTPd console receive msg %d\n", pmsg->type);
switch (pmsg->type)
{
case C_CONS_KILL_TRF :
LOG (1, "transfer %d must be killed", pmsg->u.kill.dwTransferId);
for ( pTftp=pTftpFirst ;
pTftp!=NULL && pTftp->tm.dwTransferId != pmsg->u.kill.dwTransferId ;
pTftp = pTftp->next );
if (pTftp != NULL) { nak (pTftp, ECANCELLED); pTftp->st.ret_code=TFTP_TRF_STOPPED; }
break;
case C_TFTP_TERMINATE :
LogToMonitor ("terminating TFTP service\n");
tThreads[TH_TFTP].gRunning = FALSE;
WakeUpThread (TH_TFTP);
break;
case C_DHCP_TERMINATE :
LogToMonitor ("terminating DHCP service\n");
tThreads[TH_DHCP].gRunning = FALSE;
// wake up DHCP thread
WakeUpThread (TH_DHCP);
break;
case C_TERMINATE :
LogToMonitor ("stopping services\n");
TerminateWorkerThreads (FALSE); // keep management threads
break;
case C_SUSPEND :
LogToMonitor ("suspending services\n");
TerminateWorkerThreads (TRUE); // keep management threads
break;
case C_START :
LogToMonitor ("starting services\n");
StartMultiWorkerThreads (TRUE);
break;
case C_DHCP_RRQ_SETTINGS :
LogToMonitor ("sending DHCP settings\n");
SendMsg (s, C_DHCP_RPLY_SETTINGS, & sParamDHCP, sizeof sParamDHCP);
break;
case C_TFTP_RRQ_SETTINGS :
LogToMonitor ("sending TFTP settings\n");
SendMsg (s, C_TFTP_RPLY_SETTINGS, & sSettings, sizeof sSettings);
break;
case C_DHCP_WRQ_SETTINGS :
LogToMonitor ("storing new DHCP settings\n");
DHCPSaveConfig ( & pmsg->u.dhcp_settings );
break;
case C_TFTP_WRQ_SETTINGS :
LogToMonitor ("storing new TFTP settings\n");
{static struct S_RestartTable sRestart;
sRestart.newservices = pmsg->u.tftp_settings.uServices;
sRestart.oldservices = sSettings.uServices;
sRestart.flapservices = 0;
if ( sSettings.Port != pmsg->u.tftp_settings.Port
|| lstrcmp (sSettings.szTftpLocalIP, pmsg->u.tftp_settings.szTftpLocalIP )!=0 )
sRestart.flapservices |= TFTPD32_TFTP_SERVER;
// restart syslog if its settings log has changed
if ( sSettings.uServices & TFTPD32_SYSLOG_SERVER
&& ( sSettings.bSyslogPipe != pmsg->u.tftp_settings.bSyslogPipe
|| strcmp(sSettings.szSyslogFile,pmsg->u.tftp_settings.szSyslogFile)!= 0 )
)
sRestart.flapservices |= TFTPD32_SYSLOG_SERVER;
sSettings = pmsg->u.tftp_settings;
if ( IsValidDirectory ( pmsg->u.tftp_settings.szBaseDirectory ) )
lstrcpyn ( sSettings.szWorkingDirectory,
pmsg->u.tftp_settings.szBaseDirectory,
sizeof sSettings.szWorkingDirectory );
_beginthread ( Tftpd32UpdateServices, 0, (void *) & sRestart );
Tftpd32SaveSettings ();
}
break;
case C_TFTP_RESTORE_DEFAULT_SETTINGS :
LogToMonitor ("restore default settings\n");
Tftpd32DestroySettings ();
break;
case C_TFTP_CHG_WORKING_DIR :
LogToMonitor ("changing working directory to <%s>\n", pmsg->u.working_dir);
if ( IsValidDirectory ( pmsg->u.working_dir ) )
lstrcpyn ( sSettings.szWorkingDirectory,
pmsg->u.working_dir,
sizeof sSettings.szWorkingDirectory );
break;
case C_RRQ_WORKING_DIR :
LogToMonitor ("sending working directory <%s>\n", sSettings.szWorkingDirectory);
SendMsg (s, C_REPLY_WORKING_DIR,
sSettings.szWorkingDirectory,
1 + lstrlen (sSettings.szWorkingDirectory) );
break;
case C_DELETE_ASSIGNATION :
LogToMonitor ("deleting DHCP entry %X\n", pmsg->u.del_lease.ip);
{ struct in_addr addr;
BOOL dummy;
addr.s_addr = pmsg->u.del_lease.ip;
DHCPDestroyItem ( DHCPSearchByIP ( & addr, &dummy ) );
}
break;
case C_RRQ_GET_SERVICES :
LogToMonitor ("sending running services\n");
uServices = GetRunningThreads ();
SendMsg (s,
C_REPLY_GET_SERVICES,
& uServices,
sizeof uServices );
break;
case C_RRQ_GET_INTERFACES :
LogToMonitor ("sending IP interfaces");
AnswerIPList ();
break;
case C_RRQ_DIRECTORY_CONTENT :
LogToMonitor ("sending Directory content");
SendDirectoryContent ();
break;
case C_TFTP_GET_FULL_STAT :
LogToMonitor ("sending Directory content");
ConsoleTftpGetStatistics ();
break;
default :
LogToMonitor ("Service received unknown message %d\n", pmsg->type);
break;
}
return 1;
} // ReadMsg
struct LL_IP *DHCP_IPAllocate2(struct in_addr *pPreviousAddr, const unsigned char *pMac, int nMacLen)
{
time_t tNow;
int Ark;
struct LL_IP *pCurIP /*, *pOldestIP*/;
#define TWO_MINUTES 120
//If true, the client has requested an IP address that we should try to honor
int useprev = (pPreviousAddr->s_addr != INADDR_ANY) && (AddrFitsPool(pPreviousAddr));
// search for the previously allocated mac address
if (nMacLen>=6) // Ethernet Mac address
{
// search if mac the mac address is already known
pCurIP = DHCPSearchByMacAddress (pMac, nMacLen);
if(pCurIP)
{
//We found the previous MAC record. If the address requested is invalid, use
//the address in the record. If it is valid, erase the record, since we should
//give the requested address
if(!useprev || (pPreviousAddr->s_addr == pCurIP->dwIP.s_addr))
{
LOG (12, "Reply with previously allocated : %s", inet_ntoa (pCurIP->dwIP));
SetAllocTime(pCurIP);
return pCurIP;
}
else //Remove the old address, and continue with the allocation logic
{
//Destroying the item takes care of the macaddr table as well.
DHCPDestroyItem (pCurIP);
pCurIP = NULL;
}
} // mac address found
} // mac address not valid
// search if requested address can be granted
if(useprev)
{
// is the address already allocated but not renewed (or expired)
BOOL wasexpired=FALSE;
pCurIP = DHCPSearchByIP (pPreviousAddr, &wasexpired);
if (pCurIP!=NULL)
{
//Only allocate if it's to the same address, or the lease expired,
//otherwise reset for the real allocation
if(wasexpired || (0 == memcmp(pCurIP->sMacAddr, pMac, nMacLen)))
{
LOG (5, "Request for %s granted", inet_ntoa (pCurIP->dwIP));
pCurIP = DHCPReallocItem (pCurIP, pPreviousAddr->s_addr, pMac, nMacLen);
return pCurIP ;
}
else
pCurIP = NULL;
}
else //Address not allocated before, just grant it
{
pCurIP = DHCPReallocItem (NULL, pPreviousAddr->s_addr, pMac, nMacLen);
LOG (12, "Reply with requested address : %s", inet_ntoa (pCurIP->dwIP));
return pCurIP;
} //
} // Requested address asked
// A new IP address should be allocated :
// First check if the pool is large enough in order to allocate a new address
if (sParamDHCP.nPoolSize>0 && nAllocatedIP < sParamDHCP.nPoolSize)
{
// search for an "hole" in the struct or take last elem + 1
// if an item was allocated and the first item is the first in pool
//Don't allocate ip addresses ending in 0 or 255
if (nAllocatedIP>0 && tFirstIP[0]->dwIP.s_addr == sParamDHCP.dwAddr.s_addr)
{
for ( Ark=1 ;
Ark<nAllocatedIP
&& ntohl (tFirstIP[Ark]->dwIP.s_addr) == AddrInc(tFirstIP[Ark-1]->dwIP);
Ark ++ );
pCurIP = DHCPReallocItem (NULL, htonl (AddrInc(tFirstIP[Ark-1]->dwIP)), pMac, nMacLen);
}
else pCurIP = DHCPReallocItem (NULL, sParamDHCP.dwAddr.s_addr, pMac, nMacLen);
// New address : ntohl (tFirstIP[Ark]->dwIP.s_addr) + 1
// it is OK if Ark has reach nAllocatedIP
LOG (12, "Reply with new : %s", inet_ntoa (pCurIP->dwIP));
return pCurIP;
} // new allocation
// no free address, have to reuse an "old" one
// try addresses which have not been acknowledged (tAllocated+2 minutes),
// or that have expired
//
time (&tNow);
for (Ark=0 ; Ark<nAllocatedIP; Ark++)
{
pCurIP = tFirstIP[Ark];
if ( pCurIP->tAllocated+TWO_MINUTES < tNow
&& ((pCurIP->tRenewed==0) || (tNow > pCurIP->tRenewed + (sParamDHCP.nLease * 60))))
{
pCurIP = DHCPReallocItem (pCurIP, pCurIP->dwIP.s_addr, pMac, nMacLen);
LOG (12, "Reply with reuse : %s", inet_ntoa (pCurIP->dwIP));
return pCurIP;
}
} // reuse an unacknowledged address
/* Since we are replacing holes, unacked, and expired addresses, all addresses are currently used
// search for the oldest one (use tAllocated and tRenewed)
for (Ark=0, pOldestIP=NULL ; Ark<nAllocatedIP; Ark++)
{
pCurIP = tFirstIP[Ark];
if ( pCurIP->tRenewed!=0
&& pCurIP->tRenewed < (unsigned) (pOldestIP==NULL ? 0xFFFFFFFF : pOldestIP->tRenewed )
&& PingApi (&pCurIP->dwIP, DHCP_PINGTIMEOUT, NULL)==PINGAPI_TIMEOUT
&& PingApi (&pCurIP->dwIP, DHCP_PINGTIMEOUT, NULL)==PINGAPI_TIMEOUT
&& PingApi (&pCurIP->dwIP, DHCP_PINGTIMEOUT, NULL)==PINGAPI_TIMEOUT
) pOldestIP=pCurIP;
} // search for oldest item in pOldestIP
if (pOldestIP != NULL)
{
pCurIP = DHCPReallocItem (pOldestIP, pOldestIP->dwIP.s_addr, pMac, nMacLen);
LOG (12, "Reply with reuse : %s", inet_ntoa (pCurIP->dwIP));
return pCurIP; // can be NULL
}
*/
return NULL;
} // DHCP_IPAllocate2
