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Diffstat (limited to 'lib/js_checker/relation_checker.js')
| -rw-r--r-- | lib/js_checker/relation_checker.js | 289 |
1 files changed, 289 insertions, 0 deletions
diff --git a/lib/js_checker/relation_checker.js b/lib/js_checker/relation_checker.js new file mode 100644 index 0000000..1904812 --- /dev/null +++ b/lib/js_checker/relation_checker.js @@ -0,0 +1,289 @@ +/** + * 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/>. + * + */ +/** + * relation_checker.js + * + * Finds out if two scripts are related to each other. + * + */ +const types = require("js_checker/constant_types"); + +const token = types.token; + +// all predefined window properties (methods and variables). +const windowPropertiesHash = { + "addEventListener": 1, "alert": 1, "applicationCache": 1, + "Array": 1, "ArrayBuffer": 1, "atob": 1, "back": 1, "blur": 1, + "Boolean": 1, "btoa": 1, "captureEvents": 1, "CharacterData": 1, + "clearInterval": 1, "clearTimeout": 1, "close": 1, "closed": 1, + "Components": 1, "confirm": 1, "console": 1, "constructor": 1, + "content": 1, "controllers": 1, "crypto": 1, + "CSSStyleDeclaration": 1, "Date": 1, "decodeURI": 1, + "decodeURIComponent": 1, "defaultStatus": 1, + "disableExternalCapture": 1, "dispatchEvent": 1, "Document": 1, + "document": 1, "DocumentType": 1, "dump": 1, "Element": 1, + "enableExternalCapture": 1, "encodeURI": 1, "encodeURIComponent": 1, + "Error": 1, "escape": 1, "eval": 1, "EvalError": 1, "Event": 1, + "find": 1, "Float32Array": 1, "Float64Array": 1, "focus": 1, + "forward": 1, "frameElement": 1, "frames": 1, "fullScreen": 1, + "Function": 1, "Generator": 1, "getComputedStyle": 1, + "getInterface": 1, "getSelection": 1, "globalStorage": 1, + "history": 1, "home": 1, "HTMLBodyElement": 1, "HTMLCollection": 1, + "HTMLDivElement": 1, "HTMLDocument": 1, "HTMLElement": 1, + "HTMLHeadElement": 1, "HTMLHeadingElement": 1, "HTMLHtmlElement": 1, + "HTMLStyleElement": 1, "HTMLUnknownElement": 1, "Infinity": 1, + "innerHeight": 1, "innerWidth": 1, "InstallTrigger": 1, + "Int16Array": 1, "Int32Array": 1, "Int8Array": 1, "InternalError": 1, + "isFinite": 1, "isNaN": 1, "isXMLName": 1, "Iterator": 1, + "JSON": 1, "length": 1, "localStorage": 1, "Location": 1, + "location": 1, "locationbar": 1, "matchMedia": 1, "Math": 1, + "menubar": 1, "moveBy": 1, "moveTo": 1, "mozAnimationStartTime": 1, + "mozIndexedDB": 1, "mozInnerScreenX": 1, "mozInnerScreenY": 1, + "mozPaintCount": 1, "mozRequestAnimationFrame": 1, "name": 1, + "Namespace": 1, "NaN": 1, "navigator": 1, "netscape": 1, + "Node": 1, "NodeList": 1, "Number": 1, "Object": 1, "open": 1, + "openDialog": 1, "opener": 1, "outerHeight": 1, "outerWidth": 1, + "pageXOffset": 1, "pageYOffset": 1, "parent": 1, "parseFloat": 1, + "parseInt": 1, "performance": 1, "personalbar": 1, "pkcs11": 1, + "postMessage": 1, "print": 1, "prompt": 1, "QName": 1, + "RangeError": 1, "ReferenceError": 1, "RegExp": 1, + "releaseEvents": 1, "removeEventListener": 1, "resizeBy": 1, + "resizeTo": 1, "routeEvent": 1, "screen": 1, "screenX": 1, + "screenY": 1, "scroll": 1, "scrollbars": 1, "scrollBy": 1, + "scrollByLines": 1, "scrollByPages": 1, "scrollMaxX": 1, + "scrollMaxY": 1, "scrollTo": 1, "scrollX": 1, "scrollY": 1, + "self": 1, "sessionStorage": 1, "setInterval": 1, "setResizable": 1, + "setTimeout": 1, "showModalDialog": 1, "sizeToContent": 1, + "status": 1, "statusbar": 1, "stop": 1, "StopIteration": 1, + "StorageList": 1, "String": 1, "SyntaxError": 1, "Text": 1, + "toolbar": 1, "top": 1, "TypeError": 1, "Uint16Array": 1, + "Uint32Array": 1, "Uint8Array": 1, "Uint8ClampedArray": 1, + "undefined": 1, "unescape": 1, "uneval": 1, "updateCommands": 1, + "URIError": 1, "URL": 1, "WeakMap": 1, "Window": 1, "window": 1, + "XML": 1, "XMLList": 1, "XPCNativeWrapper": 1}; + +// all predefined document properties. +const documentPropertiesHash = {'activeElement': 1, 'addBinding': 1, + 'addEventListener': 1, 'adoptNode': 1, 'alinkColor': 1, 'anchors': 1, + 'appendChild': 1, 'applets': 1, 'ATTRIBUTE_NODE': 1, 'attributes': 1, + 'baseURI': 1, 'bgColor': 1, 'body': 1, 'captureEvents': 1, + 'CDATA_SECTION_NODE': 1, 'characterSet': 1, 'childNodes': 1, 'clear': + 1, 'cloneNode': 1, 'close': 1, 'COMMENT_NODE': 1, + 'compareDocumentPosition': 1, 'compatMode': 1, 'contentType': 1, + 'cookie': 1, 'createAttribute': 1, 'createAttributeNS': 1, + 'createCDATASection': 1, 'createComment': 1, 'createDocumentFragment': + 1, 'createElement': 1, 'createElementNS': 1, 'createEvent': 1, + 'createExpression': 1, 'createNodeIterator': 1, 'createNSResolver': 1, + 'createProcessingInstruction': 1, 'createRange': 1, 'createTextNode': + 1, 'createTreeWalker': 1, 'currentScript': 1, 'defaultView': 1, + 'designMode': 1, 'dir': 1, 'dispatchEvent': 1, 'doctype': 1, + 'DOCUMENT_FRAGMENT_NODE': 1, 'DOCUMENT_NODE': 1, + 'DOCUMENT_POSITION_CONTAINED_BY': 1, 'DOCUMENT_POSITION_CONTAINS': 1, + 'DOCUMENT_POSITION_DISCONNECTED': 1, 'DOCUMENT_POSITION_FOLLOWING': 1, + 'DOCUMENT_POSITION_IMPLEMENTATION_SPECIFIC': 1, + 'DOCUMENT_POSITION_PRECEDING': 1, 'DOCUMENT_TYPE_NODE': 1, + 'documentElement': 1, 'documentURI': 1, 'domain': 1, 'ELEMENT_NODE': + 1, 'elementFromPoint': 1, 'embeds': 1, 'enableStyleSheetsForSet': 1, + 'ENTITY_NODE': 1, 'ENTITY_REFERENCE_NODE': 1, 'evaluate': 1, + 'execCommand': 1, 'execCommandShowHelp': 1, 'fgColor': 1, + 'firstChild': 1, 'forms': 1, 'getAnonymousElementByAttribute': 1, + 'getAnonymousNodes': 1, 'getBindingParent': 1, 'getElementById': 1, + 'getElementsByClassName': 1, 'getElementsByName': 1, + 'getElementsByTagName': 1, 'getElementsByTagNameNS': 1, + 'getSelection': 1, 'getUserData': 1, 'hasAttributes': 1, + 'hasChildNodes': 1, 'hasFocus': 1, 'head': 1, 'images': 1, + 'implementation': 1, 'importNode': 1, 'inputEncoding': 1, + 'insertBefore': 1, 'isDefaultNamespace': 1, 'isEqualNode': 1, + 'isSameNode': 1, 'isSupported': 1, 'lastChild': 1, 'lastModified': 1, + 'lastStyleSheetSet': 1, 'linkColor': 1, 'links': 1, + 'loadBindingDocument': 1, 'localName': 1, 'location': 1, + 'lookupNamespaceURI': 1, 'lookupPrefix': 1, 'mozSetImageElement': 1, + 'mozSyntheticDocument': 1, 'namespaceURI': 1, 'nextSibling': 1, + 'nodeName': 1, 'nodeType': 1, 'nodeValue': 1, 'normalize': 1, + 'NOTATION_NODE': 1, 'open': 1, 'ownerDocument': 1, 'parentNode': 1, + 'plugins': 1, 'preferredStyleSheetSet': 1, 'prefix': 1, + 'previousSibling': 1, 'PROCESSING_INSTRUCTION_NODE': 1, + 'queryCommandEnabled': 1, 'queryCommandIndeterm': 1, + 'queryCommandState': 1, 'queryCommandSupported': 1, + 'queryCommandText': 1, 'queryCommandValue': 1, 'querySelector': 1, + 'querySelectorAll': 1, 'readyState': 1, 'referrer': 1, + 'releaseCapture': 1, 'releaseEvents': 1, 'removeBinding': 1, + 'removeChild': 1, 'removeEventListener': 1, 'replaceChild': 1, + 'routeEvent': 1, 'selectedStyleSheetSet': 1, 'setUserData': 1, + 'styleSheets': 1, 'styleSheetSets': 1, 'TEXT_NODE': 1, 'textContent': + 1, 'title': 1, 'URL': 1, 'vlinkColor': 1, 'write': 1, 'writeln': 1, + 'xmlEncoding': 1, 'xmlStandalone': 1, 'xmlVersion': 1}; + +var relationChecker = { + + // identifies scripts across modules. + scriptId: null, + + // stores all left-side identifier in 'assign' types. + assignments: null, + + // stores var declarations in global scope. + variableDeclarations: null, + + // stores top declarations in global scope. + functionDeclarations: null, + + nonWindowProperties: null, + + init: function (scriptId) { + this.scriptId = scriptId; + this.assignments = []; + this.variableDeclarations = {}; + this.functionDeclarations = {}; + this.nonWindowProperties = {}; + }, + + isWindowProperty: function (identifier) { + return (identifier in windowPropertiesHash) ? true : false; + }, + + isDocumentProperty: function (identifier) { + return (identifier in documentPropertiesHash) ? true : false; + }, + + storeNodeVars: function (n) { + if (n.varDecls != undefined) { + var i = 0, le = n.varDecls.length; + for (; i < le; i++) { + this.variableDeclarations[n.varDecls[i].value] = 1; + } + } + }, + + storeNodeFunctions: function (n) { + if (n.funDecls != undefined) { + var i = 0, le = n.funDecls.length; + for (; i < le; i++) { + this.functionDeclarations[n.funDecls[i].name] = 1; + } + } + }, + storeGlobalDeclarations: function (topNode) { + this.storeNodeVars(topNode); + this.storeNodeFunctions(topNode); + }, + storeNodeGlobalDeclarations: function (n) { + if (n.global === true) { + this.storeNodeVars(n); + this.storeNodeFunctions(n); + } + }, + + storeNodeAssignments: function (n) { + if (n.type === token.ASSIGN && + n.children != undefined && + n.children[0].type === token.IDENTIFIER) { + this.assignments.push(n.children[0].value); + } + }, + + // checks the parent script is in global scope. + isInGlobalScope: function (n) { + var currentNode = n; + + while (currentNode != undefined) { + if (currentNode.type === token.SCRIPT && + currentNode.global === true) { + return true; + } else if (currentNode.type === token.SCRIPT) { + return false; + } + currentNode = currentNode.parent; + } + }, + + // looks for an identifier being declared as either a + // variable or a function within the scope. Currently, + // we don't care about assignments. + lookForIdentifierInAllScopes: function (n, val) { + + var currentNode = n, i, le, vars, funcs; + while (currentNode != undefined) { + if (currentNode.varDecls != undefined) { + vars = currentNode.varDecls; + le = vars.length; + for (i = 0; i < le; i++) { + if (vars[i].value === val) { + console.debug('FOUND declaration for', val); + return true; + } + } + } + if (currentNode.funDecls != undefined) { + funcs = currentNode.funDecls; + le = funcs.length; + for (i = 0; i < le; i++) { + if (funcs[i].name === val) { + console.debug('FOUND function declaration for', val); + return true; + } + } + } + currentNode = currentNode.parent; + } + console.debug('did not find declaration or assignment for', val); + }, + + // Heuristic method for window properties. + // this doesn't prove they are window properties, but + // it allows to make a good guess. These variables could have + // been assigned to something else... + checkIdentifierIsWindowProperty: function (n) { + + if (n.type === token.IDENTIFIER && + (n.parent.type === token.CALL || + (n.parent.type === token.DOT && + n.previous != undefined && + (n.previous.type === token.THIS || + (n.previous.type === token.IDENTIFIER && + n.previous.value === 'window')))) && + n.value in windowPropertiesHash) { + + this.lookForIdentifierInAllScopes(n, n.value); + + } + + else if (n.type === token.IDENTIFIER && + n.parent != undefined && + n.parent.type === token.DOT && + n.previous != undefined && + n.previous.type === token.THIS && + this.isInGlobalScope(n)) { + console.debug(n.type, 'use of this in the global scope, seems ok.', n.value); + } + else if (n.type === token.IDENTIFIER) { + // not found. + console.debug(n.type, 'probably not a window prop', n.value); + this.nonWindowProperties[n.value] = 1; + } + } + +}; + +exports.relationChecker = function (scriptId) { + var obj = Object.create(relationChecker); + obj.init(scriptId); + return obj; +}; |