A basic introduction to what a jailbreak really *is*, and how to remix software by writing your own jailbreak tweaks. See http://overooped.com/post/75523688909/writing-your-own-jailbreak-tweak for presenter notes

1. Jailbreak
Development
!
nevyn@lookback.io
!
CocoaHeads Stockholm 2014-02-03

2. Jailbreak development

4. Jailbreak development

6. App sandbox

7. mobile user
App sandbox

8. root access
mobile user
App sandbox

9. write access to operating system files
root access
mobile user
App sandbox

10. !
Your Software

11. Remixing!
Your Software

12. Jailbreak development

13. $ the0s
$ make
$ make install

15. iod-setup sdk -d /Applications/Xcode.app/
Contents/Developer -sdk iphoneos

30. swizzling
is
art

31. Logos tweak
MyTweak.x
%hook SBApplicationController!
-(void)uninstallApplication:(SBApplication *)application {!
NSLog(@"Hey, we're hooking uninstallApplication:!");!
%orig; // Call the original implementation of this method!
return;!
}!
%end!

32. CaptainHook tweak
MyTweak.mm
#import <CaptainHook/CaptainHook.h>
!
CHDeclareClass(NSString);
CHMethod(2, void, NSString, writeToFile, NSString *, path, atomically, BOOL, flag)
{
NSLog(@"Writing string to %@: %@", path, self);
CHSuper(2, NSString, writeToFile, path, atomically, flag);
}
!
CHConstructor
{
CHLoadClass(NSString);
CHHook(2, NSString, writeToFile, atomically);
}

33. Live coding
ListClasses

34. class-dump

35. !
@interface Area : Thing!
{!
NSString *title;!
int type;!
NSDate *reviewedDate;!
NSMutableSet *tags;!
NSMutableDictionary *sharedLists;!
}!
@interface RepeatingTask : Task!
{!
TH1RecurrenceRule *_recurrenceRule;!
BOOL _instanceCreationPaused;!
NSDate *_instanceCreationStartDate;!
int _instanceCreationCount;!
NSDate *_afterCompletionReferenceDate;!
}!
+
-
+
+
+
+
+
+
+
-
!
(int)mergeRuleForProperty:(id)fp8;!
(id)reviewedDate;!
(int)type;!
(id)title;!
(void)removeTask:(id)fp8;!
(void)pigeonholeTask:(id)fp8;!
(id)sharedListContainingTask:(id)fp8;!
(id)sharedListWithIdentifier:(id)fp8;!
(BOOL)matchesTag:(id)fp8;!
(id)inheritedTags;!
(id)allTags;!
(BOOL)hasTags;!
(BOOL)hasElements;!
(unsigned int)countOfElements;!
(void)save;!
(id)initFromDatabaseWithUUID:(id)fp8;!
(void)dealloc;!
(id)init;!
(void)setTags:(id)fp8;!
(id)tags;!
(void)setReviewedDate:(id)fp8;!
(void)setTitle:(id)fp8;!
(void)setType:(int)fp8;!
(void)mergeValue:(id)fp8 touched:(id)fp12 forKey:(id)fp16;!
!
@end!
!
@interface Contact : _AudioServicesAddSystemSoundCompletion!
{!
}!
!
- (id)uuid;!
!
@end!
!
!
(id)_createRepeatingInstanceFromTask:(id)fp8 forDate:(id)fp12;!
(id)_createInstanceFromTask:(id)fp8 forDate:(id)fp12 withIdentifierDate
(id)allKeysForSync;!
(id)keysForInitialization;!
(id)keysForCreation;!
(id)newKeys;!
(void)load;!
(int)createInstancesIfNecessary:(int)fp8 all:(int)fp12;!
(id)recurrenceStartDatesFromDate:(id)fp8 count:(int)fp12;!
(void)updateAfterCompletionStatus;!
(void)instanceWasUnstopped:(id)fp8;!
(void)instanceWasStopped:(id)fp8;!
(void)instanceWasDeleted:(id)fp8;!
(void)instanceWillBeDeleted:(id)fp8;!
(BOOL)createsDueDates;!
(int)state;!
(BOOL)instanceCreationEnded;!
(id)lastInstance;!
(id)instances;!
(void)setAfterCompletionReferenceDate:(id)fp8;!
(id)afterCompletionReferenceDate;!
(void)setInstanceCreationCount:(int)fp8;!
(int)instanceCreationCount;!
(void)setInstanceCreationStartDate:(id)fp8;!
(id)instanceCreationStartDate;!
(void)setInstanceCreationPaused:(BOOL)fp8;!
(BOOL)instanceCreationPaused;!
(void)setRecurrenceRule:(id)fp8;!
(id)recurrenceRule;!
(BOOL)isRepeating;!
(BOOL)save;!
(void)setPrimitiveValues:(id)fp8 forKeys:(id)fp12;!
(void)dealloc;!
(id)initWithUUID:(id)fp8;!
(id)init;!
(void)_commonInit;!
@end!

36. • install “Clutch” package from
iphonecake.com
• Clutch Appname
• Unzip
• class-dump Appname

37. Please don’t pirate
apps :(

38. Live coding
class-dump

39. Install

40. default password: alpine

43. ⌘⇧-I
Install tweak to device from
Xcode/iOSOpenDev

44. github.com/rpetrich/
deviceconsole

48. http://repo.nevyn.nu

49. Thanks for listening!
@nevyn
@lookback