Why lldb seems to not stop at breakpoints?

Question

While reverse engineering an iPhone app remotely, I set up breakpoints to some function's adresses.

These adresses comes from the disassembled binary analysed with Hopper, and it seems like they must be called by the app. Like user_click_on_blue_buton, or equivalent.

I checked that the breakpoint are set up correctly:

• none is in pending state,
• all have the flag resolved to true: resolved = 1,
• and the disassembled code at these addresses is the same as in the binary statically analysed with Hopper.

But then, when I click on the blue button, lldb does not stop at breakpoint. The process continues like there was no breakpoints. To be exact, some are working, but just a few, not all of them.

Is it possible that lldb misses the breakpoint ? Or is it because the app is tricking me and these functions are not called ?

Obviously the app is a released iOS app from the app store. So definitely not compiled to be debugged. Is it the reason ?

Answer 1

Because the functions were never called.

The app indeed tricked me. It's not because a function is named user_click_on_blue_button that it will be called when the user click on the blue button. Another function, with a less obvious name, was used instead.

Can't find my previous account, so using a new one.