Question

我正在尝试使用以下函数进行加密和解密，但是，它会导致填充错误。

如果我将PaddingMode设置为None，则会在日志中返回一些字母字符和随机符号。

我可能会错过设置正确结构的内容，如下所示：

Cipher Rijndael（AES）
块大小128位（16字节）
模式CBC（密码块链接）密钥
MD5哈希密码
IV与密钥相同
数据编码Base64字符
UTF-8编码

任何帮助修复此错误以及确保满足上述结构的任何帮助将不胜感激！感谢

错误

CryptographicException: Bad PKCS7 padding. Invalid length 106.
Mono.Security.Cryptography.SymmetricTransform.ThrowBadPaddingException (PaddingMode padding, Int32 length, Int32 position) (at /Users/builduser/buildslave/monoAndRuntimeClassLibs/build/mcs/class/corlib/Mono.Security.Cryptography/SymmetricTransform.cs:363)
Mono.Security.Cryptography.SymmetricTransform.FinalDecrypt (System.Byte[] inputBuffer, Int32 inputOffset, Int32 inputCount) (at /Users/builduser/buildslave/monoAndRuntimeClassLibs/build/mcs/class/corlib/Mono.Security.Cryptography/SymmetricTransform.cs:515)
Mono.Security.Cryptography.SymmetricTransform.TransformFinalBlock (System.Byte[] inputBuffer, Int32 inputOffset, Int32 inputCount) (at /Users/builduser/buildslave/monoAndRuntimeClassLibs/build/mcs/class/corlib/Mono.Security.Cryptography/SymmetricTransform.cs:554)
System.Security.Cryptography.RijndaelManagedTransform.TransformFinalBlock (System.Byte[] inputBuffer, Int32 inputOffset, Int32 inputCount) (at /Users/builduser/buildslave/monoAndRuntimeClassLibs/build/mcs/class/corlib/System.Security.Cryptography/RijndaelManagedTransform.cs:94)
APIConnector.Decrypt (System.String toDecrypt) (at Assets/APIConnector.cs:85)

我的代码

using UnityEngine;
using System;
using System.Collections;
using System.Collections.Generic;
using System.Security.Cryptography;
using System.Text;
using System.Xml;
using System.IO;

public class APIConnector : MonoBehaviour {

    // Use this for initialization
    void Start () {

        Debug.Log ("Starting API connector");


    }

    // Update is called once per frame
    void Update () {



    }

    static string data;
    string firstName="";
    string password="";

    void OnGUI() {

        firstName = GUILayout.TextField (firstName, GUILayout.Width(300));
        password = GUILayout.TextField (password, GUILayout.Width(300));

        if (GUILayout.Button ("Submit"))
                        submit ();

    }

    //Our functions

    void submit(){

        Debug.Log ("Name is: " + firstName + " encrypted is: " + Encrypt(firstName));
        Debug.Log ("Name is: " + firstName + " decrypted is: " + Decrypt(firstName));

    }


            public static string Encrypt (string toEncrypt)
            {
        byte[] keyArray = UTF8Encoding.UTF8.GetBytes ("SecretPassphrase");
                // 256-AES key
        int numBytes = System.Text.Encoding.UTF8.GetBytes(toEncrypt).Length;
        Debug.Log ("Bytes: " + numBytes);
                byte[] toEncryptArray = UTF8Encoding.UTF8.GetBytes (toEncrypt);
                RijndaelManaged rDel = new RijndaelManaged ();
                rDel.Key = keyArray;
                rDel.BlockSize = 128;
                rDel.Mode = CipherMode.CBC;
                // http://msdn.microsoft.com/en-us/library/system.security.cryptography.ciphermode.aspx
                rDel.Padding = PaddingMode.PKCS7;
                // better lang support
                ICryptoTransform cTransform = rDel.CreateEncryptor ();
                byte[] resultArray = cTransform.TransformFinalBlock (toEncryptArray, 0, toEncryptArray.Length);
                return Convert.ToBase64String (resultArray, 0, resultArray.Length);
            }

            public static string Decrypt (string toDecrypt)
            {
        byte[] keyArray = UTF8Encoding.UTF8.GetBytes ("SecretPassphrase");
                // AES-256 key
        byte[] encryptedData = System.Convert.FromBase64String(toDecrypt);
                //byte[] toEncryptArray = Convert.FromBase64String (toDecrypt);
                RijndaelManaged rDel = new RijndaelManaged ();
                rDel.Key = keyArray;
                rDel.BlockSize = 128;
                rDel.Mode = CipherMode.CBC;
                rDel.IV = rDel.Key;
                // http://msdn.microsoft.com/en-us/library/system.security.cryptography.ciphermode.aspx
                rDel.Padding = PaddingMode.PKCS7;
                // better lang support
                ICryptoTransform cTransform = rDel.CreateDecryptor ();
        byte[] resultArray = cTransform.TransformFinalBlock (encryptedData, 0, encryptedData.Length);
                return UTF8Encoding.UTF8.GetString (resultArray);
            }


}

Answer 1

加密时，您似乎没有设置IV，因此将自动使用随机IV。由于在解密时设置IV（并且它不会与加密期间使用的相同），因此第一个输出块将损坏。如果消息足够短（<1块），则填充也将损坏，可能导致此错误。

与往常一样，我注意到在其他可能的问题中，使用相同的IV作为密钥是不好的做法，使用Encoding.UTF8.GetBytes()进行密钥推导也是如此。

错误的PKCS7填充错误：无效长度106

1 个答案: