AES解密decrypt()未产生结果
我遇到了一个问题，我的解密函数无法解密已经加密的文本。没有错误提示，只是返回了一些意想不到的结果。
这个加密函数使用盐值和密码来加密一个文本文件，然后把它保存为一个 .enc 文件。之后我尝试运行我的解密函数，它能识别出盐值、初始化向量（iv）、密码、迭代次数等等，但就是无法正确解密。这里是代码和一个干运行的示例。任何指导或帮助都非常感谢。
加密/解密：
from Crypto import Random
from Crypto.Cipher import AES
from base64 import b64encode, b64decode
from os import urandom
import hashlib
def key_generation(password, salt, iterations):
assert iterations > 0
print "Salt: " + salt, '\n', "Password: " + password
key = password + salt #Combines [password] and [salt] to create a [key]
for i in range(iterations): #Hashes the [key]
key = hashlib.sha256(key).digest() #Using Sha256 it hashes the [key] based on amount of [iterations]
print '\nKey: ' + key #Debug Print
return key
def pad(s):
return s + b"\0" * (AES.block_size - len(s) % AES.block_size)
def encryption(message, password, salt, iterations, key_size=256):
key = key_generation(password, salt, iterations)
message = pad(message)
iv = Random.new().read(AES.block_size)
cipher = AES.new(key, AES.MODE_CBC, iv)
print "Random IV: " + iv
enc = salt + iv + cipher.encrypt(message)
print "Length: " + str(len(enc))
enc = pad(enc)
print "Length: " + str(len(enc))
return enc
def decryption(ciphertext, password, iterations):
salt = ciphertext[0:16]
iv = ciphertext[:AES.block_size]
print len(str(iv))
print len(str(salt))
key = key_generation(password, salt, iterations)
cipher = AES.new(key, AES.MODE_CBC, iv)
plaintext = cipher.decrypt(ciphertext[AES.block_size:])
print "Plaintext: " + plaintext
return plaintext.rstrip(b"\0")
def encrypt_file(file_name, password, salt, iterations):
with open(file_name, 'rb') as fo:
plaintext = fo.read()
print "Text: " + plaintext
enc = encryption(plaintext, password, salt, iterations)
print "Encrypted Contents: " + enc
with open(file_name + ".enc", 'wb') as fo:
fo.write(enc)
def decrypt_file(file_name, password, iterations):
with open(file_name, 'rb') as fo:
ciphertext = fo.read()
print "Cipher'd Text: " + ciphertext
dec = decryption(ciphertext, password, iterations)
with open(file_name[:-4], 'wb') as fo:
fo.write(dec)
encrypt_file('HelloWorld.txt', 'password', 'randomsalt', 64000)
decrypt_file('HelloWorld.txt.enc', 'password', 64000)
干运行：
加密：
Text: }¦—Z“Íd¥çgZw?øÈH™«Nœfra¥)ÊãjnÞª»^}K^Ì„¦ý
×¾Šv“_3w€mG9‚ä¤Å¥žUƯ0£Óy®0²
nrfÖÖ «–‰¯ò
Salt: randomsalt
Password: password
Key: /Îbdﾍ5è!ﾆﾋAﾪv=L*øK/ò)Ü
Random IV: eﾐý1ËÈUÓbIﾜﾴﾑl
Length: 138
Length: 144
Encrypted Contents: randomsalteﾐý1ËÈUÓbIﾜﾴﾑl$֭>oﾘ)<Lﾞy\I!%wÙßÞlﾓÊJt$ﾜ
è Ì-ﾳMﾡ8ﾍ!ﾰܩﾧÆ4ÒO9AÃðO.ä3}ﾍål{ﾇﾋ@ÿËzﾷgDﾪ\éUʼaà8ﾀLﾠMupaÔAﾐﾏX0ﾝﾵi3ﾖ˧cﾧ;ﾫÛo
解密：
Cipher'd Text: randomsalteﾐý1ËÈUÓbIﾜﾴﾑl$֭>oﾘ)<Lﾞy\I!%wÙßÞlﾓÊJt$ﾜ
è Ì-ﾳMﾡ8ﾍ!ﾰܩﾧÆ4ÒO9AÃðO.ä3}ﾍål{ﾇﾋ@ÿËzﾷgDﾪ\éUʼaà8ﾀLﾠMupaÔAﾐﾏX0ﾝﾵi3ﾖ˧cﾧ;ﾫÛo
16
16
Salt: randomsalteﾐý1Ë
Password: password
Key: 1ÜA !TzxGÑ`wß~|º‹|¡(—ª-%òÇŒÖ
Plaintext: Rﾈ*SﾶÕñÛ.
t-Îﾃýﾄ͛'úﾺSﾀ&2ﾮæﾏéﾇﾻýýﾽtçØÉe?×ûìrﾓﾳÞcﾺﾲ×_Kﾒ
ﾺÀ~ä'ﾩ,ﾵ-Èﾡt&gSð:WÕ|
ﾒ^ﾘøﾧ]ﾉﾔÏYvísgl/ﾯﾚﾎ*`\ﾰåﾸŴÇlﾋÓ!Â`ﾟ
1 个回答
0
所以请把东西以十六进制的形式打印出来。这样你就能清楚地看到，在解密的过程中，盐值和初始化向量（IV）确实是重叠的。在你的代码中，你还假设了一个和实际提供的盐值长度不同的值。
from Crypto import Random
from Crypto.Cipher import AES
from base64 import b64encode, b64decode
from os import urandom
import hashlib
import binascii
def key_generation(password, salt, iterations):
assert iterations > 0
print "Salt: " + tohex(salt), '\n', "Password: " + password
key = password + salt #Combines [password] and [salt] to create a [key]
for i in range(iterations): #Hashes the [key]
key = hashlib.sha256(key).digest() #Using Sha256 it hashes the [key] based on amount of [iterations]
return key
def pad(s):
return s + b"\0" * (AES.block_size - len(s) % AES.block_size)
def encryption(message, password, salt, iterations, key_size=256):
print " === ENCRYPTION === "
key = key_generation(password, salt, iterations)
print "Key: " + tohex(key)
message = pad(message)
iv = Random.new().read(AES.block_size)
cipher = AES.new(key, AES.MODE_CBC, iv)
print "Random IV: " + tohex(iv)
enc = salt + iv + cipher.encrypt(message)
return enc
def decryption(ciphertext, password, iterations):
print " === DECRYPTION === "
salt = ciphertext[0:10]
iv = ciphertext[10:10+AES.block_size]
print "Random IV: " + tohex(iv)
key = key_generation(password, salt, iterations)
print "Key: " + tohex(key)
cipher = AES.new(key, AES.MODE_CBC, iv)
plaintext = cipher.decrypt(ciphertext[10+AES.block_size:])
print "Plaintext: " + plaintext
return plaintext.rstrip(b"\0")
def encrypt_file(file_name, password, salt, iterations):
with open(file_name, 'rb') as fo:
plaintext = fo.read()
print "Text: " + plaintext
enc = encryption(plaintext, password, salt, iterations)
print "Encrypted Contents: " + enc
with open(file_name + ".enc", 'wb') as fo:
fo.write(enc)
def decrypt_file(file_name, password, iterations):
with open(file_name, 'rb') as fo:
ciphertext = fo.read()
print "Cipher'd Text: " + ciphertext
dec = decryption(ciphertext, password, iterations)
with open(file_name + ".dec", 'wb') as fo:
fo.write(dec)
def tohex(data):
return binascii.hexlify(data)
encrypt_file('HelloWorld.txt', 'password', 'randomsalt', 64000)
decrypt_file('HelloWorld.txt.enc', 'password', 64000)