如何用Java中的密码加密和解密String（Pc不是移动平台）？

我想加密一个字符串然后把它放在一个文件上。 也想在我想要的时候解密它。 我不需要非常强大的安全性。 我只是想让其他人更难获取我的数据。

我尝试了几种方法。 这是这些。

Md5加密：

如何在Android中散列字符串？

public static final String md5(final String toEncrypt) { try { final MessageDigest digest = MessageDigest.getInstance("md5"); digest.update(toEncrypt.getBytes()); final byte[] bytes = digest.digest(); final StringBuilder sb = new StringBuilder(); for (int i = 0; i < bytes.length; i++) { sb.append(String.format("%02X", bytes[i])); } return sb.toString().toLowerCase(); } catch (Exception exc) { return ""; // Impossibru! } } 

我尝试了这个function，并能够加密一个字符串，但我不能解密它的数据。 所以这不是解决方案。

DES加密：

在java中加密和解密String

密码短语是自动生成的。 密码始终是一样的吗？ 然后我的安全在哪里。 所以这也不是我的解决方案。

AES加密：

如何使用另一个字符串作为密码加密/解密字符串？

我也从这个链接尝试了Aes。 这里的密钥也是自动生成的？

还有别的办法吗？

Answer 1

 package com.example; import java.security.Key; import javax.crypto.Cipher; import javax.crypto.spec.SecretKeySpec; public class StrongAES { public void run() { try { String text = "Hello World"; String key = "Bar12345Bar12345"; // 128 bit key // Create key and cipher Key aesKey = new SecretKeySpec(key.getBytes(), "AES"); Cipher cipher = Cipher.getInstance("AES"); // encrypt the text cipher.init(Cipher.ENCRYPT_MODE, aesKey); byte[] encrypted = cipher.doFinal(text.getBytes()); System.err.println(new String(encrypted)); // decrypt the text cipher.init(Cipher.DECRYPT_MODE, aesKey); String decrypted = new String(cipher.doFinal(encrypted)); System.err.println(decrypted); } catch(Exception e) { e.printStackTrace(); } } public static void main(String[] args) { StrongAES app = new StrongAES(); app.run(); } } 

Answer 2

 package com.ezeon.util.gen; import java.io.IOException; import java.io.UnsupportedEncodingException; import java.security.InvalidAlgorithmParameterException; import java.security.InvalidKeyException; import java.security.NoSuchAlgorithmException; import java.security.spec.AlgorithmParameterSpec; import java.security.spec.InvalidKeySpecException; import java.security.spec.KeySpec; import javax.crypto.*; import javax.crypto.spec.PBEKeySpec; import javax.crypto.spec.PBEParameterSpec; /*** Encryption and Decryption of String data; PBE(Password Based Encryption and Decryption) * @author Vikram */ public class CryptoUtil { Cipher ecipher; Cipher dcipher; // 8-byte Salt byte[] salt = { (byte) 0xA9, (byte) 0x9B, (byte) 0xC8, (byte) 0x32, (byte) 0x56, (byte) 0x35, (byte) 0xE3, (byte) 0x03 }; // Iteration count int iterationCount = 19; public CryptoUtil() { } /** * * @param secretKey Key used to encrypt data * @param plainText Text input to be encrypted * @return Returns encrypted text * @throws java.security.NoSuchAlgorithmException * @throws java.security.spec.InvalidKeySpecException * @throws javax.crypto.NoSuchPaddingException * @throws java.security.InvalidKeyException * @throws java.security.InvalidAlgorithmParameterException * @throws java.io.UnsupportedEncodingException * @throws javax.crypto.IllegalBlockSizeException * @throws javax.crypto.BadPaddingException * */ public String encrypt(String secretKey, String plainText) throws NoSuchAlgorithmException, InvalidKeySpecException, NoSuchPaddingException, InvalidKeyException, InvalidAlgorithmParameterException, UnsupportedEncodingException, IllegalBlockSizeException, BadPaddingException { //Key generation for enc and desc KeySpec keySpec = new PBEKeySpec(secretKey.toCharArray(), salt, iterationCount); SecretKey key = SecretKeyFactory.getInstance("PBEWithMD5AndDES").generateSecret(keySpec); // Prepare the parameter to the ciphers AlgorithmParameterSpec paramSpec = new PBEParameterSpec(salt, iterationCount); //Enc process ecipher = Cipher.getInstance(key.getAlgorithm()); ecipher.init(Cipher.ENCRYPT_MODE, key, paramSpec); String charSet = "UTF-8"; byte[] in = plainText.getBytes(charSet); byte[] out = ecipher.doFinal(in); String encStr = new String(Base64.getEncoder().encode(out)); return encStr; } /** * @param secretKey Key used to decrypt data * @param encryptedText encrypted text input to decrypt * @return Returns plain text after decryption * @throws java.security.NoSuchAlgorithmException * @throws java.security.spec.InvalidKeySpecException * @throws javax.crypto.NoSuchPaddingException * @throws java.security.InvalidKeyException * @throws java.security.InvalidAlgorithmParameterException * @throws java.io.UnsupportedEncodingException * @throws javax.crypto.IllegalBlockSizeException * @throws javax.crypto.BadPaddingException */ public String decrypt(String secretKey, String encryptedText) throws NoSuchAlgorithmException, InvalidKeySpecException, NoSuchPaddingException, InvalidKeyException, InvalidAlgorithmParameterException, UnsupportedEncodingException, IllegalBlockSizeException, BadPaddingException, IOException { //Key generation for enc and desc KeySpec keySpec = new PBEKeySpec(secretKey.toCharArray(), salt, iterationCount); SecretKey key = SecretKeyFactory.getInstance("PBEWithMD5AndDES").generateSecret(keySpec); // Prepare the parameter to the ciphers AlgorithmParameterSpec paramSpec = new PBEParameterSpec(salt, iterationCount); //Decryption process; same key will be used for decr dcipher = Cipher.getInstance(key.getAlgorithm()); dcipher.init(Cipher.DECRYPT_MODE, key, paramSpec); byte[] enc = Base64.getDecoder().decode(encryptedText); byte[] utf8 = dcipher.doFinal(enc); String charSet = "UTF-8"; String plainStr = new String(utf8, charSet); return plainStr; } public static void main(String[] args) throws Exception { CryptoUtil cryptoUtil=new CryptoUtil(); String key="ezeon8547"; String plain="This is an important message"; String enc=cryptoUtil.encrypt(key, plain); System.out.println("Original text: "+plain); System.out.println("Encrypted text: "+enc); String plainAfter=cryptoUtil.decrypt(key, enc); System.out.println("Original text after decryption: "+plainAfter); } } 

Answer 3

很好的回答Vignesh，谢谢！

我只想补充一点，如果你想以某种方式将加密的字节数组存储为String然后检索并解密它（通常用于混淆数据库值），你可以使用这种方法：

 import java.security.Key; import javax.crypto.Cipher; import javax.crypto.spec.SecretKeySpec; public class StrongAES { public void run() { try { String text = "Hello World"; String key = "Bar12345Bar12345"; // 128 bit key // Create key and cipher Key aesKey = new SecretKeySpec(key.getBytes(), "AES"); Cipher cipher = Cipher.getInstance("AES"); // encrypt the text cipher.init(Cipher.ENCRYPT_MODE, aesKey); byte[] encrypted = cipher.doFinal(text.getBytes()); StringBuilder sb = new StringBuilder(); for (byte b: encrypted) { sb.append((char)b); } // the encrypted String String enc = sb.toString(); System.out.println("encrypted:" + enc); // now convert the string to byte array // for decryption byte[] bb = new byte[enc.length()]; for (int i=0; i 

Answer 4

加密：

  public static String encrypt(String strClearText,String strKey) throws Exception{ String strData=""; try { SecretKeySpec skeyspec=new SecretKeySpec(strKey.getBytes(),"Blowfish"); Cipher cipher=Cipher.getInstance("Blowfish"); cipher.init(Cipher.ENCRYPT_MODE, skeyspec); byte[] encrypted=cipher.doFinal(strClearText.getBytes()); strData=new String(encrypted); } catch (Exception e) { e.printStackTrace(); throw new Exception(e); } return strData; } 

解密：

 public static String decrypt(String strEncrypted,String strKey) throws Exception{ String strData=""; try { SecretKeySpec skeyspec=new SecretKeySpec(strKey.getBytes(),"Blowfish"); Cipher cipher=Cipher.getInstance("Blowfish"); cipher.init(Cipher.DECRYPT_MODE, skeyspec); byte[] decrypted=cipher.doFinal(strEncrypted.getBytes()); strData=new String(decrypted); } catch (Exception e) { e.printStackTrace(); throw new Exception(e); } return strData; } 

Source 如何在Java中轻松加密和解密文本

Answer 5

使用这将是有效的肯定

 import java.io.IOException; import java.io.UnsupportedEncodingException; import java.security.GeneralSecurityException; import javax.crypto.Cipher; import javax.crypto.SecretKey; import javax.crypto.SecretKeyFactory; import javax.crypto.spec.PBEKeySpec; import javax.crypto.spec.PBEParameterSpec; import sun.misc.BASE64Decoder; import sun.misc.BASE64Encoder; public class ProtectedConfigFile { private static final char[] PASSWORD = "enfldsgbnlsngdlksdsgm".toCharArray(); private static final byte[] SALT = { (byte) 0xde, (byte) 0x33, (byte) 0x10, (byte) 0x12, (byte) 0xde, (byte) 0x33, (byte) 0x10, (byte) 0x12, }; public static void main(String[] args) throws Exception { String originalPassword = "Aman"; System.out.println("Original password: " + originalPassword); String encryptedPassword = encrypt(originalPassword); System.out.println("Encrypted password: " + encryptedPassword); String decryptedPassword = decrypt(encryptedPassword); System.out.println("Decrypted password: " + decryptedPassword); } private static String encrypt(String property) throws GeneralSecurityException, UnsupportedEncodingException { SecretKeyFactory keyFactory = SecretKeyFactory.getInstance("PBEWithMD5AndDES"); SecretKey key = keyFactory.generateSecret(new PBEKeySpec(PASSWORD)); Cipher pbeCipher = Cipher.getInstance("PBEWithMD5AndDES"); pbeCipher.init(Cipher.ENCRYPT_MODE, key, new PBEParameterSpec(SALT, 20)); return base64Encode(pbeCipher.doFinal(property.getBytes("UTF-8"))); } private static String base64Encode(byte[] bytes) { // NB: This class is internal, and you probably should use another impl return new BASE64Encoder().encode(bytes); } private static String decrypt(String property) throws GeneralSecurityException, IOException { SecretKeyFactory keyFactory = SecretKeyFactory.getInstance("PBEWithMD5AndDES"); SecretKey key = keyFactory.generateSecret(new PBEKeySpec(PASSWORD)); Cipher pbeCipher = Cipher.getInstance("PBEWithMD5AndDES"); pbeCipher.init(Cipher.DECRYPT_MODE, key, new PBEParameterSpec(SALT, 20)); return new String(pbeCipher.doFinal(base64Decode(property)), "UTF-8"); } private static byte[] base64Decode(String property) throws IOException { // NB: This class is internal, and you probably should use another impl return new BASE64Decoder().decodeBuffer(property); } } 

Answer 6

标记为解决方案的代码对我不起作用。 这是我的解决方案。

 /* * http://www.java2s.com/Code/Java/Security/EncryptingaStringwithDES.htm * https://stackoverflow.com/questions/23561104/how-to-encrypt-and-decrypt-string-with-my-passphrase-in-java-pc-not-mobile-plat */ package encryptiondemo; import javax.crypto.Cipher; import javax.crypto.KeyGenerator; import javax.crypto.SecretKey; import javax.crypto.spec.SecretKeySpec; /** * * @author zchumager */ public class EncryptionDemo { Cipher ecipher; Cipher dcipher; EncryptionDemo(SecretKey key) throws Exception { ecipher = Cipher.getInstance("AES"); dcipher = Cipher.getInstance("AES"); ecipher.init(Cipher.ENCRYPT_MODE, key); dcipher.init(Cipher.DECRYPT_MODE, key); } public String encrypt(String str) throws Exception { // Encode the string into bytes using utf-8 byte[] utf8 = str.getBytes("UTF8"); // Encrypt byte[] enc = ecipher.doFinal(utf8); // Encode bytes to base64 to get a string return new sun.misc.BASE64Encoder().encode(enc); } public String decrypt(String str) throws Exception { // Decode base64 to get bytes byte[] dec = new sun.misc.BASE64Decoder().decodeBuffer(str); byte[] utf8 = dcipher.doFinal(dec); // Decode using utf-8 return new String(utf8, "UTF8"); } public static void main(String args []) throws Exception { String data = "Don't tell anybody!"; String k = "Bar12345Bar12345"; //SecretKey key = KeyGenerator.getInstance("AES").generateKey(); SecretKey key = new SecretKeySpec(k.getBytes(), "AES"); EncryptionDemo encrypter = new EncryptionDemo(key); System.out.println("Original String: " + data); String encrypted = encrypter.encrypt(data); System.out.println("Encrypted String: " + encrypted); String decrypted = encrypter.decrypt(encrypted); System.out.println("Decrypted String: " + decrypted); } }