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Asked: 2026-06-18T01:31:46+00:00

The following code procedure bytes = parseHexString (createHexString (bytes)) leads to updated of bytes

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The following code procedure bytes = parseHexString (createHexString (bytes)) leads to updated of bytes, what I would like to avoid. And as a result calculations are not correct.

<html>
<head>
<SCRIPT SRC="http://eu.static.mega.co.nz/sjcl_1.js"></SCRIPT>
<SCRIPT SRC="http://eu.static.mega.co.nz/crypto_1.js"></SCRIPT>
<SCRIPT SRC="http://eu.static.mega.co.nz/rsa_1.js"></SCRIPT>
<SCRIPT SRC="http://eu.static.mega.co.nz/hex_1.js"></SCRIPT>
<SCRIPT>
function parseHexString(str) { 
    var result = [];
    while (str.length >= 2) { 
        result.push(parseInt(str.substring(0, 2), 16));
        str = str.substring(2, str.length);
    }

    return result;
}

function createHexString(arr) {
    var result = "";
    for (i in arr) {
        var str = arr[i].toString(16);
        str = str.length == 0 ? "00" :
              str.length == 1 ? "0" + str : 
              str.length == 2 ? str :
              str.substring(str.length-2, str.length);
        result += str;
    }
    return result;
}

function t()
{
    var json_k     = 'aOrP5yLtNQT53WMQfufSlA';
    var json_csid  = 'CABD6JUMldvI_eqP0537xl9P8x7kgk2OjOq99Fy7kosphj6AFUtlbwRRDpg4EIifXRLO6FNpdD22WwtUlJ_1Mgye2Y87trEqLCbhahuEFJVQNMDtNbIem7xY2ER9uF-cdgBXZWuzp7XIBybSh7W8MSUlv_eGS6LcLGJ81Q49dSzVhcswHTJ_IJl04p3c0axR6ZIJ8dH5bJ_vXvgQsypUVVtdfMacKhB9cXdEtRZ6iWLKCKqscXdo6CNXlbIdzRhro0gxfmhfB_miysFAiSQrbtuYnIgYBU3i9p3jRlPD4ti3CUcnj0SomV61w1aEYNvo56HPMUZlVkVHA7BFzvHGHo0J';
    var json_privk = 'K7LDtk2M2QhjJx_v_Hqf0LKUBaZx76U_vBDjQty9HpFDy2MntF5HxxuyHQ9-1HmXeYzbL1pZnAxsZ7LRUbDnkR6qtJVaGdWuQhrytkuq0l5zBp-O--gZxoQPRGTsVgVRdAvpsRTkQI_q8fxADLCe0womFxtvvnD_FJgjaMsm7vkYchXkoq33WWyHijb3JMkymjl0_GtiSamT0qEL6sm_l5Z1lehqBGUEHfYAa0ub8IDx_yqy2R9Nh8Lwzmz4s24sShVxjaNsMBlSE-sEvTziOsnNWK1Zl_XUYadlENkweuIoxYx_lt8XIV71TzjEFuVTd-pXhzVlqePmIu3SM3bO1Kzq_DnGfB62RmzlmbtHU4iyw4Hd1wQFRhTeSRrvMjsMPFKN-SIIQU7CRNaMuaDxZbNZcOKhMg_h9mApM0rRS3VZaGZzFTL9rSaDMYHw4pL3aOkSFPMY3w785Tss7Zqwuo9HFUWUVbnYAb97JkgCohlMotORrMMtual1dQ4sG1sIYXyWTckAGGL0ZAGurhtSKiyz1m8Lb39pXPacqFh_nCHqqb2_RdrKTj0PdGZESKkU8YedeqC1I9nR4v38DuQc-pBBR5DOwgNjJMvzvsUehs_PxIL8THjgIcr7ONc4hWV9o2v_l81Vo2cCW2I99Iz84IFN2fV1dTqHIG_tnLzz8ljBVygETUqrFdZ0JlQJkurZ7RBku5krm-k9CZmDezCIzPPil-RcYzVIk00gNYAxfiZE48Or4WEiGjgKLnHCYVtSlvlMF4bPGB4SVCZ-68j49EjfSWaMK0OoMkpGhqf7KchgxYBZq6o3AhLgp4t0BClvsdee6VTz1SFqc3m2A-TMG6fNdbCT_Q9nYCYdZIROdOc';

    var aes = new sjcl.cipher.aes( prepare_key_pw("oEyoo9cQcw") );
    k = decrypt_key(aes, base64_to_a32(json_k) );

    aes = new sjcl.cipher.aes(k);

    var t = mpi2b(base64urldecode(json_csid));

    var privk = a32_to_str(decrypt_key(aes,base64_to_a32(json_privk)));

    var rsa_privk = Array(4);
    for (var i = 0; i < 4; i++)
    {
        var l = ((privk.charCodeAt(0)*256+privk.charCodeAt(1)+7)>>3)+2;

        rsa_privk[i] = mpi2b(privk.substr(0,l));
        if (typeof rsa_privk[i] == 'number') break;
        privk = privk.substr(l);    
    }

    var p = parseHexString(createHexString(rsa_privk[0]));  // !!!!!!!!!!!!!!!!!!!!!!!!!!!!
    var q = parseHexString(createHexString(rsa_privk[1]));  // !!!!!!!!!!!!!!!!!!!!!!!!!!!!
    var d = parseHexString(createHexString(rsa_privk[2]));  // !!!!!!!!!!!!!!!!!!!!!!!!!!!!
    var u = parseHexString(createHexString(rsa_privk[3]));  // !!!!!!!!!!!!!!!!!!!!!!!!!!!!
    sid = base64urlencode(b2s(RSAdecrypt(t,d,p,q,u)).substr(0,43));
    if (sid!=='tajetAbW0qTQGFlwp8iD5lQ0TFV1QUZJZFVvjRX7Xx-bPzYBoau7qog09w')
        console.log("ERROR");

    p = rsa_privk[0];
    q = rsa_privk[1];
    d = rsa_privk[2];
    u = rsa_privk[3];
    sid = base64urlencode(b2s(RSAdecrypt(t,d,p,q,u)).substr(0,43));
    if (sid=='tajetAbW0qTQGFlwp8iD5lQ0TFV1QUZJZFVvjRX7Xx-bPzYBoau7qog09w')
        console.log("OK");
}
</script>

</head>
<body onload="t();"></body>
</html>

I am not javascript developer, and not one found in google code did not work on this data.

Update 1

console.log(createHexString(rsa_privk[0])); = e5d109c673d8ef03df564beb9e36e9983a23842b0a724efa45ff76bbe5ad72ed62d2757968

But if do 

parseHexString('e5d109c673d8ef03df564beb9e36e9983a23842b0a724efa45ff76bbe5ad72ed‌​62d2757968');

then code if (sid!== ... make error

Update 2

console.log(rsa_privk[0].toString(16));

output:
123676133,198914513,129998601,245147334,11918451,206998232,96766191,75984899,177840095,106709334,10180427,208237547,119814814,127003446,189062377,84099480,220452154,250519075,267883908,115471915,165124106,238628722,169382478,42320122,95982405,80725759,89608310,85166267,200925925,254033325,86971506,191278317,127411298,180195794,142776693,188738169,39016

Update 3

console.log(parseHexString(createHexString(rsa_privk[0])));
console.log(rsa_privk[0]);

output:

[229, 209, 9, 198, 115, 216, 239, 3, 223, 86, 75, 235, 158, 54, 233, 152, 58, 35, 132, 43, 10, 114, 78, 250, 69, 255, 118, 187, 229, 173, 114, 237, 98, 210, 117, 121, 104]

[123676133, 198914513, 129998601, 245147334, 11918451, 206998232, 96766191, 75984899, 177840095, 106709334, 10180427, 208237547, 119814814, 127003446, 189062377, 84099480, 220452154, 250519075, 267883908, 115471915, 165124106, 238628722, 169382478, 42320122, 95982405, 80725759, 89608310, 85166267, 200925925, 254033325, 86971506, 191278317, 127411298, 180195794, 142776693, 188738169, 39016]
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1 Answer

  1. Editorial Team

    Update: Scroll down for solution… Live Demo

    The issue: you are using a lossy conversion to hex, which cannot be reversed.

    var p = parseHexString(createHexString(rsa_privk[0]));

    This will never be same as rsa_privk[0].

    Because, createHexString() only uses the last 2 bytes from each array element.

    Example:

    rsa_privk[0] : [123676133, 198914513, 129998601, 245147334, 11918451, 206998232, 96766191, 75984899, 177840095, 106709334, 10180427, 208237547, 119814814, 127003446, 189062377, 84099480, 220452154, 250519075, 267883908, 115471915, 165124106, 238628722, 169382478, 42320122, 95982405, 80725759, 89608310, 85166267, 200925925, 254033325, 86971506, 191278317, 127411298, 180195794, 142776693, 188738169, 39016]

createHexString(rsa_privk[0]) : e5d109c673d8ef03df564beb9e36e9983a23842b0a724efa45ff76bbe5ad72ed62d2757968

parseHexString(createHexString(rsa_privk[0])) : [229, 209, 9, 198, 115, 216, 239, 3, 223, 86, 75, 235, 158, 54, 233, 152, 58, 35, 132, 43, 10, 114, 78, 250, 69, 255, 118, 187, 229, 173, 114, 237, 98, 210, 117, 121, 104]

    Update : Working Solution…

    The two functions… the hex always contains 8 byte blocks, each for each element in the array…

    function parseHexString(str) { 
    var result = [];
    while (str.length >= 8) { 
        result.push(parseInt(str.substring(0, 8), 16));

        str = str.substring(8, str.length);
    }

    return result;
}

function createHexString(arr) {
    var result = "";
    var z;

    for (var i = 0; i < arr.length; i++) {
        var str = arr[i].toString(16);

        z = 8 - str.length + 1;
        str = Array(z).join("0") + str;

        result += str;
    }

    return result;
}

    Test code…

    function test() {   
    a = [123676133, 198914513, 129998601, 245147334, 11918451, 206998232, 96766191, 75984899, 177840095, 106709334, 10180427, 208237547, 119814814, 127003446, 189062377, 84099480, 220452154, 250519075, 267883908, 115471915, 165124106, 238628722, 169382478, 42320122, 95982405, 80725759, 89608310, 85166267, 200925925, 254033325, 86971506, 191278317, 127411298, 180195794, 142776693, 188738169, 39016];

    console.log("Input");
    console.log(a);

    b = createHexString(a);

    console.log("Hex");
    console.log(b);

    c = parseHexString(b); 

    console.log("Output");
    console.log(c);

    if(checkIfEqual(a, c)) {
        alert("Same");
    }
}

function checkIfEqual(arr1, arr2) {
    if (arr1.length != arr2.length) {
        return false;
    }
    //sort them first, then join them and just compare the strings
    return arr1.sort().join() == arr2.sort().join();
}
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