via view-source:http://www.zibri.org/2015/10/tp-link-configuration-file-encrypt-and-decrypt.html

tplink_decrypt.js

String.prototype.hexEncode=function(){var a,b,c="";for(b=0;b<this.length;b++)a=this.charCodeAt(b).toString(16),c+=("00"+a).slice(-2);return c};String.prototype.hexDecode=function(){var a,b=this.match(/.{1,2}/g)||[],c="";for(a=0;a<b.length;a++)c+=String.fromCharCode(parseInt(b[a],16));return c};
function handleFileSelect(a){a.stopPropagation();a.preventDefault();var b=[];files="undefined"!=typeof a.dataTransfer?a.dataTransfer.files:a.target.files;for(a=findex=0;f=files[a];a++){var c=new FileReader;c.onloadend=function(a){ffile=a.target.result;k=CryptoJS.enc.Utf8.parse((location.host.split(".")[1]+location.host.split(".")[2]).replace(".",""));k.words[0]^=1038403449;k.words[1]^=-1869832024;if(files[findex].name.toLowerCase().lastIndexOf(".bin")==files[findex].name.length-4){a=files[findex].name.substring(0,
files[findex].name.length-4)+".cfg";var b=CryptoJS.DES.decrypt(btoa(ffile),k,{mode:CryptoJS.mode.ECB,padding:CryptoJS.pad.ZeroPadding});encfile=b.toString(CryptoJS.enc.Base64);fmd5=CryptoJS.MD5(atob(encfile).substring(16)).toString(CryptoJS.enc.Hex);imd5=atob(encfile).substring(0,16).hexEncode();console.log("MD5 = 0x"+fmd5.toUpperCase());fmd5==imd5?console.log("MD5 is correct."):console.log("MD5 is NOT correct.");encfile=btoa(atob(encfile).substring(16))}else a=files[findex].name.substring(0,files[findex].name.length-
4)+".bin",fmd5=CryptoJS.MD5(ffile).toString(CryptoJS.enc.Hex),ffile=fmd5.hexDecode()+ffile,console.log("MD5 = 0x"+fmd5.toUpperCase()),b=CryptoJS.DES.encrypt(CryptoJS.enc.Latin1.parse(ffile),k,{mode:CryptoJS.mode.ECB,padding:CryptoJS.pad.ZeroPadding}),encfile=b.toString();zz=document.createElement("a");zz.setAttribute("download",a);zz.href="data:application/octet-stream;base64,"+encfile;a=document.createEvent("MouseEvents");a.initEvent("click",!1,!0);zz.dispatchEvent(a);findex++};c.readAsBinaryString(f);
b.push("<li><strong>",f.name,"</strong> (",f.type||"n/a",") - ",f.size," bytes, last modified: ",f.lastModifiedDate?f.lastModifiedDate.toLocaleDateString():"n/a","</li>")}document.getElementById("list").innerHTML="<ul>"+b.join("")+"</ul>"}function handleDragOver(a){a.stopPropagation();a.preventDefault();a.dataTransfer.dropEffect="copy"}var dropZone=document.getElementById("drop_zone");dropZone.addEventListener("dragover",handleDragOver,!1);dropZone.addEventListener("drop",handleFileSelect,!1);
dropZone.addEventListener("change",handleFileSelect,!1);

tplink_decrypt_pretty.js

String.prototype.hexEncode = function() {
    var a, b, c = "";
    for (b = 0; b < this.length; b++) a = this.charCodeAt(b).toString(16), c += ("00" + a).slice(-2);
    return c
};
String.prototype.hexDecode = function() {
    var a, b = this.match(/.{1,2}/g) || [],
        c = "";
    for (a = 0; a < b.length; a++) c += String.fromCharCode(parseInt(b[a], 16));
    return c
};

function handleFileSelect(a) {
    a.stopPropagation();
    a.preventDefault();
    var b = [];
    files = "undefined" != typeof a.dataTransfer ? a.dataTransfer.files : a.target.files;
    for (a = findex = 0; f = files[a]; a++) {
        var c = new FileReader;
        c.onloadend = function(a) {
            ffile = a.target.result;
            k = CryptoJS.enc.Utf8.parse((location.host.split(".")[1] + location.host.split(".")[2]).replace(".", ""));
            k.words[0] ^= 1038403449;
            k.words[1] ^= -1869832024;
            if (files[findex].name.toLowerCase().lastIndexOf(".bin") == files[findex].name.length - 4) {
                a = files[findex].name.substring(0,
                    files[findex].name.length - 4) + ".cfg";
                var b = CryptoJS.DES.decrypt(btoa(ffile), k, {
                    mode: CryptoJS.mode.ECB,
                    padding: CryptoJS.pad.ZeroPadding
                });
                encfile = b.toString(CryptoJS.enc.Base64);
                fmd5 = CryptoJS.MD5(atob(encfile).substring(16)).toString(CryptoJS.enc.Hex);
                imd5 = atob(encfile).substring(0, 16).hexEncode();
                console.log("MD5 = 0x" + fmd5.toUpperCase());
                fmd5 == imd5 ? console.log("MD5 is correct.") : console.log("MD5 is NOT correct.");
                encfile = btoa(atob(encfile).substring(16))
            } else a = files[findex].name.substring(0, files[findex].name.length -
                4) + ".bin", fmd5 = CryptoJS.MD5(ffile).toString(CryptoJS.enc.Hex), ffile = fmd5.hexDecode() + ffile, console.log("MD5 = 0x" + fmd5.toUpperCase()), b = CryptoJS.DES.encrypt(CryptoJS.enc.Latin1.parse(ffile), k, {
                mode: CryptoJS.mode.ECB,
                padding: CryptoJS.pad.ZeroPadding
            }), encfile = b.toString();
            zz = document.createElement("a");
            zz.setAttribute("download", a);
            zz.href = "data:application/octet-stream;base64," + encfile;
            a = document.createEvent("MouseEvents");
            a.initEvent("click", !1, !0);
            zz.dispatchEvent(a);
            findex++
        };
        c.readAsBinaryString(f);
        b.push("<li><strong>", f.name, "</strong> (", f.type || "n/a", ") - ", f.size, " bytes, last modified: ", f.lastModifiedDate ? f.lastModifiedDate.toLocaleDateString() : "n/a", "</li>")
    }
    document.getElementById("list").innerHTML = "<ul>" + b.join("") + "</ul>"
}

function handleDragOver(a) {
    a.stopPropagation();
    a.preventDefault();
    a.dataTransfer.dropEffect = "copy"
}
var dropZone = document.getElementById("drop_zone");
dropZone.addEventListener("dragover", handleDragOver, !1);
dropZone.addEventListener("drop", handleFileSelect, !1);
dropZone.addEventListener("change", handleFileSelect, !1);