ObjFW  Diff

 * file.
 */

#import "OFData.h"

OF_ASSUME_NONNULL_BEGIN

/*!
 * @class OFSecureData OFSecureData.h ObjFW/OFSecureData.h
 *
 * @brief A class for storing arbitrary data in secure (non-swappable) memory,
 *	  securely wiping it when it gets deallocated.
 *
 * @warning Non-swappable memory might be unavailable, in which case this falls
 *	    back to swappable memory, but still wipes the data when it gets
 *	    deallocated. Check the @ref allowsSwappableMemory property to see
 *	    whether a particular OFSecureData might be allocated in swappable
 *	    memory.
 */
OF_SUBCLASSING_RESTRICTED
@interface OFSecureData: OFData
{
	struct page *_page;
	bool _allowsSwappableMemory;
}

/*!
 * @brief Whether the data may be stored in swappable memory.
 */
@property (readonly, nonatomic) bool allowsSwappableMemory;

/*!
 * @brief All items of the OFSecureData as a C array.
 *
 * Modifying the returned array directly is allowed and will change the contents
 * of the data.
 */
@property (readonly, nonatomic) void *mutableItems OF_RETURNS_INNER_POINTER;

/*!
 * @brief Preallocates the specified number of bytes for unswappable memory.
 *
 * This is useful to allocate unswappable memory before enabling a sandbox that
 * does not allow it anymore.
 *
 * @note This may only be called once per thread!
 * @note Preallocated unswappable memory is only available for data that is
 *	 smaller than a single page!
 *
 * @param size The number of bytes of unswappable memory to preallocate
 */
+ (void)preallocateUnswappableMemoryWithSize: (size_t)size;

/*!
 * @brief Creates a new, autoreleased OFSecureData with count items of item
 *	  size 1, all set to zero.
 *
 * @param count The number of zero items the OFSecureData should contain
 * @param allowsSwappableMemory Whether the data may be stored in swappable
 *				memory
 * @return A new, autoreleased OFSecureData
 */
+ (instancetype)dataWithCount: (size_t)count
	allowsSwappableMemory: (bool)allowsSwappableMemory;

/*!
 * @brief Creates a new, autoreleased OFSecureData with count items of the
 *	  specified item size, all set to zero.
 *
 * @param itemSize The size of a single item in the OFSecureData in bytes
 * @param count The number of zero items the OFSecureData should contain
 * @param allowsSwappableMemory Whether the data may be stored in swappable
 *			       memory

#ifdef OF_HAVE_FILES
+ (instancetype)dataWithContentsOfFile: (OFString *)path OF_UNAVAILABLE;
#endif
+ (instancetype)dataWithContentsOfURL: (OFURL *)URL OF_UNAVAILABLE;
+ (instancetype)dataWithStringRepresentation: (OFString *)string OF_UNAVAILABLE;
+ (instancetype)dataWithBase64EncodedString: (OFString *)string OF_UNAVAILABLE;

/*!
 * @brief Initializes an already allocated OFSecureData with count items of
 *	  item size 1, all set to zero.
 *
 * @param count The number of zero items the OFSecureData should contain
 * @param allowsSwappableMemory Whether the data may be stored in swappable
 *				memory
 * @return An initialized OFSecureData
 */
- (instancetype)initWithCount: (size_t)count
	allowsSwappableMemory: (bool)allowsSwappableMemory;

/*!
 * @brief Initializes an already allocated OFSecureData with count items of the
 *	  specified item size, all set to zero.
 *
 * @param itemSize The size of a single item in the OFSecureData in bytes
 * @param count The number of zero items the OFSecureData should contain
 * @param allowsSwappableMemory Whether the data may be stored in swappable
 *				memory

- (instancetype)initWithContentsOfFile: (OFString *)path OF_UNAVAILABLE;
#endif
- (instancetype)initWithContentsOfURL: (OFURL *)URL OF_UNAVAILABLE;
- (instancetype)initWithStringRepresentation: (OFString *)string OF_UNAVAILABLE;
- (instancetype)initWithBase64EncodedString: (OFString *)string OF_UNAVAILABLE;
- (instancetype)initWithSerialization: (OFXMLElement *)element OF_UNAVAILABLE;

/*!
 * @brief Returns a specific item of the OFSecureData.
 *
 * Modifying the returned item directly is allowed and will change the contents
 * of the data array.
 *
 * @param index The number of the item to return
 * @return The specified item of the OFSecureData
 */
- (void *)mutableItemAtIndex: (size_t)index OF_RETURNS_INNER_POINTER;

/*!
 * @brief Checks the OFSecureData for equality to another object.
 *
 * If the specified object is a subclass of @ref OFData, the comparison is
 * performed in constant time.
 *
 * @param object The object which should be tested for equality
 * @return A boolean whether the OFSecureData is equal to the specified object
 */
- (bool)isEqual: (nullable id)object;

/*!
 * @brief Zeroes the data.
 */
- (void)zero;

- (OFString *)stringRepresentation OF_UNAVAILABLE;
- (OFString *)stringByBase64Encoding OF_UNAVAILABLE;
#ifdef OF_HAVE_FILES