常用加密解密算法

AES加密算法

package com.xxx.util;

import java.security.SecureRandom;

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

/** * @author YLBF * * @category 类说明 AES算法 */
public class AESCoder {
    private static String encoding = "UTF-8";

    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", "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, new IvParameterSpec(
                new byte[cipher.getBlockSize()]));
        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, new IvParameterSpec(
                new byte[cipher.getBlockSize()]));
        byte[] decrypted = cipher.doFinal(encrypted);
        return decrypted;
    }

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

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

    private 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;
    }

    private 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算法

package com.xxx.util;

import java.security.*;

import javax.crypto.Cipher;
import javax.crypto.SecretKeyFactory;
import javax.crypto.spec.DESKeySpec;

import android.util.Base64;

/** * @author YLBF * * @category 类说明 Des 64位算法 */
public class DESCoder {
    private static String encoding = "UTF-8";
    // 密钥
    private String sKey = "";

    public DESCoder(String sKey) {
        this.sKey = sKey;
    }

    /** * 加密字符串 */
    public String ebotongEncrypto(String str) {
        String result = str;
        if (str != null && str.length() > 0) {
            try {
                byte[] encodeByte = symmetricEncrypto(str.getBytes(encoding));
                result = Base64.encodeToString(encodeByte, Base64.CRLF);

            } catch (Exception e) {
                e.printStackTrace();
            }
        }
        return result;
    }

    /** * 解密字符串 */
    public String ebotongDecrypto(String str) {
        String result = str;
        if (str != null && str.length() > 0) {
            try {
                byte[] encodeByte = Base64.decode(str, Base64.CRLF);

                byte[] decoder = symmetricDecrypto(encodeByte);
                result = new String(decoder, encoding);
            } catch (Exception e) {
                e.printStackTrace();
            }
        }
        return result;
    }

    /** * 加密byte[] */
    public byte[] ebotongEncrypto(byte[] str) {
        byte[] result = null;
        if (str != null && str.length > 0) {
            try {
                byte[] encodeByte = symmetricEncrypto(str);
                result = Base64.encode(encodeByte, Base64.CRLF);

            } catch (Exception e) {
                e.printStackTrace();
            }
        }
        return result;
    }

    /** * 解密byte[] */
    public byte[] ebotongDecrypto(byte[] str) {
        byte[] result = null;
        if (str != null && str.length > 0) {
            try {

                byte[] encodeByte = Base64.decode(new String(str, encoding), Base64.CRLF);
                // byte[] encodeByte = base64decoder.decodeBuffer(new
                // String(str));
                byte[] decoder = symmetricDecrypto(encodeByte);
                result = new String(decoder).getBytes(encoding);
                result = new String(decoder).getBytes();
            } catch (Exception e) {
                e.printStackTrace();
            }
        }
        return result;
    }

    /** * 对称加密字节数组并返回 * * @param byteSource * 需要加密的数据 * @return 经过加密的数据 * @throws Exception */
    public byte[] symmetricEncrypto(byte[] byteSource) throws Exception {
        try {
            int mode = Cipher.ENCRYPT_MODE;
            SecretKeyFactory keyFactory = SecretKeyFactory.getInstance("DES");
            byte[] keyData = sKey.getBytes();
            DESKeySpec keySpec = new DESKeySpec(keyData);
            Key key = keyFactory.generateSecret(keySpec);
            Cipher cipher = Cipher.getInstance("DES");
            cipher.init(mode, key);

            byte[] result = cipher.doFinal(byteSource);
            return result;
        } catch (Exception e) {
            throw e;
        } finally {
        }
    }

    /** * 对称解密字节数组并返回 * * @param byteSource * 需要解密的数据 * @return 经过解密的数据 * @throws Exception */
    public byte[] symmetricDecrypto(byte[] byteSource) throws Exception {
        try {
            int mode = Cipher.DECRYPT_MODE;
            SecretKeyFactory keyFactory = SecretKeyFactory.getInstance("DES");
            byte[] keyData = sKey.getBytes();
            DESKeySpec keySpec = new DESKeySpec(keyData);
            Key key = keyFactory.generateSecret(keySpec);
            Cipher cipher = Cipher.getInstance("DES");
            cipher.init(mode, key);
            byte[] result = cipher.doFinal(byteSource);
            return result;
        } catch (Exception e) {
            throw e;
        } finally {

        }
    }

    /** * 散列算法 * * @param byteSource * 需要散列计算的数据 * @return 经过散列计算的数据 * @throws Exception */
    public static byte[] hashMethod(byte[] byteSource) throws Exception {
        try {
            MessageDigest currentAlgorithm = MessageDigest.getInstance("SHA-1");
            currentAlgorithm.reset();
            currentAlgorithm.update(byteSource);
            return currentAlgorithm.digest();
        } catch (Exception e) {
            throw e;
        }
    }
}