dalvik bytecode optimization method based on memory loading

Abstract

The invention discloses a method for optimizing dalvik byte codes on the basis of memory loading. The method includes steps of 1, decrypting and decompressing read encrypted DEX (developing excellence) files and then storing the decrypted and decompressed DEX files in stack memories in byte code forms; 2, parsing byte codes of the DEX files obtained at the step 1 by the aid of openDexFile processes for reflecting and invoking DexFile to obtain a DexOrJar structures, loading contents of the DexOrJar structure into hash tables of userDexFile structures in gDvm, returning DexOrJar structure pointers with stored DEX file information and denoting the DexOrJar structure pointers as cookie values; 3, defining local processes loadDex and transmitting byte arrays and byte sizes of the DEX files; 4, rewriting class loaders and loading specified classes. The method has the advantages that the DEX files are decrypted, decompressed, stored and loaded in the memories in the byte code forms all along after being read, encrypted and compressed, and can be protected to a great extent, and accordingly the anti-attack performance of reinforced APK (Android packages) can be improved.

Description

technical field [0001] The invention relates to the field of mobile terminal application security, in particular to a dalvik bytecode optimization method based on memory loading. Background technique [0002] According to the latest sales statistics of smart terminals, China's Android system has occupied more than 73% of the mobile terminal market share, and various Android applications are also growing exponentially and involving more and more businesses, covering entertainment, payment, life, etc. each field. Since the language used by the android platform software is JAVA, and the binary code compiled from the JAVA source code is very easy to be decompiled, the android application program is easily damaged by hackers through secondary packaging, tampering, malicious injection and other means. Therefore, application security issues have become a hot spot for developers / publishers / users. [0003] At present, the mainstream application software hardening measures in the ma...

AI Technical Summary

Problems solved by technology

First of all, the decrypted dex file needs to be stored in a specific directory, which increases the risk of being cracked

Secondly, first decrypt the dex of the source program, and then use DexClassLoader to load it, which is equivalent to loading the dex into the memory twice when decrypting and loading the original dex, which greatly reduces the startup efficiency of the program

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