Rfc2898DeriveBytes解密如何通過java實現

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原文 Rfc2898DeriveBytes解密如何通過java實現

這個找了半天，還是不太懂，密碼一點不懂，直接上來問了Rfc2898DeriveBytes對應的是PBKDF2WithHmacSHA1，Rfc2898DeriveBytes預設的迭代次數為1000，剩下的不知道了
以下為C#代碼C# code        public byte[] DecryptData(byte[] data)        {            AesManaged managed = null;            MemoryStream stream = null;            CryptoStream stream2 = null;            try            {                Rfc2898DeriveBytes bytes = new Rfc2898DeriveBytes(this.fPassword, this.Salt);                managed = new AesManaged();                managed.set_Key(bytes.GetBytes(managed.get_KeySize() / 8));                managed.set_IV(bytes.GetBytes(managed.get_BlockSize() / 8));                stream = new MemoryStream();                stream2 = new CryptoStream(stream, managed.CreateDecryptor(), 1);                stream2.Write(data, 0, data.Length);                stream2.FlushFinalBlock();                return stream.ToArray();            }            catch            {                return data;            }        }通過以下代碼無法實現解密Java code        public byte[] dePBE(byte[] data){        try {            char[] password = this.fPassword.toCharArray();            byte[] salt = this.fSalt;             KeySpec spec = new PBEKeySpec(password,salt,1000,128);            SecretKeyFactory factory = SecretKeyFactory.getInstance("PBKDF2WithHmacSHA1");            SecretKey tmp = factory.generateSecret(spec);            SecretKey secret = new SecretKeySpec(tmp.getEncoded(), "AES");             Cipher cipher = Cipher.getInstance("AES/CBC/PKCS5Padding");            cipher.init(Cipher.DECRYPT_MODE, secret, new IvParameterSpec(new byte[cipher.getBlockSize()]));            byte[] ciphertext = cipher.doFinal(data);            return ciphertext;        }catch (Exception e) {                e.printStackTrace();            return null;        }    }

java解決方案：

找到一個複刻的Rfc2898DeriveBytes類
http://www.itstrike.cn/Question/fc038543-6a4e-4796-8333-6b1c1b5cce12.html

import java.io.UnsupportedEncodingException;import java.security.InvalidKeyException;import java.security.NoSuchAlgorithmException;import javax.crypto.Mac;import javax.crypto.spec.SecretKeySpec; /** * RFC 2898 password derivation compatible with .NET Rfc2898DeriveBytes class.  */public class Rfc2898DeriveBytes {     private Mac _hmacSha1;    private byte[] _salt;    private int _iterationCount;     private byte[] _buffer = new byte[20];    private int _bufferStartIndex = 0;    private int _bufferEndIndex = 0;    private int _block = 1;      /**     * Creates new instance.     * @param password The password used to derive the key.     * @param salt The key salt used to derive the key.     * @param iterations The number of iterations for the operation.     * @throws NoSuchAlgorithmException HmacSHA1 algorithm cannot be found.     * @throws InvalidKeyException Salt must be 8 bytes or more. -or- Password cannot be null.     */    public Rfc2898DeriveBytes(byte[] password, byte[] salt, int iterations) throws NoSuchAlgorithmException, InvalidKeyException {        if ((salt == null) || (salt.length < 8)) { throw new InvalidKeyException("Salt must be 8 bytes or more."); }        if (password == null) { throw new InvalidKeyException("Password cannot be null."); }        this._salt = salt;        this._iterationCount = iterations;        this._hmacSha1 = Mac.getInstance("HmacSHA1");        this._hmacSha1.init(new SecretKeySpec(password, "HmacSHA1"));    }     /**     * Creates new instance.     * @param password The password used to derive the key.     * @param salt The key salt used to derive the key.     * @param iterations The number of iterations for the operation.     * @throws NoSuchAlgorithmException HmacSHA1 algorithm cannot be found.     * @throws InvalidKeyException Salt must be 8 bytes or more. -or- Password cannot be null.     * @throws UnsupportedEncodingException UTF-8 encoding is not supported.      */    public Rfc2898DeriveBytes(String password, byte[] salt, int iterations) throws InvalidKeyException, NoSuchAlgorithmException, UnsupportedEncodingException  {        this(password.getBytes("UTF8"), salt, iterations);    }     /**     * Creates new instance.     * @param password The password used to derive the key.     * @param salt The key salt used to derive the key.     * @throws NoSuchAlgorithmException HmacSHA1 algorithm cannot be found.     * @throws InvalidKeyException Salt must be 8 bytes or more. -or- Password cannot be null.     * @throws UnsupportedEncodingException UTF-8 encoding is not supported.      */    public Rfc2898DeriveBytes(String password, byte[] salt) throws NoSuchAlgorithmException, InvalidKeyException, UnsupportedEncodingException {        this(password, salt, 0x3e8);    }      /**     * Returns a pseudo-random key from a password, salt and iteration count.     * @param count Number of bytes to return.     * @return Byte array.     */    public byte[] getBytes(int count) {        byte[] result = new byte[count];        int resultOffset = 0;        int bufferCount = this._bufferEndIndex - this._bufferStartIndex;         if (bufferCount > 0) { //if there is some data in buffer            if (count < bufferCount) { //if there is enough data in buffer                System.arraycopy(this._buffer, this._bufferStartIndex, result, 0, count);                this._bufferStartIndex += count;                return result;            }            System.arraycopy(this._buffer, this._bufferStartIndex, result, 0, bufferCount);            this._bufferStartIndex = this._bufferEndIndex = 0;            resultOffset += bufferCount;        }         while (resultOffset < count) {            int needCount = count - resultOffset;            this._buffer = this.func();            if (needCount > 20) { //we one (or more) additional passes                System.arraycopy(this._buffer, 0, result, resultOffset, 20);                resultOffset += 20;            } else {                System.arraycopy(this._buffer, 0, result, resultOffset, needCount);                this._bufferStartIndex = needCount;                this._bufferEndIndex = 20;                return result;            }        }        return result;    }      private byte[] func() {        this._hmacSha1.update(this._salt, 0, this._salt.length);        byte[] tempHash = this._hmacSha1.doFinal(getBytesFromInt(this._block));         this._hmacSha1.reset();        byte[] finalHash = tempHash;        for (int i = 2; i <= this._iterationCount; i++) {            tempHash = this._hmacSha1.doFinal(tempHash);            for (int j = 0; j < 20; j++) {                finalHash[j] = (byte)(finalHash[j] ^ tempHash[j]);            }        }        if (this._block == 2147483647) {            this._block = -2147483648;        } else {            this._block += 1;        }         return finalHash;    }     private static byte[] getBytesFromInt(int i) {        return new byte[] { (byte)(i >>> 24), (byte)(i >>> 16), (byte)(i >>> 8), (byte)i };    } }

只要這樣就可可以解決了Java codepublic byte[] deRfc2898DeriveBytes(byte[] data,String fPassword,byte[] fSalt){    Rfc2898DeriveBytes keyGenerator = null;    try {        keyGenerator = new Rfc2898DeriveBytes(fPassword, fSalt, 1000);    }    catch (InvalidKeyException e1) {         e1.printStackTrace();    } catch (NoSuchAlgorithmException e1) {        e1.printStackTrace();    } catch (UnsupportedEncodingException e1) {        e1.printStackTrace();    }     //Log.i("key = ", decodeUTF8(keyGenerator.getBytes(16)));         byte[] bKey = keyGenerator.getBytes(32);    byte[] bIv = keyGenerator.getBytes(16);         try {        SecretKeySpec sekey = new SecretKeySpec(bKey, "AES");        AlgorithmParameterSpec param = new IvParameterSpec(bIv);                 Cipher cipher = Cipher.getInstance("AES/CBC/PKCS5Padding");        cipher.init(Cipher.DECRYPT_MODE,sekey,param);        byte[] decrypted = cipher.doFinal(data);        return decrypted;    } catch (Exception e) {        e.printStackTrace();        return null;    }}

 

Rfc2898DeriveBytes解密如何通過java實現