Support Apple specific messages 9, 10, 16

[thezealousfool]

This PR adds support for the following messages:

• 9: Apple's variant of continuous updates
• 10: Setting some kind of mode. Ignores the message
• 16: Encrypted keyboard and mouse event messages.

This PR does not add full support of Apple's VNC client as the image does not look right but the keyboard and mouse events are transferred correctly so wanted to create a PR with the limited subset.

[any1]

Nice! Figuring this out can't have been trivial. Thanks for putting in the effort!

It's unfortunate that they've chosen to reuse the AES-ECB cipher from the authentication phase. It's fine for a single message, but reuse is bad. See https://en.wikipedia.org/wiki/Block_cipher_mode_of_operation#ECB-weakness

I wonder if there is a way to tell it to switch to a cipher that isn't completely broken.

This PR does not add full support of Apple's VNC client as the image does not look right [...]

I'm curious. What does the image look like?

[Neustradamus]

@thezealousfool: Interesting PR!