#include "dhcp.h"
#include "dhcps.h"
#include "tcpip.h"
//static struct dhcp_server_state dhcp_server_state_machine;
static uint8_t dhcp_server_state_machine = DHCP_SERVER_STATE_IDLE;
/* recorded the client MAC addr(default sudo mac) */
//static uint8_t dhcps_record_first_client_mac[6] = {0xff,0xff,0xff,0xff,0xff,0xff};
/* recorded transaction ID (default sudo id)*/
static uint8_t dhcp_recorded_xid[4] = {0xff, 0xff, 0xff, 0xff};
/* UDP Protocol Control Block(PCB) */
static struct udp_pcb *dhcps_pcb;
static struct ip_addr dhcps_send_broadcast_address;
static struct ip_addr dhcps_local_address;
static struct ip_addr dhcps_local_mask;
static struct ip_addr dhcps_local_gateway;
static struct ip_addr dhcps_network_id;
static struct ip_addr dhcps_subnet_broadcast;
static struct ip_addr dhcps_allocated_client_address;
uint8_t dhcps_ip4addr_pool_start, dhcps_ip4addr_pool_end;
#if 0
static struct ip_addr dhcps_owned_first_ip;
static struct ip_addr dhcps_owned_last_ip;
static uint8_t dhcps_num_of_available_ips;
#endif
static struct dhcps_msg *dhcp_message_repository;
static int dhcp_message_total_options_lenth;
/* allocated IP range */
static struct table ip_table;
#define check_bit_ip_in_table(a) (ip_table.ip_range[(uint8_t)a >> 5] & (1 << ((uint8_t)a & ((1 << 5) - 1))))
#define set_bit_ip_in_table(a) (ip_table.ip_range[(uint8_t)a >> 5] |= (1 << ((uint8_t)a & ((1 << 5) - 1))))
static struct ip_addr client_request_ip;
static uint8_t dhcp_client_ethernet_address[16];
static uint8_t bound_client_ethernet_address[16];
static xSemaphoreHandle dhcps_ip_table_semaphore;
static struct netif * dhcps_netif = NULL;
/**
* @brief latch the specific ip in the ip table.
* @param d the specific index
* @retval None.
*/
#if (!IS_USE_FIXED_IP)
static void mark_ip_in_table(uint8_t d)
{
xSemaphoreTake(dhcps_ip_table_semaphore, portMAX_DELAY);
set_bit_ip_in_table(d);
xSemaphoreGive(dhcps_ip_table_semaphore);
}
/**
* @brief get one usable ip from the ip table of dhcp server.
* @param: None
* @retval the usable index which represent the ip4_addr(ip) of allocated ip addr.
*/
static uint8_t search_next_ip(void)
{
uint8_t count;
xSemaphoreTake(dhcps_ip_table_semaphore, portMAX_DELAY);
for(count = dhcps_ip4addr_pool_start; count <= dhcps_ip4addr_pool_end; count++) {
if(check_bit_ip_in_table(count) == 0) {
xSemaphoreGive(dhcps_ip_table_semaphore);
return count;
}
}
xSemaphoreGive(dhcps_ip_table_semaphore);
return 0;
}
#endif
/**
* @brief fill in the option field with message type of a dhcp message.
* @param msg_option_base_addr: the addr be filled start.
* message_type: the type code you want to fill in
* @retval the start addr of the next dhcp option.
*/
static uint8_t *add_msg_type(uint8_t *msg_option_base_addr, uint8_t message_type)
{
uint8_t *option_start;
msg_option_base_addr[0] = DHCP_OPTION_CODE_MSG_TYPE;
msg_option_base_addr[1] = DHCP_OPTION_LENGTH_ONE;
msg_option_base_addr[2] = message_type;
option_start = msg_option_base_addr + 3;
if (DHCP_MESSAGE_TYPE_NAK == message_type)
*option_start++ = DHCP_OPTION_CODE_END;
return option_start;
}
static uint8_t *fill_one_option_content(uint8_t *option_base_addr,
uint8_t option_code, uint8_t option_length, void *copy_info)
{
uint8_t *option_data_base_address;
uint8_t *next_option_start_address = NULL;
option_base_addr[0] = option_code;
option_base_addr[1] = option_length;
option_data_base_address = option_base_addr + 2;
switch (option_length) {
case DHCP_OPTION_LENGTH_FOUR:
memcpy(option_data_base_address, copy_info, DHCP_OPTION_LENGTH_FOUR);
next_option_start_address = option_data_base_address + 4;
break;
case DHCP_OPTION_LENGTH_TWO:
memcpy(option_data_base_address, copy_info, DHCP_OPTION_LENGTH_TWO);
next_option_start_address = option_data_base_address + 2;
break;
case DHCP_OPTION_LENGTH_ONE:
memcpy(option_data_base_address, copy_info, DHCP_OPTION_LENGTH_ONE);
next_option_start_address = option_data_base_address + 1;
break;
}
return next_option_start_address;
}
/**
* @brief fill in the needed content of the dhcp offer message.
* @param optptr the addr which the tail of dhcp magic field.
* @retval the addr represent to add the end of option.
*/
static void add_offer_options(uint8_t *option_start_address)
{
uint8_t *temp_option_addr;
/* add DHCP options 1.
The subnet mask option specifies the client's subnet mask */
temp_option_addr = fill_one_option_content(option_start_address,
DHCP_OPTION_CODE_SUBNET_MASK, DHCP_OPTION_LENGTH_FOUR,
(void *)&dhcps_local_mask);
/* add DHCP options 3 (i.e router(gateway)). The time server option
specifies a list of RFC 868 [6] time servers available to the client. */
temp_option_addr = fill_one_option_content(temp_option_addr,
DHCP_OPTION_CODE_ROUTER, DHCP_OPTION_LENGTH_FOUR,
(void *)&dhcps_local_address);
/* add DHCP options 6 (i.e DNS).
The option specifies a list of DNS servers available to the client. */
temp_option_addr = fill_one_option_content(temp_option_addr,
DHCP_OPTION_CODE_DNS_SERVER, DHCP_OPTION_LENGTH_FOUR,
(void *)&dhcps_local_address);
/* add DHCP options 51.
This option is used to request a lease time for the IP address. */
temp_option_addr = fill_one_option_content(temp_option_addr,
DHCP_OPTION_CODE_LEASE_TIME, DHCP_OPTION_LENGTH_FOUR,
(void *)&dhcp_option_lease_time_one_day);
/* add DHCP options 54.
The identifier is the IP address of the selected server. */
temp_option_addr = fill_one_option_content(temp_option_addr,
DHCP_OPTION_CODE_SERVER_ID, DHCP_OPTION_LENGTH_FOUR,
(void *)&dhcps_local_address);
/* add DHCP options 28.
This option specifies the broadcast address in use on client's subnet.*/
temp_option_addr = fill_one_option_content(temp_option_addr,
DHCP_OPTION_CODE_BROADCAST_ADDRESS, DHCP_OPTION_LENGTH_FOUR,
(void *)&dhcps_subnet_broadcast);
/* add DHCP options 26.
This option specifies the Maximum transmission unit to use */
temp_option_addr = fill_one_option_content(temp_option_addr,
DHCP_OPTION_CODE_INTERFACE_MTU, DHCP_OPTION_LENGTH_TWO,
(void *) &dhcp_option_interface_mtu);
/* add DHCP options 31.
This option specifies whether or not the client should solicit routers */
temp_option_addr = fill_one_option_content(temp_option_addr,
DHCP_OPTION_CODE_PERFORM_ROUTER_DISCOVERY, DHCP_OPTION_LENGTH_ONE,
NULL);
#if LWIP_NETIF_HOSTNAME
/* add DHCP options 12 HostName */
const char *p = dhcps_netif->hostname;
uint8_t len;
if(p && (len = strlen(p)) != 0) {
*temp_option_addr++ = DHCP_OPTION_HOSTNAME;
*temp_option_addr++ = len;
while(len--) {
*temp_option_addr++ = *p++;
}
}
#endif
*temp_option_addr = DHCP_OPTION_CODE_END;
}
/**
* @brief fill in common content of a dhcp message.
* @param m the pointer which point to the dhcp message store in.
* @retval None.
*/
static void dhcps_initialize_message(struct dhcps_msg *dhcp_message_repository, struct ip_addr yiaddr)
{
dhcp_message_repository->op = DHCP_MESSAGE_OP_REPLY;
dhcp_message_repository->htype = DHCP_MESSAGE_HTYPE;
dhcp_message_repository->hlen = DHCP_MESSAGE_HLEN;
dhcp_message_repository->hops = 0;
memcpy((char *)dhcp_recorded_xid, (char *) dhcp_message_repository->xid,
sizeof(dhcp_message_repository->xid));
dhcp_message_repository->secs = 0;
dhcp_message_repository->flags = htons(BOOTP_BROADCAST);
memcpy((char *)dhcp_message_repository->yiaddr,
(char *)&yiaddr,
sizeof(dhcp_message_repository->yiaddr));
memset((char *)dhcp_message_repository->ciaddr, 0,
sizeof(dhcp_message_repository->ciaddr));
memset((char *)dhcp_message_repository->siaddr, 0,
sizeof(dhcp_message_repository->siaddr));
memset((char *)dhcp_message_repository->giaddr, 0,
sizeof(dhcp_message_repository->giaddr));
memcpy((char *)dhcp_message_repository->chaddr, &dhcp_client_ethernet_address,
sizeof(dhcp_message_repository->chaddr));
memset((char *)dhcp_message_repository->sname, 0,
sizeof(dhcp_message_repository->sname));
memset((char *)dhcp_message_repository->file, 0,
sizeof(dhcp_message_repository->file));
memset((char *)dhcp_message_repository->options, 0,
dhcp_message_total_options_lenth);
memcpy((char *)dhcp_message_repository->options, (char *)dhcp_magic_cookie,
sizeof(dhcp_magic_cookie));
}
/**
* @brief init and fill in the needed content of dhcp offer message.
* @param packet_buffer packet buffer for UDP.
* @retval None.
*/
static void dhcps_send_offer(struct pbuf *packet_buffer)
{
uint8_t temp_ip = 0;
dhcp_message_repository = (struct dhcps_msg *)packet_buffer->payload;
#if (!IS_USE_FIXED_IP)
if ((ip4_addr4(&dhcps_allocated_client_address) != 0) &&
(memcmp((void *)&dhcps_allocated_client_address, (void *)&client_request_ip, 4) == 0) &&
(memcmp((void *)&bound_client_ethernet_address, (void *)&dhcp_client_ethernet_address, 16) == 0)) {
temp_ip = (uint8_t) ip4_addr4(&client_request_ip);
} else if ((ip4_addr1(&client_request_ip) == ip4_addr1(&dhcps_network_id)) &&
(ip4_addr2(&client_request_ip) == ip4_addr2(&dhcps_network_id)) &&
(ip4_addr3(&client_request_ip) == ip4_addr3(&dhcps_network_id))) {
uint8_t request_ip4 = (uint8_t) ip4_addr4(&client_request_ip);
if ((request_ip4 != 0)
&& check_bit_ip_in_table(request_ip4) == 0) {
temp_ip = request_ip4;
}
}
/* create new client ip */
if(temp_ip == 0) temp_ip = search_next_ip();
#if (debug_dhcps)
printf(" temp_ip = %d\n",temp_ip);
#endif
if (temp_ip == 0) {
#if 0
memset(&ip_table, 0, sizeof(struct table));
mark_ip_in_table((uint8_t)ip4_addr4(&dhcps_local_address));
printf("reset ip table!");
#endif
printf("No useable ip!");
}
IP4_ADDR(&dhcps_allocated_client_address, (ip4_addr1(&dhcps_network_id)),
ip4_addr2(&dhcps_network_id), ip4_addr3(&dhcps_network_id), temp_ip);
memcpy(bound_client_ethernet_address, dhcp_client_ethernet_address, sizeof(bound_client_ethernet_address));
#endif
dhcps_initialize_message(dhcp_message_repository, dhcps_allocated_client_address);
add_offer_options(add_msg_type(&dhcp_message_repository->options[4],
DHCP_MESSAGE_TYPE_OFFER));
udp_sendto_if(dhcps_pcb, packet_buffer,
&dhcps_send_broadcast_address, DHCP_CLIENT_PORT, dhcps_netif);
}
/**
* @brief init and fill in the needed content of dhcp nak message.
* @param packet buffer packet buffer for UDP.
* @retval None.
*/
static void dhcps_send_nak(struct pbuf *packet_buffer)
{
struct ip_addr zero_address;
IP4_ADDR(&zero_address, 0, 0, 0, 0);
dhcp_message_repository = (struct dhcps_msg *)packet_buffer->payload;
dhcps_initialize_message(dhcp_message_repository, zero_address);
add_msg_type(&dhcp_message_repository->options[4], DHCP_MESSAGE_TYPE_NAK);
udp_sendto_if(dhcps_pcb, packet_buffer,
&dhcps_send_broadcast_address, DHCP_CLIENT_PORT, dhcps_netif);
}
/**
* @brief init and fill in the needed content of dhcp ack message.
* @param packet buffer packet buffer for UDP.
* @retval None.
*/
static void dhcps_send_ack(struct pbuf *packet_buffer)
{
dhcp_message_repository = (struct dhcps_msg *)packet_buffer->payload;
dhcps_initialize_message(dhcp_message_repository, dhcps_allocated_client_address);
add_offer_options(add_msg_type(&dhcp_message_repository->options[4],
DHCP_MESSAGE_TYPE_ACK));
udp_sendto_if(dhcps_pcb, packet_buffer,
&dhcps_send_broadcast_address, DHCP_CLIENT_PORT, dhcps_netif);
}
/**
* @brief according by the input message type to reflect the correspond state.
* @param option_message_type the input server state
* @retval the server state which already transfer to.
*/
uint8_t dhcps_handle_state_machine_change(uint8_t option_message_type)
{
switch (option_message_type) {
case DHCP_MESSAGE_TYPE_DECLINE:
dhcp_server_state_machine = DHCP_SERVER_STATE_IDLE;
break;
case DHCP_MESSAGE_TYPE_DISCOVER:
if (dhcp_server_state_machine == DHCP_SERVER_STATE_IDLE) {
dhcp_server_state_machine = DHCP_SERVER_STATE_OFFER;
}
break;
case DHCP_MESSAGE_TYPE_REQUEST:
#if (!IS_USE_FIXED_IP)
if (dhcp_server_state_machine == DHCP_SERVER_STATE_OFFER) {
if (ip4_addr4(&dhcps_allocated_client_address) != 0) {
if (memcmp((void *)&dhcps_allocated_client_address, (void *)&client_request_ip, 4) == 0) {
dhcp_server_state_machine = DHCP_SERVER_STATE_ACK;
} else {
dhcp_server_state_machine = DHCP_SERVER_STATE_NAK;
}
} else {
dhcp_server_state_machine = DHCP_SERVER_STATE_NAK;
}
} else if (dhcp_server_state_machine == DHCP_SERVER_STATE_IDLE) {
if ((ip4_addr4(&dhcps_allocated_client_address) != 0) &&
(memcmp((void *)&dhcps_allocated_client_address, (void *)&client_request_ip, 4) == 0) &&
(memcmp((void *)&bound_client_ethernet_address, (void *)&dhcp_client_ethernet_address, 16) == 0)) {
dhcp_server_state_machine = DHCP_SERVER_STATE_ACK;
} else if ((ip4_addr1(&client_request_ip) == ip4_addr1(&dhcps_network_id)) &&
(ip4_addr2(&client_request_ip) == ip4_addr2(&dhcps_network_id)) &&
(ip4_addr3(&client_request_ip) == ip4_addr3(&dhcps_network_id))) {
uint8_t request_ip4 = (uint8_t) ip4_addr4(&client_request_ip);
if ((request_ip4 != 0)
&& check_bit_ip_in_table(request_ip4) == 0) {
IP4_ADDR(&dhcps_allocated_client_address, (ip4_addr1(&dhcps_network_id)),
ip4_addr2(&dhcps_network_id), ip4_addr3(&dhcps_network_id), request_ip4);
memcpy(bound_client_ethernet_address, dhcp_client_ethernet_address, sizeof(bound_client_ethernet_address));
dhcp_server_state_machine = DHCP_SERVER_STATE_ACK;
} else {
dhcp_server_state_machine = DHCP_SERVER_STATE_NAK;
}
} else {
dhcp_server_state_machine = DHCP_SERVER_STATE_NAK;
}
} else {
dhcp_server_state_machine = DHCP_SERVER_STATE_NAK;
}
#else
if (!(dhcp_server_state_machine == DHCP_SERVER_STATE_ACK ||
dhcp_server_state_machine == DHCP_SERVER_STATE_NAK)) {
dhcp_server_state_machine = DHCP_SERVER_STATE_NAK;
}
#endif
break;
case DHCP_MESSAGE_TYPE_RELEASE:
dhcp_server_state_machine = DHCP_SERVER_STATE_IDLE;
break;
}
return dhcp_server_state_machine;
}
/**
* @brief parse the dhcp message option part.
* @param optptr: the addr of the first option field.
* len: the total length of all option fields.
* @retval dhcp server state.
*/
static uint8_t dhcps_handle_msg_options(uint8_t *option_start, int16_t total_option_length)
{
int16_t option_message_type = 0;
uint8_t *option_end = option_start + total_option_length;
//dhcp_server_state_machine = DHCP_SERVER_STATE_IDLE;
/* begin process the dhcp option info */
while (option_start < option_end) {
switch ((uint8_t)*option_start) {
case DHCP_OPTION_CODE_MSG_TYPE:
option_message_type = *(option_start + 2); // 2 => code(1)+lenth(1)
break;
case DHCP_OPTION_CODE_REQUEST_IP_ADDRESS :
#if IS_USE_FIXED_IP
if (memcmp((char *)&dhcps_allocated_client_address,
(char *)option_start + 2, 4) == 0)
dhcp_server_state_machine = DHCP_SERVER_STATE_ACK;
else
dhcp_server_state_machine = DHCP_SERVER_STATE_NAK;
#else
memcpy((char *)&client_request_ip, (char *)option_start + 2, 4);
#endif
break;
}
// calculate the options offset to get next option's base addr
option_start += option_start[1] + 2; // optptr[1]: length value + (code(1)+ Len(1))
}
return dhcps_handle_state_machine_change(option_message_type);
}
/**
* @brief get message from buffer then check whether it is dhcp related or not.
* if yes , parse it more to undersatnd the client's request.
* @param same as recv callback function definition
* @retval if message is dhcp related then return dhcp server state,
* otherwise return 0
*/
static uint8_t dhcps_check_msg_and_handle_options(struct pbuf *packet_buffer)
{
int dhcp_message_option_offset;
dhcp_message_repository = (struct dhcps_msg *)packet_buffer->payload;
memcpy(dhcp_client_ethernet_address, dhcp_message_repository->chaddr, sizeof(dhcp_client_ethernet_address));
dhcp_message_option_offset = ((int)dhcp_message_repository->options
- (int)packet_buffer->payload);
dhcp_message_total_options_lenth = (packet_buffer->len
- dhcp_message_option_offset);
/* check the magic number,if correct parse the content of options */
if (memcmp((char *)dhcp_message_repository->options,
(char *)dhcp_magic_cookie, sizeof(dhcp_magic_cookie)) == 0) {
return dhcps_handle_msg_options(&dhcp_message_repository->options[4],
(dhcp_message_total_options_lenth - 4));
}
return 0;
}
/**
* @brief handle imcoming dhcp message and response message to client
* @param same as recv callback function definition
* @retval None
*/
static void dhcps_receive_udp_packet_handler(void *arg, struct udp_pcb *udp_pcb,
struct pbuf *udp_packet_buffer, struct ip_addr *sender_addr, uint16_t sender_port)
{
int16_t total_length_of_packet_buffer;
struct pbuf *merged_packet_buffer = NULL;
dhcp_message_repository = (struct dhcps_msg *)udp_packet_buffer->payload;
if (udp_packet_buffer == NULL) {
printf("Error! System doesn't allocate any buffer\n");
return;
}
if (sender_port == DHCP_CLIENT_PORT) {
total_length_of_packet_buffer = udp_packet_buffer->tot_len;
if (udp_packet_buffer->next != NULL) {
merged_packet_buffer = pbuf_coalesce(udp_packet_buffer,
PBUF_TRANSPORT);
if (merged_packet_buffer->tot_len !=
total_length_of_packet_buffer) {
pbuf_free(udp_packet_buffer);
return;
}
}
switch (dhcps_check_msg_and_handle_options(udp_packet_buffer)) {
case DHCP_SERVER_STATE_OFFER:
dhcps_send_offer(udp_packet_buffer);
break;
case DHCP_SERVER_STATE_ACK:
dhcps_send_ack(udp_packet_buffer);
#if (!IS_USE_FIXED_IP)
mark_ip_in_table((uint8_t)ip4_addr4(&dhcps_allocated_client_address));
#endif
dhcp_server_state_machine = DHCP_SERVER_STATE_IDLE;
break;
case DHCP_SERVER_STATE_NAK:
dhcps_send_nak(udp_packet_buffer);
dhcp_server_state_machine = DHCP_SERVER_STATE_IDLE;
break;
case DHCP_OPTION_CODE_END:
break;
}
}
/* free the UDP connection, so we can accept new clients */
udp_disconnect(udp_pcb);
/* Free the packet buffer */
if (merged_packet_buffer != NULL)
pbuf_free(merged_packet_buffer);
else
pbuf_free(udp_packet_buffer);
}
void dhcps_set_addr_pool(int addr_pool_set, struct ip_addr * addr_pool_start, struct ip_addr *addr_pool_end)
{
dhcps_ip4addr_pool_start = ip4_addr4(addr_pool_start);
dhcps_ip4addr_pool_end = ip4_addr4(addr_pool_end);
}
/**
* @brief Initialize dhcp server.
* @param None.
* @retval None.
* Note, for now,we assume the server latch ip 192.168.1.1 and support dynamic
* or fixed IP allocation.
*/
void dhcps_init(struct netif * pnetif)
{
// printf("dhcps_init,wlan:%c\n\r",pnetif->name[1]);
dhcps_netif = pnetif;
dhcps_deinit();
dhcps_pcb = udp_new();
if (dhcps_pcb == NULL) {
printf("Error! upd_new error\n");
return;
}
IP4_ADDR(&dhcps_send_broadcast_address, 255, 255, 255, 255);
memset(&ip_table, 0, sizeof(struct table));
if((dhcps_ip4addr_pool_end | dhcps_ip4addr_pool_start) == 0) {
dhcps_ip4addr_pool_start = 2;
dhcps_ip4addr_pool_end = 255;
}
/* get net info from net interface */
memcpy(&dhcps_local_address, &pnetif->ip_addr,
sizeof(struct ip_addr));
memcpy(&dhcps_local_mask, &pnetif->netmask,
sizeof(struct ip_addr));
memcpy(&dhcps_local_gateway, &pnetif->gw,
sizeof(struct ip_addr));
/* calculate the usable network ip range */
dhcps_network_id.addr = ((pnetif->ip_addr.addr) &
(pnetif->netmask.addr));
dhcps_subnet_broadcast.addr = ((dhcps_network_id.addr |
~(pnetif->netmask.addr)));
#if 0
dhcps_owned_first_ip.addr = htonl((ntohl(dhcps_network_id.addr) + 1));
dhcps_owned_last_ip.addr = htonl(ntohl(dhcps_subnet_broadcast.addr) - 1);
dhcps_num_of_available_ips = ((ntohl(dhcps_owned_last_ip.addr)
- ntohl(dhcps_owned_first_ip.addr)) + 1);
#endif
#if IS_USE_FIXED_IP
IP4_ADDR(&dhcps_allocated_client_address, ip4_addr1(&dhcps_local_address)
, ip4_addr2(&dhcps_local_address), ip4_addr3(&dhcps_local_address),
(ip4_addr4(&dhcps_local_address)) + 1 );
#else
dhcps_ip_table_semaphore = xSemaphoreCreateMutex();
memset(&dhcps_allocated_client_address, 0, sizeof(struct ip_addr));
memset(bound_client_ethernet_address, 0, sizeof(bound_client_ethernet_address));
mark_ip_in_table((uint8_t)ip4_addr4(&dhcps_local_address));
mark_ip_in_table((uint8_t)ip4_addr4(&dhcps_local_gateway));
#if 0
for (i = 1; i < ip4_addr4(&dhcps_local_address); i++) {
mark_ip_in_table(i);
}
#endif
#endif
udp_bind(dhcps_pcb, IP_ADDR_ANY, DHCP_SERVER_PORT);
udp_recv(dhcps_pcb, dhcps_receive_udp_packet_handler, NULL);
}
void dhcps_deinit(void)
{
if (dhcps_pcb != NULL) {
udp_remove(dhcps_pcb);
dhcps_pcb = NULL;
}
if (dhcps_ip_table_semaphore != NULL) {
vSemaphoreDelete(dhcps_ip_table_semaphore);
dhcps_ip_table_semaphore = NULL;
}
}