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	/* CONFIG_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;#ifdef 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_SIZE) >> 16;	*e++ = (576 - 312 + OPT_SIZE) & 0xff;#endif /* CONFIG_CMD_DHCP */#ifdef (CONFIG_BOOTP_MASK & CONFIG_BOOTP_SUBNETMASK)	*e++ = 1;		/* Subnet mask request */	*e++ = 4;	e   += 4;#endif#ifdef (CONFIG_BOOTP_MASK & CONFIG_BOOTP_GATEWAY)	*e++ = 3;		/* Default gateway request */	*e++ = 4;	e   += 4;#endif#ifdef (CONFIG_BOOTP_MASK & CONFIG_BOOTP_DNS)	*e++ = 6;		/* Domain Name Server */	*e++ = 4;	e   += 4;#endif#ifdef (CONFIG_BOOTP_MASK & CONFIG_BOOTP_HOSTNAME)	*e++ = 12;		/* Host name request */	*e++ = 32;	e   += 32;#endif#ifdef (CONFIG_BOOTP_MASK & CONFIG_BOOTP_BOOTFILESIZE)	*e++ = 13;		/* Boot file size */	*e++ = 2;	e   += 2;#endif#ifdef (CONFIG_BOOTP_MASK & CONFIG_BOOTP_BOOTPATH)	*e++ = 17;		/* Boot path */	*e++ = 32;	e   += 32;#endif#ifdef (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	/* CONFIG_CMD_DHCP */voidBootpRequest (void){	volatile uchar *pkt, *iphdr;	Bootp_t *bp;	int ext_len, pktlen, iplen;#ifdef CONFIG_CMD_DHCP	dhcp_state = INIT;#endif	printk("BOOTP broadcast %d\n", ++BootpTry);	pkt = NetTxPacket;	memset ((void*)pkt, 0, PKTSIZE);	pkt += NetSetEther(pkt, NetBcastAddr, PROT_IP);	/*	 * 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 */#ifdef CONFIG_CMD_DHCP	ext_len = DhcpExtended(bp->bp_vend, DHCP_DISCOVER, 0, 0);#else	ext_len = BootpExtended(bp->bp_vend);#endif	/* CONFIG_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);#ifdef CONFIG_CMD_DHCP	dhcp_state = SELECTING;	NetSetHandler(DhcpHandler);#else	NetSetHandler(BootpHandler);#endif	/* CONFIG_CMD_DHCP */	NetSendPacket(NetTxPacket, pktlen);}#ifdef  CONFIG_CMD_DHCPstatic 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));#ifdef (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:#ifdef (CONFIG_BOOTP_MASK & CONFIG_BOOTP_VENDOREX)			if (dhcp_vendorex_proc (popt))				break;#endif			printk ("*** 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);	pkt += NetSetEther(pkt, NetBcastAddr, PROT_IP);	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 voidDhcpHandler(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;			printk("DHCP client bound to address ");			print_IPaddr(NetOurIP);			printk("\n");			/* Obey the 'autoload' setting */			TftpStart();			return;		}		break;	default:		printk("DHCP: INVALID STATE\n");		break;	}}void DhcpRequest(void){	BootpRequest();}#endif	/* CONFIG_CMD_DHCP */