JavaScript obfuscation method based on syntax tree AST editing

Abstract

A JavaScript obfuscation method based on syntax tree AST editing comprises the following steps that JavaScript source codes are compressed to remove redundant codes, and an AST syntax tree is generated through analysis; traversing the AST syntax tree, and editing and converting the grammar in the AST syntax tree; creating an array array A, extracting a character string of the AST syntax tree, and converting the character string into a data dictionary of a two-dimensional array through a specific algorithm; a decoding method is created, and the decoding method and the random redundancy method are randomly inserted into the array A in the previous step; creating a self-execution method funtionF, transmitting the parameters of the two-dimensional array array A as arguments into the self-execution method funtionF, and combining the decoding method with the self-execution method funtionF to generate a new AST syntax tree; all character string nodes in the original AST syntax tree are converted into a decoding method Function H; the original AST syntax tree is inserted into the new AST syntax tree to replace all digits and variables, and the new AST syntax tree of a brand new structure is obtained; the new AST syntax tree is restored into the JavaScript code, and after blank space line feed compression is removed, the JavaScript code is output to obtain an obfuscated code.

Description

technical field [0001] The invention relates to the technical field of computer and communication, in particular to a JavaScript obfuscation method implemented based on syntax tree AST editing. Background technique [0002] JavaScript is a programming language that runs on web browsers. It is mainly added to websites built using HTML (Hyper Text Markup Language) and CSS (Cascading Style Sheets). The role of page dynamic effects. For example, the effect of the carousel image displayed on the webpage and the prompt information displayed after the wrong content is entered on the consulting platform. In addition, when purchasing products on the mall website, JavaScript is also required for using the shopping cart and cost estimation. So even if it’s not obvious, it’s still a language that coders use a lot, and JavaScript is the most important programming language for front-end web development. [0003] In the early days of web (World Wide Web, global wide area network, also k...

AI Technical Summary

Problems solved by technology

[0008] Although "code obfuscation" is safer and more flexible than the other two, it still has major disadvantages

Common code obfuscation is obfuscated by methods such as renaming local variables, constant replacement, and simple string transcoding, but strings such as attribute values ​​and object method names / attribute names still appear in the code, which is easy for experienced attackers Guess the code and the functions involved to crack it

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