InspectiveC

MobileSubstrate based objc_msgSend hook for debugging/inspection purposes.

Based on itrace by emeau, AspectiveC by saurik, and Subjective-C by kennytm.

Logs output to /var/mobile/Documents/InspectiveC or /var/mobile/Containers/Data/Application/<App-Hex>/Documents/InspectiveC (sandbox). Inside the InspectiveC folder, you'll find <exe>/<pid>_<tid>.log.

You can download the deb from the stable_debs folder or from my repo.

Description:

This is an inspection tool that you can use to log Objective-C message hierarchies. It can currently watch specific objects, all objects of a given class, and specific selectors. It is indeed compatible with arm64 - in fact, it is more full-featured on arm64 as arm32 has obj_msgSend[st|fp]ret which are currently not hooked.

Features:

• arm64 support (and arm32)
• Watch specific objects
• Watch instances of a specific class
• Watch specific selectors
• Prints arguments

Hopeful Features (in no particular order):

• Print retvals
• Hook obj_msgSend[st|fp]ret
• More advanced filtering
• Optimizations
  • Nicer hooking
  • Reduce redundancy
  • Better multithreading performance

Example Output:

***-|SpringBoard@<0x15455d320> _run|***
  +|NSAutoreleasePool alloc|
    +|NSAutoreleasePool allocWithZone:| NULL
  -|NSAutoreleasePool@<0x170442a00> init|
  -|SpringBoard@<0x15455d320> _accessibilityInit|
    -|SpringBoard@<0x15455d320> performSelector:withObject:afterDelay:| @selector(_accessibilitySetUpQuickSpeak) nil 1.5
      +|NSArray arrayWithObject:| @"kCFRunLoopDefaultMode"
      -|SpringBoard@<0x15455d320> performSelector:withObject:afterDelay:inModes:| @selector(_accessibilitySetUpQuickSpeak) nil 1.5 <__NSArrayI@0x174233560>
    -|SpringBoard@<0x15455d320> _updateAccessibilitySettingsLoader|
      +|NSBundle mainBundle|
      -|NSBundle@<0x17009f310> bundleIdentifier|
      -|__NSCFString@<0x1740557b0> isEqualToString:| @"com.apple.PreBoard"
      -|__NSStackBlock__@<0x16fdb7608> copy|
      +|CFPrefsSearchListSource withSearchListForIdentifier:container:perform:| 0x19819f3b0 NULL <__NSStackBlock__@0x16fdb7570>
      +|NSNumber class|
      -|__NSCFBoolean@<0x194d4ab70> isKindOfClass:| [NSNumber class]
      -|__NSCFBoolean@<0x194d4ab70> boolValue|
      -|__NSCFBoolean@<0x194d4ab70> release|
    -|SpringBoard@<0x15455d320> _updateApplicationAccessibility|
      +|NSBundle mainBundle|
      -|NSBundle@<0x17009f310> bundleIdentifier|
      -|__NSCFString@<0x1740557b0> isEqualToString:| @"com.apple.PreBoard"
      -|__NSStackBlock__@<0x16fdb75f8> copy|
      +|CFPrefsSearchListSource withSearchListForIdentifier:container:perform:| 0x19819f3b0 NULL <__NSStackBlock__@0x16fdb7560>
      +|NSNumber class|
      -|__NSCFNumber@<0xb000000000000003> isKindOfClass:| [NSNumber class]
      -|__NSCFNumber@<0xb000000000000003> boolValue|
      -|__NSCFNumber@<0xb000000000000003> release|
    -|SpringBoard@<0x15455d320> _updateLargeTextNotification|...

Usage:

Properly install theos and grab yourself a copy of the iOS SDK. You may have to modify the Makefile (i.e. ARCHS or TARGET) and/or InspectiveC.mm. I compile this on my Mac with Clang - if you use anything different you may have some issues with the assembly code.

When you install the deb, you will find libinspectivec.dylib in /usr/lib. Copy this dylib into $THEOS/lib and then copy InspectiveC.h into $THEOS/include.

Option 1: Use the InspectiveC Wrapper

Include InspCWrapper.m in your Tweak file. You should probably use a DEBUG guard.

#if INSPECTIVEC_DEBUG
#include "InspCWrapper.m"
#endif

Then use the following API:

// Set the maximum logging depth after a hit.
void setMaximumRelativeLoggingDepth(int depth);

// Watches/unwatches the specified object. Objects will be automatically unwatched when they
// receive a -|dealloc| message.
void watchObject(id obj);
void unwatchObject(id obj);

// Watches/unwatches instances of the specified class ONLY - will not watch subclass instances.
void watchClass(Class clazz);
void unwatchClass(Class clazz);

// Watches/unwatches the specified selector.
void watchSelector(SEL _cmd);
void unwatchSelector(SEL _cmd);

// Enables/disables logging for the current thread.
void enableLogging();
void disableLogging();

Option 2: Link directly against InspectiveC

Add the following line to your makefile:

<YOUR_TWEAK_NAME>_LIBRARIES = inspectivec

This will automatically load InspectiveC in your tweak (whatever process your tweak injects into). Then include InspectiveC.h in your tweak and use those functions.

InspectiveC.h headlines the following API:

// Set the maximum logging depth after a hit.
void InspectiveC_setMaximumRelativeLoggingDepth(int depth);

// Watches/unwatches the specified object. Objects will be automatically unwatched when they
// receive a -|dealloc| message.
void InspectiveC_watchObject(id obj);
void InspectiveC_unwatchObject(id obj);

// Watches/unwatches instances of the specified class ONLY - will not watch subclass instances.
void InspectiveC_watchInstancesOfClass(Class clazz);
void InspectiveC_unwatchInstancesOfClass(Class clazz);

// Watches/unwatches the specified selector.
void InspectiveC_watchSelector(SEL _cmd);
void InspectiveC_unwatchSelector(SEL _cmd);

// Enables/disables logging for the current thread.
void InspectiveC_enableLogging();
void InspectiveC_disableLogging();