AES-256-CBC坏解密

Question

第1步：使用pbkdf2

创建密钥

var key = crypto.pbkdf2Sync('prancypoodle', 'sherylcrowe', 10000, 32, 'sha512');

使用密码prancy poodle创建一个密钥，将其加密sherylcrowe，迭代10,000次，输出一个32字节长的密钥（AES-256-CBC需要该长度）。

第2步：加密某些内容

var cipher = crypto.createCipheriv('aes-256-cbc', key, 'dogsarefun'.toString("binary"));

var crypted = cipher.update('wherearemysocks?');
crypted = Buffer.concat([crypted, cipher.final()]);

第3步：解密＆amp;失败

var decipher = crypto.createDecipheriv('aes-256-cbc', key, 'dogsarefun'.toString('binary'));

var decrypted = decipher.update(crypted);
decrypted = Buffer.concat([decrypted, decipher.final()]);
Error: error:06065064:digital envelope routines:EVP_DecryptFinal_ex:bad decrypt
    at Error (native)
    at Decipher.Cipher.final (crypto.js:150:26)
    at repl:1:48
    at REPLServer.defaultEval (repl.js:272:27)
    at bound (domain.js:280:14)
    at REPLServer.runBound [as eval] (domain.js:293:12)
    at REPLServer.<anonymous> (repl.js:441:10)
    at emitOne (events.js:101:20)
    at REPLServer.emit (events.js:188:7)
    at REPLServer.Interface._onLine (readline.js:219:10)

我做错了什么？这似乎是对的，但是错了。

Answer 1

您需要为CBC模式提供IV，它需要是块大小（AES为16字节）。 ＆＃39; dogsarefun＆＃39;只有10个字节，所以剩余的字节是未指定的，可能（可能是）垃圾。

由于PKCS填充是默认设置并且使用了CBC模式，因此错误的IV将导致解密时填充错误，可能是错误：例程：EVP_DecryptFinal_ex：bad decrypt 。

P.S。当心：这是猫所用的互联网。

Answer 2

您需要使用createDecipheriv函数进行解密，并且您的IV必须为16个字符。

示例：

var crypto = require('crypto');
var buffer = require('buffer');

var key = crypto.pbkdf2Sync('prancypoodle', 'sherylcrowe', 10000, 32, 'sha512');

// Initialization vector must be 16 characters.
var cipher = crypto.createCipheriv('aes-256-cbc', key,
  new Buffer('1234567812345678', 'binary'));

var crypted = cipher.update('wherearemysocks?');
console.log('Encrypted: %s', crypted);
crypted = Buffer.concat([crypted, cipher.final()]);
// Again, IV must be 16 characters.
var decipher = crypto.createDecipheriv('aes-256-cbc', key,
  new Buffer('1234567812345678', 'binary'));

var decrypted = decipher.update(crypted);
console.log('Decrypted: %s', decrypted);

输出：

Encrypted: #�j���(����
Decrypted: wherearemysocks?