Question

我正在尝试将下面的程序翻译成Python。最后，Python代码应该生成与Perl变体相同的密码短语输出。

#!/usr/bin/env perl
use Crypt::CBC;

my $key = 'key to the gates'; 
my $cipher = Crypt::CBC->new(
    -key    => $key,
    -cipher => 'Blowfish',
    -salt => '12341234'  
);
my $pass_phrase = "secret text";
print $cipher->encrypt_hex($pass_phrase),"\n";
print unpack('H*', $cipher->key()), "\n";
print unpack('H*', $cipher->iv()), "\n";
print unpack('H*', $cipher->salt()), "\n";
print unpack('H*', $cipher->keysize()), "\n";

#output:
#pass:53616c7465645f5f31323334313233344c0ad60f0eb9fdffc46b5cc02d76d473 <- hex enc "Salted__12341234<gibberish>"
#key:031f2cc96d063cf836ce42c77a8a3d25bdd959659d00a892a02b13930e92f47c82a7054256be4a0f1b3771bd36c07fe3ea4f6900f8ddebe5
#iv:f4d50b2385a2a996
#salt:3132333431323334
#keysize:3536

下面是我的python代码，而不是成功解密，但加密失败。 perl密码的成功解密主要用于验证输入参数。（从perl直接采取IV并删除Crypt :: CBC在解密之前添加了16个盐的焦点使其工作，SO上的各种帖子帮助了我......）。

然后是尝试加密passhphrase并生成与perl相同的输出失败。我想我只需要使用经过验证的输入参数的正确组合来使其工作......也许盐应该填充？或填充一般是错的？或者iv输入不应该是己烷化的？（它需要8个字符..）

感谢任何输入！

!/usr/bin/env python
from Crypto.Cipher import Blowfish
from binascii import hexlify, unhexlify
from struct import pack
import base64

# working decryption
passphrase =  unhexlify("53616c7465645f5f31323334313233344c0ad60f0eb9fdffc46b5cc02d76d473"[32:])
key = unhexlify("031f2cc96d063cf836ce42c77a8a3d25bdd959659d00a892a02b13930e92f47c82a7054256be4a0f1b3771bd36c07fe3ea4f6900f8ddebe5")
iv  = unhexlify('f4d50b2385a2a996')
num_padding = ord(Blowfish.new(key, Blowfish.MODE_CBC, iv).decrypt(passphrase)[-1])
print Blowfish.new(key, Blowfish.MODE_CBC, iv).decrypt(passphrase)[:(-1*num_padding)]

# --- non working encryption!
passphrase2 = "secret text"
key2 = 'key to the gates'
iv2  = unhexlify('f4d50b2385a2a996')
plength = Blowfish.block_size - len(passphrase2) % Blowfish.block_size
padding = [plength] * plength
pad_str = passphrase2 + pack('b' * plength, *padding)
cipher = Blowfish.new(key2, Blowfish.MODE_CBC, iv2)
print hexlify("Salted__12341234"+cipher.encrypt(pad_str))

#output:
#secret text
#53616c7465645f5f31323334313233346aa3f2169677cbf282b1330b46da3114

Answer 1

我想你不应该回答你自己的问题，但我还是留在这里:) 我想在原始代码中填充可能不合适，不太确定。这次我使用了很好的＆＃34; Padding＆＃34; lib https://pypi.python.org/pypi/Padding

from Crypto.Cipher import Blowfish
from binascii import hexlify, unhexlify
import Padding 

class BlowFishCipher:
    def __init__( self, key,iv,salt ):
    self.key = unhexlify(key)
    self.iv = unhexlify(iv)
    self.salt = unhexlify(salt)
def encrypt( self, raw ):
    raw = Padding.appendPadding(raw, BS)
    cipher = Blowfish.new( self.key, Blowfish.MODE_CBC, self.iv )
    return hexlify("Salted__"+self.salt+cipher.encrypt(raw))
def decrypt( self, enc):
    enc = unhexlify(enc)
    cipher = Blowfish.new(self.key, Blowfish.MODE_CBC, self.iv )
    return Padding.removePadding(cipher.decrypt( enc), BS)

if __name__== "__main__":
    BS = Blowfish.block_size
    key_perl = "031f2cc96d063cf836ce42c77a8a3d25bdd959659d00a892a02b13930e92f47c82a7054256be4a0f1b3771bd36c07fe3ea4f6900f8ddebe5"
    iv_perl = "f4d50b2385a2a996"
    salt_perl= "3132333431323334"
    passphrase_perl = "53616c7465645f5f31323334313233344c0ad60f0eb9fdffc46b5cc02d76d473"
    # remove "Salted__12341234" from passhphrase_perl by [32:]  
    passphrase = passphrase_perl[32:]
    decryptor = BlowFishCipher(key_perl,iv_perl,salt_perl)
    plaintext = decryptor.decrypt(passphrase)
    print "decrypted        {:>70}".format(plaintext)
    ciphertext = "secret text"
    encodedtext = decryptor.encrypt(ciphertext)
    print "encrypted pyhton {:>70}".format(encodedtext)
    print "encrypted perl   {:>70}".format(passphrase_perl)

解密的秘密文本

加密pyhton 53616c7465645f5f31323334313233344c0ad60f0eb9fdffc46b5cc02d76d473

加密perl 53616c7465645f5f31323334313233344c0ad60f0eb9fdffc46b5cc02d76d473

转换Crypt时的加密问题：CBC示例从Perl转换为Python（Blowfish）

1 个答案: