用户对问题“如何使用头文件签名(幻数)检查文件类型？”的回答

如何使用头文件签名(幻数)检查文件类型？

magic_numbers = {'png': bytes([0x89, 0x50, 0x4E, 0x47, 0x0D, 0x0A, 0x1A, 0x0A]),
                 'jpg': bytes([0xFF, 0xD8, 0xFF, 0xE0]),
                 #*********************#
                 'doc': bytes([0xD0, 0xCF, 0x11, 0xE0, 0xA1, 0xB1, 0x1A, 0xE1]),
                 'xls': bytes([0xD0, 0xCF, 0x11, 0xE0, 0xA1, 0xB1, 0x1A, 0xE1]),
                 'ppt': bytes([0xD0, 0xCF, 0x11, 0xE0, 0xA1, 0xB1, 0x1A, 0xE1]),
                 #*********************#
                 'docx': bytes([0x50, 0x4B, 0x03, 0x04, 0x14, 0x00, 0x06, 0x00]),
                 'xlsx': bytes([0x50, 0x4B, 0x03, 0x04, 0x14, 0x00, 0x06, 0x00]),
                 'pptx': bytes([0x50, 0x4B, 0x03, 0x04, 0x14, 0x00, 0x06, 0x00]),
                 #*********************#
                 'pdf': bytes([0x25, 0x50, 0x44, 0x46]),
                 #*********************#
                 'dll': bytes([0x4D, 0x5A, 0x90, 0x00]),
                 'exe': bytes([0x4D, 0x5A]),
max_read_size = max(len(m) for m in magic_numbers.values()) 
with open('file.pdf', 'rb') as fd:
    file_head = fd.read(max_read_size)
if file_head.startswith(magic_numbers['pdf']):
    print("It's a PDF File")
else:
    print("It's not a PDF file")

if file_head.startswith(magic_numbers['pdf']):
    print("It's a PDF File")
else:
    print("It's not a PDF file")

for ext in magic_numbers:
    if file_head.startswith(magic_numbers[ext]):
        print("It's a {} File".format(ext))

ext = filename.rsplit('.', 1)[-1]

if ext in magic_numbers:
    if file_head.startswith(magic_numbers[ext]):
        return ext

ext = filename.rsplit('.', 1)[-1]
if ext in magic_numbers:
    if file_head.startswith(magic_numbers[ext]):
        return ext

如何使用头文件签名(幻数)检查文件类型？

1 个回答