如何使用 Java 解码/解密 MD5 加密
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时间：2020-08-11 08:06:24 来源:igfitidea点击:
How to decode/decrypt MD5 encryption using Java
提问by error123456789
I am using the ExtJS framework. I have a MD5 function in JavaScriptto encrypt some JSON. My backend uses Java so I wanted to know how to decrypt an MD5 Javascript encryption using Java?
我正在使用 ExtJS 框架。我在JavaScript 中有一个 MD5 函数来加密一些 JSON。我的后端使用 Java，所以我想知道如何使用Java解密 MD5 Javascript 加密？
Here is the JS equiv of MD5 function that I am using:
这是我正在使用的 MD5 函数的 JS equiv：
Ext.util.MD5 = function(s,raw,hexcase,chrsz) {
raw = raw || false;
hexcase = hexcase || false;
chrsz = chrsz || 8;
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 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_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 [a, b, c, d];
}
function str2binl(str){
var bin = [];
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;
}
return (raw ? binl2str(core_md5(str2binl(s), s.length * chrsz)) : binl2hex(core_md5(str2binl(s), s.length * chrsz)) );
};
采纳答案by vsnyc
MD5 is a hash(i.e. one-way transformation), so you can't decrypt it. You can compare a known hash with hash computed from a cleartext to verify validity of input. Java has inbuilt library for this. I have used this code below, adapt as necessary, also verify that your hashes generated in javascript have the same encoding.
MD5 是一个散列（即单向转换），因此您无法对其进行解密。您可以将已知散列与从明文计算的散列进行比较，以验证输入的有效性。Java为此内置了库。我在下面使用了这段代码，根据需要进行了调整，还验证了您在 javascript 中生成的哈希值是否具有相同的编码。
import java.security.MessageDigest;
import sun.misc.BASE64Encoder;
public class MD5Sample {
/**
* Cipher for encode
*/
private final MessageDigest md;
public MD5Sample() throws SecurityException {
try {
md = MessageDigest.getInstance("MD5", "SUN");
}catch(Exception se) {
throw new SecurityException("In MD5 constructor " + se);
}
}
public String encode(String in) throws Exception {
if (in == null) {
return null;
}
try {
byte[] raw = null;
byte[] stringBytes = null;
stringBytes = in.getBytes("UTF8");
synchronized(md) {
raw = md.digest(stringBytes);
}
BASE64Encoder encoder = new BASE64Encoder();
return encoder.encode(raw);
} catch (Exception se) {
throw new Exception("Exception while encoding " + se);
}
}
public String decode(String in) {
throw new RuntimeException("NOT SUPPORTED");
}
/**
* Test harness
* @param args
*/
public static void main(String[] args) {
String clearText = "apple";
try {
MD5Sample app = new MD5Sample();
String encryptedHash = app.encode(clearText);
System.out.println(encryptedHash);
} catch (Exception e) {
e.printStackTrace();
}
}
}
