int check_and_ack(struct dhcpMessage* packet, uint32_t ip)
{
uint32_t static_ip = 0;
/* There is an Static IP for this guy, whether it is requested or not */
if ((static_ip = getIpByMac(server_config.static_leases, packet->chaddr)) != 0)
{
msglogd(LOG_INFO, LOGTYPE_DHCP, "DHCPS:REQUEST ip %x, static ip %x", ip, static_ip);
return sendACK(packet, static_ip);
}
/* requested ip is reserved by a static lease -- if it is himself, situation above match */
if (reservedIp(server_config.static_leases, ip))
{
msglogd(LOG_INFO, LOGTYPE_DHCP, "DHCPS:REQUEST ip %x is reserved as a static ip", ip);
return sendNAK(packet);
}
/* if some one reserve it */
if ( ip != packet->ciaddr && check_ip(packet, ip) )
{
msglogd(LOG_INFO, LOGTYPE_DHCP, "DHCPS:REQUEST ip %x already reserved by someone", ip);
return sendNAK(packet);
}
if (ntohl(ip) < ntohl(server_config.start) || ntohl(ip) > ntohl(server_config.end))
{
msglogd(LOG_INFO, LOGTYPE_DHCP, "DHCPS:REQUEST ip %x is not in the address pool", ip);
return sendNAK(packet);
}
return sendACK(packet, ip);
}
/* find an assignable address, it check_expired is true, we check all the expired leases as well.
* Maybe this should try expired leases by age... */
uint32_t find_address(int check_expired)
{
uint32_t addr, ret;
struct dhcpOfferedAddr *lease = NULL;
addr = ntohl(server_config.start); /* addr is in host order here */
for (;addr <= ntohl(server_config.end); addr++) {
/* ie, 192.168.55.0 */
if (!(addr & 0xFF)) continue;
/* ie, 192.168.55.255 */
if ((addr & 0xFF) == 0xFF) continue;
/* Only do if it isn't an assigned as a static lease */
if (!reservedIp(server_config.static_leases, htonl(addr))) {
/* lease is not taken */
ret = htonl(addr);
lease = find_lease_by_yiaddr(ret);
/* no lease or it expired and we are checking for expired leases */
if ( (!lease || (check_expired && lease_expired(lease)))
&& /* and it isn't on the network */ !check_ip(ret)
) {
return ret;
break;
}
}
}
return 0;
}
/* true if a lease has expired */
int lease_expired(struct dhcpOfferedAddr *lease)
{
#ifdef STATIC_LEASE
if (reservedIp(server_config.static_leases, lease->yiaddr))
return 0;
#endif
return (lease->expires < (unsigned long) time(0));
}
/* send a DHCP OFFER to a DHCP DISCOVER */
int sendOffer(struct dhcpMessage *oldpacket)
{
struct dhcpMessage packet;
struct dhcpOfferedAddr *lease = NULL;
u_int32_t req_align, lease_time_align = server_config.lease;
char *req, *lease_time;
struct option_set *curr;
char * l_vdfoption[OPTION_LEN];
int l_ilen = 0;
struct in_addr addr;
#ifdef VDF_OPTION
//add for option125
char VIinfo[VENDOR_IDENTIFYING_INFO_LEN];
unsigned char StrOption121[OPTION121_LEN];
#endif
/*start A36D02806, s60000658, 20060906*/
struct option_set *opt = NULL;
u_int32_t router_ip = 0;
if(NULL != (opt = find_option(server_config.options, DHCP_ROUTER)))
{
router_ip = *(u_int32_t*)(opt->data + 2);
}
/*end A36D02806, s60000658, 20060906*/
init_packet(&packet, oldpacket, DHCPOFFER);
#ifdef SUPPORT_MACMATCHIP
if ( !ismacmatch(oldpacket->chaddr) )
{
packet.yiaddr = find_matchip(oldpacket->chaddr);
}
else
#endif
/* the client is in our lease/offered table */
if ((lease = find_lease_by_chaddr(oldpacket->chaddr))) {
/*Start of Mod by y67514:time（0）取的系统时间会受SNTP影响，导致定时器混乱*/
if (!lease_expired(lease))
lease_time_align = lease->expires - getSysUpTime();
/*End of Mod by y67514:time（0）取的系统时间会受SNTP影响，导致定时器混乱*/
packet.yiaddr = lease->yiaddr;
/* Or the client has a requested ip */
} else if ((req = get_option(oldpacket, DHCP_REQUESTED_IP)) &&
/* Don't look here (ugly hackish thing to do) */
memcpy(&req_align, req, 4) &&
/* and the ip is in the lease range */
ntohl(req_align) >= ntohl(server_config.start) &&
ntohl(req_align) <= ntohl(server_config.end) &&
#ifdef VDF_RESERVED
//and the ip is not the reserved ip
reservedIp(req_align)&&
#endif
#ifdef SUPPORT_MACMATCHIP
isipmatch(req_align) &&
#endif
/* and its not already taken/offered */
((!(lease = find_lease_by_yiaddr(req_align)) ||
/* or its taken, but expired */
lease_expired(lease)))) {
#ifdef SUPPORT_DHCP_FRAG
int tmpNum = 1, i =0;
if(1 == inmaster)
{
for(i = 0; i < 5; i++)
{
if(ntohl(req_align) >= ntohl(ipPool[i].start) &&
ntohl(req_align) <= ntohl(ipPool[i].end))
{
tmpNum = 0;
break;
}
}
}
#endif
/*start of DHCP 网关会分配自己的维护IP porting by w44771 20060505*/
/*packet.yiaddr = req_align; */
if((req_align != server_config.server)
#ifdef SUPPORT_DHCP_FRAG
&& (req_align != router_ip) && (1 == tmpNum))/*A36D02806, s60000658, 20060906*/
#else
&& (req_align != router_ip))/*A36D02806, s60000658, 20060906*/
#endif
{
packet.yiaddr = req_align;
}
else
{
#ifdef SUPPORT_DHCP_FRAG
if(1 == inmaster)
/* find an assignable address, it check_expired is true, we check all the expired leases as well.
* Maybe this should try expired leases by age... */
u_int32_t find_address(int check_expired)
{
u_int32_t addr, ret;
struct dhcpOfferedAddr *lease = NULL;
addr = ntohl(server_config.start); /* addr is in host order here */
for (;addr <= ntohl(server_config.end); addr++) {
#if 1
/* Network IP and BroadcastIP
ie. netmask 255.255.255.0, server ip 192.168.55.1
can't lease 192.168.55.0 or 192.168.55.255
*/
if(addr==(server_config.netmask & server_config.server))
continue;
if(addr==((~(server_config.netmask))|(server_config.server)))
continue;
#else
/* ie, 192.168.55.0 */
if (!(addr & 0xFF)) continue;
/* ie, 192.168.55.255 */
if ((addr & 0xFF) == 0xFF) continue;
#endif
/* not lease server ip */
if(addr == server_config.server) continue;
#ifdef STATIC_LEASE
/* Only do if it isn't an assigned as a static lease */
if(!reservedIp(server_config.static_leases, htonl(addr)))
#endif
{
/* lease is not taken */
ret = htonl(addr);
if ((!(lease = find_lease_by_yiaddr(ret)) ||
/* or it expired and we are checking for expired leases */
( (check_expired == 1) && lease_expired(lease))) &&
/* and it isn't on the network */
!check_ip(ret)) {
return ret;
}
else if(check_expired == 2) //some one leases this ip and this ip is not expired.
{
int arpping_time = 0;
int ret_arpping = 0;
//printf("\r\n Any one use this ip[%x]?",ret);
for(arpping_time = 0; arpping_time<3; arpping_time++)
{
char ret_hwaddr[6];
if (arpping(ret, server_config.server, server_config.arp, server_config.interface, ret_hwaddr) == 0)
{
ret_arpping = 1;
break;
}
}
// But this ip is not alive in network. we release this ip
if ( ret_arpping == 1)
{
//printf(" YES.__[%s-%u]\r\n",__FILE__,__LINE__);
}
else
{
//printf(" NO.__[%s-%u]\r\n",__FILE__,__LINE__);
return ret;
}
}
}
}
return 0;
}