(Objective-c) How to get MD5 hash string of a NSData

- (NSString*)dataMD5:(NSData*)data {
CC_MD5_CTX md5;

CC_MD5_Init(&md5);

CC_MD5_Update(&md5, [data bytes], [data length]);

unsigned char digest[CC_MD5_DIGEST_LENGTH];
CC_MD5_Final(digest, &md5);
NSString* s = [NSString stringWithFormat: 

@"%02x%02x%02x%02x%02x%02x%02x%02x%02x%02x%02x%02x%02x%02x%02x%02x",
digest[0], digest[1],
digest[2], digest[3],
digest[4], digest[5],
digest[6], digest[7],
digest[8], digest[9],
digest[10], digest[11],
digest[12], digest[13],
digest[14], digest[15]];
return [s uppercaseString];
}