Image Encryption in Swift

Question

I am using IDZSwiftCommonCrypto for image encryption using StreamCryptor described as an example at its GitHub page: https://github.com/iosdevzone/IDZSwiftCommo

Answer 1

xx.append(outputBuffer, count: cryptedBytes)

should help.

below is sample code for picking up an encrypted image file and returning the data.

func decryptImage(from path:URL)-> Data? {
    var decryptData = Data()

    let sc = StreamCryptor(operation:.decrypt, algorithm:.aes, options:.PKCS7Padding, key:key, iv:iv)

    guard let encryptedInputStream = InputStream(fileAtPath: path.relativePath) else {
        return nil
    }

    var inputBuffer = [UInt8](repeating: 0, count: Int(1024))
    var outputBuffer = [UInt8](repeating: 0, count: Int(1024))

    encryptedInputStream.open()

    var cryptedBytes : Int = 0
    while encryptedInputStream.hasBytesAvailable
    {
        let bytesRead = encryptedInputStream.read(&inputBuffer, maxLength: inputBuffer.count)

        let status = sc.update(bufferIn: inputBuffer, byteCountIn: bytesRead, bufferOut: &outputBuffer, byteCapacityOut: outputBuffer.count, byteCountOut: &cryptedBytes)

        if (status != Status.success) {
        encryptedInputStream.close()
            return nil
        }

        if(cryptedBytes > 0)
        {
            decryptData.append(outputBuffer, count: cryptedBytes)
        }
    }

    let status = sc.final(bufferOut: &outputBuffer, byteCapacityOut: outputBuffer.count, byteCountOut: &cryptedBytes)
    if (status != Status.success) {
        encryptedInputStream.close()
        return nil
    }

    if(cryptedBytes > 0)
    {
        decryptData.append(outputBuffer, count: cryptedBytes)
    }
    encryptedInputStream.close()
    return decryptData
}

Happy coding :)