101 lines
		
	
	
		
			3.3 KiB
		
	
	
	
		
			JavaScript
		
	
	
	
	
	
			
		
		
	
	
			101 lines
		
	
	
		
			3.3 KiB
		
	
	
	
		
			JavaScript
		
	
	
	
	
	
| var config = require('./config')
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| var uuid = require('uuid')
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| 
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| var CspStrategy = {}
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| 
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| var defaultDirectives = {
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|   defaultSrc: ['\'self\''],
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|   scriptSrc: ['\'self\'', 'vimeo.com', 'https://gist.github.com', 'www.slideshare.net', 'https://query.yahooapis.com', '\'unsafe-eval\''],
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|   // ^ TODO: Remove unsafe-eval - webpack script-loader issues https://github.com/hackmdio/codimd/issues/594
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|   imgSrc: ['*'],
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|   styleSrc: ['\'self\'', '\'unsafe-inline\'', 'https://assets-cdn.github.com'], // unsafe-inline is required for some libs, plus used in views
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|   fontSrc: ['\'self\'', 'https://public.slidesharecdn.com'],
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|   objectSrc: ['*'], // Chrome PDF viewer treats PDFs as objects :/
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|   mediaSrc: ['*'],
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|   childSrc: ['*'],
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|   connectSrc: ['*']
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| }
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| 
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| var cdnDirectives = {
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|   scriptSrc: ['https://cdnjs.cloudflare.com', 'https://cdn.mathjax.org'],
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|   styleSrc: ['https://cdnjs.cloudflare.com', 'https://fonts.googleapis.com'],
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|   fontSrc: ['https://cdnjs.cloudflare.com', 'https://fonts.gstatic.com']
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| }
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| 
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| var disqusDirectives = {
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|   scriptSrc: ['https://*.disqus.com', 'https://*.disquscdn.com'],
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|   styleSrc: ['https://*.disquscdn.com'],
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|   fontSrc: ['https://*.disquscdn.com']
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| }
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| 
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| var googleAnalyticsDirectives = {
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|   scriptSrc: ['https://www.google-analytics.com']
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| }
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| 
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| CspStrategy.computeDirectives = function () {
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|   var directives = {}
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|   mergeDirectives(directives, config.csp.directives)
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|   mergeDirectivesIf(config.csp.addDefaults, directives, defaultDirectives)
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|   mergeDirectivesIf(config.useCDN, directives, cdnDirectives)
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|   mergeDirectivesIf(config.csp.addDisqus, directives, disqusDirectives)
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|   mergeDirectivesIf(config.csp.addGoogleAnalytics, directives, googleAnalyticsDirectives)
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|   if (!areAllInlineScriptsAllowed(directives)) {
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|     addInlineScriptExceptions(directives)
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|   }
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|   addUpgradeUnsafeRequestsOptionTo(directives)
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|   addReportURI(directives)
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|   return directives
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| }
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| 
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| function mergeDirectives (existingDirectives, newDirectives) {
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|   for (var propertyName in newDirectives) {
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|     var newDirective = newDirectives[propertyName]
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|     if (newDirective) {
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|       var existingDirective = existingDirectives[propertyName] || []
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|       existingDirectives[propertyName] = existingDirective.concat(newDirective)
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|     }
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|   }
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| }
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| 
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| function mergeDirectivesIf (condition, existingDirectives, newDirectives) {
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|   if (condition) {
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|     mergeDirectives(existingDirectives, newDirectives)
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|   }
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| }
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| 
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| function areAllInlineScriptsAllowed (directives) {
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|   return directives.scriptSrc.indexOf('\'unsafe-inline\'') !== -1
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| }
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| 
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| function addInlineScriptExceptions (directives) {
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|   directives.scriptSrc.push(getCspNonce)
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|   // TODO: This is the SHA-256 hash of the inline script in build/reveal.js/plugins/notes/notes.html
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|   // Any more clean solution appreciated.
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|   directives.scriptSrc.push('\'sha256-L0TsyAQLAc0koby5DCbFAwFfRs9ZxesA+4xg0QDSrdI=\'')
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| }
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| 
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| function getCspNonce (req, res) {
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|   return "'nonce-" + res.locals.nonce + "'"
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| }
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| 
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| function addUpgradeUnsafeRequestsOptionTo (directives) {
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|   if (config.csp.upgradeInsecureRequests === 'auto' && config.useSSL) {
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|     directives.upgradeInsecureRequests = true
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|   } else if (config.csp.upgradeInsecureRequests === true) {
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|     directives.upgradeInsecureRequests = true
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|   }
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| }
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| 
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| function addReportURI (directives) {
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|   if (config.csp.reportURI) {
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|     directives.reportUri = config.csp.reportURI
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|   }
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| }
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| 
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| CspStrategy.addNonceToLocals = function (req, res, next) {
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|   res.locals.nonce = uuid.v4()
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|   next()
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| }
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| 
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| module.exports = CspStrategy
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