View difference between Paste ID: f604e244a and

-
+#!/usr/bin/python
 
 import sys, struct
 
 #VSS_OFFSET = 0x00180048
 #VSS_SIZE = 0x4000 - 0x48
 VSS_OFFSET = 0x000c0048
 VSS_SIZE = 0x3f58
 
 #PATCH_OFFSET = 0x1af
 PATCH_OFFSET = 0xae
 PATCH_VALUE = 0x01
 PATCH_VARIABLE = u"Setup"
 
 def hexdump(s,sep=" "):
 	return sep.join(map(lambda x: "%02x"%ord(x),s))
 
 def ascii(s):
 	s2 = ""
 	for c in s:
 		if ord(c)<0x20 or ord(c)>0x7e:
 			s2 += "."
 		else:
 			s2 += c
 	return s2
 
 def pad(s,c,l):
 	if len(s)<l:
 		s += c * (l-len(s))
 	return s
 
 def chexdump(s,ts=""):
 	for i in range(0,len(s),16):
 		print ts+"%08x  %s  %s  |%s|"%(i,pad(hexdump(s[i:i+8],' ')," ",23),pad(hexdump(s[i+8:i+16],' ')," ",23),pad(ascii(s[i:i+16])," ",16))
 
 def addup(s):
 	if len(s) & 1:
 		s = s + "\x00"
 	sum = 0
 	while len(s):
 		sum += struct.unpack("<H",s[:2])[0]
 		s = s[2:]
 	return sum &0xFFFF
 
 class VAR(object):
 	GLOBAL_VARIABLE = "\x61\xdf\xe4\x8b\xca\x93\xd2\x11\xaa\x0d\x00\xe0\x98\x03\x2b\x8c"
 	def __init__(self, data):
 		hdr = data[:0x20]
 		self.magic, self.status, self.attributes, self.nsize, self.dsize, self.guid = struct.unpack("<HHIII16s", hdr)
 		if self.magic != 0x55aa:
 			raise ValueError("bad magic 0x%x"%self.magic)
 		self.bname = data[0x20:0x20+self.nsize]
 		self.name = ''.join(data[0x20:0x20+self.nsize:2])
 		self.name = self.name.split("\x00")[0]
 		self.value = data[0x20+self.nsize:0x20+self.nsize+self.dsize]
 		self.data = data[:0x20+self.nsize+self.dsize]
 		cdata = data[:0x20] + "\x00\x00" + data[0x20:]
 		fdata = "\xaa\x55\x7f\x00" + cdata[4:0x20+self.nsize+self.dsize]
 	def update(self):
 		self.nsize = len(self.name) * 2 + 2
                 self.dsize = len(self.value)
 		self.data = struct.pack("<HHIII16s", self.magic, self.status, self.attributes, self.nsize, self.dsize, self.guid)
 		self.data += self.name.encode('utf-16le') + "\x00\x00"
 		self.data += self.value
 		fdata = "\xaa\x55\x7f\x00" + self.data[4:0x20+self.nsize+self.dsize]
                 self.data = self.data[:0x20] + self.data[0x20:]
 	def showinfo(self, ts=''):
 		print ts+"Variable %s"%repr(self.name)
 		print ts+" Attributes: 0x%08x"%self.attributes
 		print ts+" Status: 0x%02x"%self.status
 		if self.guid == self.GLOBAL_VARIABLE:
 			print ts+" VendorGUID: EFI_GLOBAL_VARIABLE (%s)"%' '.join('%02x'%ord(c) for c in self.guid)
 		else:
 			print ts+" VendorGUID: %s"%' '.join('%02x'%ord(c) for c in self.guid)
 		print ts+" Value (0x%x bytes):"%(len(self.value))
 		chexdump(self.value, ts+"  ")
 
 print "Loading BIOS..."
 bin = open(sys.argv[1], "rb").read()
 
 print "Loading VSS..."
 vss = bin[VSS_OFFSET:VSS_OFFSET+VSS_SIZE]
 
 if vss[:4] != "$VSS":
 	raise ValueError("Invalid VSS signature")
 
 off = 0x10
 
 found = False
 
 while not found and vss[off:off+2] == "\xaa\x55":
 	var = VAR(vss[off:])
 	if var.name == PATCH_VARIABLE and var.status == 0x7f:
 		found = True
 	else:
 		off += len(var.data)
 
 if not found:
 	#print "Variable not found!"
 	raise ValueError("Variable not found!")
 
 print "Old state:"
 var.showinfo()
 
 var.value = var.value[:PATCH_OFFSET] + chr(PATCH_VALUE) + var.value[PATCH_OFFSET+1:]
 var.update()
 print "Patched state:"
 var = VAR(var.data)
 var.showinfo()
 
 print "Updating VSS..."
 vss = vss[:off] + var.data + vss[off+len(var.data):]
 
 print "Updating BIOS..."
 bin = bin[:VSS_OFFSET] + vss + bin[VSS_OFFSET+VSS_SIZE:]
 
 print "Writing output..."
 ofd = open(sys.argv[2], "wb")
 ofd.write(bin)
 ofd.close()
 
 print "Done"