DataEncryptor is a lightweight utility for compressing and encrypting an arbitrary payload. It employs gzip compression and AES data encryption to a piece of data using a randomly-generated and RSA asymmetrically-encrypted key.
DataEncryptor *encryptor = [[DataEncryptor alloc] initWithX509URL:[[NSBundle mainBundle] URLForResource:@"my_public_key.der" withExtension:nil]];
NSData *compressedData = [encryptor compressData:plaintextData];
NSData *encryptedData = [encryptor encryptData:compressedData];
NSString *encryptedSymmetricKey = [encryptor.encryptedSymmetricKey base64EncodedStringWithOptions:0L];See notes atop DataEncryptor.m for key setup and decryption steps.
Decryption and decompression is achievable using standard Mac OS system tools, but DataEncryptor does not provide related API. This would be an obvious improvement.