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diff --git a/lib/html_script_finder/dom_handler/dom_checker.js b/lib/html_script_finder/dom_handler/dom_checker.js
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+++ b/lib/html_script_finder/dom_handler/dom_checker.js
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+/**
+ * GNU LibreJS - A browser add-on to block nonfree nontrivial JavaScript.
+ * *
+ * Copyright (C) 2011, 2012, 2013, 2014 Loic J. Duros
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see  <http://www.gnu.org/licenses/>.
+ *
+ */
+
+/**
+ * dom_checker.js
+ * 
+ * checks scripts for nonfree/nontrivial.
+ * 
+ */
+
+var {Cc, Ci, Cu, Cm, Cr} = require("chrome");
+var timer = require("sdk/timers");
+
+var scriptProperties = require("html_script_finder/dom_handler/script_properties");
+const scriptTypes = scriptProperties.scriptTypes;
+const statusTypes = scriptProperties.statusTypes;
+const reasons = scriptProperties.reasons;
+
+// ensure xhr won't create an infinite loop
+// with html content.
+var urlTester = require("html_script_finder/url_seen_tester").urlSeenTester;
+var urlHandler = require("url_handler/url_handler");
+
+var privacyChecker = require("js_checker/privacy_checker").privacyCheck;
+var jsChecker = require("js_checker/js_checker");
+
+const types = require("js_checker/constant_types");
+var checkTypes = types.checkTypes;
+var stripCDATAOpen = /<\!\[CDATA\[/gi;
+var stripCDATAClose = /]]>/g;
+
+const getHash = require("script_entries/scripts_cache").scriptsCached.getHash;
+
+var DomChecker = function() {
+    // reference to domHandler instance
+    // using this object.
+    this.d = null;
+};
+
+/**
+ * init
+ * 
+ * assign a reference domHandler object
+ * to access/updates its properties.
+ * 
+ */
+DomChecker.prototype.init = function(domHandler) {
+    "use strict";
+
+    this.d = domHandler;
+};
+
+DomChecker.prototype.destroy = function() {
+    "use strict";
+
+    this.d = null;
+};
+
+/**
+ * checkAllInlineScripts
+ * 
+ * Sends all the inline/onpage scripts as a whole for a check and
+ * removes all scripts if nonfree nontrivial is found.
+ *
+ */
+DomChecker.prototype.checkAllInlineScripts = function() {
+    "use strict";
+
+    try {
+        var i = 0, len, script;
+
+        if (typeof this.d.inlineScripts !== 'undefined' &&
+                this.d.inlineScripts.length > 0
+        ) {
+            script = this.d.inlineScripts.shift();
+            console.debug("checking script for page",
+                    this.d.pageURL
+                    /*, JSON.stringify(script)*/);
+            if (this.d.removedAllScripts) {
+                // all js has already been removed.
+                // stop check.
+                console.debug("removed all");
+                return;
+            }
+
+            if (this.d.inlineJsFree === true) {
+                // add entry as accepted.
+                try {
+                    hash = getHash(script.text);
+                    script.tagAsAccepted(this.d.pageURL, reasons.FREE, hash);
+                } catch (e) {
+                    console.debug(e);
+                }
+            }
+
+            // even if page is free we need to check for allow trivial.
+            if (script.type === scriptTypes.INLINE) {
+                console.debug("analyzing script", script);
+                this.analyzeJs(script,
+                        script.text,
+                        this.checkSingleInlineScript.bind(this));
+            } else if (script.type === scriptTypes.ATTRIBUTE) {
+                console.debug("analyzing inline script", script);
+                this.analyzeJs(script,
+                        this.concatAttributes(script),
+                        this.checkSingleElementAttributes.bind(this));
+            }
+        } else {
+            // no more inline scripts. Switch to external scripts.
+            this.readyForExternal();
+        }
+    } catch (x) {
+        console.debug('checkAllInlineScripts error',
+                x, x.lineNumber, x.fileName);
+        this.readyForExternal();
+    }
+};
+
+DomChecker.prototype.concatAttributes = function(script) {
+    "use strict";
+    var i = 0,
+        le = script.jsAttributes.length,
+        text = "";
+
+    // we concatenate all js in multiple attributes.
+    // because it's too much of a hassle to keep track
+    // otherwise.
+    for (; i < le; i++) {
+        text += script.jsAttributes[i].value + '\n';
+    }
+
+    return text;
+};
+
+/**
+ *
+ * check a single element with attributes
+ */
+DomChecker.prototype.checkSingleElementAttributes = function(
+        script, loadedScript, checker) {
+    "use strict";
+    var check, value, 
+        i = 0, 
+        le = script.jsAttributes.length,
+        text = "";
+
+    try {
+        check = checker.parseTree.freeTrivialCheck;
+        script.tree = checker;
+        script.result = check;		
+        script.status = statusTypes.CHECKED;
+    } catch (e) {
+        console.debug('problem checking inline scripts', e, e.lineNumber);
+        this.d.removeGivenJs(script);
+    }
+
+    this.processInlineCheckResult(script, check, checker);
+};
+
+DomChecker.prototype.processInlineCheckResult = function(
+        script, check, checker) {
+    "use strict";
+    console.debug("check.reason is", check.reason, "and type", check.type);
+    var hash = checker.hash;
+
+    if (this.d.inlineJsFree === true) {
+        console.debug('tagging', script.text, 'as accepted', "with reason", check.reason);
+        script.tagAsAccepted(this.d.pageURL, this.d.freeReason + " -- " + check.reason, hash);
+    }
+
+    // process the result.
+    if (check.type === checkTypes.FREE) {
+        // this is free.
+        console.debug('tagging', script.text, 'as accepted with reason', check.reason);
+        this.d.inlineJsFree = true;
+        this.d.freeReason = check.reason;
+        // add entry as accepted.
+        script.tagAsAccepted(this.d.pageURL, check.reason, hash);
+    } else if (check.type === checkTypes.FREE_SINGLE_ITEM) {
+        // accept this script.
+        console.debug("free single item, ", check.reason);
+        script.tagAsAccepted(this.d.pageURL, check.reason, hash);
+    } else if (check.type === checkTypes.NONTRIVIAL) {
+        console.debug("nontrivial hash is", hash);
+        if (this.d.inlineJsFree) {
+            // inline is free. So accept.
+            console.debug('tagging', script.text, 'as accepted');
+            script.tagAsAccepted(
+                    this.d.pageURL,
+                    this.d.freeReason + ' -- ' + check.reason,
+                    hash);
+        } else {
+            console.debug('tagging', script.text, 'as removed');
+            this.d.removeGivenJs(script, check.reason, false, hash);
+        }
+    } else if (!this.d.inlineJsFree &&
+        this.d.loadsHtmlExternalScripts &&
+        check.type === checkTypes.TRIVIAL_DEFINES_FUNCTION
+    ) {
+        // nontrivial, because defines function and loads
+        // external scripts
+        console.debug('tagging', script.text, 'as removed');
+        this.d.removeGivenJs(script, reasons.FUNCTIONS_INLINE, false, hash);
+    } else if (!this.d.loadsHtmlExternalScripts &&
+            check === checkTypes.TRIVIAL_DEFINES_FUNCTION
+    ) {
+        console.debug("Tag as accepted doesn't load another external script");
+        script.tagAsAccepted(this.d.pageURL, check.reason, hash);
+    } else if (check.type === checkTypes.TRIVIAL || 
+            check.type === checkTypes.TRIVIAL_DEFINES_FUNCTION ||
+            check.type === checkTypes.WHITELISTED
+    ) {
+        // add entry as accepted.
+        console.debug("Trivial accepted");
+        script.tagAsAccepted(this.d.pageURL, check.reason, hash);
+    } 
+
+    // next inline script, if applicable.
+    this.checkAllInlineScripts();
+};
+
+DomChecker.prototype.readyForExternal = function() {
+    "use strict";
+
+    console.debug('DomChecker.readyForExternal');
+    // done with those inline scripts, continue with
+    // the rest.
+    this.checkExternalScripts();
+};
+
+/**
+ * check a single inline script. 
+ */
+DomChecker.prototype.checkSingleInlineScript = function(
+        script, loadedScript, checker) {
+    "use strict";
+    var check, text;
+
+    console.debug('DomChecker.checkSingleInlineScript');
+
+    try {
+
+        check = checker.parseTree.freeTrivialCheck;
+
+        // update status.
+        script.tree = checker;
+        script.result = check;
+        console.debug("script result is", check.type);
+        script.status = statusTypes.CHECKED;
+
+    } catch (e) {
+        console.debug('problem checking inline scripts', e, e.lineNumber);
+        this.d.removeGivenJs(script, '', false, checker.hash);
+    }
+
+    this.processInlineCheckResult(script, check, checker);
+
+};
+
+/**
+ * checkExternalScripts
+ * Loop through series of external scripts,
+ * perform xhr to get their data, and check them
+ * to see whether they are free/nontrivial
+ *
+ */
+DomChecker.prototype.checkExternalScripts = function() {
+    "use strict";
+
+    console.debug('DomChecker.checkExternalScripts');
+
+    var i = 0;
+    var len = this.d.externalScripts.length;
+    var that = this;
+
+    console.debug("externalScripts length", len);
+    if (this.d.removedAllScripts || len === 0) {
+        // all js has already been removed.
+        // stop check.
+        this.wrapUpBeforeLeaving();
+        return;
+    }
+
+    for (; i < len; i++) {
+        this.xhr(
+            this.d.externalScripts[i],
+            function(script, scriptText) {
+                console.debug("In xhr callback for script url:", script.url);
+                if (scriptText === false) {
+                    that.d.removeGivenJs(script);
+                    that.d.scriptHasBeenTested();
+                    that.externalCheckIsDone();
+                    return;
+                }
+
+                console.debug('about to analyzeJS for script:', script.url);
+                that.analyzeJs(
+                    script,
+                    scriptText,
+                    that.checkSingleExternalScript.bind(that));
+            }
+        );
+    }
+};
+
+DomChecker.prototype.wrapUpBeforeLeaving = function() {
+    "use strict";
+
+    console.debug("wrap up before leaving triggered");
+    console.debug('wrapping up');
+    this.d.callback(this.d.dom);
+
+};
+
+DomChecker.prototype.analyzeJs = function(script, scriptText, callback) {
+    "use strict";
+    console.debug('DomChecker.analyzeJs for script:', script.url);
+    try {
+        var checker = jsChecker.jsChecker();
+        var url = "";
+        if (typeof script.url !== "undefined") {
+            url = script.url;
+        } else {
+            url = this.pageURL;
+        }
+        checker.searchJs(scriptText, function() {
+            console.debug("Analyze JS"/*, JSON.stringify(checker)*/);
+            timer.setTimeout(function() {
+                callback(script, scriptText, checker);
+            }, 0);
+        }, url);
+    } catch (x) {
+        console.debug('error', x, x.lineNumber, x.fileName);
+    }
+};
+
+/**
+ * Check a single external script.
+ */
+DomChecker.prototype.checkSingleExternalScript = function(
+    script, loadedScript, checker
+) {
+    "use strict";
+    var check;
+
+    console.debug('DomChecker.checkSingleExternalScript()');
+    try {
+        check = checker.parseTree.freeTrivialCheck;
+
+        script.tree = checker;
+        script.result = check;
+        console.debug('in checkSingleExternalScript, checker.hash is',
+                      checker.hash);
+        if (script.status != statusTypes.JSWEBLABEL) {
+            script.status = statusTypes.CHECKED;		
+        } 
+
+        if (check.type === checkTypes.FREE ||
+                check.type === checkTypes.FREE_SINGLE_ITEM
+        ) {
+            // add entry as accepted.
+            script.tagAsAccepted(this.d.pageURL, check.reason, checker.hash);
+        } 
+
+        else if (check.type === checkTypes.NONTRIVIAL) {
+            console.debug("Removing given js", check.reason);
+            this.d.removeGivenJs(script, check.reason, false, checker.hash);
+        }
+
+        else if (check.type === checkTypes.TRIVIAL ||
+                check.type === checkTypes.WHITELISTED
+        ) {
+            // if it's accepted, allow.
+            script.tagAsAccepted(this.d.pageURL, check.reason, checker.hash);
+        } else {
+            // anything else is nontrivial. Including TRIVIAL_DEFINES_FUNCTION.
+            console.debug("checker hash for remove is ", checker.hash);
+            this.d.removeGivenJs(
+                script, reasons.FUNCTIONS_EXTERNAL, false, checker.hash);
+        } 
+
+    } catch (e) {
+        console.debug('error in checkExternalScript',
+                      e, e.lineNumber, 'for script', script.url);
+
+        this.d.removeAllJs();
+        this.destroy();
+        return;
+    }
+    console.debug('script url is', script.url, 'result is', script.result);
+    this.d.scriptHasBeenTested();
+    this.externalCheckIsDone();
+};
+
+DomChecker.prototype.externalCheckIsDone = function() {
+    "use strict";
+    console.debug('DomChecker.externalCheckIsDone');
+
+    console.debug('scriptsTested is', this.d.scriptsTested);
+    console.debug('num external', this.d.numExternalScripts);
+
+    if (this.d.scriptsTested  >= this.d.numExternalScripts) {
+        console.debug('wrapping up external');
+        this.wrapUpBeforeLeaving();
+    } else {
+        var scriptsToCheck = this.d.numExternalScripts - this.d.scriptsTested;
+        console.debug('Not wrapping up! Waiting to check ' + scriptsToCheck +
+                      ' more script(s)');
+
+        if (this.d.externalScripts[0]) {
+            console.debug('script 0 is', this.d.externalScripts[0]);
+        }
+        if (this.d.externalScripts[1]) {
+            console.debug('script 1 is', this.d.externalScripts[1]);
+        }
+    }
+};
+
+/**
+ * xhr
+ * Perform a XMLHttpRequest on the url given.
+ * @param url string A URL.
+ * @return The response text.
+ */
+DomChecker.prototype.xhr = function(script, responseCallback) {
+    "use strict";
+
+    var regex = /^text\/html/i;	
+    var url = script.url;
+
+    try {
+        // add url to whitelist.
+        urlTester.addUrl(url);
+
+        // request module. Compatible with Https-Everywhere.
+        require('html_script_finder/dom_handler/request')
+            .request(script, responseCallback).request();
+    }  catch (x) {
+        console.debug('error', x, x.lineNumber, x.fileName);
+        responseCallback(script, false);
+    }
+};
+
+/**
+ * exports.domChecker
+ * Instantiate a brand new clone of the domChecker.
+ * @param dom obj The given dom for analysis.
+ * @param pageURL string the URL for the page.
+ * @param callback function callback when all the work has been performed.
+ */
+exports.domChecker = function(domHandler) {
+    "use strict";
+
+    var domChecker = new DomChecker();
+
+    domChecker.init(domHandler);
+
+    return domChecker;
+};
+
+exports.xhr = new DomChecker().xhr;