#nskeyedarchiver

NSKeyedArchiver

NSUserDefaults

를 이용할수 있다.

Apple iOS / MacOS NSKeyedArchiver Heap Corruption

Apple iOS / MacOS suffers from a NSKeyedArchiver heap corruption vulnerability due to a rounding error in TIKeyboardLayout initWithCoder:. Source: Apple iOS / MacOS NSKeyedArchiver Heap Corruption The post Apple iOS / MacOS NSKeyedArchiver Heap Corruption appeared first on MondoUnix.

Apple iOS / OS X NSKeyedArchiver Memory Corruption

Apple iOS / OS X suffer from a NSKeyedArchiver memory corruption vulnerability due to a lack of bounds checking in CAMediaTimingFunctionBuiltin. Source: Apple iOS / OS X NSKeyedArchiver Memory Corruption The post Apple iOS / OS X NSKeyedArchiver Memory Corruption appeared first on MondoUnix.

The NSCoding protocol declares the two methods that a class must implement so that instances of that class can be encoded and decoded. This capability provides the basis for archiving and distribution. In other words, the basis for serialize and deserialize objects.

Use the NSCoding is easy.

Your class must implement the NSCoding protocol into the .h file.  Into the .m you must implement the methods initWithCode: and encodeWithCoder:.

That is like below:

#import <Foundation/Foundation.h> @interface Organism : NSObject <NSCoding> //properties goes here -(void)saveToDiskWithKey:(NSString *)key; +(id)loadFromDiskWithKey:(NSString *)key; @end

#import "Organism.h" @implementation Organism - (id)initWithCoder:(NSCoder *)aDecoder { self = [super init]; if (self) { //code goes here } return self; } - (void)encodeWithCoder:(NSCoder *)aCoder { //code gose here }

So, using the class NSCoding, the class NSKeyedArchivier and the class NSKeyedUnarchivier, you can write and read objects into the iOS application sandbox.

Well, suppose that you have two classes with different properties. For example:

"Human" with name, surname, age;

#import <Foundation/Foundation.h> @interface Human : Organism @property (nonatomic, strong) NSString *name; @property (nonatomic, strong) NSString *surname; @property (nonatomic, strong) NSString *age; @end

"Cat" with name, pedigree.

#import <Foundation/Foundation.h> @interface Cat : Organism @property (nonatomic, strong) NSString *name; @property (nonatomic, strong) NSString *pedigree; @end

Human and Cat inherits from a third class named "Organism".

Without know if you are a Human or a Cat, you can encode and decode your classes, dynamically, using the Objective-c Runtime library, following the code below (Organism.m).

#import "Organism.h" #import <objc/message.h> //import the runtime library @implementation Organism - (id)initWithCoder:(NSCoder *)aDecoder { self = [super init]; if (self) { unsigned int pCounter = 0; objc_property_t *properties = class_copyPropertyList([self class], &pCounter); for (unsigned int i = 0; i < pCounter; i++) { objc_property_t prop = properties[i]; const char *propName = property_getName(prop); NSString *pUTF8 = [NSString stringWithUTF8String:propName]; [self setValue:[aDecoder decodeObjectForKey:pUTF8] forKey:pUTF8]; } free(properties); } return self; } - (void)encodeWithCoder:(NSCoder *)aCoder { unsigned int pCounter = 0; objc_property_t *properties = class_copyPropertyList([self class], &pCounter); for (unsigned int i = 0; i < pCounter; i++) { objc_property_t prop = properties[i]; const char *propName = property_getName(prop); NSString *pUTF8 = [NSString stringWithUTF8String:propName]; [aCoder encodeObject:[self valueForKey:pUTF8] forKey:pUTF8]; } free(properties); }

It will encode and decode your properties using their names. Amazing!!

So now you can read and write your encoded classes from and to the disk, using two custom methods (have you seen saveToDiskWithKey: and loadFromDiskWithKey: above??), into the Organism.m class:

#import "Organism.h" #import <objc/message.h> //import the runtime library @implementation Organism - (id)initWithCoder:(NSCoder *)aDecoder { self = [super init]; if (self) { unsigned int pCounter = 0; objc_property_t *properties = class_copyPropertyList([self class], &pCounter); for (unsigned int i = 0; i < pCounter; i++) { objc_property_t prop = properties[i]; const char *propName = property_getName(prop); NSString *pUTF8 = [NSString stringWithUTF8String:propName]; [self setValue:[aDecoder decodeObjectForKey:pUTF8] forKey:pUTF8]; } free(properties); } return self; } - (void)encodeWithCoder:(NSCoder *)aCoder { unsigned int pCounter = 0; objc_property_t *properties = class_copyPropertyList([self class], &pCounter); for (unsigned int i = 0; i < pCounter; i++) { objc_property_t prop = properties[i]; const char *propName = property_getName(prop); NSString *pUTF8 = [NSString stringWithUTF8String:propName]; [aCoder encodeObject:[self valueForKey:pUTF8] forKey:pUTF8]; } free(properties); } -(void)saveToDiskWithKey:(NSString *)key { NSData *data = [NSKeyedArchiver archivedDataWithRootObject:self]; [[NSUserDefaults standardUserDefaults] setObject:data forKey:key]; [[NSUserDefaults standardUserDefaults] synchronize]; } +(id)loadFromDiskWithKey:(NSString *)key { NSData *data = [[NSUserDefaults standardUserDefaults] objectForKey:key]; id result = [NSKeyedUnarchiver unarchiveObjectWithData:data]; return result; }

That's all!

You are ready to load and save Human and Cat:

Forget all the hard work swizzling stuff and making things conform to NSCoding, it’s not always easy anyway. You can simply call -initWithRootController: twice. That’s the spirit.

UIViewController *emptyVC = [[[UIViewController alloc] init] autorelease]; __block WANavigationController *navController = [[[WANavigationController alloc] initWithRootViewController:emptyVC] autorelease]; navController = [[((^ { NSKeyedUnarchiver *unarchiver = [[[NSKeyedUnarchiver alloc] initForReadingWithData:[NSKeyedArchiver archivedDataWithRootObject:navController]] autorelease]; [unarchiver setClass:[WANavigationBar class] forClassName:@"UINavigationBar"]; [unarchiver setClass:[UIViewController class] forClassName:NSStringFromClass([navController.topViewController class])]; return unarchiver; })()) decodeObjectForKey:@"root"] initWithRootViewController:navController.topViewController];