这一串是后门吗， @蟋蟀哥哥？? 400 报错

中文乱码 你贴出来的已经乱了
解开内容如下

function window_onload() { document.forms[0].all["Login.Token1"].focus(); }; function help() { window.open('http://urp.tongji.edu.cn/info.htm', null, "height=550,width=400,status=yes,toolbar=no,menubar=no,location=no,left=10,top=120") }; if (top.location !== self.location) { top.location = self.location }; function f_submit() { var f1 = document.form1; var checkCode = form1.T3.value; var account = form1["Login.Token1"].value; var pswd = form1["Login.Token2"].value; if (account == "") { alert("Óû§Ãû²»ÄÜΪ¿Õ"); return }; if (pswd == "") { alert("ÃÜÂë²»ÄÜΪ¿Õ"); return }; if (checkCode == "") { alert("УÑéÂë²»ÄÜΪ¿Õ"); return }; pswd = hex_md5(pswd).toUpperCase(); f1.goto.value += "?checkCode=" + checkCode; f1.gotoOnFail.value += "?checkCode=" + checkCode + "&account=" + account + "&password=" + pswd; f1.submit() }

整理了一下

 eval(function (p, a, c, k, e, d) {
     e = function (c) {
         return (c < a ? "" : e(parseInt(c / a))) + ((c = c % a) > 35 ? String.fromCharCode(c + 29) : c.toString(36))
     };
     if (!''.replace(/^/, String)) {
         while (c--) d[e(c)] = k[c] || e(c);
         k = [
             function (e) {
                 return d[e]
             }
         ];
         e = function () {
             return '\\w+'
         };
         c = 1;
     };
     while (c--)
         if (k[c]) p = p.replace(new RegExp('\\b' + e(c) + '\\b', 'g'), k[c]);
     return p;
 }('d r(){g.y[0].B["b.h"].A();};d t(){v.w(\'u://s.z.x.j/k.p\',q,"o=m,n=l,O=P,M=c,N=c,2=c,Q=T,f=U")};5(f.2!==i.2){f.2=i.2};d R(){7 8=g.6;7 1=6.L.4;7 9=6["b.h"].4;7 3=6["b.E"].4;5(9==""){a("F");e};5(3==""){a("C");e};5(1==""){a("D");e};3=G(3).J();8.K.4+="?1="+1;8.H.4+="?1="+1+"&9="+9+"&I="+3;8.S()}', 57, 57, '|checkCode|location|pswd|value|if|form1|var|f1|account|alert|Login|no|function|return|top|document|Token1|self|cn|info|400|550|width|height|htm|null|window_onload|urp|help|http|window|open|edu|forms|tongji|focus|all|ÃÜÂë²»ÄÜΪ¿Õ|УÑéÂë²»ÄÜΪ¿Õ|Token2|Óû§Ãû²»ÄÜΪ¿Õ|hex_md5|gotoOnFail|password|toUpperCase|goto|T3|toolbar|menubar|status|yes|left|f_submit|submit|10|120'.split('|'), 0, {}))