/*
   *	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 <efi_loader.h>

  #include <net.h>

  #include <net/tftp.h>

  #include "bootp.h"

  #ifdef CONFIG_LED_STATUS

  #include <status_led.h>
  #endif

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

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

  /*
   * The timeout for the initial BOOTP/DHCP request used to be described by a
   * counter of fixed-length timeout periods. TIMEOUT_COUNT represents
   * that counter
   *
   * Now that the timeout periods are variable (exponential backoff and retry)
   * we convert the timeout count to the absolute time it would have take to
   * execute that many retries, and keep sending retry packets until that time
   * is reached.
   */

  #ifndef CONFIG_NET_RETRY_COUNT

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

  #else

  # define TIMEOUT_COUNT	(CONFIG_NET_RETRY_COUNT)

  #endif

  #define TIMEOUT_MS	((3 + (TIMEOUT_COUNT * 5)) * 1000)

  #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

  #ifndef CONFIG_BOOTP_ID_CACHE_SIZE
  #define CONFIG_BOOTP_ID_CACHE_SIZE 4
  #endif

  u32		bootp_ids[CONFIG_BOOTP_ID_CACHE_SIZE];

  unsigned int	bootp_num_ids;

  int		bootp_try;

  ulong		bootp_start;
  ulong		bootp_timeout;

  char net_nis_domain[32] = {0,}; /* Our NIS domain */
  char net_hostname[32] = {0,}; /* Our hostname */
  char net_root_path[64] = {0,}; /* Our bootpath */

  static ulong time_taken_max;

  #if defined(CONFIG_CMD_DHCP)

  static dhcp_state_t dhcp_state = INIT;

  static u32 dhcp_leasetime;

  static struct in_addr dhcp_server_ip;

  static u8 dhcp_option_overload;
  #define OVERLOAD_FILE 1
  #define OVERLOAD_SNAME 2

  static void dhcp_handler(uchar *pkt, unsigned dest, struct in_addr 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 void bootp_add_id(ulong id)
  {
  	if (bootp_num_ids >= ARRAY_SIZE(bootp_ids)) {
  		size_t size = sizeof(bootp_ids) - sizeof(id);
  
  		memmove(bootp_ids, &bootp_ids[1], size);
  		bootp_ids[bootp_num_ids - 1] = id;
  	} else {
  		bootp_ids[bootp_num_ids] = id;
  		bootp_num_ids++;
  	}
  }
  
  static bool bootp_match_id(ulong id)
  {
  	unsigned int i;
  
  	for (i = 0; i < bootp_num_ids; i++)
  		if (bootp_ids[i] == id)
  			return true;
  
  	return false;
  }

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

  {

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

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

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

  		retval = -2;

  	else if (bp->bp_op != OP_BOOTREPLY)

  		retval = -3;

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

  	else if (!bootp_match_id(net_read_u32(&bp->bp_id)))

  		retval = -6;

  	else if (memcmp(bp->bp_chaddr, net_ethaddr, HWL_ETHER) != 0)
  		retval = -7;

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

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

  static void store_net_params(struct bootp_hdr *bp)

  {

  #if !defined(CONFIG_BOOTP_SERVERIP)

  	struct in_addr tmp_ip;

  	bool overwrite_serverip = true;
  
  #if defined(CONFIG_BOOTP_PREFER_SERVERIP)
  	overwrite_serverip = false;
  #endif

  	net_copy_ip(&tmp_ip, &bp->bp_siaddr);

  	if (tmp_ip.s_addr != 0 && (overwrite_serverip || !net_server_ip.s_addr))

  		net_copy_ip(&net_server_ip, &bp->bp_siaddr);

  	memcpy(net_server_ethaddr,
  	       ((struct ethernet_hdr *)net_rx_packet)->et_src, 6);

  	if (
  #if defined(CONFIG_CMD_DHCP)
  	    !(dhcp_option_overload & OVERLOAD_FILE) &&
  #endif

  	    (strlen(bp->bp_file) > 0) &&
  	    !net_boot_file_name_explicit) {

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

  	}

  	debug("net_boot_file_name: %s
  ", net_boot_file_name);

  
  	/* Propagate to environment:

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

  	 * not contain a new value
  	 */

  	if (*net_boot_file_name)

  		env_set("bootfile", net_boot_file_name);

  #endif

  	net_copy_ip(&net_ip, &bp->bp_yiaddr);

  }

  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 bootp_process_vendor_field(u8 *ext)

  {

  	int size = *(ext + 1);

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

  	      *(ext + 1));

  	net_boot_file_expected_size_in_blocks = 0;

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

  	case 1:			/* Subnet mask */

  		if (net_netmask.s_addr == 0)
  			net_copy_ip(&net_netmask, (struct in_addr *)(ext + 2));

  		break;

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

  		break;

  		/* Variable length fields */

  	case 3:			/* Gateways list */

  		if (net_gateway.s_addr == 0)
  			net_copy_ip(&net_gateway, (struct in_addr *)(ext + 2));

  		break;

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

  		break;

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

  		break;
  	case 6:

  		if (net_dns_server.s_addr == 0)
  			net_copy_ip(&net_dns_server,
  				    (struct in_addr *)(ext + 2));

  #if defined(CONFIG_BOOTP_DNS2)

  		if ((net_dns_server2.s_addr == 0) && (size > 4))
  			net_copy_ip(&net_dns_server2,
  				    (struct in_addr *)(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 (net_hostname[0] == 0) {

  			size = truncate_sz("Host Name",

  				sizeof(net_hostname), size);
  			memcpy(&net_hostname, ext + 2, size);
  			net_hostname[size] = 0;

  		}
  		break;

  	case 13:		/* Boot file size */

  		if (size == 2)

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

  		else if (size == 4)

  			net_boot_file_expected_size_in_blocks =
  				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 (net_root_path[0] == 0) {

  			size = truncate_sz("Root Path",

  				sizeof(net_root_path), size);
  			memcpy(&net_root_path, ext + 2, size);
  			net_root_path[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 (net_nis_domain[0] == 0) {

  			size = truncate_sz("NIS Domain Name",

  				sizeof(net_nis_domain), size);
  			memcpy(&net_nis_domain, ext + 2, size);
  			net_nis_domain[size] = 0;

  		}
  		break;

  #if defined(CONFIG_CMD_SNTP) && defined(CONFIG_BOOTP_NTPSERVER)
  	case 42:	/* NTP server IP */

  		net_copy_ip(&net_ntp_server, (struct in_addr *)(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 bootp_process_vendor(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)

  				bootp_process_vendor_field(opt);

  		}

  	}

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

  	if (net_netmask.s_addr)
  		debug("net_netmask : %pI4
  ", &net_netmask);

  	if (net_gateway.s_addr)
  		debug("net_gateway	: %pI4", &net_gateway);

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

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

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

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

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

  	if (net_ntp_server.s_addr)

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

  #endif

  }

  /*
   *	Handle a BOOTP received packet.
   */

  static void bootp_handler(uchar *pkt, unsigned dest, struct in_addr sip,
  			  unsigned src, unsigned len)

  {

  	struct bootp_hdr *bp;

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

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

  	bp = (struct bootp_hdr *)pkt;

  	/* Filter out pkts we don't want */

  	if (check_reply_packet(pkt, dest, src, len))

  		return;
  
  	/*

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

  	 */

  #if defined(CONFIG_LED_STATUS) && defined(CONFIG_LED_STATUS_BOOT_ENABLE)
  	status_led_set(CONFIG_LED_STATUS_BOOT, CONFIG_LED_STATUS_OFF);

  #endif

  	store_net_params(bp);		/* Store net parameters from reply */

  
  	/* Retrieve extended information (we must parse the vendor area) */

  	if (net_read_u32((u32 *)&bp->bp_vend[0]) == htonl(BOOTP_VENDOR_MAGIC))

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

  	net_set_timeout_handler(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 bootp_timeout_handler(void)

  {

  	ulong time_taken = get_timer(bootp_start);

  	if (time_taken >= time_taken_max) {

  #ifdef CONFIG_BOOTP_MAY_FAIL

  		char *ethrotate;
  
  		ethrotate = env_get("ethrotate");
  		if ((ethrotate && strcmp(ethrotate, "no") == 0) ||
  		    net_restart_wrap) {
  			puts("
  Retry time exceeded
  ");
  			net_set_state(NETLOOP_FAIL);
  		} else

  #endif

  		{
  			puts("
  Retry time exceeded; starting again
  ");
  			net_start_again();
  		}

  	} else {

  		bootp_timeout *= 2;

  		if (bootp_timeout > 2000)
  			bootp_timeout = 2000;

  		net_set_timeout_handler(bootp_timeout, bootp_timeout_handler);

  		bootp_request();

  	}
  }

  #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)

  static u8 *add_vci(u8 *e)
  {

  	char *vci = NULL;

  	char *env_vci = env_get("bootp_vci");

  #if defined(CONFIG_SPL_BUILD) && defined(CONFIG_SPL_NET_VCI_STRING)

  	vci = CONFIG_SPL_NET_VCI_STRING;

  #elif defined(CONFIG_BOOTP_VCI_STRING)

  	vci = CONFIG_BOOTP_VCI_STRING;

  #endif

  	if (env_vci)
  		vci = env_vci;
  
  	if (vci)
  		put_vci(e, vci);

  	return e;
  }

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

  #if defined(CONFIG_CMD_DHCP)

  static int dhcp_extended(u8 *e, int message_type, struct in_addr server_ip,
  			struct in_addr requested_ip)

  {

  	u8 *start = e;
  	u8 *cnt;

  #ifdef CONFIG_LIB_UUID

  	char *uuid;

  #endif

  	int clientarch = -1;

  #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 (server_ip.s_addr) {
  		int tmp = ntohl(server_ip.s_addr);

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

  	if (requested_ip.s_addr) {
  		int tmp = ntohl(requested_ip.s_addr);

  		*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 = env_get("hostname");

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

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

  		memcpy(e, hostname, hostnamelen);

  		e += hostnamelen;
  	}

  #endif

  #ifdef CONFIG_BOOTP_PXE_CLIENTARCH

  	clientarch = CONFIG_BOOTP_PXE_CLIENTARCH;

  #endif

  	if (env_get("bootp_arch"))

  		clientarch = env_get_ulong("bootp_arch", 16, clientarch);

  
  	if (clientarch > 0) {
  		*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 */

  #ifdef CONFIG_LIB_UUID

  	uuid = env_get("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, UUID_STR_FORMAT_STD);

  			e += 16;
  		} else {
  			printf("Invalid pxeuuid: %s
  ", uuid);
  		}
  	}

  #endif

  	e = add_vci(e);

  #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 bootp_extended(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

  	add_vci(e);

  #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 */

  	/*
  	 * If nothing in list, remove it altogether. Some DHCP servers get
  	 * upset by this minor faux pas and do not respond at all.
  	 */
  	if (e == start + 3) {
  		printf("*** Warning: no DHCP options requested
  ");
  		e -= 3;
  	}

  	return e - start;

  }

  #endif

  void bootp_reset(void)

  {

  	bootp_num_ids = 0;

  	bootp_try = 0;

  	bootp_start = get_timer(0);

  	bootp_timeout = 250;

  }

  void bootp_request(void)

  {

  	uchar *pkt, *iphdr;

  	struct bootp_hdr *bp;

  	int extlen, pktlen, iplen;
  	int eth_hdr_size;

  #ifdef CONFIG_BOOTP_RANDOM_DELAY

  	ulong rand_ms;

  #endif

  	u32 bootp_id;

  	struct in_addr zero_ip;
  	struct in_addr bcast_ip;

  	char *ep;  /* Environment pointer */

  	bootstage_mark_name(BOOTSTAGE_ID_BOOTP_START, "bootp_start");

  #if defined(CONFIG_CMD_DHCP)

  	dhcp_state = INIT;
  #endif

  	ep = env_get("bootpretryperiod");

  	if (ep != NULL)
  		time_taken_max = simple_strtoul(ep, NULL, 10);
  	else
  		time_taken_max = TIMEOUT_MS;

  #ifdef CONFIG_BOOTP_RANDOM_DELAY		/* Random BOOTP delay */

  	if (bootp_try == 0)

  		srand_mac();

  	if (bootp_try <= 2)	/* Start with max 1024 * 1ms */
  		rand_ms = rand() >> (22 - bootp_try);

  	else		/* After 3rd BOOTP request max 8192 * 1ms */
  		rand_ms = rand() >> 19;

  	printf("Random delay: %ld ms...
  ", rand_ms);

  	mdelay(rand_ms);

  #endif	/* CONFIG_BOOTP_RANDOM_DELAY */

  	printf("BOOTP broadcast %d
  ", ++bootp_try);

  	pkt = net_tx_packet;

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

  	eth_hdr_size = net_set_ether(pkt, net_bcast_ethaddr, 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_hdr)); */

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

  	pkt += IP_UDP_HDR_SIZE;

  	bp = (struct bootp_hdr *)pkt;

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

  	/*
  	 * according to RFC1542, should be 0 on first request, secs since
  	 * first request otherwise
  	 */
  	bp->bp_secs = htons(get_timer(bootp_start) / 1000);

  	zero_ip.s_addr = 0;
  	net_write_ip(&bp->bp_ciaddr, zero_ip);
  	net_write_ip(&bp->bp_yiaddr, zero_ip);
  	net_write_ip(&bp->bp_siaddr, zero_ip);
  	net_write_ip(&bp->bp_giaddr, zero_ip);

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

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

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

  #if defined(CONFIG_CMD_DHCP)

  	extlen = dhcp_extended((u8 *)bp->bp_vend, DHCP_DISCOVER, zero_ip,
  			       zero_ip);

  #else

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

  #endif

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

  	 *	plus the current time in ms.

  	 */

  	bootp_id = ((u32)net_ethaddr[2] << 24)
  		| ((u32)net_ethaddr[3] << 16)
  		| ((u32)net_ethaddr[4] << 8)
  		| (u32)net_ethaddr[5];

  	bootp_id += get_timer(0);
  	bootp_id = htonl(bootp_id);
  	bootp_add_id(bootp_id);

  	net_copy_u32(&bp->bp_id, &bootp_id);

  
  	/*
  	 * 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;

  	bcast_ip.s_addr = 0xFFFFFFFFL;
  	net_set_udp_header(iphdr, bcast_ip, PORT_BOOTPS, PORT_BOOTPC, iplen);

  	net_set_timeout_handler(bootp_timeout, bootp_timeout_handler);

  #if defined(CONFIG_CMD_DHCP)

  	dhcp_state = SELECTING;

  	net_set_udp_handler(dhcp_handler);

  #else

  	net_set_udp_handler(bootp_handler);

  #endif

  	net_send_packet(net_tx_packet, pktlen);

  }

  #if defined(CONFIG_CMD_DHCP)

  static void dhcp_process_options(uchar *popt, uchar *end)

  {

  	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 0:
  			oplen = -1; /* Pad omits len byte */
  			break;

  		case 1:

  			net_copy_ip(&net_netmask, (popt + 2));

  			break;

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

  		case 2:		/* Time offset	*/

  			to_ptr = &net_ntp_time_offset;

  			net_copy_u32((u32 *)to_ptr, (u32 *)(popt + 2));

  			net_ntp_time_offset = ntohl(net_ntp_time_offset);

  			break;
  #endif

  		case 3:

  			net_copy_ip(&net_gateway, (popt + 2));

  			break;
  		case 6:

  			net_copy_ip(&net_dns_server, (popt + 2));

  #if defined(CONFIG_BOOTP_DNS2)

  			if (*(popt + 1) > 4)

  				net_copy_ip(&net_dns_server2, (popt + 2 + 4));

  #endif

  			break;
  		case 12:

  			size = truncate_sz("Host Name",

  				sizeof(net_hostname), oplen);
  			memcpy(&net_hostname, popt + 2, size);
  			net_hostname[size] = 0;

  			break;
  		case 15:	/* Ignore Domain Name Option */
  			break;
  		case 17:

  			size = truncate_sz("Root Path",

  				sizeof(net_root_path), oplen);
  			memcpy(&net_root_path, popt + 2, size);
  			net_root_path[size] = 0;

  			break;

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

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

  		case 42:	/* NTP server IP */

  			net_copy_ip(&net_ntp_server, (popt + 2));

  			break;
  #endif

  		case 51:

  			net_copy_u32(&dhcp_leasetime, (u32 *)(popt + 2));

  			break;

  		case 52:
  			dhcp_option_overload = popt[2];
  			break;

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

  			net_copy_ip(&dhcp_server_ip, (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:	/* Bootfile option */

  			if (!net_boot_file_name_explicit) {
  				size = truncate_sz("Bootfile",
  						   sizeof(net_boot_file_name),
  						   oplen);
  				memcpy(&net_boot_file_name, popt + 2, size);
  				net_boot_file_name[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 void dhcp_packet_process_options(struct bootp_hdr *bp)
  {
  	uchar *popt = (uchar *)&bp->bp_vend[4];
  	uchar *end = popt + BOOTP_HDR_SIZE;
  
  	if (net_read_u32((u32 *)&bp->bp_vend[0]) != htonl(BOOTP_VENDOR_MAGIC))
  		return;
  
  	dhcp_option_overload = 0;
  
  	/*
  	 * The 'options' field MUST be interpreted first, 'file' next,
  	 * 'sname' last.
  	 */
  	dhcp_process_options(popt, end);
  
  	if (dhcp_option_overload & OVERLOAD_FILE) {
  		popt = (uchar *)bp->bp_file;
  		end = popt + sizeof(bp->bp_file);
  		dhcp_process_options(popt, end);
  	}
  
  	if (dhcp_option_overload & OVERLOAD_SNAME) {
  		popt = (uchar *)bp->bp_sname;
  		end = popt + sizeof(bp->bp_sname);
  		dhcp_process_options(popt, end);
  	}
  }

  static int dhcp_message_type(unsigned char *popt)

  {

  	if (net_read_u32((u32 *)popt) != htonl(BOOTP_VENDOR_MAGIC))

  		return -1;
  
  	popt += 4;

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

  			return *(popt + 2);

  		if (*popt == 0)	{
  			/* Pad */
  			popt += 1;
  		} else {
  			/* Scan through all options */
  			popt += *(popt + 1) + 2;
  		}

  	}
  	return -1;
  }

  static void dhcp_send_request_packet(struct bootp_hdr *bp_offer)

  {

  	uchar *pkt, *iphdr;

  	struct bootp_hdr *bp;

  	int pktlen, iplen, extlen;

  	int eth_hdr_size;

  	struct in_addr offered_ip;
  	struct in_addr zero_ip;
  	struct in_addr bcast_ip;

  	debug("dhcp_send_request_packet: Sending DHCPREQUEST
  ");

  	pkt = net_tx_packet;

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

  	eth_hdr_size = net_set_ether(pkt, net_bcast_ethaddr, 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_hdr *)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(bootp_start) / 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
  	 */

  	zero_ip.s_addr = 0;
  	net_write_ip(&bp->bp_giaddr, zero_ip);

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

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

  
  	/*
  	 * ID is the id of the OFFER packet
  	 */

  	net_copy_u32(&bp->bp_id, &bp_offer->bp_id);

  
  	/*
  	 * Copy options from OFFER packet if present
  	 */

  
  	/* Copy offered IP into the parameters request list */

  	net_copy_ip(&offered_ip, &bp_offer->bp_yiaddr);
  	extlen = dhcp_extended((u8 *)bp->bp_vend, DHCP_REQUEST,
  		dhcp_server_ip, offered_ip);

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

  	bcast_ip.s_addr = 0xFFFFFFFFL;
  	net_set_udp_header(iphdr, bcast_ip, 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);

  	net_send_packet(net_tx_packet, pktlen);

  }
  
  /*
   *	Handle DHCP received packets.
   */

  static void dhcp_handler(uchar *pkt, unsigned dest, struct in_addr sip,
  			 unsigned src, unsigned len)

  {

  	struct bootp_hdr *bp = (struct bootp_hdr *)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 (check_reply_packet(pkt, dest, src, len))

  		return;

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

  	if (net_read_ip(&bp->bp_yiaddr).s_addr == 0)
  		return;

  	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 */

  			dhcp_packet_process_options(bp);

  			efi_net_set_dhcp_ack(pkt, len);

  			debug("TRANSITIONING TO REQUESTING STATE
  ");

  			dhcp_state = REQUESTING;

  			net_set_timeout_handler(5000, bootp_timeout_handler);

  			dhcp_send_request_packet(bp);

  #ifdef CONFIG_SYS_BOOTFILE_PREFIX

  		}

  #endif	/* CONFIG_SYS_BOOTFILE_PREFIX */

  
  		return;
  		break;
  	case REQUESTING:

  		debug("DHCP State: REQUESTING
  ");

  		if (dhcp_message_type((u8 *)bp->bp_vend) == DHCP_ACK) {

  			dhcp_packet_process_options(bp);

  			/* Store net params from reply */

  			store_net_params(bp);

  			dhcp_state = BOUND;

  			printf("DHCP client bound to address %pI4 (%lu ms)
  ",

  			       &net_ip, get_timer(bootp_start));

  			net_set_timeout_handler(0, (thand_f *)0);

  			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 dhcp_request(void)

  {

  	bootp_request();

  }

  #endif	/* CONFIG_CMD_DHCP */