56 lines
3.4 KiB
JavaScript
56 lines
3.4 KiB
JavaScript
'use strict';
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// This capability stays in the main process. Neither pages nor agents receive CDP access.
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const owners=new WeakMap();
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function protectClipboardPrimitives(){
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const prototype=Document.prototype,existing=Object.getOwnPropertyDescriptor(prototype,'execCommand');
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if(existing?.value?._managedClipboardGuard===true&&!existing.configurable)return;
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const original=prototype.execCommand,apply=Reflect.apply,test=RegExp.prototype.test.bind(/^(copy|cut|paste)/i);
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function managedClipboardCommand(command,...args){
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if(typeof command!=='string'||test(command))return false;
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return apply(original,this,[command,...args]);
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}
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Object.defineProperty(managedClipboardCommand,'_managedClipboardGuard',{value:true});
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Object.defineProperty(prototype,'execCommand',{value:managedClipboardCommand,writable:false,configurable:false});
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const SecurityException=DOMException;
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const denyReplacement=()=>{throw new SecurityException('Managed document replacement is disabled','SecurityError');};
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for(const name of ['open','write','writeln'])Object.defineProperty(prototype,name,{value:denyReplacement,writable:false,configurable:false});
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const deny=event=>{event.preventDefault();event.stopImmediatePropagation();};
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for(const name of ['copy','cut','paste','dragstart','dragover','drop'])window.addEventListener(name,deny,true);
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const transferred=RegExp.prototype.test.bind(/^(insertFromPaste|insertFromDrop|deleteByCut)/);
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window.addEventListener('beforeinput',event=>{if(transferred(event.inputType||''))deny(event);},true);
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}
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const source=`(${protectClipboardPrimitives.toString()})();`;
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function deadline(operation){let timer;return Promise.race([operation,new Promise((_,reject)=>{timer=setTimeout(()=>reject(Error('Page security initialization timed out')),5000);})]).finally(()=>clearTimeout(timer));}
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async function attachPageClipboardGuard(contents,onFailure){
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const api=contents.debugger;
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if(!api||api.isAttached()||owners.has(contents))throw Error('Page security initialization unavailable');
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const owner={api,healthy:false};
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const detached=()=>{owners.delete(contents);owner.healthy=false;if(!contents.isDestroyed())onFailure();};
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owner.detached=detached;
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api.on('detach',detached);
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try{
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api.attach('1.3');
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await deadline(api.sendCommand('Page.enable',{}));
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const registration=await deadline(api.sendCommand('Page.addScriptToEvaluateOnNewDocument',{source}));
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if(typeof registration?.identifier!=='string'||!registration.identifier||!api.isAttached())throw Error('Page security initialization failed');
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owner.healthy=true;owners.set(contents,owner);
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}catch{
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api.removeListener('detach',detached);
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if(api.isAttached())api.detach();
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throw Error('Page security initialization failed');
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}
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}
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function guardedScreenshot(contents,parameters){
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const owner=owners.get(contents);
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if(!owner)return null;
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if(!owner.healthy||owner.api!==contents.debugger||!owner.api.isAttached())throw Error('Page security connection unavailable');
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// Only the fixed screenshot command is shared. There is no general command dispatcher.
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return owner.api.sendCommand('Page.captureScreenshot',parameters);
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}
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function disposePageClipboardGuard(contents){
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const owner=owners.get(contents);if(!owner)return;
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owners.delete(contents);owner.healthy=false;owner.api.removeListener('detach',owner.detached);
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if(owner.api.isAttached())owner.api.detach();
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}
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module.exports={attachPageClipboardGuard,guardedScreenshot,disposePageClipboardGuard};
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