[Coco] Color Computer RSA

[Don Barber]

On 7/24/22 17:37, Fabian Rodriguez (CoCoByte) wrote:
>> I also implemented some filesytem/file-handling routines, and a 
>> screen output routine that will wrap text nicely. Hopefully by making 
>> all these open source, I can also help future CoCo programmers.
>
> This is very interesting. At what point did you decide is was worth it 
> to write your own and how long did this take ?

It probably took about 20 hours or so spread out of a few weeks. I 
couldn't find any similar subroutines/libraries out there so I had to 
write my own.

I did ask the list if there were any example subroutine libraries out 
there, and had two examples sent to me:
https://github.com/yggdrasilradio/delphiterm/blob/master/diskio.asm - 
this one is close but only handles files that can fit entirely in memory.
and the Dungeons of Daggorath disk patches William Astle had shared (but 
has since been taken offline, looks like the original copyright owner 
requested such) - this one hooked into the RSDOS rom and would 
write/read one byte at a time.

> I am thinking this could be useful to access online resources that 
> requires encryption... Or not ? In any case reading this makes me 
> think I too could tackle learning 6809 assembly language - great 
> inspiration :) Thank you!
>
RSA could be a start to TLS/SSL for the cert exchange stuff, but would 
also need a lot of other things like symmetric key exchange and cipher 
suite developed. And I don't see how it could be fast enough to happen 
within the timeout window needed before the connection is dropped.

I'd think slightly more useful than implementing TLS would be 
implementing HMAC. This would allow for signing cloud service requests, 
allowing for cloud storage or calling serverless functions.

> Cheers,
>
> F.
>
Thanks,

Don