FirmwarePatch.py 文件源码

def CalSectCrc(data):
        sections = unpack("<I", data[15:15+4])[0]
        ptr = 27

        print "[+]Patching section CRC..."
        for i in range(sections):
                section = data[ptr:ptr+10]
                type, offset, size = unpack("<HII", section)
                # print "0x%04X: at offset 0x%08X, size 0x%08X [ends at 0x%08X]" %\
                #         (type, offset, size, offset+size)
                if type == 0xc002:
                        print "\tUnknown header type C002 ignored..."
                        ptr+=10
                        continue
                section_data = data[offset:offset+size]
                c = (crc32(section_data[:24] + "\0"*4 + section_data[28:], \
                           0xFFFFFFFF)^0xFFFFFFFF) & 0xffffffff
                print "\tCalculated crc: %s" % ("0x%08X" % c)

                section_data = section_data[:24] + pack("<I", c) + section_data[28:]
                data = data[:offset] + section_data + data[offset+size:]

                ptr+=10

        return data