ahhh

2 files changed, 126 insertions, 165 deletions

diff --git a/libdhcp/dhcp.c b/libdhcp/dhcp.c
index bba61b9..2fc7724 100644
--- a/libdhcp/dhcp.c
+++ b/libdhcp/dhcp.c
@@ -96,7 +96,7 @@ struct dhcp_msg {
 	uint8_t                 hlen;       /* length of ->chaddr (`sizeof(struct net_eth_addr)`) */
 	uint8_t                 hops;
 
-	uint32be_t              xid;        /* `global_xid`; this increase one every DHCP transaction */
+	uint32be_t              xid;        /* transaction ID */
 
 	uint16be_t              secs;
 	uint16be_t              flags;      /* DHCP_FLAG_{x} */
@@ -250,8 +250,6 @@ int8_t              dhcp_state       = STATE_DHCP_INIT; /* DHCP state */
 int8_t              dhcp_retry_count = 0;
 volatile uint32_t   dhcp_tick_1s     = 0;               /* unit 1 second */
 uint32_t            dhcp_tick_next   = DHCP_WAIT_TIME ;
-uint32_t            global_xid;                         /* Any number */
-struct dhcp_msg    *pDHCPMSG;                           /* Buffer pointer for DHCP processing */
 char                global_hostname[64];
 struct net_eth_addr global_eth_addr;                    /* DHCP Client MAC address. */
 
@@ -268,26 +266,30 @@ static inline size_t str_encode(void *dst, char *str) {
 }
 
 /* make the common DHCP message */
-static void dhcp_msg_init(struct dhcp_msg *msg, size_t *optlen) {
+static inline void dhcp_msg_init(struct dhcp_msg *msg, size_t *optlen,
+                                 struct net_eth_addr self_eth_addr,
+                                 uint16_t flags, uint32_t xid) {
 	size_t tmp;
 
 	assert(msg);
 	assert(optlen);
 
+	*msg = (struct dhcp_msg){0};
+
 	msg->op     = DHCP_OP_BOOTREQUEST;
 	msg->htype  = DHCP_HTYPE_ETHERNET;
-	msg->hlen   = sizeof(global_eth_addr);
+	msg->hlen   = sizeof(self_eth_addr);
 	msg->hops   = CONFIG_DHCP_HOPS;
-	msg->xid    = uint32be_marshal(global_xid);
+	msg->xid    = uint32be_marshal(xid);
 	msg->secs   = uint16be_marshal(CONFIG_DHCP_SECS);
-	msg->flags  = uint16be_marshal(DHCP_FLAG_BROADCAST);
+	msg->flags  = uint16be_marshal(flags);
 	msg->ciaddr = (struct net_ip4_addr){0};
 	msg->yiaddr = (struct net_ip4_addr){0};
 	msg->siaddr = (struct net_ip4_addr){0};
 	msg->siaddr = (struct net_ip4_addr){0};
 	msg->giaddr = (struct net_ip4_addr){0};
 
-	tmp = mem_encode(msg->chaddr, global_eth_addr);
+	tmp = mem_encode(msg->chaddr, self_eth_addr);
 	memset(&msg->chaddr[tmp], 0, sizeof(msg->chaddr)-tmp);
 
 	memset(msg->sname, 0, sizeof(msg->sname));
@@ -301,57 +303,60 @@ static void dhcp_msg_init(struct dhcp_msg *msg, size_t *optlen) {
 }
 
 static void dhcp_send_DISCOVER(implements_net_packet_conn *sock) {
+	struct dhcp_msg msg;
 	size_t k;
 
-	dhcp_msg_init(pDHCPMSG, &k);
+	dhcp_msg_init(&msg, &k, DHCP_FLAG_BROADCAST);
 	DHCP_SIP = (struct net_ip4_addr){0};
 	DHCP_REAL_SIP = (struct net_ip4_addr){0};
 
 	/* Message type.  */
-	pDHCPMSG->options[k++] = DHCP_OPT_DHCP_MSG_TYPE;
-	pDHCPMSG->options[k++] = 1;
-	pDHCPMSG->options[k++] = DHCP_MSGTYP_DISCOVER;
+	msg->options[k++] = DHCP_OPT_DHCP_MSG_TYPE;
+	msg->options[k++] = 1;
+	msg->options[k++] = DHCP_MSGTYP_DISCOVER;
 
 	/* Our Client ID.  */
-	pDHCPMSG->options[k++] = DHCP_OPT_CLIENT_ID;
-	pDHCPMSG->options[k++] = 1+sizeof(global_eth_addr);
-	pDHCPMSG->options[k++] = DHCP_HTYPE_ETHERNET;
-	k += mem_encode(&pDHCPMSG->options[k], global_eth_addr);
+	msg->options[k++] = DHCP_OPT_CLIENT_ID;
+	msg->options[k++] = 1+sizeof(self_eth_addr);
+	msg->options[k++] = DHCP_HTYPE_ETHERNET;
+	k += mem_encode(&msg->options[k], self_eth_addr);
 
 	/* Our requested hostname.  */
-	pDHCPMSG->options[k++] = DHCP_OPT_HOSTNAME;
-	pDHCPMSG->options[k++] = strlen(global_hostname);
-	k += str_encode(&pDHCPMSG->options[k], global_hostname);
+	msg->options[k++] = DHCP_OPT_HOSTNAME;
+	msg->options[k++] = strlen(global_hostname);
+	k += str_encode(&msg->options[k], global_hostname);
 
 	/* Which parameters we want back.  */
-	pDHCPMSG->options[k++] = DHCP_OPT_PARAMETER_LIST;
-	pDHCPMSG->options[k++] = 6;
-	pDHCPMSG->options[k++] = DHCP_OPT_SUBNET_MASK;    /* 1 */
-	pDHCPMSG->options[k++] = DHCP_OPT_ROUTER;         /* 2 */
-	pDHCPMSG->options[k++] = DHCP_OPT_DOMAIN_SERVER;  /* 3 */
-	pDHCPMSG->options[k++] = DHCP_OPT_DOMAIN_NAME;    /* 4 */
-	pDHCPMSG->options[k++] = DHCP_OPT_RENEWAL_TIME;   /* 5 */
-	pDHCPMSG->options[k++] = DHCP_OPT_REBINDING_TIME; /* 6 */
+	msg->options[k++] = DHCP_OPT_PARAMETER_LIST;
+	msg->options[k++] = 6;
+	msg->options[k++] = DHCP_OPT_SUBNET_MASK;    /* 1 */
+	msg->options[k++] = DHCP_OPT_ROUTER;         /* 2 */
+	msg->options[k++] = DHCP_OPT_DOMAIN_SERVER;  /* 3 */
+	msg->options[k++] = DHCP_OPT_DOMAIN_NAME;    /* 4 */
+	msg->options[k++] = DHCP_OPT_RENEWAL_TIME;   /* 5 */
+	msg->options[k++] = DHCP_OPT_REBINDING_TIME; /* 6 */
 
 	/* End.  */
-	pDHCPMSG->options[k++] = DHCP_OPT_END;
+	msg->options[k++] = DHCP_OPT_END;
+	assert(k <= CONFIG_DHCP_OPT_SIZE);
 
+	/* Send. */
 	debugf("> Send DHCP_DISCOVER");
-	assert(k <= CONFIG_DHCP_OPT_SIZE);
-	VCALL(sock, sendto, pDHCPMSG, DHCP_MSG_BASE_SIZE + k, net_ip4_addr_broadcast, DHCP_PORT_SERVER);
+	VCALL(sock, sendto, msg, DHCP_MSG_BASE_SIZE + k, net_ip4_addr_broadcast, DHCP_PORT_SERVER);
 }
 
 static void dhcp_send_REQUEST(implements_net_packet_conn *sock) {
 	struct net_ip4_addr ip;
+	struct dhcp_msg msg;
 	size_t k;
 
-	dhcp_msg_init(pDHCPMSG, &k);
+	dhcp_msg_init(msg, &k,
+	              (dhcp_state != STATE_DHCP_LEASED && dhcp_state != STATE_DHCP_REREQUEST) ? DHCP_FLAG_BROADCAST : 0);
 
 	switch (dhcp_state) {
 	case STATE_DHCP_LEASED:
 	case STATE_DHCP_REREQUEST:
-		pDHCPMSG->flags = uint16be_marshal(0);
-		pDHCPMSG->ciaddr = global_lease.addr;
+		msg->ciaddr = global_lease.addr;
 		ip = DHCP_SIP;
 		break;
 	default:
@@ -359,59 +364,59 @@ static void dhcp_send_REQUEST(implements_net_packet_conn *sock) {
 	}
 
 	/* Message type.  */
-	pDHCPMSG->options[k++] = DHCP_OPT_DHCP_MSG_TYPE;
-	pDHCPMSG->options[k++] = 1;
-	pDHCPMSG->options[k++] = DHCP_MSGTYP_REQUEST;
+	msg->options[k++] = DHCP_OPT_DHCP_MSG_TYPE;
+	msg->options[k++] = 1;
+	msg->options[k++] = DHCP_MSGTYP_REQUEST;
 
 	/* Our Client ID.  */
-	pDHCPMSG->options[k++] = DHCP_OPT_CLIENT_ID;
-	pDHCPMSG->options[k++] = 1+sizeof(global_eth_addr);
-	pDHCPMSG->options[k++] = DHCP_HTYPE_ETHERNET;
-	k += mem_encode(&pDHCPMSG->options[k], global_eth_addr);
+	msg->options[k++] = DHCP_OPT_CLIENT_ID;
+	msg->options[k++] = 1+sizeof(self_eth_addr);
+	msg->options[k++] = DHCP_HTYPE_ETHERNET;
+	k += mem_encode(&msg->options[k], self_eth_addr);
 
 	switch (dhcp_state) {
 	case STATE_DHCP_LEASED:
 	case STATE_DHCP_REREQUEST:
 		/* Our current IP address.  */
-		pDHCPMSG->options[k++] = DHCP_OPT_ADDRESS_REQUEST;
-		pDHCPMSG->options[k++] = sizeof(global_lease.addr);
-		k += mem_encode(&pDHCPMSG->options[k], global_lease.addr);
+		msg->options[k++] = DHCP_OPT_ADDRESS_REQUEST;
+		msg->options[k++] = sizeof(global_lease.addr);
+		k += mem_encode(&msg->options[k], global_lease.addr);
 
 		/* The server we got it from.  */
-		pDHCPMSG->options[k++] = DHCP_OPT_DHCP_SERVER_ID;
-		pDHCPMSG->options[k++] = sizeof(DHCP_SIP);
-		k += mem_encode(&pDHCPMSG->options[k], DHCP_SIP);
+		msg->options[k++] = DHCP_OPT_DHCP_SERVER_ID;
+		msg->options[k++] = sizeof(DHCP_SIP);
+		k += mem_encode(&msg->options[k], DHCP_SIP);
 	}
 
 	/* Our requested hostname.  */
-	pDHCPMSG->options[k++] = DHCP_OPT_HOSTNAME;
-	pDHCPMSG->options[k++] = strlen(global_hostname);
-	k += str_encode(&pDHCPMSG->options[k], global_hostname);
+	msg->options[k++] = DHCP_OPT_HOSTNAME;
+	msg->options[k++] = strlen(global_hostname);
+	k += str_encode(&msg->options[k], global_hostname);
 
 	/* Which parameters we want back.  */
-	pDHCPMSG->options[k++] = DHCP_OPT_PARAMETER_LIST;
-	pDHCPMSG->options[k++] = 8;
-	pDHCPMSG->options[k++] = DHCP_OPT_SUBNET_MASK;      /* 1 */
-	pDHCPMSG->options[k++] = DHCP_OPT_ROUTER;           /* 2 */
-	pDHCPMSG->options[k++] = DHCP_OPT_DOMAIN_SERVER;    /* 3 */
-	pDHCPMSG->options[k++] = DHCP_OPT_DOMAIN_NAME;      /* 4 */
-	pDHCPMSG->options[k++] = DHCP_OPT_RENEWAL_TIME;     /* 5 */
-	pDHCPMSG->options[k++] = DHCP_OPT_REBINDING_TIME;   /* 6 */
-	pDHCPMSG->options[k++] = DHCP_OPT_ROUTER_DISCOVERY; /* 7 */
-	pDHCPMSG->options[k++] = DHCP_OPT_STATIC_ROUTE;     /* 8 */
+	msg->options[k++] = DHCP_OPT_PARAMETER_LIST;
+	msg->options[k++] = 8;
+	msg->options[k++] = DHCP_OPT_SUBNET_MASK;      /* 1 */
+	msg->options[k++] = DHCP_OPT_ROUTER;           /* 2 */
+	msg->options[k++] = DHCP_OPT_DOMAIN_SERVER;    /* 3 */
+	msg->options[k++] = DHCP_OPT_DOMAIN_NAME;      /* 4 */
+	msg->options[k++] = DHCP_OPT_RENEWAL_TIME;     /* 5 */
+	msg->options[k++] = DHCP_OPT_REBINDING_TIME;   /* 6 */
+	msg->options[k++] = DHCP_OPT_ROUTER_DISCOVERY; /* 7 */
+	msg->options[k++] = DHCP_OPT_STATIC_ROUTE;     /* 8 */
 
 	/* End.  */
-	pDHCPMSG->options[k++] = DHCP_OPT_END;
+	msg->options[k++] = DHCP_OPT_END;
+	assert(k <= CONFIG_DHCP_OPT_SIZE);
 
 	debugf("> Send DHCP_REQUEST");
-	assert(k <= CONFIG_DHCP_OPT_SIZE);
-	VCALL(sock, sendto, pDHCPMSG, DHCP_MSG_BASE_SIZE + k, ip, DHCP_PORT_SERVER);
+	VCALL(sock, sendto, msg, DHCP_MSG_BASE_SIZE + k, ip, DHCP_PORT_SERVER);
 }
 
 static void dhcp_send_DECLINE(implements_net_packet_conn *sock) {
 	size_t k;
 
-	dhcp_msg_init(pDHCPMSG, &k);
+	dhcp_msg_init(pDHCPMSG, &k, DHCP_FLAG_BROADCAST);
 	pDHCPMSG->flags = uint16be_marshal(0);
 
 	/* Option Request Param. */
@@ -421,10 +426,10 @@ static void dhcp_send_DECLINE(implements_net_packet_conn *sock) {
 
 	/* Our Client ID.  */
 	pDHCPMSG->options[k++] = DHCP_OPT_CLIENT_ID;
-	pDHCPMSG->options[k++] = 1+sizeof(global_eth_addr);
+	pDHCPMSG->options[k++] = 1+sizeof(self_eth_addr);
 	pDHCPMSG->options[k++] = DHCP_HTYPE_ETHERNET;
-	memcpy(&pDHCPMSG->options[k], global_eth_addr.octets, sizeof(global_eth_addr));
-	k += sizeof(global_eth_addr);
+	memcpy(&pDHCPMSG->options[k], self_eth_addr.octets, sizeof(self_eth_addr));
+	k += sizeof(self_eth_addr);
 
 	/* Our current IP address.  */
 	pDHCPMSG->options[k++] = DHCP_OPT_ADDRESS_REQUEST;
@@ -456,7 +461,7 @@ static int8_t dhcp_msg_parse(implements_net_packet_conn *sock) {
 		return 0;
 	}
 	/* Compare our MAC address.  */
-	if (memcmp(pDHCPMSG->chaddr, global_eth_addr.octets, sizeof(global_eth_addr))) {
+	if (memcmp(pDHCPMSG->chaddr, self_eth_addr.octets, sizeof(self_eth_addr))) {
 		debugf("Not my DHCP Message.  This message is ignored.");
 		return 0;
 	}
@@ -482,6 +487,7 @@ static int8_t dhcp_msg_parse(implements_net_packet_conn *sock) {
 			break;
 		default:
 			opt_len = pDHCPMSG->options[k++];
+			xhandle(opt_typ, opt_len, &pDHCPMSG->options[k]);
 		}
 		switch (opt_typ) {
 		case DHCP_OPT_DHCP_MSG_TYPE:
@@ -489,30 +495,6 @@ static int8_t dhcp_msg_parse(implements_net_packet_conn *sock) {
 				continue;
 			msg_type = pDHCPMSG->options[k];
 			break;
-		case DHCP_OPT_SUBNET_MASK:
-			if (opt_len != 4)
-				continue;
-			global_lease.subnet_mask.octets[0] = pDHCPMSG->options[k+0];
-			global_lease.subnet_mask.octets[1] = pDHCPMSG->options[k+1];
-			global_lease.subnet_mask.octets[2] = pDHCPMSG->options[k+2];
-			global_lease.subnet_mask.octets[3] = pDHCPMSG->options[k+3];
-			break;
-		case DHCP_OPT_ROUTER :
-			if (opt_len < 4)
-				continue;
-			global_lease.gateway.octets[0] = pDHCPMSG->options[k+0];
-			global_lease.gateway.octets[1] = pDHCPMSG->options[k+1];
-			global_lease.gateway.octets[2] = pDHCPMSG->options[k+2];
-			global_lease.gateway.octets[3] = pDHCPMSG->options[k+3];
-			break;
-		case DHCP_OPT_DOMAIN_SERVER :
-			if (opt_len < 4)
-				continue;
-			global_lease.dns.octets[0] = pDHCPMSG->options[k+0];
-			global_lease.dns.octets[1] = pDHCPMSG->options[k+1];
-			global_lease.dns.octets[2] = pDHCPMSG->options[k+2];
-			global_lease.dns.octets[3] = pDHCPMSG->options[k+3];
-			break;
 		case DHCP_OPT_ADDRESS_TIME:
 			if (opt_len != 4)
 				continue;
@@ -613,21 +595,35 @@ static int8_t dhcp_check_leasedIP(implements_net_packet_conn *sock) {
 	return 0;
 }
 
-uint8_t DHCP_run(struct w5500 *chip, uint8_t socknum, dhcp_callback_t cb) {
-	uint8_t  msg_type;
-	uint8_t  ret;
+COROUTINE DHCP_cr(struct w5500 *chip, uint8_t socknum,
+                  struct net_eth_addr self_eth_addr,
+                  char *self_hostname,
+                  dhcp_callback_t cb) {
+	uint32_t xid;
+	implements_net_packet_conn *sock;
+
+	xid = 0x12345678;
+	xid += self_eth_addr.octets[3];
+	xid += self_eth_addr.octets[4];
+	xid += self_eth_addr.octets[5];
+	xid += (self_eth_addr.octets[3] ^
+	        self_eth_addr.octets[4] ^
+	        self_eth_addr.octets[5]);
 
-	if (dhcp_state == STATE_DHCP_STOP)
-		return DHCP_RET_STOPPED;
+	dhcp_tick_1s = 0;
+	dhcp_tick_next = DHCP_WAIT_TIME;
+	dhcp_retry_count = 0;
+	dhcp_state = STATE_DHCP_INIT;
 
-	implements_net_packet_conn *sock = w5500_udp_conn(chip, socknum, DHCP_PORT_CLIENT);
+	sock = w5500_udp_conn(chip, socknum, DHCP_PORT_CLIENT);
 
-	ret = DHCP_RET_RUNNING;
-	msg_type = dhcp_msg_parse(sock);
+		ret = DHCP_RET_RUNNING;
+		msg_type = dhcp_msg_parse(sock);
 
-	switch ( dhcp_state ) {
+	for (;;) {
+		/* State transition diagram: https://datatracker.ietf.org/doc/html/rfc2131#page-35 */
+		switch (state) {
 	case STATE_DHCP_INIT:
-		global_lease.addr = net_ip4_addr_zero;
 		dhcp_send_DISCOVER(sock);
 		dhcp_state = STATE_DHCP_DISCOVER;
 		break;
@@ -675,7 +671,7 @@ uint8_t DHCP_run(struct w5500 *chip, uint8_t socknum, dhcp_callback_t cb) {
 			msg_type = 0;
 			OLD_allocated_ip = global_lease.addr;
 
-			global_xid++;
+			xid++;
 
 			dhcp_send_REQUEST(sock);
 
@@ -712,58 +708,3 @@ uint8_t DHCP_run(struct w5500 *chip, uint8_t socknum, dhcp_callback_t cb) {
 
 	return ret;
 }
-
-void DHCP_stop(implements_net_packet_conn *sock) {
-	VCALL(sock, close);
-	dhcp_state = STATE_DHCP_STOP;
-}
-
-void DHCP_init(void *buf) {
-	getSHAR(global_eth_addr);
-	if (memcmp(global_eth_addr.octets, ((struct net_eth_addr){0}).octets, sizeof(struct net_eth_addr)) == 0) {
-		/* assigning temporary mac address, you should be set
-		 * SHAR before call this function.  */
-		global_eth_addr.octets[0] = 0x00;
-		global_eth_addr.octets[1] = 0x08;
-		global_eth_addr.octets[2] = 0xdc;
-		global_eth_addr.octets[3] = 0x00;
-		global_eth_addr.octets[4] = 0x00;
-		global_eth_addr.octets[5] = 0x00;
-		setSHAR(global_eth_addr);
-	}
-
-	global_hostname[0]  = 'W';
-	global_hostname[1]  = 'I';
-	global_hostname[2]  = 'Z';
-	global_hostname[3]  = 'n';
-	global_hostname[4]  = 'e';
-	global_hostname[5]  = 't';
-	global_hostname[6]  = "0123456789ABCDEF"[(global_eth_addr.octets[3] >> 4)&0xF];
-	global_hostname[7]  = "0123456789ABCDEF"[(global_eth_addr.octets[3] >> 0)&0xF];
-	global_hostname[8]  = "0123456789ABCDEF"[(global_eth_addr.octets[4] >> 4)&0xF];
-	global_hostname[9]  = "0123456789ABCDEF"[(global_eth_addr.octets[4] >> 0)&0xF];
-	global_hostname[10] = "0123456789ABCDEF"[(global_eth_addr.octets[5] >> 4)&0xF];
-	global_hostname[11] = "0123456789ABCDEF"[(global_eth_addr.octets[5] >> 0)&0xF];
-	global_hostname[12] = '\0';
-
-	pDHCPMSG = buf;
-
-	global_xid = 0x12345678;
-	global_xid += global_eth_addr.octets[3];
-	global_xid += global_eth_addr.octets[4];
-	global_xid += global_eth_addr.octets[5];
-	global_xid += (global_eth_addr.octets[3] ^
-	               global_eth_addr.octets[4] ^
-	               global_eth_addr.octets[5]);
-
-	/* WIZchip Netinfo Clear */
-	setSIPR(net_ip4_addr_zero);
-	setGAR(net_ip4_addr_zero);
-
-	dhcp_reset_timeout();
-	dhcp_state = STATE_DHCP_INIT;
-}
-
-void DHCP_time_handler(void) {
-	dhcp_tick_1s++;
-}
diff --git a/libdhcp/include/libdhcp/dhcp.h b/libdhcp/include/libdhcp/dhcp.h
index e6b1801..aae4a4d 100644
--- a/libdhcp/include/libdhcp/dhcp.h
+++ b/libdhcp/include/libdhcp/dhcp.h
@@ -70,14 +70,6 @@
 #include <libmisc/net.h>
 #include "hw/w5500.h"
 
-struct dhcp_lease {
-	struct net_ip4_addr addr;
-	struct net_ip4_addr subnet_mask;
-	struct net_ip4_addr gateway;
-	struct net_ip4_addr dns;
-	uint32_t            lifetime; /* in seconds, except 0xffffffff is "infinity" */
-};
-
 enum dhcp_event {
 	DHCP_ASSIGN,
 	DHCP_UPDATE,
@@ -135,4 +127,32 @@ uint8_t DHCP_run(struct w5500 *chip, uint8_t socknum, dhcp_callback_t cb);
  */
 void    DHCP_stop(implements_net_packet_conn *sock);
 
+void xhandle(uint8_t opt_typ, uint8_t opt_len, uint8_t *opt_dat) {
+	switch (opt_typ) {
+	case DHCP_OPT_SUBNET_MASK:
+		if (opt_len != 4)
+			return;
+		global_lease.subnet_mask.octets[0] = opt_dat[0];
+		global_lease.subnet_mask.octets[1] = opt_dat[1];
+		global_lease.subnet_mask.octets[2] = opt_dat[2];
+		global_lease.subnet_mask.octets[3] = opt_dat[3];
+	case DHCP_OPT_ROUTER :
+		if (opt_len < 4)
+			return;
+		global_lease.gateway.octets[0] = opt_dat[0];
+		global_lease.gateway.octets[1] = opt_dat[1];
+		global_lease.gateway.octets[2] = opt_dat[2];
+		global_lease.gateway.octets[3] = opt_dat[3];
+		break;
+	case DHCP_OPT_DOMAIN_SERVER :
+		if (opt_len < 4)
+			return;
+		global_lease.dns.octets[0] = opt_dat[0];
+		global_lease.dns.octets[1] = opt_dat[1];
+		global_lease.dns.octets[2] = opt_dat[2];
+		global_lease.dns.octets[3] = opt_dat[3];
+		break;
+	}
+}
+
 #endif	/* _LIBDHCP_DHCP_H_ */