MD5,全称为 Message Digest Algorithm 5(消息摘要算法第五版).详情请参考 维基百科:MD5

MD5加密后是一个字节数组, 但我们一般是取其十六进制的字符串表示法,当然,十六进制数字符串是区分大小写,在 mysql数据库,Java,和JavaScript语言中,一般是使用小写的字符串来表示, 而在 Oracle数据库官方提供的包中,返回的是大写字符串,这算是一个坑,如果你想要执行多次 md5,可能需要转换为小写.

相关的代码如下:

1. Java版MD5

MD5Util.java

package com.cncounter.util.common;import java.security.MessageDigest;import java.security.NoSuchAlgorithmException;/** * Java消息摘要算法 MD5 工具类,其实其他摘要算法的实现也类似 */public class MD5Util { /** * 对文本执行 md5 摘要加密, 此算法与 mysql,JavaScript生成的md5摘要进行过一致性对比. * @param plainText * @return 返回值中的字母为小写 */ public static String md5(String plainText) { if (null == plainText) { plainText = ""; } String MD5Str = ""; try { // JDK 6 支持以下6种消息摘要算法，不区分大小写 // md5,sha(sha-1),md2,sha-256,sha-384,sha-512 MessageDigest md = MessageDigest.getInstance("MD5"); md.update(plainText.getBytes()); byte b[] = md.digest(); int i; StringBuilder builder = new StringBuilder(32); for (int offset = 0; offset < b.length; offset++) { i = b[offset]; if (i < 0) i += 256; if (i < 16) builder.append("0"); builder.append(Integer.toHexString(i)); } MD5Str = builder.toString(); // LogUtil.println("result: " + buf.toString());// 32位的加密 } catch (NoSuchAlgorithmException e) { e.printStackTrace(); } return MD5Str; } // 一个简版测试 public static void main(String[] args) { String m1 = md5("1"); String m2 = md5(m1); /* 输出为 * m1=c4ca4238a0b923820dcc509a6f75849b * m2=28c8edde3d61a0411511d3b1866f0636 */ System.out.println("m1="+m1); System.out.println("m2="+m2); }}

2. MySQL版MD5

MySQL直接支持 md5函数调用

select md5('1') as m1, md5(md5('1')) as m2;

执行结果为:

MariaDB [(none)]> select md5('1') as m1, md5(md5('1')) as m2;+----------------------------------+----------------------------------+| m1 | m2 |+----------------------------------+----------------------------------+| c4ca4238a0b923820dcc509a6f75849b | 28c8edde3d61a0411511d3b1866f0636 |+----------------------------------+----------------------------------+1 row in set (0.00 sec)

3. JavaScript 版MD5函数

md5.js 代码如下:

// 括号表达式, (xxxxx) 是用来将内部的语句、表达式的结果作为一个结果.// 常见的是将json字符串用 eval 解析时,需要 eval("(" +jsonstr+ ")");// () 内部定义了一个空间, 里面定义的变量不会污染到全局空间,很适合做lib// (function UMD(对象/函数名name, 上下文this, 函数/对象的定义)) 返回一个匿名函数// 因为第一个括号内 的结果是一个函数,而函数可以这样调用: (function(形参){})(实参);// 这种匿名函数被浏览器解析后会自动执行一次.(function UMD(name, context, definition) { if ( typeof module !== "undefined" && module.exports) { // 如果 module 存在,并且module.exports存在,则将赋值结果赋给 它 // 可以不用管 module.exports = definition(); } else if ( typeof define === "function" && define.amd) { // 如果 define 这个函数存在,应该是另一个基础类库，则使用define // 可以不用管 define(definition); } else { // 简单一点,可以看成: 调用传入的definition函数，将返回的对象绑定到全局空间 // 当然,根据传入的上下文不同,也可以绑定到其他对象下面,成为一个属性方法. context[name] = definition(name, context); }})("md5", this, function DEF(name, context) {"use strict"; // 上面的 use strict 表示严格语法模式,有错误就拒绝执行. // 而普通的JS,是解释执行,不执行的地方,有些错误也不影响其他代码的执行 // 作为类库,使用严格模式是很有必要的.严格模式声明必须放到一个namespace空间的最起始处. // var old_public_api = (context || {})[name]; // 最后要返回的对象/函数. function md5_func(text) { return hex_md5(text); }; // 下面一堆是具体的算法... 可以先不用管 ///////////////////////////////////////////////////// //计算MD5 var hexcase = 0; function hex_md5(a) { if (a == "") return a; return rstr2hex(rstr_md5(str2rstr_utf8(a))) }; function hex_hmac_md5(a, b) { return rstr2hex(rstr_hmac_md5(str2rstr_utf8(a), str2rstr_utf8(b))) }; function md5_vm_test() { return hex_md5("abc").toLowerCase() == "900150983cd24fb0d6963f7d28e17f72" }; function rstr_md5(a) { return binl2rstr(binl_md5(rstr2binl(a), a.length * 8)) }; function rstr_hmac_md5(c, f) { var e = rstr2binl(c); if (e.length > 16) { e = binl_md5(e, c.length * 8) } var a = Array(16), d = Array(16); for (var b = 0; b < 16; b++) { a[b] = e[b] ^ 909522486; d[b] = e[b] ^ 1549556828 } var g = binl_md5(a.concat(rstr2binl(f)), 512 + f.length * 8); return binl2rstr(binl_md5(d.concat(g), 512 + 128)) }; function rstr2hex(c) { try { hexcase } catch(g) { hexcase = 0 } var f = hexcase ? "0123456789ABCDEF" : "0123456789abcdef"; var b = ""; var a; for (var d = 0; d < c.length; d++) { a = c.charCodeAt(d); b += f.charAt((a >>> 4) & 15) + f.charAt(a & 15) } return b }; function str2rstr_utf8(c) { var b = ""; var d = -1; var a, e; while (++d < c.length) { a = c.charCodeAt(d); e = d + 1 < c.length ? c.charCodeAt(d + 1) : 0; if (55296 <= a && a <= 56319 && 56320 <= e && e <= 57343) { a = 65536 + ((a & 1023) << 10) + (e & 1023); d++ } if (a <= 127) { b += String.fromCharCode(a) } else { if (a <= 2047) { b += String.fromCharCode(192 | ((a >>> 6) & 31), 128 | (a & 63)) } else { if (a <= 65535) { b += String.fromCharCode(224 | ((a >>> 12) & 15), 128 | ((a >>> 6) & 63), 128 | (a & 63)) } else { if (a <= 2097151) { b += String.fromCharCode(240 | ((a >>> 18) & 7), 128 | ((a >>> 12) & 63), 128 | ((a >>> 6) & 63), 128 | (a & 63)) } } } } } return b }; function rstr2binl(b) { var a = Array(b.length >> 2); for (var c = 0; c < a.length; c++) { a[c] = 0 } for (var c = 0; c < b.length * 8; c += 8) { a[c >> 5] |= (b.charCodeAt(c / 8) & 255) << (c % 32) } return a }; function binl2rstr(b) { var a = ""; for (var c = 0; c < b.length * 32; c += 8) { a += String.fromCharCode((b[c >> 5] >>> (c % 32)) & 255) } return a }; function binl_md5(p, k) { p[k >> 5] |= 128 << ((k) % 32); p[(((k + 64) >>> 9) << 4) + 14] = k; var o = 1732584193; var n = -271733879; var m = -1732584194; var l = 271733878; for (var g = 0; g < p.length; g += 16) { var j = o; var h = n; var f = m; var e = l; o = md5_ff(o, n, m, l, p[g + 0], 7, -680876936); l = md5_ff(l, o, n, m, p[g + 1], 12, -389564586); m = md5_ff(m, l, o, n, p[g + 2], 17, 606105819); n = md5_ff(n, m, l, o, p[g + 3], 22, -1044525330); o = md5_ff(o, n, m, l, p[g + 4], 7, -176418897); l = md5_ff(l, o, n, m, p[g + 5], 12, 1200080426); m = md5_ff(m, l, o, n, p[g + 6], 17, -1473231341); n = md5_ff(n, m, l, o, p[g + 7], 22, -45705983); o = md5_ff(o, n, m, l, p[g + 8], 7, 1770035416); l = md5_ff(l, o, n, m, p[g + 9], 12, -1958414417); m = md5_ff(m, l, o, n, p[g + 10], 17, -42063); n = md5_ff(n, m, l, o, p[g + 11], 22, -1990404162); o = md5_ff(o, n, m, l, p[g + 12], 7, 1804603682); l = md5_ff(l, o, n, m, p[g + 13], 12, -40341101); m = md5_ff(m, l, o, n, p[g + 14], 17, -1502002290); n = md5_ff(n, m, l, o, p[g + 15], 22, 1236535329); o = md5_gg(o, n, m, l, p[g + 1], 5, -165796510); l = md5_gg(l, o, n, m, p[g + 6], 9, -1069501632); m = md5_gg(m, l, o, n, p[g + 11], 14, 643717713); n = md5_gg(n, m, l, o, p[g + 0], 20, -373897302); o = md5_gg(o, n, m, l, p[g + 5], 5, -701558691); l = md5_gg(l, o, n, m, p[g + 10], 9, 38016083); m = md5_gg(m, l, o, n, p[g + 15], 14, -660478335); n = md5_gg(n, m, l, o, p[g + 4], 20, -405537848); o = md5_gg(o, n, m, l, p[g + 9], 5, 568446438); l = md5_gg(l, o, n, m, p[g + 14], 9, -1019803690); m = md5_gg(m, l, o, n, p[g + 3], 14, -187363961); n = md5_gg(n, m, l, o, p[g + 8], 20, 1163531501); o = md5_gg(o, n, m, l, p[g + 13], 5, -1444681467); l = md5_gg(l, o, n, m, p[g + 2], 9, -51403784); m = md5_gg(m, l, o, n, p[g + 7], 14, 1735328473); n = md5_gg(n, m, l, o, p[g + 12], 20, -1926607734); o = md5_hh(o, n, m, l, p[g + 5], 4, -378558); l = md5_hh(l, o, n, m, p[g + 8], 11, -2022574463); m = md5_hh(m, l, o, n, p[g + 11], 16, 1839030562); n = md5_hh(n, m, l, o, p[g + 14], 23, -35309556); o = md5_hh(o, n, m, l, p[g + 1], 4, -1530992060); l = md5_hh(l, o, n, m, p[g + 4], 11, 1272893353); m = md5_hh(m, l, o, n, p[g + 7], 16, -155497632); n = md5_hh(n, m, l, o, p[g + 10], 23, -1094730640); o = md5_hh(o, n, m, l, p[g + 13], 4, 681279174); l = md5_hh(l, o, n, m, p[g + 0], 11, -358537222); m = md5_hh(m, l, o, n, p[g + 3], 16, -722521979); n = md5_hh(n, m, l, o, p[g + 6], 23, 76029189); o = md5_hh(o, n, m, l, p[g + 9], 4, -640364487); l = md5_hh(l, o, n, m, p[g + 12], 11, -421815835); m = md5_hh(m, l, o, n, p[g + 15], 16, 530742520); n = md5_hh(n, m, l, o, p[g + 2], 23, -995338651); o = md5_ii(o, n, m, l, p[g + 0], 6, -198630844); l = md5_ii(l, o, n, m, p[g + 7], 10, 1126891415); m = md5_ii(m, l, o, n, p[g + 14], 15, -1416354905); n = md5_ii(n, m, l, o, p[g + 5], 21, -57434055); o = md5_ii(o, n, m, l, p[g + 12], 6, 1700485571); l = md5_ii(l, o, n, m, p[g + 3], 10, -1894986606); m = md5_ii(m, l, o, n, p[g + 10], 15, -1051523); n = md5_ii(n, m, l, o, p[g + 1], 21, -2054922799); o = md5_ii(o, n, m, l, p[g + 8], 6, 1873313359); l = md5_ii(l, o, n, m, p[g + 15], 10, -30611744); m = md5_ii(m, l, o, n, p[g + 6], 15, -1560198380); n = md5_ii(n, m, l, o, p[g + 13], 21, 1309151649); o = md5_ii(o, n, m, l, p[g + 4], 6, -145523070); l = md5_ii(l, o, n, m, p[g + 11], 10, -1120210379); m = md5_ii(m, l, o, n, p[g + 2], 15, 718787259); n = md5_ii(n, m, l, o, p[g + 9], 21, -343485551); o = safe_add(o, j); n = safe_add(n, h); m = safe_add(m, f); l = safe_add(l, e) } return Array(o, n, m, l) }; function md5_cmn(h, e, d, c, g, f) { return safe_add(bit_rol(safe_add(safe_add(e, h), safe_add(c, f)), g), d) }; function md5_ff(g, f, k, j, e, i, h) { return md5_cmn((f & k) | ((~f) & j), g, f, e, i, h) }; function md5_gg(g, f, k, j, e, i, h) { return md5_cmn((f & j) | (k & (~j)), g, f, e, i, h) }; function md5_hh(g, f, k, j, e, i, h) { return md5_cmn(f ^ k ^ j, g, f, e, i, h) }; function md5_ii(g, f, k, j, e, i, h) { return md5_cmn(k ^ (f | (~j)), g, f, e, i, h) }; function safe_add(a, d) { var c = (a & 65535) + (d & 65535); var b = (a >> 16) + (d >> 16) + (c >> 16); return (b << 16) | (c & 65535) }; function bit_rol(a, b) { return (a << b) | (a >>> (32 - b)) }; ///////////////////////////////////////////////////// // 避免全局命名空间冲突 md5_func.noConflict = function publicAPI$noConflict() { if (context) { // 将那个 name还原回原来的对象 context[name] = old_public_api; } // 返回自身,由调用的代码自己持有,保存,或赋值给某个变量 return md5_func; }; // 返回的对象,会被绑定到 MD5 之类的名字上,在外部就引用了此对象, // 因为闭包特性,可以利用到闭包内部方法和内部对象。 lib一般都是利用这种闭包特性,维护私有的属性、对象, // 对外只暴露一些方法(API),也就是 function, 外面只能调用这些API,方便内部进行逻辑控制,降低依赖. return md5_func;})

测试结果:

md5("1");"c4ca4238a0b923820dcc509a6f75849b"md5(md5("1"))"28c8edde3d61a0411511d3b1866f0636"

4. Oracle 数据库版MD5

注意: 为了与在其他环境下的MD5方法一致,需要转换为小写
需要创建一个存储函数:

CREATE OR REPLACE FUNCTION MD5(passwd IN VARCHAR2) RETURN VARCHAR2 IS retval varchar2(32);BEGIN retval := Lower(utl_raw.cast_to_raw(DBMS_OBFUSCATION_TOOLKIT.MD5(INPUT_STRING => passwd))); RETURN retval;END;

测试结果:

SQL> select MD5('1') as m1, MD5(md5('1')) as m2 from dual 2 ;M1---------------------------------------M2---------------------------------------c4ca4238a0b923820dcc509a6f75849b28c8edde3d61a0411511d3b1866f0636

PS：这里再为大家提供2款MD5加密工具，感兴趣的朋友可以参考一下：

MD5在线加密工具：

http://tools.jb51.net/password/CreateMD5Password

在线MD5/hash/SHA-1/SHA-2/SHA-256/SHA-512/SHA-3/RIPEMD-160加密工具：

http://tools.jb51.net/password/hash_md5_sha