AES vs RC4

#include <iostream>

#include <mach/mach_time.h>
#include <stdint.h>

#include <CommonCrypto/CommonCryptor.h>

struct Timer
{
	public:
	
		void start()
		{
			elapsed_ = 0;
			start_ = mach_absolute_time();
		}
		
		void stop()
		{
			end_ = mach_absolute_time();
		}
		
		double elapsed()
		{
			double elapsed = -1;
		
			uint64_t difference = end_ - start_;
			mach_timebase_info_data_t info;
			if (mach_timebase_info(&info) == 0) {
				elapsed = (double) difference * (double) info.numer / (double)info.denom;
			}
			
			return elapsed;
		}
		
	private:
	
		uint64_t start_;
		uint64_t end_;
		double elapsed_;
};

const size_t kDataLength = (4 * 1024 * 1024);

int test()
{
    char* data = new char[kDataLength];
    if (data != NULL)
    {
        char key[kCCKeySizeAES128] = {
            0xde, 0xad, 0xbe, 0xef,
            0xde, 0xad, 0xbe, 0xef,
            0xde, 0xad, 0xbe, 0xef,
            0xde, 0xad, 0xbe, 0xef
        };

        size_t dataOutMoved;

		Timer encryptionTimer;
		encryptionTimer.start();

        CCCryptorStatus status = CCCrypt(
            kCCEncrypt,
            kCCAlgorithmAES128,
            0,
            key,
            kCCKeySizeAES128,
            NULL,
            data,
            kDataLength,
            data,
            kDataLength,
            &dataOutMoved
        );

		encryptionTimer.stop();

        if (status != kCCSuccess) {
            std::cerr << "Encryption failed with error " << status << std::endl;
            return 1;
        }
		
		NSLog(@"Encryption took %f seconds (%.0f MB/second)",
			encryptionTimer.elapsed() / 1000000000.0, (4.0 / encryptionTimer.elapsed() * 1000000000.0));
		
		// Decrypt

		Timer decryptionTimer;
		decryptionTimer.start();		

		status = CCCrypt(
            kCCDecrypt,
            kCCAlgorithmAES128,
            0,
            key,
            kCCKeySizeAES128,
            NULL,
            data,
            kDataLength,
            data,
            kDataLength,
            &dataOutMoved
        );

		decryptionTimer.stop();

        if (status != kCCSuccess) {
            std::cerr << "Encryption failed with error " << status << std::endl;
            return 1;
        }
		
		NSLog(@"Decryption took %f seconds (%.0f MB/second)",
			decryptionTimer.elapsed() / 1000000000, (4.0 / decryptionTimer.elapsed() * 1000000000));
    }

    return 0;
}