Code coverage report for src/node-transformers/obfuscating-transformers/VariableDeclarationTransformer.ts

# All files / src/node-transformers/obfuscating-transformers VariableDeclarationTransformer.ts

100% Statements 44/44
100% Branches 16/16
100% Functions 5/5
100% Lines 41/41

    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
    83
    84
    85
    86
    87
    88
    89
    90
    91
    92
    93
    94
    95
    96
    97
    98
    99
    100
    101
    102
    103
    104
    105
    106
    107
    108
    109
    110
    111
    112
    113
    114
    115
    116
    117
    118
    119
    120
    121
    122
    123
    124
    125
    126
    127
    128
    129
    130
    131
    132
    133
    134
    135
    136
    137
    138
    139
    140
    141
    142
    143
    144
    145
    146
    147
    148
    149
    150
    151
    1521x
    1x

    1x

    1x
    1x

    1x
    1x
    1x

    1x

    6262x

    6262x

    6262x

    6262x

    665151x
    31571x

    31571x

    31571x
    1780x

    29791x
    29791x

    29791x

    29791x
    14994x

    14797x

    29791x

    29791x

    33985x
    1x

    33984x
    33985x

    14994x

    14994x
    717351x

    14797x

    14797x

    1011840x
    274700x

    274700x
    42070x

    232630x

    14797x

     import { injectable, inject } from 'inversify';
    import { ServiceIdentifiers } from '../../container/ServiceIdentifiers';

    import * as estraverse from 'estraverse';
    import * as ESTree from 'estree';

    import { TNodeWithBlockStatement } from '../../types/node/TNodeWithBlockStatement';
    import { TObfuscationReplacerFactory } from '../../types/container/TObfuscationReplacerFactory';

    import { IOptions } from '../../interfaces/options/IOptions';
    import { IObfuscationReplacerWithStorage } from '../../interfaces/node-transformers/IObfuscationReplacerWithStorage';
    import { IVisitor } from '../../interfaces/IVisitor';

    import { ObfuscationReplacers } from '../../enums/container/ObfuscationReplacers';
    import { NodeType } from '../../enums/NodeType';

    import { AbstractNodeTransformer } from '../AbstractNodeTransformer';
    import { Node } from '../../node/Node';
    import { NodeUtils } from '../../node/NodeUtils';

    /**
     * replaces:
     *     var variable = 1;
     *     variable++;
     *
     * on:
     *     var _0x12d45f = 1;
     *     _0x12d45f++;
     *
     */
    @injectable()
    export class VariableDeclarationTransformer extends AbstractNodeTransformer {
        /**
         * @type {IObfuscationReplacerWithStorage}
         */
        private readonly identifierReplacer: IObfuscationReplacerWithStorage;

        /**
         * @type {Map<ESTree.Node, ESTree.Identifier[]>}
         */
        private readonly replaceableIdentifiers: Map <ESTree.Node, ESTree.Identifier[]> = new Map();

        /**
         * @param obfuscationReplacerFactory
         * @param options
         */
        constructor (
            @inject(ServiceIdentifiers.Factory__IObfuscationReplacer) obfuscationReplacerFactory: TObfuscationReplacerFactory,
            @inject(ServiceIdentifiers.IOptions) options: IOptions
        ) {
            super(options);

            this.identifierReplacer = <IObfuscationReplacerWithStorage>obfuscationReplacerFactory(ObfuscationReplacers.IdentifierReplacer);
        }

        /**
         * @return {IVisitor}
         */
        public getVisitor (): IVisitor {
            return {
                enter: (node: ESTree.Node, parentNode: ESTree.Node) => {
                    if (Node.isVariableDeclarationNode(node)) {
                        return this.transformNode(node, parentNode);
                    }
                }
            };
        }

        /**
         * @param variableDeclarationNode
         * @param parentNode
         * @returns {ESTree.Node}
         */
        public transformNode (variableDeclarationNode: ESTree.VariableDeclaration, parentNode: ESTree.Node): ESTree.Node {
            const blockScopeOfVariableDeclarationNode: TNodeWithBlockStatement = NodeUtils
                .getBlockScopesOfNode(variableDeclarationNode)[0];

            if (blockScopeOfVariableDeclarationNode.type === NodeType.Program) {
                return variableDeclarationNode;
            }

            const nodeIdentifier: number = this.nodeIdentifier++;
            const scopeNode: ESTree.Node = variableDeclarationNode.kind === 'var'
                ? blockScopeOfVariableDeclarationNode
                : parentNode;

            this.storeVariableNames(variableDeclarationNode, nodeIdentifier);

            // check for cached identifiers for current scope node. If exist - loop through them.
            if (this.replaceableIdentifiers.has(scopeNode)) {
                this.replaceScopeCachedIdentifiers(scopeNode, nodeIdentifier);
            } else {
                this.replaceScopeIdentifiers(scopeNode, nodeIdentifier);
            }

            return variableDeclarationNode;
        }

        /**
         * @param variableDeclarationNode
         * @param nodeIdentifier
         */
        private storeVariableNames (variableDeclarationNode: ESTree.VariableDeclaration, nodeIdentifier: number): void {
            variableDeclarationNode.declarations
                .forEach((declarationNode: ESTree.VariableDeclarator) => {
                    if (Node.isObjectPatternNode(declarationNode.id)) {
                        return estraverse.VisitorOption.Skip;
                    }

                    NodeUtils.typedTraverse(declarationNode.id, NodeType.Identifier, {
                        enter: (node: ESTree.Identifier) => this.identifierReplacer.storeNames(node.name, nodeIdentifier)
                    });
                });
        }

        /**
         * @param scopeNode
         * @param nodeIdentifier
         */
        private replaceScopeCachedIdentifiers (scopeNode: ESTree.Node, nodeIdentifier: number): void {
            const cachedReplaceableIdentifiers: ESTree.Identifier[] = <ESTree.Identifier[]>this.replaceableIdentifiers.get(scopeNode);

            cachedReplaceableIdentifiers.forEach((replaceableIdentifier: ESTree.Identifier) => {
                replaceableIdentifier.name = this.identifierReplacer.replace(replaceableIdentifier.name, nodeIdentifier);
            });
        }

        /**
         * @param scopeNode
         * @param nodeIdentifier
         */
        private replaceScopeIdentifiers (scopeNode: ESTree.Node, nodeIdentifier: number): void {
            const storedReplaceableIdentifiers: ESTree.Identifier[] = [];

            estraverse.replace(scopeNode, {
                enter: (node: ESTree.Node, parentNode: ESTree.Node): any => {
                    if (!node.obfuscatedNode && Node.isReplaceableIdentifierNode(node, parentNode)) {
                        const newNodeName: string = this.identifierReplacer.replace(node.name, nodeIdentifier);

                        if (node.name !== newNodeName) {
                            node.name = newNodeName;
                        } else {
                            storedReplaceableIdentifiers.push(node);
                        }
                    }
                }
            });

            this.replaceableIdentifiers.set(scopeNode, storedReplaceableIdentifiers);
        }
    }