Index: configure
===================================================================
RCS file: /sources/grub/grub/configure,v
retrieving revision 1.114
diff -u -r1.114 configure
--- configure	8 May 2005 02:51:51 -0000	1.114
+++ configure	2 Feb 2006 19:05:10 -0000
@@ -5571,6 +5571,15 @@
   NET_EXTRAFLAGS="$NET_EXTRAFLAGS -DCONFIG_PCI_DIRECT=1"
 fi
 
+# Check whether --enable-dhcpvsi or --disable-dhcpvsi was given.
+if test "${enable_dhcpvsi+set}" = set; then
+  enableval="$enable_dhcpvsi"
+
+fi;
+if test "x$enable_dhcpvsi" = xyes; then
+  NET_EXTRAFLAGS="$NET_EXTRAFLAGS -DINCLUDE_DHCPVSI=1"
+fi
+
 # Check whether --enable-3c509 or --disable-3c509 was given.
 if test "${enable_3c509+set}" = set; then
   enableval="$enable_3c509"
Index: configure.ac
===================================================================
RCS file: /sources/grub/grub/configure.ac,v
retrieving revision 1.9
diff -u -r1.9 configure.ac
--- configure.ac	8 May 2005 02:51:51 -0000	1.9
+++ configure.ac	2 Feb 2006 19:05:10 -0000
@@ -326,6 +326,12 @@
   NET_EXTRAFLAGS="$NET_EXTRAFLAGS -DCONFIG_PCI_DIRECT=1"
 fi
 
+AC_ARG_ENABLE(dhcpvsi,
+  [  --enable-dhcpvsi        enable VSI option for DHCP])
+if test "x$enable_dhcpvsi" = xyes; then
+  NET_EXTRAFLAGS="$NET_EXTRAFLAGS -DINCLUDE_DHCPVSI=1"
+fi
+
 dnl Device drivers.
 AC_ARG_ENABLE(3c509,
   [  --enable-3c509          enable 3Com509 driver])
Index: netboot/README.netboot
===================================================================
RCS file: /sources/grub/grub/netboot/README.netboot,v
retrieving revision 1.7
diff -u -r1.7 README.netboot
--- netboot/README.netboot	2 Jan 2002 21:56:40 -0000	1.7
+++ netboot/README.netboot	2 Feb 2006 19:05:10 -0000
@@ -22,6 +22,10 @@
   the latter is the ``Preboot Execution Environment" format, which is
   used by a PXE ROM. You may buy a PXE ROM from some companies.
 
+--enable-dhcpvsi
+  Forces pxegrub to send a vendor specific DHCP option for all outgoing
+  traffic, and forces it to check all incoming traffic for a VS option.
+
 Here is the information about the device drivers. They are all disabled
 by default, so you must specify configure options to enable drivers you
 want to use. Some drivers have extra per-driver options, so the extra
Index: netboot/main.c
===================================================================
RCS file: /sources/grub/grub/netboot/main.c,v
retrieving revision 1.16
diff -u -r1.16 main.c
--- netboot/main.c	20 May 2004 22:17:27 -0000	1.16
+++ netboot/main.c	2 Feb 2006 19:05:10 -0000
@@ -82,8 +82,17 @@
   RFC2132_MSG_TYPE, 1, DHCPDISCOVER,	
   RFC2132_MAX_SIZE,2,	/* request as much as we can */
   ETH_MAX_MTU / 256, ETH_MAX_MTU % 256,
-  RFC2132_PARAM_LIST, 4, RFC1533_NETMASK, RFC1533_GATEWAY,
+  RFC2132_PARAM_LIST, 
+#ifdef	INCLUDE_DHCPVSI
+  5,
+#else
+  4, 
+#endif
+  RFC1533_NETMASK, RFC1533_GATEWAY,
   RFC1533_HOSTNAME, RFC1533_EXTENSIONPATH
+#ifdef	INCLUDE_DHCPVSI
+  , RFC1533_VENDOR, RFC2132_VENDOR_CLASS_ID,7,'p','x','e','g','r','u','b'
+#endif	/*INCLUDE_DHCPVSI*/
 };
 
 static const unsigned char dhcprequest[] =
@@ -95,14 +104,25 @@
   ETH_MAX_MTU / 256, ETH_MAX_MTU % 256,
   /* request parameters */
   RFC2132_PARAM_LIST,
+#ifdef	INCLUDE_DHCPVSI
+  /* 4 standard + 2 vendortags + 1 VSI tag*/
+  4 + 2 + 1,
+#else
   /* 4 standard + 2 vendortags */
   4 + 2,
+#endif
   /* Standard parameters */
   RFC1533_NETMASK, RFC1533_GATEWAY,
   RFC1533_HOSTNAME, RFC1533_EXTENSIONPATH,
+#ifdef	INCLUDE_DHCPVSI
+  RFC1533_VENDOR,
+#endif
   /* Etherboot vendortags */
   RFC1533_VENDOR_MAGIC,
   RFC1533_VENDOR_CONFIGFILE,
+#ifdef	INCLUDE_DHCPVSI
+  RFC2132_VENDOR_CLASS_ID,7,'p','x','e','g','r','u','b'
+#endif
 };
 
 #endif /* ! NO_DHCP_SUPPORT */
@@ -738,6 +758,11 @@
 int 
 await_reply (int type, int ival, void *ptr, int timeout)
 {
+#ifdef	INCLUDE_DHCPVSI  
+  unsigned int vendi,count;
+  char grubvendorID[] = {0x70,0x78,0x65,0x67,0x72,0x75,0x62,0xFF};
+  unsigned int gvIDsize = (sizeof(grubvendorID)/sizeof(char));
+#endif
   unsigned long time;
   struct iphdr *ip;
   struct udphdr *udp;
@@ -900,6 +925,21 @@
 	      arptable[ARP_CLIENT].ipaddr.s_addr
 		= bootpreply->bp_yiaddr.s_addr;
 #ifndef	NO_DHCP_SUPPORT
+#ifdef	INCLUDE_DHCPVSI   
+          /**Check that DHCP option 43 for magic grubvendorID*/
+          for(vendi=count=0; vendi<(BOOTP_VENDOR_LEN+2-gvIDsize);vendi++) {
+            while(bootpreply->bp_vend[vendi+count]==grubvendorID[count]
+            && count < gvIDsize)
+		      count++;
+            if (count==gvIDsize)
+              break;
+            count=0;
+          }
+		  if (count==0) {
+            etherboot_printf("DHCP did not provide VSI\n");
+            continue;
+          }
+#endif
 	      dhcp_addr.s_addr = bootpreply->bp_yiaddr.s_addr;
 #ifdef DEBUG
 	      etherboot_printf ("dhcp_addr = %@\n", dhcp_addr.s_addr);