Ios obfuscation Hello, I am working on kmm librar...

# multiplatform

[Jakub Sieprawski]

Ios obfuscation

Hello, I am working on kmm library for ios and android platform. I'm trying to find a way to obfuscate ios library. I found this tutorial - https://medium.com/@dfs.techblog/code-obfuscations-in-kotlin-multiplatform-kmp-494d2cd0a416 in which someone is modifying linker options to strip all on used symbols. When I am trying to modify my build script this way i am getting this warning and errors:
w: Flag is not supported by this version of the compiler: -Xobfuscate
ld: unknown options: -Xlinker -Xlinker -Xlinker --strip-debug -Xlinker --strip-unneeded -Xlinker --strip-all

I am using Xcode 15.4, AGP 2.0.20.
Any suggestions on how to fix this? Or any other ideas how to obfuscate ios xcframework generated using KMM?

[Jakub Sieprawski]

Any ideas? I would really appreciaty any help

[François]

The default release mode is not enough for you? How do you check the content?

[Jakub Sieprawski]

Nope, its not enough. When I am using command nm -g on final, release binary I can see a lot of unnecessary symbols that i would like to get rid of. Is it possible somehow?

[François]

The content exposed are what inside the objc header used by your iOS app, means everything exposed publicly from your kotlin code

[François]

if you want to reduce the exposed content set the visibility of your kotlin code at internal

[François]

Use something like explicitApi() to control what you want to expose

[Jakub Sieprawski]

Okay, but what about frameworks that are statically linked. In my KMP project I am using openssl which is linked statically and in final binary i also can see symbols from openssl. I don't want them there. How can i change visibility of openssl symbols?

[François]

Changing the visibility of your class/properties to internal will remove them to the “nm -g” list

[François]

if one of your public properties use openssl, openssl will be exposed, even with the coroutine

[François]

Just make a simple app with explicitapi enabled and play with the visibility

[François]

Swift module are internal by default and kotlin module are open by default