Android--DES加密

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Base64.java

import java.io.ByteArrayOutputStream;import java.io.IOException;import java.io.OutputStream;public class Base64 {    private static final char[] legalChars = "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/"            .toCharArray();    /**     * data[]進行編碼     *      * @param data     * @return     */    public static String encode(byte[] data) {                int start = 0;                int len = data.length;                StringBuffer buf = new StringBuffer(data.length * 3 / 2);                 int end = len - 3;                int i = start;                int n = 0;                 while (i <= end) {                    int d = ((((int) data[i]) & 0x0ff) << 16)                            | ((((int) data[i + 1]) & 0x0ff) << 8)                            | (((int) data[i + 2]) & 0x0ff);                     buf.append(legalChars[(d >> 18) & 63]);                    buf.append(legalChars[(d >> 12) & 63]);                    buf.append(legalChars[(d >> 6) & 63]);                    buf.append(legalChars[d & 63]);                     i += 3;                     if (n++ >= 14) {                        n = 0;                        buf.append(" ");                    }                }                 if (i == start + len - 2) {                    int d = ((((int) data[i]) & 0x0ff) << 16)                            | ((((int) data[i + 1]) & 255) << 8);                     buf.append(legalChars[(d >> 18) & 63]);                    buf.append(legalChars[(d >> 12) & 63]);                    buf.append(legalChars[(d >> 6) & 63]);                    buf.append("=");                } else if (i == start + len - 1) {                    int d = (((int) data[i]) & 0x0ff) << 16;                     buf.append(legalChars[(d >> 18) & 63]);                    buf.append(legalChars[(d >> 12) & 63]);                    buf.append("==");                }                 return buf.toString();            }    private static int decode(char c) {        if (c >= ‘A‘ && c <= ‘Z‘)            return ((int) c) - 65;        else if (c >= ‘a‘ && c <= ‘z‘)            return ((int) c) - 97 + 26;        else if (c >= ‘0‘ && c <= ‘9‘)            return ((int) c) - 48 + 26 + 26;        else            switch (c) {            case ‘+‘:                return 62;            case ‘/‘:                return 63;            case ‘=‘:                return 0;            default:                throw new RuntimeException("unexpected code: " + c);            }    }    /**     * Decodes the given Base64 encoded String to a new byte array. The byte     * array holding the decoded data is returned.     */    public static byte[] decode(String s) {        ByteArrayOutputStream bos = new ByteArrayOutputStream();        try {            decode(s, bos);        } catch (IOException e) {            throw new RuntimeException();        }        byte[] decodedBytes = bos.toByteArray();        try {            bos.close();            bos = null;        } catch (IOException ex) {            System.err.println("Error while decoding BASE64: " + ex.toString());        }        return decodedBytes;    }    private static void decode(String s, OutputStream os) throws IOException {        int i = 0;        int len = s.length();        while (true) {            while (i < len && s.charAt(i) <= ‘ ‘)                i++;            if (i == len)                break;            int tri = (decode(s.charAt(i)) << 18)                    + (decode(s.charAt(i + 1)) << 12)                    + (decode(s.charAt(i + 2)) << 6)                    + (decode(s.charAt(i + 3)));            os.write((tri >> 16) & 255);            if (s.charAt(i + 2) == ‘=‘)                break;            os.write((tri >> 8) & 255);            if (s.charAt(i + 3) == ‘=‘)                break;            os.write(tri & 255);            i += 4;        }    }}

DES.java

package cn.crane.game.puzzle.utils.security;import javax.crypto.Cipher;import javax.crypto.spec.IvParameterSpec;import javax.crypto.spec.SecretKeySpec;public class DES {    private static byte[] iv = { 1, 2, 3, 4, 5, 6, 7, 8 };    /**     * 加密     *      * @param encryptString     * @param encryptKey     * @return     * @throws Exception     */    public static String encryptDES(String encryptString, String encryptKey) {        // IvParameterSpec zeroIv = new IvParameterSpec(new byte[8]);        try {            IvParameterSpec zeroIv = new IvParameterSpec(iv);            SecretKeySpec key = new SecretKeySpec(encryptKey.getBytes(), "DES");            Cipher cipher = Cipher.getInstance("DES/CBC/PKCS5Padding");            cipher.init(Cipher.ENCRYPT_MODE, key, zeroIv);            byte[] encryptedData = cipher.doFinal(encryptString.getBytes());            return Base64.encode(encryptedData);        } catch (Exception e) {            e.printStackTrace();        }        return "";    }    /**     * 解密     *      * @param decryptString     * @param decryptKey     * @return     * @throws Exception     */    public static String decryptDES(String decryptString, String decryptKey) {        try {            byte[] byteMi = Base64.decode(decryptString);            IvParameterSpec zeroIv = new IvParameterSpec(iv);            // IvParameterSpec zeroIv = new IvParameterSpec(new byte[8]);            SecretKeySpec key = new SecretKeySpec(decryptKey.getBytes(), "DES");            Cipher cipher = Cipher.getInstance("DES/CBC/PKCS5Padding");            cipher.init(Cipher.DECRYPT_MODE, key, zeroIv);            byte decryptedData[] = cipher.doFinal(byteMi);            return new String(decryptedData);        } catch (Exception e) {            e.printStackTrace();        }        return "";    }}