net/bootp.c

/*
 *	Based on LiMon - BOOTP.
 *
 *	Copyright 1994, 1995, 2000 Neil Russell.
 *	(See License)
 *	Copyright 2000 Roland Borde
 *	Copyright 2000 Paolo Scaffardi
 *	Copyright 2000-2002 Wolfgang Denk, wd@denx.de
 */

#if 0
#define	DEBUG		1	/* general debug */
#define DEBUG_BOOTP_EXT	1	/* Debug received vendor fields	*/
#endif

#ifdef DEBUG_BOOTP_EXT
#define debug_ext(fmt,args...)	printf (fmt ,##args)
#else
#define debug_ext(fmt,args...)
#endif

#include <common.h>
#include <command.h>
#include <net.h>
#include "bootp.h"
#include "tftp.h"
#ifdef CONFIG_STATUS_LED
#include <status_led.h>
#endif

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

#if (CONFIG_COMMANDS & CFG_CMD_NET)

#define TIMEOUT		5		/* Seconds 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;
#ifdef CONFIG_BOOTP_RANDOM_DELAY
ulong		seed1, seed2;
#endif

#if (CONFIG_COMMANDS & CFG_CMD_DHCP)
dhcp_state_t dhcp_state = INIT;
unsigned long dhcp_leasetime = 0;
IPaddr_t NetDHCPServerIP = 0;
static void DhcpHandler(uchar * pkt, unsigned dest, 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

#if (CONFIG_BOOTP_MASK & CONFIG_BOOTP_VENDOREX)
extern u8 *dhcp_vendorex_prep (u8 *e); /*rtn new e after add own opts. */
extern u8 *dhcp_vendorex_proc (u8 *e); /*rtn next e if mine,else NULL  */
#endif

#endif	/* CFG_CMD_DHCP */

static int BootpCheckPkt(uchar *pkt, unsigned dest, unsigned src, unsigned len)
{
	Bootp_t *bp = (Bootp_t *) pkt;
	int retval = 0;

	if (dest != PORT_BOOTPC || src != PORT_BOOTPS)
		retval = -1;
	else if (len < sizeof (Bootp_t) - OPT_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\n", retval);

	return retval;
}

/*
 * Copy parameters of interest from BOOTP_REPLY/DHCP_OFFER packet
 */
static void BootpCopyNetParams(Bootp_t *bp)
{
	NetCopyIP(&NetOurIP, &bp->bp_yiaddr);
	NetCopyIP(&NetServerIP, &bp->bp_siaddr);
	memcpy (NetServerEther, ((Ethernet_t *)NetRxPkt)->et_src, 6);
	copy_filename (BootFile, bp->bp_file, sizeof(BootFile));

	debug ("Bootfile: %s\n", 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\n",
			name, curlen, maxlen);
		curlen = maxlen - 1;
	}
	return (curlen);
}

#if !(CONFIG_COMMANDS & CFG_CMD_DHCP)

static void BootpVendorFieldProcess(u8 *ext)
{
    int size = *(ext+1) ;

    debug_ext ("[BOOTP] Processing extension %d... (%d bytes)\n", *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 (CONFIG_BOOTP_MASK & 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;
    /* 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_ext ("[BOOTP] Checking extension (%d bytes)...\n", size);

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

#ifdef DEBUG_BOOTP_EXT
    printf("[BOOTP] Received fields: \n");
    if (NetOurSubnetMask) {
	puts ("NetOurSubnetMask	: ");
	print_IPaddr (NetOurSubnetMask);
	putc('\n');
    }

    if (NetOurGatewayIP) {
	puts ("NetOurGatewayIP	: ");
	print_IPaddr (NetOurGatewayIP);
	putc('\n');
    }

    if (NetBootFileSize) {
	printf("NetBootFileSize : %d\n", NetBootFileSize);
    }

    if (NetOurHostName[0]) {
	printf("NetOurHostName  : %s\n", NetOurHostName);
    }

    if (NetOurRootPath[0]) {
	printf("NetOurRootPath  : %s\n", NetOurRootPath);
    }

    if (NetOurNISDomain[0]) {
	printf("NetOurNISDomain : %s\n", NetOurNISDomain);
    }

    if (NetBootFileSize) {
	printf("NetBootFileSize: %d\n", NetBootFileSize);
    }
#endif	/* DEBUG_BOOTP_EXT */
}

/*
 *	Handle a BOOTP received packet.
 */
static void
BootpHandler(uchar * pkt, unsigned dest, unsigned src, unsigned len)
{
	Bootp_t *bp;
	char	*s;

	debug ("got BOOTP packet (src=%d, dst=%d, len=%d want_len=%d)\n",
		src, dest, len, sizeof (Bootp_t));

	bp = (Bootp_t *)pkt;

	if (BootpCheckPkt(pkt, dest, src, len))	/* Filter out pkts we don't want */
		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(&bp->bp_vend[4], len);

	NetSetTimeout(0, (thand_f *)0);

	debug ("Got good BOOTP\n");

	if (((s = getenv("autoload")) != NULL) && (*s == 'n')) {
		/*
		 * Just use BOOTP to configure system;
		 * Do not use TFTP to load the bootfile.
		 */
		NetState = NETLOOP_SUCCESS;
		return;
	}

	TftpStart();
}
#endif	/* !CFG_CMD_DHCP */

/*
 *	Timeout on BOOTP/DHCP request.
 */
static void
BootpTimeout(void)
{
	if (BootpTry >= TIMEOUT_COUNT) {
		puts ("\nRetry count exceeded; starting again\n");
		NetStartAgain ();
	} else {
		NetSetTimeout (TIMEOUT * CFG_HZ, BootpTimeout);
		BootpRequest ();
	}
}

/*
 *	Initialize BOOTP extension fields in the request.
 */
#if (CONFIG_COMMANDS & CFG_CMD_DHCP)
static int DhcpExtended(u8 *e, int message_type, IPaddr_t ServerID, IPaddr_t RequestedIP)
{
    u8 *start = e ;
    u8 *cnt;
#if (CONFIG_BOOTP_MASK & CONFIG_BOOTP_VENDOREX)
    u8 *x;
#endif
#if (CONFIG_BOOTP_MASK & CONFIG_BOOTP_SEND_HOSTNAME)
    uchar *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_SIZE) >> 8;
    *e++ = (576-312+OPT_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 (CONFIG_BOOTP_MASK & CONFIG_BOOTP_SEND_HOSTNAME)
    if ( (hostname = getenv("hostname")) ) {
	    int hostnamelen = strlen(hostname);
	    *e++ = 12;        /* Hostname */
	    *e++ = hostnamelen;
	    memcpy(e,hostname,hostnamelen);
	    e += hostnamelen;
    }
#endif

#if (CONFIG_BOOTP_MASK & CONFIG_BOOTP_VENDOREX)
    if ((x = dhcp_vendorex_prep (e)))
	return x - start ;
#endif

    *e++ = 55;		/* Parameter Request List */
    cnt  = e++;		/* Pointer to count of requested items */
    *cnt = 0;
#if (CONFIG_BOOTP_MASK & CONFIG_BOOTP_SUBNETMASK)
    *e++ = 1;		/* Subnet Mask */
    *cnt += 1;
#endif
#if (CONFIG_BOOTP_MASK & CONFIG_BOOTP_GATEWAY)
    *e++ = 3;		/* Router Option */
    *cnt += 1;
#endif
#if (CONFIG_BOOTP_MASK & CONFIG_BOOTP_DNS)
    *e++ = 6;		/* DNS Server(s) */
    *cnt += 1;
#endif
#if (CONFIG_BOOTP_MASK & CONFIG_BOOTP_HOSTNAME)
    *e++ = 12;		/* Hostname */
    *cnt += 1;
#endif
#if (CONFIG_BOOTP_MASK & CONFIG_BOOTP_BOOTFILESIZE)
    *e++ = 13;		/* Boot File Size */
    *cnt += 1;
#endif
#if (CONFIG_BOOTP_MASK & CONFIG_BOOTP_BOOTPATH)
    *e++ = 17;		/* Boot path */
    *cnt += 1;
#endif
#if (CONFIG_BOOTP_MASK & CONFIG_BOOTP_NISDOMAIN)
    *e++ = 40;		/* NIS Domain name request */
    *cnt += 1;
#endif
    *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	/* CFG_CMD_DHCP */
/*
 *	Warning: no field size check - change CONFIG_BOOTP_MASK at your own risk!
 */
static int BootpExtended (u8 *e)
{
    u8 *start = e ;

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

#if (CONFIG_COMMANDS & CFG_CMD_DHCP)
    *e++ = 53;		/* DHCP Message Type */
    *e++ = 1;
    *e++ = DHCP_DISCOVER;

    *e++ = 57;		/* Maximum DHCP Message Size */
    *e++ = 2;
    *e++ = (576-312+OPT_SIZE) >> 16;
    *e++ = (576-312+OPT_SIZE) & 0xff;
#endif	/* CFG_CMD_DHCP */

#if (CONFIG_BOOTP_MASK & CONFIG_BOOTP_SUBNETMASK)
    *e++ =  1;		/* Subnet mask request */
    *e++ =  4;
     e  +=  4;
#endif

#if (CONFIG_BOOTP_MASK & CONFIG_BOOTP_GATEWAY)
    *e++ =  3;		/* Default gateway request */
    *e++ =  4;
     e  +=  4;
#endif

#if (CONFIG_BOOTP_MASK & CONFIG_BOOTP_DNS)
    *e++ =  6;		/* Domain Name Server */
    *e++ =  4;
     e  +=  4;
#endif

#if (CONFIG_BOOTP_MASK & CONFIG_BOOTP_HOSTNAME)
    *e++ = 12;		/* Host name request */
    *e++ = 32;
     e  += 32;
#endif

#if (CONFIG_BOOTP_MASK & CONFIG_BOOTP_BOOTFILESIZE)
    *e++ = 13;		/* Boot file size */
    *e++ =  2;
     e  +=  2;
#endif

#if (CONFIG_BOOTP_MASK & CONFIG_BOOTP_BOOTPATH)
    *e++ = 17;		/* Boot path */
    *e++ = 32;
     e  += 32;
#endif

#if (CONFIG_BOOTP_MASK & CONFIG_BOOTP_NISDOMAIN)
    *e++ = 40;		/* NIS Domain name request */
    *e++ = 32;
     e  += 32;
#endif

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

    return e - start ;
}
#endif	/* CFG_CMD_DHCP */

void
BootpRequest (void)
{
	volatile uchar *pkt, *iphdr;
	Bootp_t *bp;
	int ext_len, pktlen, iplen;

#if (CONFIG_COMMANDS & CFG_CMD_DHCP)
	dhcp_state = INIT;
#endif

#ifdef CONFIG_BOOTP_RANDOM_DELAY		/* Random BOOTP delay */
	unsigned char bi_enetaddr[6];
	int   reg;
	char  *e,*s;
	uchar tmp[64];
	ulong tst1, tst2, sum, m_mask, m_value = 0;

	if (BootpTry ==0) {
		/* get our mac */
		reg = getenv_r ("ethaddr", tmp, sizeof(tmp));
		s = (reg > 0) ? tmp : NULL;

		for (reg=0; reg<6; ++reg) {
			bi_enetaddr[reg] = s ? simple_strtoul(s, &e, 16) : 0;
			if (s) {
				s = (*e) ? e+1 : e;
			}
		}
#ifdef DEBUG
		printf("BootpRequest => Our Mac: ");
		for (reg=0; reg<6; reg++) {
			printf ("%x%c",
				bi_enetaddr[reg],
				reg==5 ? '\n' : ':');
		}
#endif /* DEBUG */

		/* Mac-Manipulation 2 get seed1 */
		tst1=0;
		tst2=0;
		for (reg=2; reg<6; reg++) {
			tst1 = tst1 << 8;
			tst1 = tst1 | bi_enetaddr[reg];
		}
		for (reg=0; reg<2; reg++) {
			tst2 = tst2 | bi_enetaddr[reg];
			tst2 = tst2 << 8;
		}

		seed1 = tst1^tst2;

		/* Mirror seed1*/
		m_mask=0x1;
		for (reg=1;reg<=32;reg++) {
			m_value |= (m_mask & seed1);
			seed1 = seed1 >> 1;
			m_value = m_value << 1;
		}
		seed1 = m_value;
		seed2 = 0xB78D0945;
	}

	/* Random Number Generator */

	for (reg=0;reg<=0;reg++) {
		sum = seed1 + seed2;
		if (sum < seed1 || sum < seed2)
			sum++;
		seed2 = seed1;
		seed1 = sum;

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

	printf ("Random delay: %ld ms...\n", sum);
	for (reg=0; reg <sum; reg++) {
		udelay(1000); /*Wait 1ms*/
	}
#endif	/* CONFIG_BOOTP_RANDOM_DELAY */

	printf("BOOTP broadcast %d\n", ++BootpTry);
	pkt = NetTxPacket;
	memset ((void*)pkt, 0, PKTSIZE);

	NetSetEther(pkt, NetBcastAddr, PROT_IP);
	pkt += ETHER_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.
	 */
	/* NetSetIP(pkt, 0xFFFFFFFFL, PORT_BOOTPS, PORT_BOOTPC, sizeof (Bootp_t)); */
	iphdr = pkt;	/* We need this later for NetSetIP() */
	pkt += IP_HDR_SIZE;

	bp = (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) / CFG_HZ);
	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 (CONFIG_COMMANDS & CFG_CMD_DHCP)
	ext_len = DhcpExtended(bp->bp_vend, DHCP_DISCOVER, 0, 0);
#else
	ext_len = BootpExtended(bp->bp_vend);
#endif	/* CFG_CMD_DHCP */

	/*
	 *	Bootp ID is the lower 4 bytes of our ethernet address
	 *	plus the current time in HZ.
	 */
	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
	 */
	pktlen = BOOTP_SIZE - sizeof(bp->bp_vend) + ext_len;
	iplen = BOOTP_HDR_SIZE - sizeof(bp->bp_vend) + ext_len;
	NetSetIP(iphdr, 0xFFFFFFFFL, PORT_BOOTPS, PORT_BOOTPC, iplen);
	NetSetTimeout(SELECT_TIMEOUT * CFG_HZ, BootpTimeout);

#if (CONFIG_COMMANDS & CFG_CMD_DHCP)
	dhcp_state = SELECTING;
	NetSetHandler(DhcpHandler);
#else
	NetSetHandler(BootpHandler);
#endif	/* CFG_CMD_DHCP */
	NetSendPacket(NetTxPacket, pktlen);
}

#if (CONFIG_COMMANDS & CFG_CMD_DHCP)
static void DhcpOptionsProcess(uchar *popt)
{
	uchar *end = popt + BOOTP_HDR_SIZE;
	int oplen, size;

	while ( popt < end && *popt != 0xff ) {
		oplen = *(popt + 1);
		switch(*popt) {
			case  1:
				NetCopyIP(&NetOurSubnetMask, (popt+2));
				break;
			case  3:
				NetCopyIP(&NetOurGatewayIP, (popt+2));
				break;
			case  6:
				NetCopyIP(&NetOurDNSIP, (popt+2));
#if (CONFIG_BOOTP_MASK & 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 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;
			default:
#if (CONFIG_BOOTP_MASK & CONFIG_BOOTP_VENDOREX)
			    if (dhcp_vendorex_proc(popt))
				break;
#endif
				printf("*** Unhandled DHCP Option in OFFER/ACK: %d\n",
					*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(Bootp_t *bp_offer)
{
	volatile uchar *pkt, *iphdr;
	Bootp_t *bp;
	int pktlen, iplen, extlen;
	IPaddr_t OfferedIP;

	debug ("DhcpSendRequestPkt: Sending DHCPREQUEST\n");
	pkt = NetTxPacket;
	memset ((void*)pkt, 0, PKTSIZE);

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

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

	bp = (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) / CFG_HZ);
	NetCopyIP(&bp->bp_ciaddr, &bp_offer->bp_ciaddr); /* both in network byte order */
	NetCopyIP(&bp->bp_yiaddr, &bp_offer->bp_yiaddr);
	NetCopyIP(&bp->bp_siaddr, &bp_offer->bp_siaddr);
	NetCopyIP(&bp->bp_giaddr, &bp_offer->bp_giaddr);
	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
	 */
	NetCopyIP(&OfferedIP, &bp->bp_yiaddr);
	extlen = DhcpExtended(bp->bp_vend, DHCP_REQUEST, NetDHCPServerIP, OfferedIP);

	pktlen = BOOTP_SIZE - sizeof(bp->bp_vend) + extlen;
	iplen = BOOTP_HDR_SIZE - sizeof(bp->bp_vend) + extlen;
	NetSetIP(iphdr, 0xFFFFFFFFL, PORT_BOOTPS, PORT_BOOTPC, iplen);

	debug ("Transmitting DHCPREQUEST packet: len = %d\n", pktlen);
	NetSendPacket(NetTxPacket, pktlen);
}

/*
 *	Handle DHCP received packets.
 */
static void
DhcpHandler(uchar * pkt, unsigned dest, unsigned src, unsigned len)
{
	Bootp_t *bp = (Bootp_t *)pkt;

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

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

	debug ("DHCPHandler: got DHCP packet: (src=%d, dst=%d, len=%d) state: %d\n",
		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\"\n", bp->bp_file);
#ifdef CFG_BOOTFILE_PREFIX
		if (strncmp(bp->bp_file,
			    CFG_BOOTFILE_PREFIX,
			    strlen(CFG_BOOTFILE_PREFIX)) == 0 ) {
#endif	/* CFG_BOOTFILE_PREFIX */

			debug ("TRANSITIONING TO REQUESTING STATE\n");
			dhcp_state = REQUESTING;

			if (NetReadLong((ulong*)&bp->bp_vend[0]) == htonl(BOOTP_VENDOR_MAGIC))
				DhcpOptionsProcess(&bp->bp_vend[4]);

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

			NetSetTimeout(TIMEOUT * CFG_HZ, BootpTimeout);
			DhcpSendRequestPkt(bp);
#ifdef CFG_BOOTFILE_PREFIX
		}
#endif	/* CFG_BOOTFILE_PREFIX */

		return;
		break;
	case REQUESTING:
		debug ("DHCP State: REQUESTING\n");

		if ( DhcpMessageType(bp->bp_vend) == DHCP_ACK ) {
			char *s;

			if (NetReadLong((ulong*)&bp->bp_vend[0]) == htonl(BOOTP_VENDOR_MAGIC))
				DhcpOptionsProcess(&bp->bp_vend[4]);
			BootpCopyNetParams(bp);	/* Store net params from reply */
			dhcp_state = BOUND;
			printf("DHCP client bound to address ");
			print_IPaddr(NetOurIP);
			printf("\n");

			/* Obey the 'autoload' setting */
			if (((s = getenv("autoload")) != NULL) && (*s == 'n')) {
				NetState = NETLOOP_SUCCESS;
				return;
			}
			TftpStart();
			return;
		}
		break;
	default:
		printf("DHCP: INVALID STATE\n");
		break;
	}

}

void DhcpRequest(void)
{
	BootpRequest();
}
#endif	/* CFG_CMD_DHCP */

#endif /* CFG_CMD_NET */