[p][b]首先说说md5：[/b][/p] [p]md5用的是哈希函数,在计算机网络中应用较多的不可逆加密算法有rsa公司发明的md5算法和由美国国家技术标准研究所建议的安全散列算法sha.[br][i]虽说已经被破解（见[/i][url=http://baike.baidu.com/view/7636.htm][i]百度百科[/i][/url][i]），但仍然是我们的加密首选。[/i][/p] [p][b]说说用js md5加密的优点：[/b][/p] [p]由于表单(form)在提交的时候，无论是通过get方法还是通过post方法，密码在提交时都会以明码的方式进行发送，很不安全。如果不是在ssl下传输的数据比较容易被分析出表单提交的密码。[br]优点：[br]1、如上所述，增加了安全性，[br]2、用javascript在客户端来加密可以减少服务器端的运算。[/p] [p]这是[url=http://pajhome.org.uk/crypt/md5/]md5的js加密代码的demo[/url]。其中也有md4和sha1的js加密代码。原页面也又包含js的用法[/p] [p]代码：[/p] [p]md5.js[/p] view plaincopy to clipboardprint? /* * a javascript implementation of the rsa data security, inc. md5 message * digest algorithm, as defined in rfc 1321. * version 2.1 copyright (c) paul johnston 1999 - 2002. * other contributors: greg holt, andrew kepert, ydnar, lostinet * distributed under the bsd license * see http://pajhome.org.uk/crypt/md5 for more info. */ var hexcase = 0; var b64pad = ""; var chrsz = 8; function hex_md5(s){ return binl2hex(core_md5(str2binl(s), s.length * chrsz));} function b64_md5(s){ return binl2b64(core_md5(str2binl(s), s.length * chrsz));} function str_md5(s){ return binl2str(core_md5(str2binl(s), s.length * chrsz));} function hex_hmac_md5(key, data) { return binl2hex(core_hmac_md5(key, data)); } function b64_hmac_md5(key, data) { return binl2b64(core_hmac_md5(key, data)); } function str_hmac_md5(key, data) { return binl2str(core_hmac_md5(key, data)); } function md5_vm_test() { return hex_md5("abc") == "900150983cd24fb0d6963f7d28e17f72"; } function core_md5(x, len) { x[len >> 5] |= 0x80 < < ((len) % 32); x[(((len + 64) >>> 9) < < 4) + 14] = len; var a = 1732584193; var b = -271733879; var c = -1732584194; var d = 271733878; for(var i = 0; i < x.length; i += 16) { var olda = a; var oldb = b; var oldc = c; var oldd = d; a = md5_ff(a, b, c, d, x[i+ 0], 7 , -680876936); d = md5_ff(d, a, b, c, x[i+ 1], 12, -389564586); c = md5_ff(c, d, a, b, x[i+ 2], 17, 606105819); b = md5_ff(b, c, d, a, x[i+ 3], 22, -1044525330); a = md5_ff(a, b, c, d, x[i+ 4], 7 , -176418897); d = md5_ff(d, a, b, c, x[i+ 5], 12, 1200080426); c = md5_ff(c, d, a, b, x[i+ 6], 17, -1473231341); b = md5_ff(b, c, d, a, x[i+ 7], 22, -45705983); a = md5_ff(a, b, c, d, x[i+ 8], 7 , 1770035416); d = md5_ff(d, a, b, c, x[i+ 9], 12, -1958414417); c = md5_ff(c, d, a, b, x[i+10], 17, -42063); b = md5_ff(b, c, d, a, x[i+11], 22, -1990404162); a = md5_ff(a, b, c, d, x[i+12], 7 , 1804603682); d = md5_ff(d, a, b, c, x[i+13], 12, -40341101); c = md5_ff(c, d, a, b, x[i+14], 17, -1502002290); b = md5_ff(b, c, d, a, x[i+15], 22, 1236535329); a = md5_gg(a, b, c, d, x[i+ 1], 5 , -165796510); d = md5_gg(d, a, b, c, x[i+ 6], 9 , -1069501632); c = md5_gg(c, d, a, b, x[i+11], 14, 643717713); b = md5_gg(b, c, d, a, x[i+ 0], 20, -373897302); a = md5_gg(a, b, c, d, x[i+ 5], 5 , -701558691); d = md5_gg(d, a, b, c, x[i+10], 9 , 38016083); c = md5_gg(c, d, a, b, x[i+15], 14, -660478335); b = md5_gg(b, c, d, a, x[i+ 4], 20, -405537848); a = md5_gg(a, b, c, d, x[i+ 9], 5 , 568446438); d = md5_gg(d, a, b, c, x[i+14], 9 , -1019803690); c = md5_gg(c, d, a, b, x[i+ 3], 14, -187363961); b = md5_gg(b, c, d, a, x[i+ 8], 20, 1163531501); a = md5_gg(a, b, c, d, x[i+13], 5 , -1444681467); d = md5_gg(d, a, b, c, x[i+ 2], 9 , -51403784); c = md5_gg(c, d, a, b, x[i+ 7], 14, 1735328473); b = md5_gg(b, c, d, a, x[i+12], 20, -1926607734); a = md5_hh(a, b, c, d, x[i+ 5], 4 , -378558); d = md5_hh(d, a, b, c, x[i+ 8], 11, -2022574463); c = md5_hh(c, d, a, b, x[i+11], 16, 1839030562); b = md5_hh(b, c, d, a, x[i+14], 23, -35309556); a = md5_hh(a, b, c, d, x[i+ 1], 4 , -1530992060); d = md5_hh(d, a, b, c, x[i+ 4], 11, 1272893353); c = md5_hh(c, d, a, b, x[i+ 7], 16, -155497632); b = md5_hh(b, c, d, a, x[i+10], 23, -1094730640); a = md5_hh(a, b, c, d, x[i+13], 4 , 681279174); d = md5_hh(d, a, b, c, x[i+ 0], 11, -358537222); c = md5_hh(c, d, a, b, x[i+ 3], 16, -722521979); b = md5_hh(b, c, d, a, x[i+ 6], 23, 76029189); a = md5_hh(a, b, c, d, x[i+ 9], 4 , -640364487); d = md5_hh(d, a, b, c, x[i+12], 11, -421815835); c = md5_hh(c, d, a, b, x[i+15], 16, 530742520); b = md5_hh(b, c, d, a, x[i+ 2], 23, -995338651); a = md5_ii(a, b, c, d, x[i+ 0], 6 , -198630844); d = md5_ii(d, a, b, c, x[i+ 7], 10, 1126891415); c = md5_ii(c, d, a, b, x[i+14], 15, -1416354905); b = md5_ii(b, c, d, a, x[i+ 5], 21, -57434055); a = md5_ii(a, b, c, d, x[i+12], 6 , 1700485571); d = md5_ii(d, a, b, c, x[i+ 3], 10, -1894986606); c = md5_ii(c, d, a, b, x[i+10], 15, -1051523); b = md5_ii(b, c, d, a, x[i+ 1], 21, -2054922799); a = md5_ii(a, b, c, d, x[i+ 8], 6 , 1873313359); d = md5_ii(d, a, b, c, x[i+15], 10, -30611744); c = md5_ii(c, d, a, b, x[i+ 6], 15, -1560198380); b = md5_ii(b, c, d, a, x[i+13], 21, 1309151649); a = md5_ii(a, b, c, d, x[i+ 4], 6 , -145523070); d = md5_ii(d, a, b, c, x[i+11], 10, -1120210379); c = md5_ii(c, d, a, b, x[i+ 2], 15, 718787259); b = md5_ii(b, c, d, a, x[i+ 9], 21, -343485551); a = safe_add(a, olda); b = safe_add(b, oldb); c = safe_add(c, oldc); d = safe_add(d, oldd); } return array(a, b, c, d); } function md5_cmn(q, a, b, x, s, t) { return safe_add(bit_rol(safe_add(safe_add(a, q), safe_add(x, t)), s),b); } function md5_ff(a, b, c, d, x, s, t) { return md5_cmn((b & c) | ((~b) & d), a, b, x, s, t); } function md5_gg(a, b, c, d, x, s, t) { return md5_cmn((b & d) | (c & (~d)), a, b, x, s, t); } function md5_hh(a, b, c, d, x, s, t) { return md5_cmn(b ^ c ^ d, a, b, x, s, t); } function md5_ii(a, b, c, d, x, s, t) { return md5_cmn(c ^ (b | (~d)), a, b, x, s, t); } function core_hmac_md5(key, data) { var bkey = str2binl(key); if(bkey.length > 16) bkey = core_md5(bkey, key.length * chrsz); var ipad = array(16), opad = array(16); for(var i = 0; i < 16; i++) { ipad[i] = bkey[i] ^ 0x36363636; opad[i] = bkey[i] ^ 0x5c5c5c5c; } var hash = core_md5(ipad.concat(str2binl(data)), 512 + data.length * chrsz); return core_md5(opad.concat(hash), 512 + 128); } function safe_add(x, y) { var lsw = (x & 0xffff) + (y & 0xffff); var msw = (x >> 16) + (y >> 16) + (lsw >> 16); return (msw < < 16) | (lsw & 0xffff); } function bit_rol(num, cnt) { return (num << cnt) | (num >>> (32 - cnt)); } function str2binl(str) { var bin = array(); var mask = (1 < < chrsz) - 1; for(var i = 0; i < str.length * chrsz; i += chrsz) bin[i>>5] |= (str.charcodeat(i / chrsz) & mask) < < (i%32); return bin; } function binl2str(bin) { var str = ""; var mask = (1 << chrsz) - 1; for(var i = 0; i < bin.length * 32; i += chrsz) str += string.fromcharcode((bin[i>>5] >>> (i % 32)) & mask); return str; } function binl2hex(binarray) { var hex_tab = hexcase ? "0123456789abcdef" : "0123456789abcdef"; var str = ""; for(var i = 0; i < binarray.length * 4; i++) { str += hex_tab.charat((binarray[i>>2] >> ((i%4)*8+4)) & 0xf) + hex_tab.charat((binarray[i>>2] >> ((i%4)*8 )) & 0xf); } return str; } function binl2b64(binarray) { var tab = "abcdefghijklmnopqrstuvwxyzabcdefghijklmnopqrstuvwxyz0123456789+/"; var str = ""; for(var i = 0; i < binarray.length * 4; i += 3) { var triplet = (((binarray[i >> 2] >> 8 * ( i %4)) & 0xff) < < 16) | (((binarray[i+1 >> 2] >> 8 * ((i+1)%4)) & 0xff) < < 8 ) | ((binarray[i+2 >> 2] >> 8 * ((i+2)%4)) & 0xff); for(var j = 0; j < 4; j++) { if(i * 8 + j * 6 > binarray.length * 32) str += b64pad; else str += tab.charat((triplet >> 6*(3-j)) & 0x3f); } } return str; } /* * a javascript implementation of the rsa data security, inc. md5 message * digest algorithm, as defined in rfc 1321. * version 2.1 copyright (c) paul johnston 1999 - 2002. * other contributors: greg holt, andrew kepert, ydnar, lostinet * distributed under the bsd license * see http://pajhome.org.uk/crypt/md5 for more info. */ var hexcase = 0; var b64pad = ""; var chrsz = 8; function hex_md5(s){ return binl2hex(core_md5(str2binl(s), s.length * chrsz));} function b64_md5(s){ return binl2b64(core_md5(str2binl(s), s.length * chrsz));} function str_md5(s){ return binl2str(core_md5(str2binl(s), s.length * chrsz));} function hex_hmac_md5(key, data) { return binl2hex(core_hmac_md5(key, data)); } function b64_hmac_md5(key, data) { return binl2b64(core_hmac_md5(key, data)); } function str_hmac_md5(key, data) { return binl2str(core_hmac_md5(key, data)); } function md5_vm_test() { return hex_md5("abc") == "900150983cd24fb0d6963f7d28e17f72"; } function core_md5(x, len) { x[len >> 5] |= 0x80 < < ((len) % 32); x[(((len + 64) >>> 9) < < 4) + 14] = len; var a = 1732584193; var b = -271733879; var c = -1732584194; var d = 271733878; for(var i = 0; i < x.length; i += 16) { var olda = a; var oldb = b; var oldc = c; var oldd = d; a = md5_ff(a, b, c, d, x[i+ 0], 7 , -680876936); d = md5_ff(d, a, b, c, x[i+ 1], 12, -389564586); c = md5_ff(c, d, a, b, x[i+ 2], 17, 606105819); b = md5_ff(b, c, d, a, x[i+ 3], 22, -1044525330); a = md5_ff(a, b, c, d, x[i+ 4], 7 , -176418897); d = md5_ff(d, a, b, c, x[i+ 5], 12, 1200080426); c = md5_ff(c, d, a, b, x[i+ 6], 17, -1473231341); b = md5_ff(b, c, d, a, x[i+ 7], 22, -45705983); a = md5_ff(a, b, c, d, x[i+ 8], 7 , 1770035416); d = md5_ff(d, a, b, c, x[i+ 9], 12, -1958414417); c = md5_ff(c, d, a, b, x[i+10], 17, -42063); b = md5_ff(b, c, d, a, x[i+11], 22, -1990404162); a = md5_ff(a, b, c, d, x[i+12], 7 , 1804603682); d = md5_ff(d, a, b, c, x[i+13], 12, -40341101); c = md5_ff(c, d, a, b, x[i+14], 17, -1502002290); b = md5_ff(b, c, d, a, x[i+15], 22, 1236535329); a = md5_gg(a, b, c, d, x[i+ 1], 5 , -165796510); d = md5_gg(d, a, b, c, x[i+ 6], 9 , -1069501632); c = md5_gg(c, d, a, b, x[i+11], 14, 643717713); b = md5_gg(b, c, d, a, x[i+ 0], 20, -373897302); a = md5_gg(a, b, c, d, x[i+ 5], 5 , -701558691); d = md5_gg(d, a, b, c, x[i+10], 9 , 38016083); c = md5_gg(c, d, a, b, x[i+15], 14, -660478335); b = md5_gg(b, c, d, a, x[i+ 4], 20, -405537848); a = md5_gg(a, b, c, d, x[i+ 9], 5 , 568446438); d = md5_gg(d, a, b, c, x[i+14], 9 , -1019803690); c = md5_gg(c, d, a, b, x[i+ 3], 14, -187363961); b = md5_gg(b, c, d, a, x[i+ 8], 20, 1163531501); a = md5_gg(a, b, c, d, x[i+13], 5 , -1444681467); d = md5_gg(d, a, b, c, x[i+ 2], 9 , -51403784); c = md5_gg(c, d, a, b, x[i+ 7], 14, 1735328473); b = md5_gg(b, c, d, a, x[i+12], 20, -1926607734); a = md5_hh(a, b, c, d, x[i+ 5], 4 , -378558); d = md5_hh(d, a, b, c, x[i+ 8], 11, -2022574463); c = md5_hh(c, d, a, b, x[i+11], 16, 1839030562); b = md5_hh(b, c, d, a, x[i+14], 23, -35309556); a = md5_hh(a, b, c, d, x[i+ 1], 4 , -1530992060); d = md5_hh(d, a, b, c, x[i+ 4], 11, 1272893353); c = md5_hh(c, d, a, b, x[i+ 7], 16, -155497632); b = md5_hh(b, c, d, a, x[i+10], 23, -1094730640); a = md5_hh(a, b, c, d, x[i+13], 4 , 681279174); d = md5_hh(d, a, b, c, x[i+ 0], 11, -358537222); c = md5_hh(c, d, a, b, x[i+ 3], 16, -722521979); b = md5_hh(b, c, d, a, x[i+ 6], 23, 76029189); a = md5_hh(a, b, c, d, x[i+ 9], 4 , -640364487); d = md5_hh(d, a, b, c, x[i+12], 11, -421815835); c = md5_hh(c, d, a, b, x[i+15], 16, 530742520); b = md5_hh(b, c, d, a, x[i+ 2], 23, -995338651); a = md5_ii(a, b, c, d, x[i+ 0], 6 , -198630844); d = md5_ii(d, a, b, c, x[i+ 7], 10, 1126891415); c = md5_ii(c, d, a, b, x[i+14], 15, -1416354905); b = md5_ii(b, c, d, a, x[i+ 5], 21, -57434055); a = md5_ii(a, b, c, d, x[i+12], 6 , 1700485571); d = md5_ii(d, a, b, c, x[i+ 3], 10, -1894986606); c = md5_ii(c, d, a, b, x[i+10], 15, -1051523); b = md5_ii(b, c, d, a, x[i+ 1], 21, -2054922799); a = md5_ii(a, b, c, d, x[i+ 8], 6 , 1873313359); d = md5_ii(d, a, b, c, x[i+15], 10, -30611744); c = md5_ii(c, d, a, b, x[i+ 6], 15, -1560198380); b = md5_ii(b, c, d, a, x[i+13], 21, 1309151649); a = md5_ii(a, b, c, d, x[i+ 4], 6 , -145523070); d = md5_ii(d, a, b, c, x[i+11], 10, -1120210379); c = md5_ii(c, d, a, b, x[i+ 2], 15, 718787259); b = md5_ii(b, c, d, a, x[i+ 9], 21, -343485551); a = safe_add(a, olda); b = safe_add(b, oldb); c = safe_add(c, oldc); d = safe_add(d, oldd); } return array(a, b, c, d); } function md5_cmn(q, a, b, x, s, t) { return safe_add(bit_rol(safe_add(safe_add(a, q), safe_add(x, t)), s),b); } function md5_ff(a, b, c, d, x, s, t) { return md5_cmn((b & c) | ((~b) & d), a, b, x, s, t); } function md5_gg(a, b, c, d, x, s, t) { return md5_cmn((b & d) | (c & (~d)), a, b, x, s, t); } function md5_hh(a, b, c, d, x, s, t) { return md5_cmn(b ^ c ^ d, a, b, x, s, t); } function md5_ii(a, b, c, d, x, s, t) { return md5_cmn(c ^ (b | (~d)), a, b, x, s, t); } function core_hmac_md5(key, data) { var bkey = str2binl(key); if(bkey.length > 16) bkey = core_md5(bkey, key.length * chrsz); var ipad = array(16), opad = array(16); for(var i = 0; i < 16; i++) { ipad[i] = bkey[i] ^ 0x36363636; opad[i] = bkey[i] ^ 0x5c5c5c5c; } var hash = core_md5(ipad.concat(str2binl(data)), 512 + data.length * chrsz); return core_md5(opad.concat(hash), 512 + 128); } function safe_add(x, y) { var lsw = (x & 0xffff) + (y & 0xffff); var msw = (x >> 16) + (y >> 16) + (lsw >> 16); return (msw < < 16) | (lsw & 0xffff); } function bit_rol(num, cnt) { return (num << cnt) | (num >>> (32 - cnt)); } function str2binl(str) { var bin = array(); var mask = (1 < < chrsz) - 1; for(var i = 0; i < str.length * chrsz; i += chrsz) bin[i>>5] |= (str.charcodeat(i / chrsz) & mask) < < (i%32); return bin; } function binl2str(bin) { var str