原文来自:http://www.iteye.com/topic/243970
Base64:
package com.cxlh.mm; public class Base64 { final static String baseTable = "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/"; /** * Encode a byte array. * * @param bytes a byte array to be encoded. * @return encoded object as a String object. */ public static String encode(byte[] bytes) { StringBuffer tmp = new StringBuffer(); int i = 0; byte pos; for(i=0; i < (bytes.length - bytes.length%3); i+=3) { pos = (byte) ((bytes[i] >> 2) & 63); tmp.append(baseTable.charAt(pos)); pos = (byte) (((bytes[i] & 3) << 4) + ((bytes[i+1] >> 4) & 15)); tmp.append(baseTable.charAt( pos )); pos = (byte) (((bytes[i+1] & 15) << 2) + ((bytes[i+2] >> 6) & 3)); tmp.append(baseTable.charAt(pos)); pos = (byte) (((bytes[i+2]) & 63)); tmp.append(baseTable.charAt(pos)); // Add a new line for each 76 chars. // 76*3/4 = 57 if(((i+2)%56) == 0) { tmp.append("\r\n"); } } if(bytes.length % 3 != 0) { if(bytes.length % 3 == 2) { pos = (byte) ((bytes[i] >> 2) & 63); tmp.append(baseTable.charAt(pos)); pos = (byte) (((bytes[i] & 3) << 4) + ((bytes[i+1] >> 4) & 15)); tmp.append(baseTable.charAt( pos )); pos = (byte) ((bytes[i+1] & 15) << 2); tmp.append(baseTable.charAt(pos)); tmp.append("="); } else if(bytes.length % 3 == 1) { pos = (byte) ((bytes[i] >> 2) & 63); tmp.append(baseTable.charAt(pos)); pos = (byte) ((bytes[i] & 3) << 4); tmp.append(baseTable.charAt( pos )); tmp.append("=="); } } return tmp.toString(); } /** * Encode a String object. * * @param src a String object to be encoded with Base64 schema. * @return encoded String object. */ public static String encode(String src) { return encode(src.getBytes()); } public static byte[] decode(String src) throws Exception { byte[] bytes = null; StringBuffer buf = new StringBuffer(src); // First, Remove white spaces (\r\n, \t, " "); int i = 0; char c = ' '; char oc = ' '; while( i < buf.length()) { oc = c; c = buf.charAt(i); if( oc == '\r' && c == '\n') { buf.deleteCharAt(i); buf.deleteCharAt(i-1); i -= 2; } else if( c == '\t') { buf.deleteCharAt(i); i --; } else if( c == ' ') { i --; } i++; } // The source should consists groups with length of 4 chars. if(buf.length() % 4 != 0) { throw new Exception("Base64 decoding invalid length"); } // pre-set byte array size. bytes = new byte[3 * (buf.length() / 4)]; //int len = 3 * (buf.length() % 4); //System.out.println("Size of Bytes array: " + len); int index = 0; // Now decode each group for(i = 0; i < buf.length(); i+=4) { byte data = 0; int nGroup = 0; for(int j = 0; j < 4; j++) { char theChar = buf.charAt(i + j); if(theChar == '=') { data = 0; } else { data = getBaseTableIndex(theChar); } if(data == -1) { throw new Exception("Base64 decoding bad character"); } nGroup = 64*nGroup + data; } bytes[index] = (byte) (255 & (nGroup >> 16)); index ++; bytes[index] = (byte) (255 & (nGroup >> 8)); index ++; bytes[index] = (byte) (255 & (nGroup)); index ++; } byte[] newBytes = new byte[index]; for(i = 0; i < index; i++) { newBytes[i] = bytes[i]; } return newBytes; } /** * Find index number in base table for a given character. * */ protected static byte getBaseTableIndex(char c) { byte index = -1; for(byte i = 0; i < baseTable.length(); i ++) { if(baseTable.charAt(i) == c) { index = i; break; } } return index; } public static void main(String[] args) { String encodedString = Base64.encode("Hello PHPRPC".getBytes()); System.out.println(encodedString); } }
MD5:
public class MD5 { /* 下面这些S11-S44实际上是一个4*4的矩阵,在原始的C实现中是用#define 实现的, 这里把它们实现成为static final是表示了只读,切能在同一个进程空间内的多个 Instance间共享*/ static final int S11 = 7; static final int S12 = 12; static final int S13 = 17; static final int S14 = 22; static final int S21 = 5; static final int S22 = 9; static final int S23 = 14; static final int S24 = 20; static final int S31 = 4; static final int S32 = 11; static final int S33 = 16; static final int S34 = 23; static final int S41 = 6; static final int S42 = 10; static final int S43 = 15; static final int S44 = 21; static final byte[] PADDING = { -128, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0 }; /* 下面的三个成员是MD5计算过程中用到的3个核心数据,在原始的C实现中 被定义到MD5_CTX结构中 */ private long[] state = new long[4]; // state (ABCD) private long[] count = new long[2]; // number of bits, modulo 2^64 (lsb first) private byte[] buffer = new byte[64]; // input buffer /* digestHexStr是MD5的唯一一个公共成员,是最新一次计算结果的 16进制ASCII表示. */ public String digestHexStr; /* digest,是最新一次计算结果的2进制内部表示,表示128bit的MD5值. */ private byte[] digest = new byte[16]; /** * 得到MD5加密后的字符串 * @param inbuf * @return */ public String getStrToMD5(String inbuf) { md5Init(); md5Update(inbuf.getBytes(), inbuf.length()); md5Final(); digestHexStr = ""; for (int i = 0; i < 16; i++) { digestHexStr += byteHEX(digest[i]); } return digestHexStr; } /* getMD5ofStr是类MD5最主要的公共方法,入口参数是你想要进行MD5变换的字符串 返回的是变换完的结果,这个结果是从公共成员digestHexStr取得的. */ public String getMD5ofStr(String inbuf) { md5Init(); md5Update(inbuf.getBytes(), inbuf.length()); md5Final(); digestHexStr = ""; for (int i = 0; i < 16; i++) { digestHexStr += byteHEX(digest[i]); } digestHexStr=digestHexStr.substring(8,24); return digestHexStr; } // 这是MD5这个类的标准构造函数,JavaBean要求有一个public的并且没有参数的构造函数 public MD5() { md5Init(); return; } /* md5Init是一个初始化函数,初始化核心变量,装入标准的幻数 */ private void md5Init() { count[0] = 0L; count[1] = 0L; ///* Load magic initialization constants. state[0] = 0x67452301L; state[1] = 0xefcdab89L; state[2] = 0x98badcfeL; state[3] = 0x10325476L; return; } /* F, G, H ,I 是4个基本的MD5函数,在原始的MD5的C实现中,由于它们是 简单的位运算,可能出于效率的考虑把它们实现成了宏,在java中,我们把它们 实现成了private方法,名字保持了原来C中的。 */ private long F(long x, long y, long z) { return (x & y) | ((~x) & z); } private long G(long x, long y, long z) { return (x & z) | (y & (~z)); } private long H(long x, long y, long z) { return x ^ y ^ z; } private long I(long x, long y, long z) { return y ^ (x | (~z)); } /* FF,GG,HH和II将调用F,G,H,I进行近一步变换 FF, GG, HH, and II transformations for rounds 1, 2, 3, and 4. Rotation is separate from addition to prevent recomputation. */ private long FF(long a, long b, long c, long d, long x, long s, long ac) { a += F(b, c, d) + x + ac; a = ((int) a << s) | ((int) a >>> (32 - s)); a += b; return a; } private long GG(long a, long b, long c, long d, long x, long s, long ac) { a += G(b, c, d) + x + ac; a = ((int) a << s) | ((int) a >>> (32 - s)); a += b; return a; } private long HH(long a, long b, long c, long d, long x, long s, long ac) { a += H(b, c, d) + x + ac; a = ((int) a << s) | ((int) a >>> (32 - s)); a += b; return a; } private long II(long a, long b, long c, long d, long x, long s, long ac) { a += I(b, c, d) + x + ac; a = ((int) a << s) | ((int) a >>> (32 - s)); a += b; return a; } /* md5Update是MD5的主计算过程,inbuf是要变换的字节串,inputlen是长度,这个 函数由getMD5ofStr调用,调用之前需要调用md5init,因此把它设计成private的 */ private void md5Update(byte[] inbuf, int inputLen) { int i, index, partLen; byte[] block = new byte[64]; index = (int) (count[0] >>> 3) & 0x3F; // /* Update number of bits */ if ((count[0] += (inputLen << 3)) < (inputLen << 3)) count[1]++; count[1] += (inputLen >>> 29); partLen = 64 - index; // Transform as many times as possible. if (inputLen >= partLen) { md5Memcpy(buffer, inbuf, index, 0, partLen); md5Transform(buffer); for (i = partLen; i + 63 < inputLen; i += 64) { md5Memcpy(block, inbuf, 0, i, 64); md5Transform(block); } index = 0; } else i = 0; ///* Buffer remaining input */ md5Memcpy(buffer, inbuf, index, i, inputLen - i); } /* md5Final整理和填写输出结果 */ private void md5Final() { byte[] bits = new byte[8]; int index, padLen; ///* Save number of bits */ Encode(bits, count, 8); ///* Pad out to 56 mod 64. index = (int) (count[0] >>> 3) & 0x3f; padLen = (index < 56) ? (56 - index) : (120 - index); md5Update(PADDING, padLen); ///* Append length (before padding) */ md5Update(bits, 8); ///* Store state in digest */ Encode(digest, state, 16); } /* md5Memcpy是一个内部使用的byte数组的块拷贝函数,从input的inpos开始把len长度的 字节拷贝到output的outpos位置开始 */ private void md5Memcpy( byte[] output, byte[] input, int outpos, int inpos, int len) { int i; for (i = 0; i < len; i++) output[outpos + i] = input[inpos + i]; } /* md5Transform是MD5核心变换程序,有md5Update调用,block是分块的原始字节 */ private void md5Transform(byte block[]) { long a = state[0], b = state[1], c = state[2], d = state[3]; long[] x = new long[16]; Decode(x, block, 64); /* Round 1 */ a = FF(a, b, c, d, x[0], S11, 0xd76aa478L); /* 1 */ d = FF(d, a, b, c, x[1], S12, 0xe8c7b756L); /* 2 */ c = FF(c, d, a, b, x[2], S13, 0x242070dbL); /* 3 */ b = FF(b, c, d, a, x[3], S14, 0xc1bdceeeL); /* 4 */ a = FF(a, b, c, d, x[4], S11, 0xf57c0fafL); /* 5 */ d = FF(d, a, b, c, x[5], S12, 0x4787c62aL); /* 6 */ c = FF(c, d, a, b, x[6], S13, 0xa8304613L); /* 7 */ b = FF(b, c, d, a, x[7], S14, 0xfd469501L); /* 8 */ a = FF(a, b, c, d, x[8], S11, 0x698098d8L); /* 9 */ d = FF(d, a, b, c, x[9], S12, 0x8b44f7afL); /* 10 */ c = FF(c, d, a, b, x[10], S13, 0xffff5bb1L); /* 11 */ b = FF(b, c, d, a, x[11], S14, 0x895cd7beL); /* 12 */ a = FF(a, b, c, d, x[12], S11, 0x6b901122L); /* 13 */ d = FF(d, a, b, c, x[13], S12, 0xfd987193L); /* 14 */ c = FF(c, d, a, b, x[14], S13, 0xa679438eL); /* 15 */ b = FF(b, c, d, a, x[15], S14, 0x49b40821L); /* 16 */ /* Round 2 */ a = GG(a, b, c, d, x[1], S21, 0xf61e2562L); /* 17 */ d = GG(d, a, b, c, x[6], S22, 0xc040b340L); /* 18 */ c = GG(c, d, a, b, x[11], S23, 0x265e5a51L); /* 19 */ b = GG(b, c, d, a, x[0], S24, 0xe9b6c7aaL); /* 20 */ a = GG(a, b, c, d, x[5], S21, 0xd62f105dL); /* 21 */ d = GG(d, a, b, c, x[10], S22, 0x2441453L); /* 22 */ c = GG(c, d, a, b, x[15], S23, 0xd8a1e681L); /* 23 */ b = GG(b, c, d, a, x[4], S24, 0xe7d3fbc8L); /* 24 */ a = GG(a, b, c, d, x[9], S21, 0x21e1cde6L); /* 25 */ d = GG(d, a, b, c, x[14], S22, 0xc33707d6L); /* 26 */ c = GG(c, d, a, b, x[3], S23, 0xf4d50d87L); /* 27 */ b = GG(b, c, d, a, x[8], S24, 0x455a14edL); /* 28 */ a = GG(a, b, c, d, x[13], S21, 0xa9e3e905L); /* 29 */ d = GG(d, a, b, c, x[2], S22, 0xfcefa3f8L); /* 30 */ c = GG(c, d, a, b, x[7], S23, 0x676f02d9L); /* 31 */ b = GG(b, c, d, a, x[12], S24, 0x8d2a4c8aL); /* 32 */ /* Round 3 */ a = HH(a, b, c, d, x[5], S31, 0xfffa3942L); /* 33 */ d = HH(d, a, b, c, x[8], S32, 0x8771f681L); /* 34 */ c = HH(c, d, a, b, x[11], S33, 0x6d9d6122L); /* 35 */ b = HH(b, c, d, a, x[14], S34, 0xfde5380cL); /* 36 */ a = HH(a, b, c, d, x[1], S31, 0xa4beea44L); /* 37 */ d = HH(d, a, b, c, x[4], S32, 0x4bdecfa9L); /* 38 */ c = HH(c, d, a, b, x[7], S33, 0xf6bb4b60L); /* 39 */ b = HH(b, c, d, a, x[10], S34, 0xbebfbc70L); /* 40 */ a = HH(a, b, c, d, x[13], S31, 0x289b7ec6L); /* 41 */ d = HH(d, a, b, c, x[0], S32, 0xeaa127faL); /* 42 */ c = HH(c, d, a, b, x[3], S33, 0xd4ef3085L); /* 43 */ b = HH(b, c, d, a, x[6], S34, 0x4881d05L); /* 44 */ a = HH(a, b, c, d, x[9], S31, 0xd9d4d039L); /* 45 */ d = HH(d, a, b, c, x[12], S32, 0xe6db99e5L); /* 46 */ c = HH(c, d, a, b, x[15], S33, 0x1fa27cf8L); /* 47 */ b = HH(b, c, d, a, x[2], S34, 0xc4ac5665L); /* 48 */ /* Round 4 */ a = II(a, b, c, d, x[0], S41, 0xf4292244L); /* 49 */ d = II(d, a, b, c, x[7], S42, 0x432aff97L); /* 50 */ c = II(c, d, a, b, x[14], S43, 0xab9423a7L); /* 51 */ b = II(b, c, d, a, x[5], S44, 0xfc93a039L); /* 52 */ a = II(a, b, c, d, x[12], S41, 0x655b59c3L); /* 53 */ d = II(d, a, b, c, x[3], S42, 0x8f0ccc92L); /* 54 */ c = II(c, d, a, b, x[10], S43, 0xffeff47dL); /* 55 */ b = II(b, c, d, a, x[1], S44, 0x85845dd1L); /* 56 */ a = II(a, b, c, d, x[8], S41, 0x6fa87e4fL); /* 57 */ d = II(d, a, b, c, x[15], S42, 0xfe2ce6e0L); /* 58 */ c = II(c, d, a, b, x[6], S43, 0xa3014314L); /* 59 */ b = II(b, c, d, a, x[13], S44, 0x4e0811a1L); /* 60 */ a = II(a, b, c, d, x[4], S41, 0xf7537e82L); /* 61 */ d = II(d, a, b, c, x[11], S42, 0xbd3af235L); /* 62 */ c = II(c, d, a, b, x[2], S43, 0x2ad7d2bbL); /* 63 */ b = II(b, c, d, a, x[9], S44, 0xeb86d391L); /* 64 */ state[0] += a; state[1] += b; state[2] += c; state[3] += d; } /*Encode把long数组按顺序拆成byte数组,因为java的long类型是64bit的, 只拆低32bit,以适应原始C实现的用途 */ private void Encode(byte[] output, long[] input, int len) { int i, j; for (i = 0, j = 0; j < len; i++, j += 4) { output[j] = (byte) (input[i] & 0xffL); output[j + 1] = (byte) ((input[i] >>> 8) & 0xffL); output[j + 2] = (byte) ((input[i] >>> 16) & 0xffL); output[j + 3] = (byte) ((input[i] >>> 24) & 0xffL); } } /*Decode把byte数组按顺序合成成long数组,因为java的long类型是64bit的, 只合成低32bit,高32bit清零,以适应原始C实现的用途 */ private void Decode(long[] output, byte[] input, int len) { int i, j; for (i = 0, j = 0; j < len; i++, j += 4) output[i] = b2iu(input[j]) | (b2iu(input[j + 1]) << 8) | (b2iu(input[j + 2]) << 16) | (b2iu(input[j + 3]) << 24); return; } /* b2iu是我写的一个把byte按照不考虑正负号的原则的"升位"程序,因为java没有unsigned运算 */ public static long b2iu(byte b) { return b < 0 ? b & 0x7F + 128 : b; } /*byteHEX(),用来把一个byte类型的数转换成十六进制的ASCII表示, 因为java中的byte的toString无法实现这一点,我们又没有C语言中的 sprintf(outbuf,"%02X",ib) */ public static String byteHEX(byte ib) { char[] Digit = { '0', '1', '2', '3', '4', '5', '6', '7', '8', '9', 'a', 'b', 'c', 'd', 'e', 'f' }; char[] ob = new char[2]; ob[0] = Digit[(ib >>> 4) & 0X0F]; ob[1] = Digit[ib & 0X0F]; String s = new String(ob); return s; } public static void main(String args[]) { MD5 m = new MD5(); String abc = m.getMD5ofStr("123456"); System.out.println(abc); }
复杂加密:
public static String Encrypt(String str) { Security.addProvider(new com.sun.crypto.provider.SunJCE()); sun.misc.BASE64Encoder encoder = new sun.misc.BASE64Encoder(); String strOut = ""; try { // DES算法要求有一个可信任的随机数源 SecureRandom sr = new SecureRandom(); // 从原始密匙数据创建DESKeySpec对象 DESKeySpec dks = new DESKeySpec(KEY_STRING.getBytes()); // 创建一个密匙工厂,然后用它把DESKeySpec转换成 // 一个SecretKey对象 SecretKeyFactory keyFactory = SecretKeyFactory.getInstance("DES"); SecretKey key = keyFactory.generateSecret(dks); // Cipher对象实际完成加密操作 Cipher cipher = Cipher.getInstance("DES"); // 用密匙初始化Cipher对象 cipher.init(Cipher.ENCRYPT_MODE, key, sr); // 现在,获取数据并加密 byte data[] = str.getBytes(); /* 用某种方法获取数据 */ // 正式执行加密操作 byte encryptedData[] = cipher.doFinal(data); strOut = encoder.encode(encryptedData); } catch (Exception e) { e.printStackTrace(); } return strOut; } public static String Decrypt(String s) { Security.addProvider(new com.sun.crypto.provider.SunJCE()); String strOut = ""; sun.misc.BASE64Decoder decoder = new sun.misc.BASE64Decoder(); try { // DES算法要求有一个可信任的随机数源 SecureRandom sr = new SecureRandom(); // 从原始密匙数据创建一个DESKeySpec对象 DESKeySpec dks = new DESKeySpec(KEY_STRING.getBytes()); // 创建一个密匙工厂,然后用它把DESKeySpec对象转换成 // 一个SecretKey对象 SecretKeyFactory keyFactory = SecretKeyFactory.getInstance("DES"); SecretKey key = keyFactory.generateSecret(dks); // Cipher对象实际完成解密操作 Cipher cipher = Cipher.getInstance("DES"); // 用密匙初始化Cipher对象 cipher.init(Cipher.DECRYPT_MODE, key, sr); // 现在,获取数据并解密 byte encryptedData[] = decoder.decodeBuffer(s); /* 获得经过加密的数据 */ // 正式执行解密操作 byte decryptedData[] = cipher.doFinal(encryptedData); strOut = new String(decryptedData); } catch (Exception e) { e.printStackTrace(); } return strOut; } public static void main(String[] args){ String a=Encrypt("aaa"); System.out.print(a); String b=Decrypt("5991bf21cbe98232".toUpperCase()); System.out.print(b);