QL Cryptography

Anything QL Software or Programming Related.
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stevepoole
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QL Cryptography

Post by stevepoole »

Hi Folks,

It can be considerable fun and amusement trying to write cryptographic programs for the QL :

But as not many people seem to communicate on 'QL platform' hardware, do we really need them ?

On PCs you can use secure links with built-in encryption, and many QL people do indeed use emulators.

The QL scene is very much an open source affaire, so again, do we really need encryption ?

On this forum, (which is https), we can communicate via PMs anyway....

What do you all think ?

Steve.
_______________


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vanpeebles
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Re: QL Cryptography

Post by vanpeebles »

I put some cryptograph easter eggs in my QL adventure game :D


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bwinkel67
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Re: QL Cryptography

Post by bwinkel67 »

Back in the early 90's when my QL was the only computer that I owned and I used microdrives, I wrote a small stream cipher that encrypted some of my work. It could only do data (i.e. no executables).
Crypt.zip
(4.36 KiB) Downloaded 66 times
Source code included...it's very simple but decently secure. I was looking at the random number geneartor I used and have no idea where I got it from. Plus my password hash has a flaw as it only ranges 15 bits (max positive 16 bit value) and even though otherwise it's 32 bits, that hash genrating a key reduces it to 15 bits...sigh...just wasn't thinking back then how the key impacted the cipher. To fix it just make RAND_MAX 31 bits (i.e. the max positive 32 bit number) and recompile (Digital C SE).

Note there are a few other encryption programs on Dilwyn's site.


swensont
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Re: QL Cryptography

Post by swensont »

I think it was Jonathan Hudson that ported over Pretty Good Privacy (PGP) to the QL. There was a time when PGP was considered a munition and had export controls. I'm sure there is now better levels of encryption, but for the QL, PGP is about as good as it gets.

Tim


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bwinkel67
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Re: QL Cryptography

Post by bwinkel67 »

Oh wow, didn't know PGP was running on the QL. Does it need extra RAM and acceleration to work? PGP used to use a block cipher comparable to DES (I have been toying with implementing DES on a QL since it's a fairly simple algorithm).


swensont
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Re: QL Cryptography

Post by swensont »

I think PGP probably needs extra memory. I ran it a few times many years ago. Pretty sure I had a Gold Card then. Jonathan was good at porting a number of Unix tools to the QL (and so did a few others). Probably the most impressive is Perl 4.

Tim


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