static gboolean listener_event(GIOChannel *channel, GIOCondition condition,
gpointer user_data)
{
GDHCPServer *dhcp_server = user_data;
struct dhcp_packet packet;
struct dhcp_lease *lease;
uint32_t requested_nip = 0;
uint8_t type, *server_id_option, *request_ip_option, *host_name;
int re;
GDHCPOptionType option_type;
char *option_value;
if (condition & (G_IO_NVAL | G_IO_ERR | G_IO_HUP)) {
dhcp_server->listener_watch = 0;
return FALSE;
}
re = dhcp_recv_l3_packet(&packet, dhcp_server->listener_sockfd);
if (re < 0)
return TRUE;
type = check_packet_type(&packet);
if (type == 0)
return TRUE;
server_id_option = dhcp_get_option(&packet, DHCP_SERVER_ID);
if (server_id_option) {
uint32_t server_nid = get_be32(server_id_option);
if (server_nid != dhcp_server->server_nip)
return TRUE;
}
request_ip_option = dhcp_get_option(&packet, DHCP_REQUESTED_IP);
if (request_ip_option)
requested_nip = get_be32(request_ip_option);
lease = find_lease_by_mac(dhcp_server, packet.chaddr);
switch (type) {
case DHCPDISCOVER:
debug(dhcp_server, "Received DISCOVER");
send_offer(dhcp_server, &packet, lease, requested_nip);
break;
case DHCPREQUEST:
debug(dhcp_server, "Received REQUEST NIP %d",
requested_nip);
if (requested_nip == 0) {
requested_nip = packet.ciaddr;
if (requested_nip == 0)
break;
}
if (lease && requested_nip == lease->lease_nip) {
debug(dhcp_server, "Sending ACK");
host_name =
dhcp_get_option(&packet,
DHCP_HOST_NAME);
option_type =
dhcp_get_code_type(DHCP_HOST_NAME);
option_value =
malloc_option_value_string(host_name,
option_type);
send_ACK(dhcp_server, &packet,
lease->lease_nip);
if (dhcp_server->save_ack_lease_func)
dhcp_server->save_ack_lease_func(
option_value,
lease->lease_mac,
lease->lease_nip);
g_free(option_value);
break;
}
if (server_id_option || !lease) {
debug(dhcp_server, "Sending NAK");
send_NAK(dhcp_server, &packet);
}
break;
case DHCPDECLINE:
debug(dhcp_server, "Received DECLINE");
if (!server_id_option)
break;
if (!request_ip_option)
break;
if (!lease)
break;
if (requested_nip == lease->lease_nip)
remove_lease(dhcp_server, lease);
break;
case DHCPRELEASE:
debug(dhcp_server, "Received RELEASE");
if (!server_id_option)
break;
if (!lease)
break;
if (packet.ciaddr == lease->lease_nip)
lease_set_expire(dhcp_server, lease,
time(NULL));
break;
case DHCPINFORM:
debug(dhcp_server, "Received INFORM");
send_inform(dhcp_server, &packet);
break;
}
return TRUE;
}
void handle_dhcp(struct server_conf *conf, pcap_t *p, struct pktbuf *inpkt) {
unsigned char tag, len;
int i, j;
int msgtype;
union ip_address ip;
unsigned char buffer[512];
guint32 lease;
unsigned char *options = inpkt->dhcp_packet->options;
unsigned char *srcmac = inpkt->eth_header->h_source;
struct client_conf *client;
#if DEBUG
fprintf(stderr, "Optionslen: %d\n", inpkt->optlen);
#endif
if (inpkt->optlen < 6) return;
#if DEBUG
fprintf(stderr, "%d.%d.%d.%d\n", options[0], options[1], options[2], options[3]);
#endif
// check the magic cookie
if (!(options[0] == 99 && options[1] == 130
&& options[2]== 83 && options[3] == 99)) {
return;
}
i = 4;
while (1) {
CHKOPTLEN(2);
tag = options[i++];
if (tag == 0) continue;
if (tag == 255) goto END;
len = options[i++];
CHKOPTLEN(len);
switch (tag) {
case 1:
// Subnet Mask
if (len != 4) {
fprintf(stderr, "Malformed len in subnet mask tag: Should be 4 but is %d\n", len);
return;
}
ip.a[0] = options[i++]; ip.a[1] = options[i++]; ip.a[2] = options[i++]; ip.a[3] = options[i++];
printf("Subnet Mask: %d.%d.%d.%d\n", ip.a[0], ip.a[1], ip.a[2], ip.a[3]);
break;
case 3:
// Default Gateway
if (len < 4) {
fprintf(stderr, "Malformed len in router tag: Should 4 or greater but is %d\n", len);
return;
}
if (len % 4 != 0) {
fprintf(stderr, "Malformed len in router tag: Should be a multiple of 4 but is %d\n", len);
return;
}
len /= 4;
for (j = 0; j < len; j++) {
ip.a[0] = options[i++];
ip.a[1] = options[i++];
ip.a[2] = options[i++];
ip.a[3] = options[i++];
#if DEBUG
printf("Router %d: %d.%d.%d.%d\n", j + 1, ip.a[0], ip.a[1], ip.a[2], ip.a[3]);
#endif
}
break;
case 6:
// DNS Servers
if (len < 4) {
fprintf(stderr, "Malformed len in DNS tag: Should 4 or greater but is %d\n", len);
return;
}
if (len % 4 != 0) {
fprintf(stderr, "Malformed len in DNS tag: Should be a multiple of 4 but is %d\n", len);
return;
}
len /= 4;
for (j = 0; j < len; j++) {
ip.a[0] = options[i++];
ip.a[1] = options[i++];
ip.a[2] = options[i++];
ip.a[3] = options[i++];
#if DEBUG
printf("DNS Server %d: %d.%d.%d.%d\n", j + 1, ip.a[0], ip.a[1], ip.a[2], ip.a[3]);
#endif
}
break;
break;
case 12:
// Host Name Option
memcpy(buffer, &options[i], len);
buffer[len] = '\0';
#if DEBUG
printf("Hostname: %s\n", buffer);
#endif
i += len;
break;
case 50:
// Requested IP
if (len != 4) {
fprintf(stderr, "Malformed len in requested IP tag: Should be 4 but is %d\n", len);
return;
}
ip.a[0] = options[i++];
ip.a[1] = options[i++];
ip.a[2] = options[i++];
ip.a[3] = options[i++];
printf("Requested IP: %d.%d.%d.%d\n", ip.a[0], ip.a[1], ip.a[2], ip.a[3]);
break;
break;
case 51:
// Lease Time in Seconds
lease = *((guint32*) &options[i]);
lease = ntohl(lease);
printf("Lease: %ld\n", (long) lease);
i += len;
break;
case 53:
// DHCP Message Type
msgtype = options[i++];
printf("MSG TYPE: %d\n", msgtype);
printf("MSG TYPE: %s\n", msgtypes[msgtype]);
break;
case 54:
// Server Identifier
if (len != 4) {
fprintf(stderr, "Malformed len in server identifier tag: Should be 4 but is %d\n", len);
return;
}
ip.a[0] = options[i++];
ip.a[1] = options[i++];
ip.a[2] = options[i++];
ip.a[3] = options[i++];
printf("Server Identifier: %d.%d.%d.%d\n", ip.a[0], ip.a[1], ip.a[2], ip.a[3]);
break;
case 55:
printf("DHCP options: ");
for (j = 0; j < len; j++) {
if (j != 0) printf(", ");
printf("%d", options[i++]);
}
printf("\n");
break;
default:
fprintf(stderr, "ERROR: Unknown DHCP Option Tag: %d\n", tag);
// skip over this tag
i += len;
}
}
END:
// we serve only MACs we know
fprintf(stderr, "Lookup of MAC %x:%x:%x:%x:%x:%x in VLAN %d\n",
srcmac[0], srcmac[1], srcmac[2], srcmac[3], srcmac[4], srcmac[5], inpkt->vlan);
client = lookup_client(conf, inpkt->vlan, srcmac);
if (client == NULL) return;
fprintf(stderr, "Lookup successful\n");
if (msgtype == DHCPDISCOVER) {
send_offer(p, inpkt, client);
} else if (msgtype == DHCPREQUEST) {
send_ack(p, inpkt, client);
}
}
static gboolean listener_event(GIOChannel *channel, GIOCondition condition,
gpointer user_data)
{
GDHCPServer *dhcp_server = user_data;
struct dhcp_packet packet;
struct dhcp_lease *lease;
uint32_t requested_nip = 0;
uint8_t type, *server_id_option, *request_ip_option;
int re;
if (condition & (G_IO_NVAL | G_IO_ERR | G_IO_HUP)) {
dhcp_server->listener_watch = 0;
return FALSE;
}
re = dhcp_recv_l3_packet(&packet, dhcp_server->listener_sockfd);
if (re < 0)
return TRUE;
type = check_packet_type(&packet);
if (type == 0)
return TRUE;
server_id_option = dhcp_get_option(&packet, DHCP_SERVER_ID);
if (server_id_option) {
uint32_t server_nid = dhcp_get_unaligned(
(uint32_t *) server_id_option);
if (server_nid != dhcp_server->server_nip)
return TRUE;
}
request_ip_option = dhcp_get_option(&packet, DHCP_REQUESTED_IP);
if (request_ip_option)
requested_nip = dhcp_get_unaligned(
(uint32_t *) request_ip_option);
lease = find_lease_by_mac(dhcp_server, packet.chaddr);
switch (type) {
case DHCPDISCOVER:
debug(dhcp_server, "Received DISCOVER");
send_offer(dhcp_server, &packet, lease, requested_nip);
break;
case DHCPREQUEST:
debug(dhcp_server, "Received REQUEST NIP %d",
requested_nip);
if (requested_nip == 0) {
requested_nip = packet.ciaddr;
if (requested_nip == 0)
break;
}
if (lease && requested_nip == lease->lease_nip) {
debug(dhcp_server, "Sending ACK");
send_ACK(dhcp_server, &packet,
lease->lease_nip);
break;
}
if (server_id_option || lease == NULL) {
debug(dhcp_server, "Sending NAK");
send_NAK(dhcp_server, &packet);
}
break;
case DHCPDECLINE:
debug(dhcp_server, "Received DECLINE");
if (server_id_option == NULL)
break;
if (request_ip_option == NULL)
break;
if (lease == NULL)
break;
if (requested_nip == lease->lease_nip)
remove_lease(dhcp_server, lease);
break;
case DHCPRELEASE:
debug(dhcp_server, "Received RELEASE");
if (server_id_option == NULL)
break;
if (lease == NULL)
break;
if (packet.ciaddr == lease->lease_nip)
lease_set_expire(dhcp_server, lease,
time(NULL));
break;
case DHCPINFORM:
debug(dhcp_server, "Received INFORM");
send_inform(dhcp_server, &packet);
break;
}
return TRUE;
}
static void ICACHE_FLASH_ATTR handle_dhcp(void *arg,
struct udp_pcb *pcb,
struct pbuf *p,
struct ip_addr *addr,
uint16_t port)
{
struct dhcps_msg *pmsg_dhcps = NULL;
sint16_t tlen = 0;
u16_t i = 0;
u16_t dhcps_msg_cnt = 0;
u8_t *p_dhcps_msg = NULL;
u8_t *data = NULL;
#if DHCPS_DEBUG
os_printf("dhcps: handle_dhcp-> receive a packet\n");
#endif
if (p==NULL) return;
pmsg_dhcps = (struct dhcps_msg *)os_zalloc(sizeof(struct dhcps_msg));
if (NULL == pmsg_dhcps){
pbuf_free(p);
return;
}
p_dhcps_msg = (u8_t *)pmsg_dhcps;
tlen = p->tot_len;
data = p->payload;
#if DHCPS_DEBUG
os_printf("dhcps: handle_dhcp-> p->tot_len = %d\n", tlen);
os_printf("dhcps: handle_dhcp-> p->len = %d\n", p->len);
#endif
for(i=0; i<p->len; i++){
p_dhcps_msg[dhcps_msg_cnt++] = data[i];
#if DHCPS_DEBUG
os_printf("%02x ",data[i]);
if((i+1)%16 == 0){
os_printf("\n");
}
#endif
}
if(p->next != NULL) {
#if DHCPS_DEBUG
os_printf("dhcps: handle_dhcp-> p->next != NULL\n");
os_printf("dhcps: handle_dhcp-> p->next->tot_len = %d\n",p->next->tot_len);
os_printf("dhcps: handle_dhcp-> p->next->len = %d\n",p->next->len);
#endif
data = p->next->payload;
for(i=0; i<p->next->len; i++){
p_dhcps_msg[dhcps_msg_cnt++] = data[i];
#if DHCPS_DEBUG
os_printf("%02x ",data[i]);
if((i+1)%16 == 0){
os_printf("\n");
}
#endif
}
}
/*
* DHCP �ͻ���������Ϣ����
*/
#if DHCPS_DEBUG
os_printf("dhcps: handle_dhcp-> parse_msg(p)\n");
#endif
switch(parse_msg(pmsg_dhcps, tlen - 240)) {
case DHCPS_STATE_OFFER://1
#if DHCPS_DEBUG
os_printf("dhcps: handle_dhcp-> DHCPD_STATE_OFFER\n");
#endif
send_offer(pmsg_dhcps);
break;
case DHCPS_STATE_ACK://3
#if DHCPS_DEBUG
os_printf("dhcps: handle_dhcp-> DHCPD_STATE_ACK\n");
#endif
send_ack(pmsg_dhcps);
break;
case DHCPS_STATE_NAK://4
#if DHCPS_DEBUG
os_printf("dhcps: handle_dhcp-> DHCPD_STATE_NAK\n");
#endif
send_nak(pmsg_dhcps);
break;
default :
break;
}
#if DHCPS_DEBUG
os_printf("dhcps: handle_dhcp-> pbuf_free(p)\n");
#endif
pbuf_free(p);
os_free(pmsg_dhcps);
pmsg_dhcps = NULL;
}
