AES128 category for NSData using CommonCrypto.

aes128_commoncrypt

// Marcin Krzyżanowski

#import <CommonCrypto/CommonCryptor.h>

@interface NSData (AES)
- (NSData *)AES128EncryptWithKey:(NSString *)key iv:(NSString *)iv;
@end

@implementation NSData (AES)

- (NSData *)AES128EncryptWithKey:(NSString *)key iv:(NSString *)iv
{
    int diff = kCCKeySizeAES128 - (self.length % kCCKeySizeAES128);

	NSMutableData *adjustedData = [NSMutableData dataWithData:self];
	[adjustedData appendData:[[NSMutableData alloc] initWithLength:diff]];
	
    size_t bufferSize = adjustedData.length + kCCBlockSizeAES128;
    void *buffer = malloc(bufferSize);

    size_t numBytesEncrypted = 0;
    CCCryptorStatus cryptStatus = CCCrypt(kCCEncrypt, kCCAlgorithmAES128,
										   0x00, //No padding
                                          [key UTF8String], kCCKeySizeAES128,
                                          [iv UTF8String],
                                          adjustedData.bytes,
                                          adjustedData.length,
                                          buffer,
                                          bufferSize,
                                          &numBytesEncrypted);

    if(cryptStatus == kCCSuccess) {
        return [NSData dataWithBytesNoCopy:buffer length:numBytesEncrypted];
    }
    return nil;
}

@end