diff options
Diffstat (limited to 'main_background.js')
| -rw-r--r-- | main_background.js | 382 |
1 files changed, 15 insertions, 367 deletions
diff --git a/main_background.js b/main_background.js index 48607c2..fd11753 100644 --- a/main_background.js +++ b/main_background.js @@ -3,6 +3,7 @@ * * * Copyright (C) 2017, 2018 Nathan Nichols * Copyright (C) 2018 Ruben Rodriguez <ruben@gnu.org> +* Copyright (C) 2022 Yuchen Pei <id@ypei.org> * * This file is part of GNU LibreJS. * @@ -20,68 +21,15 @@ * along with GNU LibreJS. If not, see <http://www.gnu.org/licenses/>. */ -const acorn = require('acorn'); -const licenseLib = require('./common/checks.js'); +const checkLib = require('./common/checks.js'); const { ResponseProcessor } = require('./bg/ResponseProcessor'); const { Storage, ListStore, hash } = require('./common/Storage'); const { ListManager } = require('./bg/ListManager'); const { ExternalLicenses } = require('./bg/ExternalLicenses'); -const { licenses } = require('./common/license_definitions'); -const { patternUtils } = require('./common/pattern_utils'); +const { makeDebugLogger } = require('./common/debug.js'); -console.log('main_background.js'); -/** -* If this is true, it evaluates entire scripts instead of returning as soon as it encounters a violation. -* -* Also, it controls whether or not this part of the code logs to the console. -* -*/ -var DEBUG = false; // debug the JS evaluation -var PRINT_DEBUG = false; // Everything else -var time = Date.now(); - -function dbg_print(a, b) { - if (PRINT_DEBUG == true) { - console.log('Time spent so far: ' + (Date.now() - time) / 1000 + ' seconds'); - if (b === undefined) { - console.log(a); - } else { - console.log(a, b); - } - } -} - -/* - NONTRIVIAL THINGS: - - Fetch - - XMLhttpRequest - - eval() - - ? - JAVASCRIPT CAN BE FOUND IN: - - Event handlers (onclick, onload, onsubmit, etc.) - - <script>JS</script> - - <script src="/JS.js"></script> - WAYS TO DETERMINE PASS/FAIL: - - "// @license [magnet link] [identifier]" then "// @license-end" (may also use /* comments) - - Automatic whitelist: (http://bzr.savannah.gnu.org/lh/librejs/dev/annotate/head:/data/script_libraries/script-libraries.json_ -*/ - -// These are objects that it will search for in an initial regex pass over non-free scripts. -const RESERVED_OBJECTS = [ - //"document", - //"window", - 'fetch', - 'XMLHttpRequest', - 'chrome', // only on chrome - 'browser', // only on firefox - 'eval' -]; -const LOOPKEYS = new Set(['for', 'if', 'while', 'switch']); -const OPERATORS = new Set(['||', '&&', '=', '==', '++', '--', '+=', '-=', '*']); -// @license match, second and third capture groups are canonicalUrl -// and license name -const OPENING_LICENSE_RE = /\/[/*]\s*?(@license)\s+(\S+)\s+(\S+).*$/mi; -const CLOSING_LICENSE_RE = /\/([*/])\s*@license-end\s*(\*\/)?/mi; +const PRINT_DEBUG = false; +const dbg_print = makeDebugLogger('main_background.js', PRINT_DEBUG, Date.now()); /* * @@ -415,294 +363,6 @@ async function onTabActivated({ tabId }) { } /* *********************************************************************************************** */ - -const fnameData = require('./fname_data.json').fname_data; - -//************************this part can be tested in the HTML file index.html's script test.js**************************** - -/** - * Checks whether script is trivial by analysing its tokens. - * - * Returns an array of - * [flag (boolean, true if trivial), reason (string, human readable report)]. - */ -function fullEvaluate(script) { - if (script === undefined || script == '') { - return [true, 'Harmless null script']; - } - - let tokens; - - try { - tokens = acorn.tokenizer(script); - } catch (e) { - console.warn('Tokenizer could not be initiated (probably invalid code)'); - return [false, 'Tokenizer could not be initiated (probably invalid code)']; - } - try { - var toke = tokens.getToken(); - } catch (e) { - console.log(script); - console.log(e); - console.warn('couldn\'t get first token (probably invalid code)'); - console.warn('Continuing evaluation'); - } - - let amtloops = 0; - let definesFunctions = false; - - /** - * Given the end of an identifer token, it tests for parentheses - */ - function is_bsn(end) { - let i = 0; - while (script.charAt(end + i).match(/\s/g) !== null) { - i++; - if (i >= script.length - 1) { - return false; - } - } - return script.charAt(end + i) == '['; - } - - function evaluateByTokenValue(toke) { - const value = toke.value; - if (OPERATORS.has(value)) { - // It's just an operator. Javascript doesn't have operator overloading so it must be some - // kind of primitive (I.e. a number) - } else { - const status = fnameData[value]; - if (status === true) { // is the identifier banned? - dbg_print('%c NONTRIVIAL: nontrivial token: \'' + value + '\'', 'color:red'); - if (DEBUG == false) { - return [false, 'NONTRIVIAL: nontrivial token: \'' + value + '\'']; - } - } else if (status === false || status === undefined) {// is the identifier not banned or user defined? - // Is there bracket suffix notation? - if (is_bsn(toke.end)) { - dbg_print('%c NONTRIVIAL: Bracket suffix notation on variable \'' + value + '\'', 'color:red'); - if (DEBUG == false) { - return [false, '%c NONTRIVIAL: Bracket suffix notation on variable \'' + value + '\'']; - } - } - } else { - dbg_print('trivial token:' + value); - } - } - return [true, '']; - } - - function evaluateByTokenTypeKeyword(keyword) { - if (toke.type.keyword == 'function') { - dbg_print('%c NOTICE: Function declaration.', 'color:green'); - definesFunctions = true; - } - - if (LOOPKEYS.has(keyword)) { - amtloops++; - if (amtloops > 3) { - dbg_print('%c NONTRIVIAL: Too many loops/conditionals.', 'color:red'); - if (DEBUG == false) { - return [false, 'NONTRIVIAL: Too many loops/conditionals.']; - } - } - } - return [true, '']; - } - - while (toke !== undefined && toke.type != acorn.tokTypes.eof) { - if (toke.type.keyword !== undefined) { - //dbg_print("Keyword:"); - //dbg_print(toke); - - // This type of loop detection ignores functional loop alternatives and ternary operators - const tokeTypeRes = evaluateByTokenTypeKeyword(toke.type.keyword); - if (tokeTypeRes[0] === false) { - return tokeTypeRes; - } - } else if (toke.value !== undefined) { - const tokeValRes = evaluateByTokenValue(toke); - if (tokeValRes[0] === false) { - return tokeValRes; - } - } - // If not a keyword or an identifier it's some kind of operator, field parenthesis, brackets - try { - toke = tokens.getToken(); - } catch (e) { - dbg_print('Denied script because it cannot be parsed.'); - return [false, 'NONTRIVIAL: Cannot be parsed. This could mean it is a 404 error.']; - } - } - - dbg_print('%cAppears to be trivial.', 'color:green;'); - if (definesFunctions === true) - return [true, 'Script appears to be trivial but defines functions.']; - else - return [true, 'Script appears to be trivial.']; -} - - -//**************************************************************************************************** -/** -* This is the entry point for full code evaluation for triviality. -* -* Performs the initial pass on code to see if it needs to be completely parsed -* -* This can only determine if a script is bad, not if it's good -* -* If it passes the intitial pass, it runs the full pass and returns the result - -* It returns an array of [flag (boolean, false if "bad"), reason (string, human readable report)] -* -*/ -function evaluate(script, name) { - const reservedResult = evaluateForReservedObj(script, name); - if (reservedResult[0] === true) { - dbg_print('%c pass', 'color:green;'); - } else { - return reservedResult; - } - - return fullEvaluate(script); -} - -function evaluateForReservedObj(script, name) { - function reservedObjectRegex(object) { - const arithOperators = '\\+\\-\\*\\/\\%\\='; - return new RegExp('(?:[^\\w\\d]|^|(?:' + arithOperators + '))' + object + '(?:\\s*?(?:[\\;\\,\\.\\(\\[])\\s*?)', 'g'); - } - const mlComment = /\/\*([\s\S]+?)\*\//g; - const ilComment = /\/\/.+/gm; - const temp = script.replace(/'.+?'+/gm, '\'string\'').replace(/".+?"+/gm, '"string"').replace(mlComment, '').replace(ilComment, ''); - dbg_print('%c ------evaluation results for ' + name + '------', 'color:white'); - dbg_print('Script accesses reserved objects?'); - - // This is where individual "passes" are made over the code - for (const reserved of RESERVED_OBJECTS) { - if (reservedObjectRegex(reserved).exec(temp) != null) { - dbg_print('%c fail', 'color:red;'); - return [false, 'Script uses a reserved object (' + reserved + ')']; - } - } - return [true, 'Reserved object not found.']; -} - -// checks license in an OPENING_LICENSE_RE match -function checkLicenseInMatch(match) { - if (!(Array.isArray(match) && match.length >= 4)) { - return [false, 'Malformed or unrecognized license tag.']; - } - - const [all, first] = [match[0], match[2].replace('&', '&')]; - - for (const key in licenses) { - // Match by canonicalUrl - for (const url of licenses[key].canonicalUrl) { - if (first === url || first === url.replace('^http://', 'https://')) { - return [true, `Recognized license: "${licenses[key].licenseName}".`]; - } - } - } - return [false, `Unrecognized license tag: "${all}"`]; -} - - -/** - * - * Evaluates the content of a script for licenses and triviality - * scriptSrc: content of the script; name: script name; external: - * whether the script is external - * - * Returns - * [ - * true (accepted) or false (denied), - * edited content, - * reason text - * ] - */ -function licenseRead(scriptSrc, name, external = false) { - let inSrc = scriptSrc.trim(); - if (!inSrc) return [true, scriptSrc, 'Empty source.']; - - // Check for @licstart .. @licend method - const license = licenseLib.check(scriptSrc); - if (license) { - return [true, scriptSrc, `Licensed under: ${license}`]; - } - - let outSrc = ''; - let reason = ''; - let partsDenied = false; - let partsAccepted = false; - - function checkTriviality(s) { - if (!patternUtils.removeJsComments(s).trim()) { - return true; // empty, ignore it - } - const [trivial, message] = external ? - [false, 'External script with no known license'] - : evaluate(s, name); - if (trivial) { - partsAccepted = true; - outSrc += s; - } else { - partsDenied = true; - if (s.startsWith('javascript:')) - outSrc += `# LIBREJS BLOCKED: ${message}`; - else - outSrc += `/*\nLIBREJS BLOCKED: ${message}\n*/`; - } - reason += `\n${message}`; - } - - // Consume inSrc by checking licenses in all @license / @license-end - // blocks and triviality outside these blocks - while (inSrc) { - const openingMatch = OPENING_LICENSE_RE.exec(inSrc); - const openingIndex = openingMatch ? openingMatch.index : inSrc.length; - // checks the triviality of the code before the license tag, if any - checkTriviality(inSrc.substring(0, openingIndex)); - inSrc = inSrc.substring(openingIndex); - if (!inSrc) break; - - // checks the remaining part, that starts with an @license - const closureMatch = CLOSING_LICENSE_RE.exec(inSrc); - if (!closureMatch) { - const msg = 'ERROR: @license with no @license-end'; - return [false, `\n/*\n ${msg} \n*/\n`, msg]; - } - let closureEndIndex = closureMatch.index + closureMatch[0].length; - const commentEndOffset = inSrc.substring(closureEndIndex).indexOf(closureMatch[1] === '*' ? '*/' : '\n'); - if (commentEndOffset !== -1) { - closureEndIndex += commentEndOffset; - } - - const [licenseOK, message] = checkLicenseInMatch(openingMatch); - if (licenseOK) { - outSrc += inSrc.substr(0, closureEndIndex); - partsAccepted = true; - } else { - outSrc += `\n/*\n${message}\n*/\n`; - partsDenied = true; - } - reason += `\n${message}`; - - // trim off everything we just evaluated - inSrc = inSrc.substring(closureEndIndex).trim(); - } - - if (partsDenied) { - if (partsAccepted) { - reason = `Some parts of the script have been disabled (check the source for details).\n^--- ${reason}`; - } - return [false, outSrc, reason]; - } - - return [true, scriptSrc, reason]; -} - -/* *********************************************************************************************** */ // TODO: Test if this script is being loaded from another domain compared to activityReports[tabid]["url"] /** @@ -732,7 +392,7 @@ async function checkScriptAndUpdateReport(scriptSrc, url, tabId, whitelisted, re return result(`/* LibreJS: script whitelisted by user preference. */\n${scriptSrc}`); } - const [accepted, editedSource, reason] = listManager.builtInHashes.has(hash(scriptSrc)) ? [true, scriptSrc, 'Common script known to be free software.'] : licenseRead(scriptSrc, scriptName, isExternal); + const [accepted, editedSource, reason] = listManager.builtInHashes.has(hash(scriptSrc)) ? [true, scriptSrc, 'Common script known to be free software.'] : checkLib.checkScriptSource(scriptSrc, scriptName, isExternal); if (tabId < 0) { return result(editedSource); @@ -995,19 +655,10 @@ function read_metadata(meta_element) { return false; } - // this should be adequete to escape the HTML escaping - parts[0] = parts[0].replace(/&/g, '&'); - - try { - for (const url of licenses[parts[1]].canonicalUrl) { - if (url.startsWith('magnet:') && url == parts[0]) { - return true; - } - } - console.log('invalid (doesn\'t match licenses)'); - return false; - } catch (error) { - console.log('invalid (threw error, key didn\'t exist)'); + if (checkLib.checkMagnet(parts[0])) { + return true; + } else { + console.log('invalid (doesn\'t match licenses or key didn\'t exist)'); return false; } } @@ -1044,24 +695,21 @@ async function editHtml(html, documentUrl, tabId, frameId, whitelisted) { } } - let license = null; - if (first_script_src != '') { - license = licenseLib.check(first_script_src); - } + const licenseName = checkLib.checkLicenseText(first_script_src); let findLine = finder => finder.test(html) && html.substring(0, finder.lastIndex).split(/\n/).length || 0; - if (read_metadata(meta_element) || license) { + if (read_metadata(meta_element) || licenseName) { console.log('Valid license for intrinsic events found'); let line, extras; if (meta_element) { line = findLine(/id\s*=\s*['"]?LibreJS-info\b/gi); extras = '(0)'; - } else if (license) { + } else if (licenseName) { line = html.substring(0, html.indexOf(first_script_src)).split(/\n/).length; extras = '\n' + first_script_src; } let viewUrl = line ? `view-source:${documentUrl}#line${line}(<${meta_element ? meta_element.tagName : 'SCRIPT'}>)${extras}` : url; - addReportEntry(tabId, { url, 'accepted': [viewUrl, `Global license for the page: ${license}`] }); + addReportEntry(tabId, { url, 'accepted': [viewUrl, `Global license for the page: ${licenseName}`] }); // Do not process inline scripts scripts = []; } else { @@ -1219,7 +867,7 @@ async function init_addon() { // Analyzes all the html documents and external scripts as they're loaded ResponseProcessor.install(ResponseHandler); - licenseLib.init(); + checkLib.init(); const Test = require('./common/Test'); if (Test.getURL()) { |