/*
   *	Based on LiMon - BOOTP.
   *
   *	Copyright 1994, 1995, 2000 Neil Russell.
   *	(See License)
   *	Copyright 2000 Roland Borde
   *	Copyright 2000 Paolo Scaffardi

   *	Copyright 2000-2004 Wolfgang Denk, wd@denx.de

   */

  #include <common.h>
  #include <command.h>
  #include <net.h>
  #include "bootp.h"
  #include "tftp.h"

  #include "nfs.h"

  #ifdef CONFIG_STATUS_LED
  #include <status_led.h>
  #endif

  #ifdef CONFIG_BOOTP_RANDOM_DELAY
  #include "net_rand.h"
  #endif

  #define BOOTP_VENDOR_MAGIC	0x63825363	/* RFC1048 Magic Cookie */

  #define TIMEOUT		5000UL	/* Milliseconds before trying BOOTP again */

  #ifndef CONFIG_NET_RETRY_COUNT

  # define TIMEOUT_COUNT	5		/* # of timeouts before giving up */

  #else

  # define TIMEOUT_COUNT	(CONFIG_NET_RETRY_COUNT)

  #endif

  #define PORT_BOOTPS	67		/* BOOTP server UDP port */
  #define PORT_BOOTPC	68		/* BOOTP client UDP port */

  #ifndef CONFIG_DHCP_MIN_EXT_LEN		/* minimal length of extension list */

  #define CONFIG_DHCP_MIN_EXT_LEN 64

  #endif
  
  ulong		BootpID;
  int		BootpTry;

  #if defined(CONFIG_CMD_DHCP)

  static dhcp_state_t dhcp_state = INIT;
  static unsigned long dhcp_leasetime;
  static IPaddr_t NetDHCPServerIP;

  static void DhcpHandler(uchar *pkt, unsigned dest, IPaddr_t sip, unsigned src,
  			unsigned len);

  
  /* For Debug */

  #if 0
  static char *dhcpmsg2str(int type)

  {
  	switch (type) {

  	case 1:	 return "DHCPDISCOVER"; break;
  	case 2:	 return "DHCPOFFER";	break;
  	case 3:	 return "DHCPREQUEST";	break;
  	case 4:	 return "DHCPDECLINE";	break;
  	case 5:	 return "DHCPACK";	break;
  	case 6:	 return "DHCPNACK";	break;
  	case 7:	 return "DHCPRELEASE";	break;

  	default: return "UNKNOWN/INVALID MSG TYPE"; break;
  	}
  }

  #endif

  #endif

  
  static int BootpCheckPkt(uchar *pkt, unsigned dest, unsigned src, unsigned len)
  {

  	struct Bootp_t *bp = (struct Bootp_t *) pkt;

  	int retval = 0;
  
  	if (dest != PORT_BOOTPC || src != PORT_BOOTPS)
  		retval = -1;

  	else if (len < sizeof(struct Bootp_t) - OPT_FIELD_SIZE)

  		retval = -2;
  	else if (bp->bp_op != OP_BOOTREQUEST &&

  			bp->bp_op != OP_BOOTREPLY &&
  			bp->bp_op != DHCP_OFFER &&
  			bp->bp_op != DHCP_ACK &&
  			bp->bp_op != DHCP_NAK)

  		retval = -3;

  	else if (bp->bp_htype != HWT_ETHER)
  		retval = -4;
  	else if (bp->bp_hlen != HWL_ETHER)
  		retval = -5;

  	else if (NetReadLong((ulong *)&bp->bp_id) != BootpID)

  		retval = -6;

  	debug("Filtering pkt = %d
  ", retval);

  
  	return retval;
  }
  
  /*
   * Copy parameters of interest from BOOTP_REPLY/DHCP_OFFER packet
   */

  static void BootpCopyNetParams(struct Bootp_t *bp)

  {

  #if !defined(CONFIG_BOOTP_SERVERIP)

  	IPaddr_t tmp_ip;

  	NetCopyIP(&tmp_ip, &bp->bp_siaddr);
  	if (tmp_ip != 0)
  		NetCopyIP(&NetServerIP, &bp->bp_siaddr);

  	memcpy(NetServerEther, ((struct ethernet_hdr *)NetRxPacket)->et_src, 6);

  #endif

  	NetCopyIP(&NetOurIP, &bp->bp_yiaddr);

  	if (strlen(bp->bp_file) > 0)

  		copy_filename(BootFile, bp->bp_file, sizeof(BootFile));

  	debug("Bootfile: %s
  ", BootFile);

  
  	/* Propagate to environment:

  	 * don't delete exising entry when BOOTP / DHCP reply does

  	 * not contain a new value
  	 */

  	if (*BootFile)
  		setenv("bootfile", BootFile);

  }

  static int truncate_sz(const char *name, int maxlen, int curlen)

  {
  	if (curlen >= maxlen) {

  		printf("*** WARNING: %s is too long (%d - max: %d)"
  			" - truncated
  ", name, curlen, maxlen);

  		curlen = maxlen - 1;
  	}

  	return curlen;

  }

  #if !defined(CONFIG_CMD_DHCP)

  static void BootpVendorFieldProcess(u8 *ext)

  {

  	int size = *(ext + 1);

  	debug("[BOOTP] Processing extension %d... (%d bytes)
  ", *ext,

  		*(ext + 1));

  	NetBootFileSize = 0;

  	switch (*ext) {
  		/* Fixed length fields */

  	case 1:			/* Subnet mask */

  		if (NetOurSubnetMask == 0)

  			NetCopyIP(&NetOurSubnetMask, (IPaddr_t *) (ext + 2));

  		break;

  	case 2:			/* Time offset - Not yet supported */

  		break;

  		/* Variable length fields */

  	case 3:			/* Gateways list */
  		if (NetOurGatewayIP == 0)
  			NetCopyIP(&NetOurGatewayIP, (IPaddr_t *) (ext + 2));

  		break;

  	case 4:			/* Time server - Not yet supported */

  		break;

  	case 5:			/* IEN-116 name server - Not yet supported */

  		break;
  	case 6:

  		if (NetOurDNSIP == 0)
  			NetCopyIP(&NetOurDNSIP, (IPaddr_t *) (ext + 2));

  #if defined(CONFIG_BOOTP_DNS2)

  		if ((NetOurDNS2IP == 0) && (size > 4))
  			NetCopyIP(&NetOurDNS2IP, (IPaddr_t *) (ext + 2 + 4));

  #endif

  		break;

  	case 7:			/* Log server - Not yet supported */

  		break;

  	case 8:			/* Cookie/Quote server - Not yet supported */

  		break;

  	case 9:			/* LPR server - Not yet supported */

  		break;

  	case 10:		/* Impress server - Not yet supported */

  		break;

  	case 11:		/* RPL server - Not yet supported */

  		break;

  	case 12:		/* Host name */

  		if (NetOurHostName[0] == 0) {

  			size = truncate_sz("Host Name",
  				sizeof(NetOurHostName), size);
  			memcpy(&NetOurHostName, ext + 2, size);

  			NetOurHostName[size] = 0;

  		}
  		break;

  	case 13:		/* Boot file size */

  		if (size == 2)

  			NetBootFileSize = ntohs(*(ushort *) (ext + 2));

  		else if (size == 4)

  			NetBootFileSize = ntohl(*(ulong *) (ext + 2));

  		break;

  	case 14:		/* Merit dump file - Not yet supported */

  		break;

  	case 15:		/* Domain name - Not yet supported */

  		break;

  	case 16:		/* Swap server - Not yet supported */

  		break;

  	case 17:		/* Root path */

  		if (NetOurRootPath[0] == 0) {

  			size = truncate_sz("Root Path",
  				sizeof(NetOurRootPath), size);
  			memcpy(&NetOurRootPath, ext + 2, size);

  			NetOurRootPath[size] = 0;

  		}
  		break;

  	case 18:		/* Extension path - Not yet supported */

  		/*

  		 * This can be used to send the information of the
  		 * vendor area in another file that the client can
  		 * access via TFTP.

  		 */
  		break;

  		/* IP host layer fields */

  	case 40:		/* NIS Domain name */

  		if (NetOurNISDomain[0] == 0) {

  			size = truncate_sz("NIS Domain Name",
  				sizeof(NetOurNISDomain), size);
  			memcpy(&NetOurNISDomain, ext + 2, size);

  			NetOurNISDomain[size] = 0;

  		}
  		break;

  #if defined(CONFIG_CMD_SNTP) && defined(CONFIG_BOOTP_NTPSERVER)
  	case 42:	/* NTP server IP */
  		NetCopyIP(&NetNtpServerIP, (IPaddr_t *) (ext + 2));
  		break;
  #endif

  		/* Application layer fields */

  	case 43:		/* Vendor specific info - Not yet supported */

  		/*

  		 * Binary information to exchange specific
  		 * product information.

  		 */
  		break;

  		/* Reserved (custom) fields (128..254) */
  	}

  }

  static void BootpVendorProcess(u8 *ext, int size)

  {

  	u8 *end = ext + size;

  	debug("[BOOTP] Checking extension (%d bytes)...
  ", size);

  	while ((ext < end) && (*ext != 0xff)) {
  		if (*ext == 0) {
  			ext++;
  		} else {
  			u8 *opt = ext;
  
  			ext += ext[1] + 2;
  			if (ext <= end)

  				BootpVendorFieldProcess(opt);

  		}

  	}

  	debug("[BOOTP] Received fields:
  ");

  	if (NetOurSubnetMask)

  		debug("NetOurSubnetMask : %pI4
  ", &NetOurSubnetMask);

  	if (NetOurGatewayIP)

  		debug("NetOurGatewayIP	: %pI4", &NetOurGatewayIP);

  	if (NetBootFileSize)
  		debug("NetBootFileSize : %d
  ", NetBootFileSize);

  	if (NetOurHostName[0])
  		debug("NetOurHostName  : %s
  ", NetOurHostName);

  	if (NetOurRootPath[0])
  		debug("NetOurRootPath  : %s
  ", NetOurRootPath);

  	if (NetOurNISDomain[0])
  		debug("NetOurNISDomain : %s
  ", NetOurNISDomain);

  	if (NetBootFileSize)
  		debug("NetBootFileSize: %d
  ", NetBootFileSize);

  
  #if defined(CONFIG_CMD_SNTP) && defined(CONFIG_BOOTP_NTPSERVER)
  	if (NetNtpServerIP)
  		debug("NetNtpServerIP : %pI4
  ", &NetNtpServerIP);
  #endif

  }

  /*
   *	Handle a BOOTP received packet.
   */
  static void

  BootpHandler(uchar *pkt, unsigned dest, IPaddr_t sip, unsigned src,
  	     unsigned len)

  {

  	struct Bootp_t *bp;

  	debug("got BOOTP packet (src=%d, dst=%d, len=%d want_len=%zu)
  ",

  		src, dest, len, sizeof(struct Bootp_t));

  	bp = (struct Bootp_t *)pkt;

  	/* Filter out pkts we don't want */
  	if (BootpCheckPkt(pkt, dest, src, len))

  		return;
  
  	/*

  	 *	Got a good BOOTP reply.	 Copy the data into our variables.

  	 */
  #ifdef CONFIG_STATUS_LED

  	status_led_set(STATUS_LED_BOOT, STATUS_LED_OFF);

  #endif
  
  	BootpCopyNetParams(bp);		/* Store net parameters from reply */
  
  	/* Retrieve extended information (we must parse the vendor area) */

  	if (NetReadLong((ulong *)&bp->bp_vend[0]) == htonl(BOOTP_VENDOR_MAGIC))

  		BootpVendorProcess((uchar *)&bp->bp_vend[4], len);

  
  	NetSetTimeout(0, (thand_f *)0);

  	bootstage_mark_name(BOOTSTAGE_ID_BOOTP_STOP, "bootp_stop");

  	debug("Got good BOOTP
  ");

  	net_auto_load();

  }

  #endif

  
  /*
   *	Timeout on BOOTP/DHCP request.
   */
  static void
  BootpTimeout(void)
  {
  	if (BootpTry >= TIMEOUT_COUNT) {

  #ifdef CONFIG_BOOTP_MAY_FAIL
  		puts("
  Retry count exceeded
  ");

  		net_set_state(NETLOOP_FAIL);

  #else

  		puts("
  Retry count exceeded; starting again
  ");
  		NetStartAgain();

  #endif

  	} else {

  		NetSetTimeout(TIMEOUT, BootpTimeout);
  		BootpRequest();

  	}
  }

  #define put_vci(e, str)						\
  	do {							\
  		size_t vci_strlen = strlen(str);		\
  		*e++ = 60;	/* Vendor Class Identifier */	\
  		*e++ = vci_strlen;				\
  		memcpy(e, str, vci_strlen);			\
  		e += vci_strlen;				\
  	} while (0)

  /*
   *	Initialize BOOTP extension fields in the request.
   */

  #if defined(CONFIG_CMD_DHCP)

  static int DhcpExtended(u8 *e, int message_type, IPaddr_t ServerID,
  			IPaddr_t RequestedIP)

  {

  	u8 *start = e;
  	u8 *cnt;

  #if defined(CONFIG_BOOTP_PXE)
  	char *uuid;

  	u16 clientarch;
  #endif

  #if defined(CONFIG_BOOTP_VENDOREX)

  	u8 *x;

  #endif

  #if defined(CONFIG_BOOTP_SEND_HOSTNAME)

  	char *hostname;

  #endif

  	*e++ = 99;		/* RFC1048 Magic Cookie */
  	*e++ = 130;
  	*e++ = 83;
  	*e++ = 99;

  	*e++ = 53;		/* DHCP Message Type */
  	*e++ = 1;
  	*e++ = message_type;

  	*e++ = 57;		/* Maximum DHCP Message Size */
  	*e++ = 2;

  	*e++ = (576 - 312 + OPT_FIELD_SIZE) >> 8;
  	*e++ = (576 - 312 + OPT_FIELD_SIZE) & 0xff;

  	if (ServerID) {

  		int tmp = ntohl(ServerID);

  		*e++ = 54;	/* ServerID */
  		*e++ = 4;
  		*e++ = tmp >> 24;
  		*e++ = tmp >> 16;
  		*e++ = tmp >> 8;
  		*e++ = tmp & 0xff;
  	}

  	if (RequestedIP) {

  		int tmp = ntohl(RequestedIP);

  		*e++ = 50;	/* Requested IP */
  		*e++ = 4;
  		*e++ = tmp >> 24;
  		*e++ = tmp >> 16;
  		*e++ = tmp >> 8;
  		*e++ = tmp & 0xff;
  	}

  #if defined(CONFIG_BOOTP_SEND_HOSTNAME)

  	hostname = getenv("hostname");
  	if (hostname) {
  		int hostnamelen = strlen(hostname);

  
  		*e++ = 12;	/* Hostname */
  		*e++ = hostnamelen;

  		memcpy(e, hostname, hostnamelen);

  		e += hostnamelen;
  	}

  #endif

  #if defined(CONFIG_BOOTP_PXE)
  	clientarch = CONFIG_BOOTP_PXE_CLIENTARCH;
  	*e++ = 93;	/* Client System Architecture */
  	*e++ = 2;
  	*e++ = (clientarch >> 8) & 0xff;
  	*e++ = clientarch & 0xff;
  
  	*e++ = 94;	/* Client Network Interface Identifier */
  	*e++ = 3;
  	*e++ = 1;	/* type field for UNDI */
  	*e++ = 0;	/* major revision */
  	*e++ = 0;	/* minor revision */
  
  	uuid = getenv("pxeuuid");
  
  	if (uuid) {
  		if (uuid_str_valid(uuid)) {
  			*e++ = 97;	/* Client Machine Identifier */
  			*e++ = 17;
  			*e++ = 0;	/* type 0 - UUID */
  
  			uuid_str_to_bin(uuid, e);
  			e += 16;
  		} else {
  			printf("Invalid pxeuuid: %s
  ", uuid);
  		}
  	}

  #endif

  #ifdef CONFIG_BOOTP_VCI_STRING
  	put_vci(e, CONFIG_BOOTP_VCI_STRING);

  #endif

  #if defined(CONFIG_BOOTP_VENDOREX)

  	x = dhcp_vendorex_prep(e);
  	if (x)

  		return x - start;

  #endif

  	*e++ = 55;		/* Parameter Request List */
  	 cnt = e++;		/* Pointer to count of requested items */
  	*cnt = 0;

  #if defined(CONFIG_BOOTP_SUBNETMASK)

  	*e++  = 1;		/* Subnet Mask */
  	*cnt += 1;

  #endif

  #if defined(CONFIG_BOOTP_TIMEOFFSET)

  	*e++  = 2;
  	*cnt += 1;
  #endif

  #if defined(CONFIG_BOOTP_GATEWAY)

  	*e++  = 3;		/* Router Option */
  	*cnt += 1;

  #endif

  #if defined(CONFIG_BOOTP_DNS)

  	*e++  = 6;		/* DNS Server(s) */
  	*cnt += 1;

  #endif

  #if defined(CONFIG_BOOTP_HOSTNAME)

  	*e++  = 12;		/* Hostname */
  	*cnt += 1;

  #endif

  #if defined(CONFIG_BOOTP_BOOTFILESIZE)

  	*e++  = 13;		/* Boot File Size */
  	*cnt += 1;

  #endif

  #if defined(CONFIG_BOOTP_BOOTPATH)

  	*e++  = 17;		/* Boot path */
  	*cnt += 1;

  #endif

  #if defined(CONFIG_BOOTP_NISDOMAIN)

  	*e++  = 40;		/* NIS Domain name request */
  	*cnt += 1;

  #endif

  #if defined(CONFIG_BOOTP_NTPSERVER)

  	*e++  = 42;
  	*cnt += 1;
  #endif

  	/* no options, so back up to avoid sending an empty request list */
  	if (*cnt == 0)
  		e -= 2;

  	*e++  = 255;		/* End of the list */

  	/* Pad to minimal length */

  #ifdef	CONFIG_DHCP_MIN_EXT_LEN

  	while ((e - start) < CONFIG_DHCP_MIN_EXT_LEN)

  		*e++ = 0;

  #endif

  	return e - start;

  }

  #else

  /*

   * Warning: no field size check - change CONFIG_BOOTP_* at your own risk!

   */

  static int BootpExtended(u8 *e)

  {

  	u8 *start = e;

  	*e++ = 99;		/* RFC1048 Magic Cookie */
  	*e++ = 130;
  	*e++ = 83;
  	*e++ = 99;

  #if defined(CONFIG_CMD_DHCP)

  	*e++ = 53;		/* DHCP Message Type */
  	*e++ = 1;
  	*e++ = DHCP_DISCOVER;
  
  	*e++ = 57;		/* Maximum DHCP Message Size */
  	*e++ = 2;

  	*e++ = (576 - 312 + OPT_FIELD_SIZE) >> 16;
  	*e++ = (576 - 312 + OPT_FIELD_SIZE) & 0xff;

  #endif

  #if defined(CONFIG_BOOTP_VCI_STRING) || \
  	(defined(CONFIG_SPL_BUILD) && defined(CONFIG_SPL_NET_VCI_STRING))
  #ifdef CONFIG_SPL_BUILD
  	put_vci(e, CONFIG_SPL_NET_VCI_STRING);
  #else

  	put_vci(e, CONFIG_BOOTP_VCI_STRING);
  #endif

  #endif

  #if defined(CONFIG_BOOTP_SUBNETMASK)

  	*e++ = 1;		/* Subnet mask request */
  	*e++ = 4;
  	e   += 4;

  #endif

  #if defined(CONFIG_BOOTP_GATEWAY)

  	*e++ = 3;		/* Default gateway request */
  	*e++ = 4;
  	e   += 4;

  #endif

  #if defined(CONFIG_BOOTP_DNS)

  	*e++ = 6;		/* Domain Name Server */
  	*e++ = 4;
  	e   += 4;

  #endif

  #if defined(CONFIG_BOOTP_HOSTNAME)

  	*e++ = 12;		/* Host name request */
  	*e++ = 32;
  	e   += 32;

  #endif

  #if defined(CONFIG_BOOTP_BOOTFILESIZE)

  	*e++ = 13;		/* Boot file size */
  	*e++ = 2;
  	e   += 2;

  #endif

  #if defined(CONFIG_BOOTP_BOOTPATH)

  	*e++ = 17;		/* Boot path */
  	*e++ = 32;
  	e   += 32;

  #endif

  #if defined(CONFIG_BOOTP_NISDOMAIN)

  	*e++ = 40;		/* NIS Domain name request */
  	*e++ = 32;
  	e   += 32;

  #endif

  #if defined(CONFIG_BOOTP_NTPSERVER)
  	*e++ = 42;
  	*e++ = 4;
  	e   += 4;
  #endif

  	*e++ = 255;		/* End of the list */

  	return e - start;

  }

  #endif

  
  void

  BootpRequest(void)

  {

  	uchar *pkt, *iphdr;

  	struct Bootp_t *bp;

  	int extlen, pktlen, iplen;
  	int eth_hdr_size;

  #ifdef CONFIG_BOOTP_RANDOM_DELAY
  	ulong i, rand_ms;
  #endif

  	bootstage_mark_name(BOOTSTAGE_ID_BOOTP_START, "bootp_start");

  #if defined(CONFIG_CMD_DHCP)

  	dhcp_state = INIT;
  #endif
  
  #ifdef CONFIG_BOOTP_RANDOM_DELAY		/* Random BOOTP delay */

  	if (BootpTry == 0)
  		srand_mac();

  	if (BootpTry <= 2)	/* Start with max 1024 * 1ms */
  		rand_ms = rand() >> (22 - BootpTry);
  	else		/* After 3rd BOOTP request max 8192 * 1ms */
  		rand_ms = rand() >> 19;

  	printf("Random delay: %ld ms...
  ", rand_ms);
  	for (i = 0; i < rand_ms; i++)

  		udelay(1000); /*Wait 1ms*/

  #endif	/* CONFIG_BOOTP_RANDOM_DELAY */
  
  	printf("BOOTP broadcast %d
  ", ++BootpTry);
  	pkt = NetTxPacket;

  	memset((void *)pkt, 0, PKTSIZE);

  	eth_hdr_size = NetSetEther(pkt, NetBcastAddr, PROT_IP);
  	pkt += eth_hdr_size;

  
  	/*

  	 * Next line results in incorrect packet size being transmitted,
  	 * resulting in errors in some DHCP servers, reporting missing bytes.
  	 * Size must be set in packet header after extension length has been
  	 * determined.

  	 * C. Hallinan, DS4.COM, Inc.
  	 */

  	/* net_set_udp_header(pkt, 0xFFFFFFFFL, PORT_BOOTPS, PORT_BOOTPC,

  		sizeof (struct Bootp_t)); */

  	iphdr = pkt;	/* We need this later for net_set_udp_header() */

  	pkt += IP_UDP_HDR_SIZE;

  	bp = (struct Bootp_t *)pkt;

  	bp->bp_op = OP_BOOTREQUEST;
  	bp->bp_htype = HWT_ETHER;
  	bp->bp_hlen = HWL_ETHER;
  	bp->bp_hops = 0;

  	bp->bp_secs = htons(get_timer(0) / 1000);

  	NetWriteIP(&bp->bp_ciaddr, 0);
  	NetWriteIP(&bp->bp_yiaddr, 0);
  	NetWriteIP(&bp->bp_siaddr, 0);
  	NetWriteIP(&bp->bp_giaddr, 0);

  	memcpy(bp->bp_chaddr, NetOurEther, 6);
  	copy_filename(bp->bp_file, BootFile, sizeof(bp->bp_file));

  
  	/* Request additional information from the BOOTP/DHCP server */

  #if defined(CONFIG_CMD_DHCP)

  	extlen = DhcpExtended((u8 *)bp->bp_vend, DHCP_DISCOVER, 0, 0);

  #else

  	extlen = BootpExtended((u8 *)bp->bp_vend);

  #endif

  
  	/*
  	 *	Bootp ID is the lower 4 bytes of our ethernet address

  	 *	plus the current time in ms.

  	 */
  	BootpID = ((ulong)NetOurEther[2] << 24)
  		| ((ulong)NetOurEther[3] << 16)
  		| ((ulong)NetOurEther[4] << 8)
  		| (ulong)NetOurEther[5];
  	BootpID += get_timer(0);

  	BootpID	 = htonl(BootpID);

  	NetCopyLong(&bp->bp_id, &BootpID);
  
  	/*
  	 * Calculate proper packet lengths taking into account the
  	 * variable size of the options field
  	 */

  	iplen = BOOTP_HDR_SIZE - OPT_FIELD_SIZE + extlen;
  	pktlen = eth_hdr_size + IP_UDP_HDR_SIZE + iplen;

  	net_set_udp_header(iphdr, 0xFFFFFFFFL, PORT_BOOTPS, PORT_BOOTPC, iplen);

  	NetSetTimeout(SELECT_TIMEOUT, BootpTimeout);

  #if defined(CONFIG_CMD_DHCP)

  	dhcp_state = SELECTING;

  	net_set_udp_handler(DhcpHandler);

  #else

  	net_set_udp_handler(BootpHandler);

  #endif

  	NetSendPacket(NetTxPacket, pktlen);
  }

  #if defined(CONFIG_CMD_DHCP)

  static void DhcpOptionsProcess(uchar *popt, struct Bootp_t *bp)

  {

  	uchar *end = popt + BOOTP_HDR_SIZE;

  	int oplen, size;

  #if defined(CONFIG_CMD_SNTP) && defined(CONFIG_BOOTP_TIMEOFFSET)
  	int *to_ptr;
  #endif

  	while (popt < end && *popt != 0xff) {

  		oplen = *(popt + 1);

  		switch (*popt) {
  		case 1:

  			NetCopyIP(&NetOurSubnetMask, (popt + 2));

  			break;

  #if defined(CONFIG_CMD_SNTP) && defined(CONFIG_BOOTP_TIMEOFFSET)

  		case 2:		/* Time offset	*/

  			to_ptr = &NetTimeOffset;

  			NetCopyLong((ulong *)to_ptr, (ulong *)(popt + 2));
  			NetTimeOffset = ntohl(NetTimeOffset);

  			break;
  #endif

  		case 3:

  			NetCopyIP(&NetOurGatewayIP, (popt + 2));

  			break;
  		case 6:

  			NetCopyIP(&NetOurDNSIP, (popt + 2));

  #if defined(CONFIG_BOOTP_DNS2)

  			if (*(popt + 1) > 4)
  				NetCopyIP(&NetOurDNS2IP, (popt + 2 + 4));

  #endif

  			break;
  		case 12:

  			size = truncate_sz("Host Name",
  				sizeof(NetOurHostName), oplen);
  			memcpy(&NetOurHostName, popt + 2, size);

  			NetOurHostName[size] = 0;
  			break;
  		case 15:	/* Ignore Domain Name Option */
  			break;
  		case 17:

  			size = truncate_sz("Root Path",
  				sizeof(NetOurRootPath), oplen);
  			memcpy(&NetOurRootPath, popt + 2, size);

  			NetOurRootPath[size] = 0;
  			break;

  		case 28:	/* Ignore Broadcast Address Option */
  			break;

  #if defined(CONFIG_CMD_SNTP) && defined(CONFIG_BOOTP_NTPSERVER)

  		case 42:	/* NTP server IP */

  			NetCopyIP(&NetNtpServerIP, (popt + 2));

  			break;
  #endif

  		case 51:

  			NetCopyLong(&dhcp_leasetime, (ulong *) (popt + 2));

  			break;
  		case 53:	/* Ignore Message Type Option */
  			break;
  		case 54:

  			NetCopyIP(&NetDHCPServerIP, (popt + 2));

  			break;
  		case 58:	/* Ignore Renewal Time Option */
  			break;
  		case 59:	/* Ignore Rebinding Time Option */
  			break;

  		case 66:	/* Ignore TFTP server name */
  			break;
  		case 67:	/* vendor opt bootfile */
  			/*
  			 * I can't use dhcp_vendorex_proc here because I need
  			 * to write into the bootp packet - even then I had to
  			 * pass the bootp packet pointer into here as the
  			 * second arg
  			 */

  			size = truncate_sz("Opt Boot File",

  					    sizeof(bp->bp_file),
  					    oplen);
  			if (bp->bp_file[0] == '\0' && size > 0) {
  				/*
  				 * only use vendor boot file if we didn't
  				 * receive a boot file in the main non-vendor
  				 * part of the packet - god only knows why
  				 * some vendors chose not to use this perfectly
  				 * good spot to store the boot file (join on
  				 * Tru64 Unix) it seems mind bogglingly crazy
  				 * to me
  				 */
  				printf("*** WARNING: using vendor "
  					"optional boot file
  ");
  				memcpy(bp->bp_file, popt + 2, size);
  				bp->bp_file[size] = '\0';
  			}
  			break;

  		default:

  #if defined(CONFIG_BOOTP_VENDOREX)

  			if (dhcp_vendorex_proc(popt))

  				break;

  #endif

  			printf("*** Unhandled DHCP Option in OFFER/ACK:"
  				" %d
  ", *popt);

  			break;

  		}
  		popt += oplen + 2;	/* Process next option */
  	}
  }
  
  static int DhcpMessageType(unsigned char *popt)
  {

  	if (NetReadLong((ulong *)popt) != htonl(BOOTP_VENDOR_MAGIC))

  		return -1;
  
  	popt += 4;

  	while (*popt != 0xff) {
  		if (*popt == 53)	/* DHCP Message Type */

  			return *(popt + 2);
  		popt += *(popt + 1) + 2;	/* Scan through all options */
  	}
  	return -1;
  }

  static void DhcpSendRequestPkt(struct Bootp_t *bp_offer)

  {

  	uchar *pkt, *iphdr;

  	struct Bootp_t *bp;

  	int pktlen, iplen, extlen;

  	int eth_hdr_size;

  	IPaddr_t OfferedIP;

  	debug("DhcpSendRequestPkt: Sending DHCPREQUEST
  ");

  	pkt = NetTxPacket;

  	memset((void *)pkt, 0, PKTSIZE);

  	eth_hdr_size = NetSetEther(pkt, NetBcastAddr, PROT_IP);
  	pkt += eth_hdr_size;

  	iphdr = pkt;	/* We'll need this later to set proper pkt size */

  	pkt += IP_UDP_HDR_SIZE;

  	bp = (struct Bootp_t *)pkt;

  	bp->bp_op = OP_BOOTREQUEST;
  	bp->bp_htype = HWT_ETHER;
  	bp->bp_hlen = HWL_ETHER;
  	bp->bp_hops = 0;

  	bp->bp_secs = htons(get_timer(0) / 1000);

  	/* Do not set the client IP, your IP, or server IP yet, since it
  	 * hasn't been ACK'ed by the server yet */

  	/*

  	 * RFC3046 requires Relay Agents to discard packets with
  	 * nonzero and offered giaddr
  	 */
  	NetWriteIP(&bp->bp_giaddr, 0);

  	memcpy(bp->bp_chaddr, NetOurEther, 6);

  
  	/*
  	 * ID is the id of the OFFER packet
  	 */
  
  	NetCopyLong(&bp->bp_id, &bp_offer->bp_id);
  
  	/*
  	 * Copy options from OFFER packet if present
  	 */

  
  	/* Copy offered IP into the parameters request list */
  	NetCopyIP(&OfferedIP, &bp_offer->bp_yiaddr);

  	extlen = DhcpExtended((u8 *)bp->bp_vend, DHCP_REQUEST,
  		NetDHCPServerIP, OfferedIP);

  	iplen = BOOTP_HDR_SIZE - OPT_FIELD_SIZE + extlen;
  	pktlen = eth_hdr_size + IP_UDP_HDR_SIZE + iplen;

  	net_set_udp_header(iphdr, 0xFFFFFFFFL, PORT_BOOTPS, PORT_BOOTPC, iplen);

  #ifdef CONFIG_BOOTP_DHCP_REQUEST_DELAY
  	udelay(CONFIG_BOOTP_DHCP_REQUEST_DELAY);
  #endif	/* CONFIG_BOOTP_DHCP_REQUEST_DELAY */

  	debug("Transmitting DHCPREQUEST packet: len = %d
  ", pktlen);

  	NetSendPacket(NetTxPacket, pktlen);
  }
  
  /*
   *	Handle DHCP received packets.
   */
  static void

  DhcpHandler(uchar *pkt, unsigned dest, IPaddr_t sip, unsigned src,
  	    unsigned len)

  {

  	struct Bootp_t *bp = (struct Bootp_t *)pkt;

  	debug("DHCPHandler: got packet: (src=%d, dst=%d, len=%d) state: %d
  ",

  		src, dest, len, dhcp_state);

  	/* Filter out pkts we don't want */
  	if (BootpCheckPkt(pkt, dest, src, len))

  		return;

  	debug("DHCPHandler: got DHCP packet: (src=%d, dst=%d, len=%d) state:"
  		" %d
  ", src, dest, len, dhcp_state);

  
  	switch (dhcp_state) {
  	case SELECTING:
  		/*
  		 * Wait an appropriate time for any potential DHCPOFFER packets

  		 * to arrive.  Then select one, and generate DHCPREQUEST
  		 * response.  If filename is in format we recognize, assume it
  		 * is a valid OFFER from a server we want.

  		 */

  		debug("DHCP: state=SELECTING bp_file: \"%s\"
  ", bp->bp_file);

  #ifdef CONFIG_SYS_BOOTFILE_PREFIX

  		if (strncmp(bp->bp_file,

  			    CONFIG_SYS_BOOTFILE_PREFIX,

  			    strlen(CONFIG_SYS_BOOTFILE_PREFIX)) == 0) {

  #endif	/* CONFIG_SYS_BOOTFILE_PREFIX */

  			debug("TRANSITIONING TO REQUESTING STATE
  ");

  			dhcp_state = REQUESTING;

  			if (NetReadLong((ulong *)&bp->bp_vend[0]) ==
  						htonl(BOOTP_VENDOR_MAGIC))

  				DhcpOptionsProcess((u8 *)&bp->bp_vend[4], bp);

  			NetSetTimeout(TIMEOUT, BootpTimeout);

  			DhcpSendRequestPkt(bp);

  #ifdef CONFIG_SYS_BOOTFILE_PREFIX

  		}

  #endif	/* CONFIG_SYS_BOOTFILE_PREFIX */

  
  		return;
  		break;
  	case REQUESTING:

  		debug("DHCP State: REQUESTING
  ");

  		if (DhcpMessageType((u8 *)bp->bp_vend) == DHCP_ACK) {
  			if (NetReadLong((ulong *)&bp->bp_vend[0]) ==
  						htonl(BOOTP_VENDOR_MAGIC))

  				DhcpOptionsProcess((u8 *)&bp->bp_vend[4], bp);

  			/* Store net params from reply */
  			BootpCopyNetParams(bp);

  			dhcp_state = BOUND;

  			printf("DHCP client bound to address %pI4
  ",
  				&NetOurIP);

  			bootstage_mark_name(BOOTSTAGE_ID_BOOTP_STOP,

  				"bootp_stop");

  			net_auto_load();

  			return;
  		}
  		break;

  	case BOUND:
  		/* DHCP client bound to address */
  		break;

  	default:

  		puts("DHCP: INVALID STATE
  ");

  		break;
  	}
  
  }
  
  void DhcpRequest(void)
  {
  	BootpRequest();
  }

  #endif	/* CONFIG_CMD_DHCP */