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android平台上AES,DES加解密及问题

在使用java进行AES加密的时候,会用到如下方法:
SecureRandom sr = SecureRandom.getInstance("SHA1PRNG");

但是在android4.2以上进行加密、解密时,会报类似badPadding的异常,但是把该代码替换成一下方法则一切都OK。
SecureRandom sr = SecureRandom.getInstance("SHA1PRNG", "Crypto"); 

AES加密算法:
import java.security.SecureRandom;

import javax.crypto.Cipher;
import javax.crypto.KeyGenerator;
import javax.crypto.SecretKey;
import javax.crypto.spec.SecretKeySpec;

public class AESUtil {

	public static String encrypt(String seed, String cleartext)
			throws Exception {
		byte[] rawKey = getRawKey(seed.getBytes());
		byte[] result = encrypt(rawKey, cleartext.getBytes());
		return toHex(result);
	}

	public static String decrypt(String seed, String encrypted)
			throws Exception {
		byte[] rawKey = getRawKey(seed.getBytes());
		byte[] enc = toByte(encrypted);
		byte[] result = decrypt(rawKey, enc);
		return new String(result);
	}

	private static byte[] getRawKey(byte[] seed) throws Exception {
		KeyGenerator kgen = KeyGenerator.getInstance("AES");
//		SecureRandom sr = SecureRandom.getInstance("SHA1PRNG");
		SecureRandom sr = SecureRandom.getInstance("SHA1PRNG", "Crypto"); 
		sr.setSeed(seed);
		kgen.init(128, sr); // 192 and 256 bits may not be available
		SecretKey skey = kgen.generateKey();
		byte[] raw = skey.getEncoded();
		return raw;
	}

	private static byte[] encrypt(byte[] raw, byte[] clear) throws Exception {
		SecretKeySpec skeySpec = new SecretKeySpec(raw, "AES");
		Cipher cipher = Cipher.getInstance("AES");
		cipher.init(Cipher.ENCRYPT_MODE, skeySpec);
		byte[] encrypted = cipher.doFinal(clear);
		return encrypted;
	}

	private static byte[] decrypt(byte[] raw, byte[] encrypted)
			throws Exception {
		SecretKeySpec skeySpec = new SecretKeySpec(raw, "AES");
		Cipher cipher = Cipher.getInstance("AES");
		cipher.init(Cipher.DECRYPT_MODE, skeySpec);
		byte[] decrypted = cipher.doFinal(encrypted);
		return decrypted;
	}

	public static String toHex(String txt) {
		return toHex(txt.getBytes());
	}

	public static String fromHex(String hex) {
		return new String(toByte(hex));
	}

	public static byte[] toByte(String hexString) {
		int len = hexString.length()/2;
		byte[] result = new byte[len];
		for (int i = 0; i < len; i++)
			result[i] = Integer.valueOf(hexString.substring(2*i, 2*i+2), 16).byteValue();
		return result;
	}

	public static String toHex(byte[] buf) {
		if (buf == null)
			return "";
		StringBuffer result = new StringBuffer(2*buf.length);
		for (int i = 0; i < buf.length; i++) {
			appendHex(result, buf[i]);
		}
		return result.toString();
	}

	private final static String HEX = "0123456789ABCDEF";

	private static void appendHex(StringBuffer sb, byte b) {
		 sb.append(HEX.charAt((b>>4)&0x0f)).append(HEX.charAt(b&0x0f));
	}
}

DES加密算法
import java.io.UnsupportedEncodingException;
import java.security.Key;
import java.util.Locale;

import javax.crypto.Cipher;
import javax.crypto.SecretKeyFactory;
import javax.crypto.spec.DESedeKeySpec;
import javax.crypto.spec.IvParameterSpec;

/**
 * DES加密
 * 
 * @author houjinyun
 * 
 */
public class DesUtils {

	private static final String KEY = "********************";
	
	/**
	 * 对字符串进行DES3加密
	 * 
	 * @param str
	 * @return 加密后的字符串,若失败则返回null
	 */
	public static String encode(String str) {
		try {
			byte[] key = KEY.getBytes("UTF-8");
			byte[] data = http://www.mamicode.com/str.getBytes("UTF-8");>


android平台上AES,DES加解密及问题