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@yehgdotnet
Created April 27, 2021 13:01
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Debugging symbols
Purpose: To prevent deobfuscation
Symbols are usually stripped during the build process, so you need the compiled byte-code and libraries to verify whether any unnecessary metadata has been discarded.
First find the nm binary in your Android NDK and export it (or create an alias).
export $NM = $ANDROID_NDK_DIR/toolchains/arm-linux-androideabi-4.9/prebuilt/darwin-x86_64/bin/arm-linux-androideabi-nm
To display debug symbols:
$ $NM -a libfoo.so
/tmp/toolchains/arm-linux-androideabi-4.9/prebuilt/darwin-x86_64/bin/arm-linux-androideabi-nm: libfoo.so: no symbols
To display dynamic symbols:
$ $NM -D libfoo.so
Alternatively, open the file in your favorite disassembler and check the symbol tables manually.
Dynamic symbols can be stripped using the visibility compiler flag. Adding this flag causes gcc to discard the function names while still preserving the names of functions declared as JNIEXPORT.
Check if the following was added to build.gradle:
externalNativeBuild {
cmake {
cppFlags "-fvisibility=hidden"
}
}
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