javascript-obfuscator/test/functional-tests/node-transformers/dead-code-injection-transformers/DeadCodeInjectionTransformer.spec.ts

import { assert } from 'chai';

import { IObfuscationResult } from '../../../../src/interfaces/IObfuscationResult';

import { NO_CUSTOM_NODES_PRESET } from '../../../../src/options/presets/NoCustomNodes';

import { readFileAsString } from '../../../helpers/readFileAsString';

import { JavaScriptObfuscator } from '../../../../src/JavaScriptObfuscator';

describe('DeadCodeInjectionTransformer', () => {
    const variableMatch: string = '_0x([a-f0-9]){4,6}';
    const hexMatch: string = '0x[a-f0-9]';

    describe('transformNode (programNode: ESTree.Program, parentNode: ESTree.Node): ESTree.Node', () => {
        describe('variant #1 - 5 simple block statements', () => {
            const obfuscationResult: IObfuscationResult = JavaScriptObfuscator.obfuscate(
                readFileAsString(__dirname + '/fixtures/input-1.js'),
                {
                    ...NO_CUSTOM_NODES_PRESET,
                    deadCodeInjection: true,
                    deadCodeInjectionThreshold: 1,
                    stringArray: true,
                    stringArrayThreshold: 1
                }
            );
            const obfuscatedCode: string = obfuscationResult.getObfuscatedCode();
            const deadCodeMatch: string = `` +
                `if *\\(${variableMatch}\\('${hexMatch}'\\) *[=|!]== *${variableMatch}\\('${hexMatch}'\\)\\) *\\{`+
                    `console\\[${variableMatch}\\('${hexMatch}'\\)\\]\\(${variableMatch}\\('${hexMatch}'\\)\\);` +
                `\\} *else *\\{`+
                    `console\\[${variableMatch}\\('${hexMatch}'\\)\\]\\(${variableMatch}\\('${hexMatch}'\\)\\);` +
                `\\}` +
            ``;
            const regexp: RegExp = new RegExp(deadCodeMatch, 'g');
            const matches: RegExpMatchArray = <RegExpMatchArray>obfuscatedCode.match(regexp);

            it('should replace block statements with condition with original block statements and dead code', () => {
                assert.isNotNull(matches);
                assert.equal(matches.length, 5);
            });
        });

        describe('variant #2 - 4 simple block statements', () => {
            const obfuscationResult: IObfuscationResult = JavaScriptObfuscator.obfuscate(
                readFileAsString(__dirname + '/fixtures/block-statements-min-count.js'),
                {
                    ...NO_CUSTOM_NODES_PRESET,
                    deadCodeInjection: true,
                    deadCodeInjectionThreshold: 1,
                    stringArray: true,
                    stringArrayThreshold: 1
                }
            );
            const obfuscatedCode: string = obfuscationResult.getObfuscatedCode();
            const codeMatch: string = `` +
                `var *${variableMatch} *= *function *\\(\\) *\\{` +
                    `console\\[${variableMatch}\\('${hexMatch}'\\)\\]\\(${variableMatch}\\('${hexMatch}'\\)\\);` +
                `\\};` +
            ``;
            const regexp: RegExp = new RegExp(codeMatch, 'g');
            const matches: RegExpMatchArray = <RegExpMatchArray>obfuscatedCode.match(regexp);

            it('shouldn\'t add dead code if block statements count is less than 5', () => {
                assert.isNotNull(matches);
                assert.equal(matches.length, 4);
            });
        });

        describe('variant #3 - deadCodeInjectionThreshold: 0', () => {
            const obfuscationResult: IObfuscationResult = JavaScriptObfuscator.obfuscate(
                readFileAsString(__dirname + '/fixtures/input-1.js'),
                {
                    ...NO_CUSTOM_NODES_PRESET,
                    deadCodeInjection: true,
                    deadCodeInjectionThreshold: 0,
                    stringArray: true,
                    stringArrayThreshold: 1
                }
            );
            const obfuscatedCode: string = obfuscationResult.getObfuscatedCode();
            const codeMatch: string = `` +
                `var *${variableMatch} *= *function *\\(\\) *\\{` +
                    `console\\[${variableMatch}\\('${hexMatch}'\\)\\]\\(${variableMatch}\\('${hexMatch}'\\)\\);` +
                `\\};` +
            ``;
            const regexp: RegExp = new RegExp(codeMatch, 'g');
            const matches: RegExpMatchArray = <RegExpMatchArray>obfuscatedCode.match(regexp);

            it('shouldn\'t add dead code if `deadCodeInjectionThreshold` option value is `0`', () => {
                assert.isNotNull(matches);
                assert.equal(matches.length, 5);
            });
        });

        describe('variant #4 - break or continue statement in block statement', () => {
            const obfuscationResult: IObfuscationResult = JavaScriptObfuscator.obfuscate(
                readFileAsString(__dirname + '/fixtures/break-continue-statement.js'),
                {
                    ...NO_CUSTOM_NODES_PRESET,
                    deadCodeInjection: true,
                    deadCodeInjectionThreshold: 1,
                    stringArray: true,
                    stringArrayThreshold: 1
                }
            );
            const obfuscatedCode: string = obfuscationResult.getObfuscatedCode();

            const functionMatch: string = `` +
                `var *${variableMatch} *= *function *\\(\\) *\\{` +
                    `console\\[${variableMatch}\\('${hexMatch}'\\)\\]\\(${variableMatch}\\('${hexMatch}'\\)\\);` +
                `\\};` +
            ``;
            const loopMatch: string = `` +
                `for *\\(var *${variableMatch} *= *${hexMatch}; *${variableMatch} *< *${hexMatch}; *${variableMatch}\\+\\+\\) *\\{` +
                    `(?:continue|break);` +
                `\\}` +
            ``;

            const functionRegExp: RegExp = new RegExp(functionMatch, 'g');
            const loopRegExp: RegExp = new RegExp(loopMatch, 'g');

            const functionMatches: RegExpMatchArray = <RegExpMatchArray>obfuscatedCode.match(functionRegExp);
            const loopMatches: RegExpMatchArray = <RegExpMatchArray>obfuscatedCode.match(loopRegExp);

            it('shouldn\'t add dead code if block statement contains `continue` or `break` statements', () => {
                assert.isNotNull(functionMatches);
                assert.isNotNull(loopMatches);

                assert.equal(functionMatches.length, 4);
                assert.equal(loopMatches.length, 2);
            });
        });
    });
});