How can I compute a SHA-2 (ideally SHA 256 or SHA 512) hash in iOS?

Question

The Security services API doesn\'t appear to allow me to compute a hash directly. There are plenty of public domain and liberally licensed versions available, but I\'d rathe

Answer 1

This is what worked for me

func sha256(securityString : String) -> String {
    let data = securityString.dataUsingEncoding(NSUTF8StringEncoding)!
    var hash = [UInt8](count: Int(CC_SHA256_DIGEST_LENGTH), repeatedValue: 0)
    CC_SHA256(data.bytes, CC_LONG(data.length), &hash)
    let output = NSMutableString(capacity: Int(CC_SHA1_DIGEST_LENGTH))
    for byte in hash {
        output.appendFormat("%02x", byte)
    }
    return output as String
}