javascript-obfuscator
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JavaScript obfuscator
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text/typescript
import { inject, injectable, } from 'inversify';
import { ServiceIdentifiers } from '../../container/ServiceIdentifiers';
import * as estraverse from 'estraverse';
import * as ESTree from 'estree';
import { TControlFlowCustomNodeFactory } from '../../types/container/custom-nodes/TControlFlowCustomNodeFactory';
import { TInitialData } from '../../types/TInitialData';
import { TStatement } from '../../types/node/TStatement';
import { IArrayUtils } from '../../interfaces/utils/IArrayUtils';
import { ICustomNode } from '../../interfaces/custom-nodes/ICustomNode';
import { IOptions } from '../../interfaces/options/IOptions';
import { IRandomGenerator } from '../../interfaces/utils/IRandomGenerator';
import { IVisitor } from '../../interfaces/node-transformers/IVisitor';
import { ControlFlowCustomNode } from '../../enums/custom-nodes/ControlFlowCustomNode';
import { TransformationStage } from '../../enums/node-transformers/TransformationStage';
import { AbstractNodeTransformer } from '../AbstractNodeTransformer';
import { BlockStatementControlFlowFlatteningNode } from '../../custom-nodes/control-flow-flattening-nodes/BlockStatementControlFlowFlatteningNode';
import { NodeGuards } from '../../node/NodeGuards';
import { NodeUtils } from '../../node/NodeUtils';
()
export class BlockStatementControlFlowTransformer extends AbstractNodeTransformer {
/**
* @type {IArrayUtils}
*/
private readonly arrayUtils: IArrayUtils;
/**
* @type {TControlFlowCustomNodeFactory}
*/
private readonly controlFlowCustomNodeFactory: TControlFlowCustomNodeFactory;
/**
* @param {TControlFlowCustomNodeFactory} controlFlowCustomNodeFactory
* @param {IArrayUtils} arrayUtils
* @param {IRandomGenerator} randomGenerator
* @param {IOptions} options
*/
public constructor (
controlFlowCustomNodeFactory: TControlFlowCustomNodeFactory,
(ServiceIdentifiers.IArrayUtils) arrayUtils: IArrayUtils,
(ServiceIdentifiers.IRandomGenerator) randomGenerator: IRandomGenerator,
(ServiceIdentifiers.IOptions) options: IOptions
) {
(ServiceIdentifiers.Factory__IControlFlowCustomNode)
super(randomGenerator, options);
this.controlFlowCustomNodeFactory = controlFlowCustomNodeFactory;
this.arrayUtils = arrayUtils;
}
/**
* @param {Node} node
* @returns {boolean}
*/
private static isProhibitedStatementNode (node: ESTree.Node): boolean {
const isBreakOrContinueStatement: boolean = NodeGuards.isBreakStatementNode(node)
|| NodeGuards.isContinueStatementNode(node);
const isVariableDeclarationWithLetOrConstKind: boolean = NodeGuards.isVariableDeclarationNode(node)
&& (node.kind === 'const' || node.kind === 'let');
const isClassDeclaration: boolean = NodeGuards.isClassDeclarationNode(node);
return NodeGuards.isFunctionDeclarationNode(node)
|| isBreakOrContinueStatement
|| isVariableDeclarationWithLetOrConstKind
|| isClassDeclaration;
}
/**
* @param {BlockStatement} blockStatementNode
* @returns {boolean}
*/
private static canTransformBlockStatementNode (blockStatementNode: ESTree.BlockStatement): boolean {
let canTransform: boolean = true;
estraverse.traverse(blockStatementNode, {
enter: (node: ESTree.Node): estraverse.VisitorOption | void => {
if (NodeGuards.isWhileStatementNode(node)) {
return estraverse.VisitorOption.Skip;
}
if (BlockStatementControlFlowTransformer.isProhibitedStatementNode(node)) {
canTransform = false;
}
}
});
if (blockStatementNode.body.length <= 4) {
canTransform = false;
}
return canTransform;
}
/**
* @param {TransformationStage} transformationStage
* @returns {IVisitor | null}
*/
public getVisitor (transformationStage: TransformationStage): IVisitor | null {
switch (transformationStage) {
case TransformationStage.ControlFlowFlattening:
return {
leave: (node: ESTree.Node, parentNode: ESTree.Node | null): ESTree.Node | undefined => {
if (parentNode && NodeGuards.isBlockStatementNode(node)) {
return this.transformNode(node, parentNode);
}
}
};
default:
return null;
}
}
/**
* @param {BlockStatement} blockStatementNode
* @param {NodeGuards} parentNode
* @returns {NodeGuards}
*/
public transformNode (blockStatementNode: ESTree.BlockStatement, parentNode: ESTree.Node): ESTree.Node {
if (
this.randomGenerator.getMathRandom() > this.options.controlFlowFlatteningThreshold ||
!BlockStatementControlFlowTransformer.canTransformBlockStatementNode(blockStatementNode)
) {
return blockStatementNode;
}
const blockStatementBody: ESTree.Statement[] = blockStatementNode.body;
const originalKeys: number[] = this.arrayUtils.createWithRange(blockStatementBody.length);
const shuffledKeys: number[] = this.arrayUtils.shuffle(originalKeys);
const originalKeysIndexesInShuffledArray: number[] = originalKeys.map((key: number) => shuffledKeys.indexOf(key));
const blockStatementControlFlowFlatteningCustomNode: ICustomNode<TInitialData<BlockStatementControlFlowFlatteningNode>> =
this.controlFlowCustomNodeFactory(ControlFlowCustomNode.BlockStatementControlFlowFlatteningNode);
blockStatementControlFlowFlatteningCustomNode.initialize(
blockStatementBody,
shuffledKeys,
originalKeysIndexesInShuffledArray
);
const newBlockStatementNode: TStatement = blockStatementControlFlowFlatteningCustomNode.getNode()[0];
NodeUtils.parentizeNode(newBlockStatementNode, parentNode);
return newBlockStatementNode;
}
}