All files / src/node-obfuscators FunctionObfuscator.ts

100% Statements 23/23
100% Branches 4/4
100% Functions 4/4
100% Lines 23/23
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 831x           1x   1x 1x 1x 1x                   1x                     17683x   17683x             17683x 17683x             17683x   12131x 12131x                 17683x   936151x 273592x   273592x 37382x 37382x           17683x   12131x     17683x      
import * as estraverse from 'estraverse';
import * as ESTree from 'estree';
 
import { ICustomNode } from '../interfaces/custom-nodes/ICustomNode';
import { IOptions } from '../interfaces/IOptions';
 
import { NodeType } from '../enums/NodeType';
 
import { AbstractNodeObfuscator } from './AbstractNodeObfuscator';
import { IdentifierReplacer } from './replacers/IdentifierReplacer';
import { Node } from '../node/Node';
import { NodeUtils } from '../node/NodeUtils';
 
/**
 * replaces:
 *     function foo (argument1) { return argument1; };
 *
 * on:
 *     function foo (_0x12d45f) { return _0x12d45f; };
 *
 */
export class FunctionObfuscator extends AbstractNodeObfuscator {
    /**
     * @type {IdentifierReplacer}
     */
    private identifierReplacer: IdentifierReplacer;
 
    /**
     * @param nodes
     * @param options
     */
    constructor(nodes: Map <string, ICustomNode>, options: IOptions) {
        super(nodes, options);
 
        this.identifierReplacer = new IdentifierReplacer(this.nodes, this.options);
    }
 
    /**
     * @param functionNode
     */
    public obfuscateNode (functionNode: ESTree.Function): void {
        this.storeFunctionParams(functionNode);
        this.replaceFunctionParams(functionNode);
    }
 
    /**
     * @param functionNode
     */
    private storeFunctionParams (functionNode: ESTree.Function): void {
        functionNode.params
            .forEach((paramsNode: ESTree.Node) => {
                NodeUtils.typedReplace(paramsNode, NodeType.Identifier, {
                    enter: (node: ESTree.Identifier) => this.identifierReplacer.storeNames(node.name)
                });
            });
    }
 
    /**
     * @param functionNode
     */
    private replaceFunctionParams (functionNode: ESTree.Function): void {
        let replaceVisitor: estraverse.Visitor = {
            enter: (node: ESTree.Node, parentNode: ESTree.Node): any => {
                if (Node.isReplaceableIdentifierNode(node, parentNode)) {
                    const newNodeName: string = this.identifierReplacer.replace(node.name);
 
                    if (node.name !== newNodeName) {
                        node.name = newNodeName;
                        node.obfuscated = true;
                    }
                }
            }
        };
 
        functionNode.params
            .forEach((paramsNode: ESTree.Node) => {
                estraverse.replace(paramsNode, replaceVisitor);
            });
 
        estraverse.replace(functionNode.body, replaceVisitor);
    }
}