使用/etc/shadow中的哈希密码加密文件

Question

希望使用/etc/shadow中的哈希密码来加密文件。尝试使用Python2.7。现有代码正在使用Crypto.Cipher/散列但要求用户输入密码。从我能读到的关于spwd的内容来看，我可以验证输入的密码是否与哈希值正确匹配，但是我想使用哈希值，根本不要求用户输入密码。你知道吗

from Crypto.Hash import SHA256
from Crypto.Cipher import AES
import os, random, sys

from os import path

def encrypt(key, filename, outFile):
    chunksize = 64 * 1024
    filesize = str(os.path.getsize(filename)).zfill(16)
    IV = ''

    for i in range(16):
            IV += chr(random.randint(0, 0xFF))

    encryptor = AES.new(key, AES.MODE_CBC, IV)

    with open(filename, "rb") as infile:
        with open(outFile, "wb") as outfile:
            outfile.write(filesize)
            outfile.write(IV)
            while True:
                    chunk = infile.read(chunksize)

                    if len(chunk) == 0:
                            break

                    elif len(chunk) % 16 !=0:
                            chunk += ' ' *  (16 - (len(chunk) % 16))

                    outfile.write(encryptor.encrypt(chunk))

def decrypt(key, filename, outFile):
    chunksize = 64 * 1024

    with open(filename, "rb") as infile:
            filesize = infile.read(16)
            IV = infile.read(16)

            decryptor = AES.new(key, AES.MODE_CBC, IV)

            with open(outFile, "wb") as outfile:
                    while True:
                            chunk = infile.read(chunksize)
                            if len(chunk) == 0:
                                    break

                            outfile.write(decryptor.decrypt(chunk))

                    outfile.truncate(int(filesize))

BASE_PATH = path.dirname(path.abspath(__file__))

choice = raw_input("Do you want to (E)ncrypt or (D)ecrypt? ")
encFiles = os.path.join(BASE_PATH, 'your_file_name') 

typed_out_file = raw_input('Enter out file_name: ')
outFile = os.path.join(BASE_PATH, typed_out_file) 
password = raw_input("Enter the password: ")  


if choice == "E":

    if os.path.basename(encFiles).startswith("(encrypted)"):
            print "%s is already encrypted" %str(Tfiles)
            pass

    elif encFiles == os.path.join(os.getcwd(), sys.argv[0]):
            pass 
    else:
            encrypt(SHA256.new(password).digest(), str(encFiles), outFile)
            print "Done encrypting %s" %str(encFiles)
            os.remove(encFiles)


elif choice == "D":

    filename = raw_input("Enter the filename to decrypt: ")
    out_file = raw_input("Enter the new filename: ")

    decrypt(SHA256.new(password).digest(), filename, out_file)
    print "Done decrypting %s" %filename
    os.remove(filename)

else:
    print "Please choose a valid command."
    sys.exit()