Trong khi vọc vạch trang web trường, mình tìm được đoạn code xử lý chuỗi thành chuỗi mã hóa MD5 khá thú vị. Cụ thể trang web trường sử dụng nó để mã hóa mật khẩu sinh viên sau đó mới gửi về server. Mình không rõ là ở phía back-end có mã hóa nữa hay không.
Đây là code mình tìm được:
var MD5 = function (string) {
function RotateLeft(lValue, iShiftBits) {
return (lValue << iShiftBits) | (lValue >>> (32 - iShiftBits));
}
function AddUnsigned(lX, lY) {
var lX4, lY4, lX8, lY8, lResult;
lX8 = (lX & 0x80000000);
lY8 = (lY & 0x80000000);
lX4 = (lX & 0x40000000);
lY4 = (lY & 0x40000000);
lResult = (lX & 0x3FFFFFFF) + (lY & 0x3FFFFFFF);
if (lX4 & lY4) {
return (lResult ^ 0x80000000 ^ lX8 ^ lY8);
}
if (lX4 | lY4) {
if (lResult & 0x40000000) {
return (lResult ^ 0xC0000000 ^ lX8 ^ lY8);
} else {
return (lResult ^ 0x40000000 ^ lX8 ^ lY8);
}
} else {
return (lResult ^ lX8 ^ lY8);
}
}
function F(x, y, z) { return (x & y) | ((~x) & z); }
function G(x, y, z) { return (x & z) | (y & (~z)); }
function H(x, y, z) { return (x ^ y ^ z); }
function I(x, y, z) { return (y ^ (x | (~z))); }
function FF(a, b, c, d, x, s, ac) {
a = AddUnsigned(a, AddUnsigned(AddUnsigned(F(b, c, d), x), ac));
return AddUnsigned(RotateLeft(a, s), b);
};
function GG(a, b, c, d, x, s, ac) {
a = AddUnsigned(a, AddUnsigned(AddUnsigned(G(b, c, d), x), ac));
return AddUnsigned(RotateLeft(a, s), b);
};
function HH(a, b, c, d, x, s, ac) {
a = AddUnsigned(a, AddUnsigned(AddUnsigned(H(b, c, d), x), ac));
return AddUnsigned(RotateLeft(a, s), b);
};
function II(a, b, c, d, x, s, ac) {
a = AddUnsigned(a, AddUnsigned(AddUnsigned(I(b, c, d), x), ac));
return AddUnsigned(RotateLeft(a, s), b);
};
function ConvertToWordArray(string) {
var lWordCount;
var lMessageLength = string.length;
var lNumberOfWords_temp1 = lMessageLength + 8;
var lNumberOfWords_temp2 = (lNumberOfWords_temp1 - (lNumberOfWords_temp1 % 64)) / 64;
var lNumberOfWords = (lNumberOfWords_temp2 + 1) * 16;
var lWordArray = Array(lNumberOfWords - 1);
var lBytePosition = 0;
var lByteCount = 0;
while (lByteCount < lMessageLength) {
lWordCount = (lByteCount - (lByteCount % 4)) / 4;
lBytePosition = (lByteCount % 4) * 8;
lWordArray[lWordCount] = (lWordArray[lWordCount] | (string.charCodeAt(lByteCount) << lBytePosition));
lByteCount++;
}
lWordCount = (lByteCount - (lByteCount % 4)) / 4;
lBytePosition = (lByteCount % 4) * 8;
lWordArray[lWordCount] = lWordArray[lWordCount] | (0x80 << lBytePosition);
lWordArray[lNumberOfWords - 2] = lMessageLength << 3;
lWordArray[lNumberOfWords - 1] = lMessageLength >>> 29;
return lWordArray;
};
function WordToHex(lValue) {
var WordToHexValue = "", WordToHexValue_temp = "", lByte, lCount;
for (lCount = 0; lCount <= 3; lCount++) {
lByte = (lValue >>> (lCount * 8)) & 255;
WordToHexValue_temp = "0" + lByte.toString(16);
WordToHexValue = WordToHexValue + WordToHexValue_temp.substr(WordToHexValue_temp.length - 2, 2);
}
return WordToHexValue;
};
function Utf8Encode(string) {
string = string.replace(/\r\n/g, "\n");
var utftext = "";
for (var n = 0; n < string.length; n++) {
var c = string.charCodeAt(n);
if (c < 128) {
utftext += String.fromCharCode(c);
}
else if ((c > 127) && (c < 2048)) {
utftext += String.fromCharCode((c >> 6) | 192);
utftext += String.fromCharCode((c & 63) | 128);
}
else {
utftext += String.fromCharCode((c >> 12) | 224);
utftext += String.fromCharCode(((c >> 6) & 63) | 128);
utftext += String.fromCharCode((c & 63) | 128);
}
}
return utftext;
};
var x = Array();
var k, AA, BB, CC, DD, a, b, c, d;
var S11 = 7, S12 = 12, S13 = 17, S14 = 22;
var S21 = 5, S22 = 9, S23 = 14, S24 = 20;
var S31 = 4, S32 = 11, S33 = 16, S34 = 23;
var S41 = 6, S42 = 10, S43 = 15, S44 = 21;
string = Utf8Encode(string);
x = ConvertToWordArray(string);
a = 0x67452301; b = 0xEFCDAB89; c = 0x98BADCFE; d = 0x10325476;
for (k = 0; k < x.length; k += 16) {
AA = a; BB = b; CC = c; DD = d;
a = FF(a, b, c, d, x[k + 0], S11, 0xD76AA478);
d = FF(d, a, b, c, x[k + 1], S12, 0xE8C7B756);
c = FF(c, d, a, b, x[k + 2], S13, 0x242070DB);
b = FF(b, c, d, a, x[k + 3], S14, 0xC1BDCEEE);
a = FF(a, b, c, d, x[k + 4], S11, 0xF57C0FAF);
d = FF(d, a, b, c, x[k + 5], S12, 0x4787C62A);
c = FF(c, d, a, b, x[k + 6], S13, 0xA8304613);
b = FF(b, c, d, a, x[k + 7], S14, 0xFD469501);
a = FF(a, b, c, d, x[k + 8], S11, 0x698098D8);
d = FF(d, a, b, c, x[k + 9], S12, 0x8B44F7AF);
c = FF(c, d, a, b, x[k + 10], S13, 0xFFFF5BB1);
b = FF(b, c, d, a, x[k + 11], S14, 0x895CD7BE);
a = FF(a, b, c, d, x[k + 12], S11, 0x6B901122);
d = FF(d, a, b, c, x[k + 13], S12, 0xFD987193);
c = FF(c, d, a, b, x[k + 14], S13, 0xA679438E);
b = FF(b, c, d, a, x[k + 15], S14, 0x49B40821);
a = GG(a, b, c, d, x[k + 1], S21, 0xF61E2562);
d = GG(d, a, b, c, x[k + 6], S22, 0xC040B340);
c = GG(c, d, a, b, x[k + 11], S23, 0x265E5A51);
b = GG(b, c, d, a, x[k + 0], S24, 0xE9B6C7AA);
a = GG(a, b, c, d, x[k + 5], S21, 0xD62F105D);
d = GG(d, a, b, c, x[k + 10], S22, 0x2441453);
c = GG(c, d, a, b, x[k + 15], S23, 0xD8A1E681);
b = GG(b, c, d, a, x[k + 4], S24, 0xE7D3FBC8);
a = GG(a, b, c, d, x[k + 9], S21, 0x21E1CDE6);
d = GG(d, a, b, c, x[k + 14], S22, 0xC33707D6);
c = GG(c, d, a, b, x[k + 3], S23, 0xF4D50D87);
b = GG(b, c, d, a, x[k + 8], S24, 0x455A14ED);
a = GG(a, b, c, d, x[k + 13], S21, 0xA9E3E905);
d = GG(d, a, b, c, x[k + 2], S22, 0xFCEFA3F8);
c = GG(c, d, a, b, x[k + 7], S23, 0x676F02D9);
b = GG(b, c, d, a, x[k + 12], S24, 0x8D2A4C8A);
a = HH(a, b, c, d, x[k + 5], S31, 0xFFFA3942);
d = HH(d, a, b, c, x[k + 8], S32, 0x8771F681);
c = HH(c, d, a, b, x[k + 11], S33, 0x6D9D6122);
b = HH(b, c, d, a, x[k + 14], S34, 0xFDE5380C);
a = HH(a, b, c, d, x[k + 1], S31, 0xA4BEEA44);
d = HH(d, a, b, c, x[k + 4], S32, 0x4BDECFA9);
c = HH(c, d, a, b, x[k + 7], S33, 0xF6BB4B60);
b = HH(b, c, d, a, x[k + 10], S34, 0xBEBFBC70);
a = HH(a, b, c, d, x[k + 13], S31, 0x289B7EC6);
d = HH(d, a, b, c, x[k + 0], S32, 0xEAA127FA);
c = HH(c, d, a, b, x[k + 3], S33, 0xD4EF3085);
b = HH(b, c, d, a, x[k + 6], S34, 0x4881D05);
a = HH(a, b, c, d, x[k + 9], S31, 0xD9D4D039);
d = HH(d, a, b, c, x[k + 12], S32, 0xE6DB99E5);
c = HH(c, d, a, b, x[k + 15], S33, 0x1FA27CF8);
b = HH(b, c, d, a, x[k + 2], S34, 0xC4AC5665);
a = II(a, b, c, d, x[k + 0], S41, 0xF4292244);
d = II(d, a, b, c, x[k + 7], S42, 0x432AFF97);
c = II(c, d, a, b, x[k + 14], S43, 0xAB9423A7);
b = II(b, c, d, a, x[k + 5], S44, 0xFC93A039);
a = II(a, b, c, d, x[k + 12], S41, 0x655B59C3);
d = II(d, a, b, c, x[k + 3], S42, 0x8F0CCC92);
c = II(c, d, a, b, x[k + 10], S43, 0xFFEFF47D);
b = II(b, c, d, a, x[k + 1], S44, 0x85845DD1);
a = II(a, b, c, d, x[k + 8], S41, 0x6FA87E4F);
d = II(d, a, b, c, x[k + 15], S42, 0xFE2CE6E0);
c = II(c, d, a, b, x[k + 6], S43, 0xA3014314);
b = II(b, c, d, a, x[k + 13], S44, 0x4E0811A1);
a = II(a, b, c, d, x[k + 4], S41, 0xF7537E82);
d = II(d, a, b, c, x[k + 11], S42, 0xBD3AF235);
c = II(c, d, a, b, x[k + 2], S43, 0x2AD7D2BB);
b = II(b, c, d, a, x[k + 9], S44, 0xEB86D391);
a = AddUnsigned(a, AA);
b = AddUnsigned(b, BB);
c = AddUnsigned(c, CC);
d = AddUnsigned(d, DD);
}
var temp = WordToHex(a) + WordToHex(b) + WordToHex(c) + WordToHex(d);
return temp.toLowerCase();
}Cách sử dụng:
var strHash = MD5("text");