Python PyCrypto Cyphertext即使使用一个字符的数据，长度也不正确

我想加密/解密包含在.csv文件中的一组数据。 我使用以下代码生成RSA公钥/私钥：

import Crypto
from Crypto.PublicKey import RSA

key = RSA.generate(2048)

k = key.exportKey('PEM')
p = key.publickey().exportKey('PEM')

with open('private.pem', 'w') as kf:
    kf.write(k.decode())
    kf.close()

with open('public.pem', 'w') as pf:
    pf.write(p.decode())
    pf.close()

with open('private.pem','r') as fk:
    priv = fk.read()
    fk.close()

with open('public.pem','r') as fp:
    pub = fp.read()
    fp.close()

privat = RSA.importKey(priv)
public = RSA.importKey(pub)

if key == privat:
    print('Private key has been successfuly write')
if key.publickey() == public:
    print('Public key has been successfuly write')

然后我用这段代码加密，没有任何问题：

import Crypto
from Crypto.PublicKey import RSA
from Crypto.Cipher import PKCS1_OAEP

with open('public.pem','r') as fp:
    pub = fp.read()
    fp.close()

public = RSA.importKey(pub)

#stockage du fichier dans une variable rep
fichier = open('test.csv', 'r')
rep = fichier.read()
fichier.close()

#eliminations des spaces
rep = rep.replace(' ', '')

#encodage pour type bytes
rep = rep.encode()

#decoupage en mot de 10 chars
rep = [rep[i:i+10] for i in range(0, len(rep), 10)]

cipher = PKCS1_OAEP.new(public)

fichier2 = open('encrypted.csv', 'a')
for i in rep:
    encrypted_line = cipher.encrypt(i)
    fichier2.write(str(encrypted_line))
    fichier2.write('\n')

fichier2.close()

我可以通过修改此行来修改数据的分离方式：

rep=[rep[i:i+n]表示范围内的i（0，len（rep），n）]

这行按n个字符组分隔我的数据

这里是我解密数据的代码，它引发：

ValueError:长度不正确的密文

---

我试图对一个示例文件进行编码，但它引发了这个错误。然后我尝试直接在Python解释器上处理一个只包含一个字符的文件。加密工作正常，但解密失败，错误与上述相同。

代码的主要问题是使用换行符来分隔加密数据块。加密数据可能已经包含换行符，因此尝试将加密数据拆分为行可能会产生部分块，这将导致解密时出现的

ValueError

第二个问题是加密文件是以文本模式打开的。处理加密数据时，以二进制模式打开文件。加密的

字节

不太可能解码为

str

，因此使用文本模式将导致编码或解码错误

此版本的代码适用于：

import functools

from Crypto.PublicKey import RSA 
from Crypto.Cipher import PKCS1_OAEP

if __name__ == '__main__':

    # Encrypt

    with open('public.pem', 'r') as fp: 
        pub = fp.read()
        fp.close()

    public = RSA.importKey(pub)

    # tockage du fichier dans une variable rep
    with open('test.csv', 'r') as fichier:
        rep = fichier.read()

    # liminations des spaces
    rep = rep.replace(' ', '') 

    # ncodage pour type bytes
    rep = rep.encode()

    cipher = PKCS1_OAEP.new(public)

    # decoupage en mot de 10 chars
    rep = [rep[i:i+10] for i in range(0, len(rep), 10)]

    # Open the file in binary mode so we can write bytes.
    with open('encrypted.csv', 'wb') as fichier2:
        for i in rep:
            fichier2.write(cipher.encrypt(i))

    # Decrypt
    with open('private.pem', 'r') as fk: 
        priv = fk.read()

    private = RSA.importKey(priv)

    CHUNK_SIZE = 256 
    # Open the file in binary mode so we can read bytes.
    with open('encrypted.csv', 'rb') as fichier:
        # Create an iterator that will return chunks of the correct size.
        chunker = iter(functools.partial(fichier.read, CHUNK_SIZE), b'')
        rep = list(chunker)

    cipher = PKCS1_OAEP.new(private)

    with open('decrypted.csv', 'w') as fichier2:
        for i in rep:
            decrypted_line = cipher.decrypt(i)
            fichier2.write(decrypted_line.decode())

---

这段代码不是在换行符上拆分加密数据，而是以256字节的块从文件中读取，因为加密过程似乎为每个输入块生成256字节。我不是密码学家，所以这可能并不总是正确的。在这种情况下，最好一步加密（或解密）所有数据。

谢谢，我不知道functools.partial与iter的结合使用。我不认为我的文件是以“字节”模式打开的。事实上，它也必须改变数据。如果有人想使用此代码，请小心，如果不在范围（0，len（rep），10）]中的i使用行

rep=[rep[i:i+10]，

，则在这种情况下必须强制rep的类型，否则在最终循环中将其解释为int。

import functools

from Crypto.PublicKey import RSA 
from Crypto.Cipher import PKCS1_OAEP

if __name__ == '__main__':

    # Encrypt

    with open('public.pem', 'r') as fp: 
        pub = fp.read()
        fp.close()

    public = RSA.importKey(pub)

    # tockage du fichier dans une variable rep
    with open('test.csv', 'r') as fichier:
        rep = fichier.read()

    # liminations des spaces
    rep = rep.replace(' ', '') 

    # ncodage pour type bytes
    rep = rep.encode()

    cipher = PKCS1_OAEP.new(public)

    # decoupage en mot de 10 chars
    rep = [rep[i:i+10] for i in range(0, len(rep), 10)]

    # Open the file in binary mode so we can write bytes.
    with open('encrypted.csv', 'wb') as fichier2:
        for i in rep:
            fichier2.write(cipher.encrypt(i))

    # Decrypt
    with open('private.pem', 'r') as fk: 
        priv = fk.read()

    private = RSA.importKey(priv)

    CHUNK_SIZE = 256 
    # Open the file in binary mode so we can read bytes.
    with open('encrypted.csv', 'rb') as fichier:
        # Create an iterator that will return chunks of the correct size.
        chunker = iter(functools.partial(fichier.read, CHUNK_SIZE), b'')
        rep = list(chunker)

    cipher = PKCS1_OAEP.new(private)

    with open('decrypted.csv', 'w') as fichier2:
        for i in rep:
            decrypted_line = cipher.decrypt(i)
            fichier2.write(decrypted_line.decode())