Here's another....file I/O difficulties.

[red_Marvin]

It could be a quote from a book that both parties have, and then only
have a reference as "page 57" etc. But it might be good to combine
more than one letter to make the key char so you get the whole 0 to 255
range of key character possibillities.

Also: you would perhaps want to jumble up the text in some way, so
it appears to be random chars, and not words.

Aw heck, it seems easier to just give the reciever a floppy with a normal
key on :-? :wink:

[stylin]

What's a floppy?

[Moneo]

.....
I wonder how easy it is to crack XOR encryption. I used to send my encrypted files to a buddy of mine and he'd always be able to crack them.

Why don't you send your friend a copy of a file encrypted by the enhanced Winer algorithm? Let's see if he can crack it. My guess is that you could probably give him the encryption password, and lacking the algorithm, he still wouldn't derive the unencrypted text.

I just remembered an old encryption trick that I used back in the 1970's. I had one or more dummy characters within the password, for the remote possibility that someone got a hold of the password. The algorithm knew which character(s) were dummy and just ignored them, both for encryption and decryption obviously. Easy to implement and could cause a hacker lots of headaches. I used this for a banking communications application and never had a problem.
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[na_th_an]

What's a floppy?

This strange thing. I never seen one. It must be some kind of alien technollogy, or made by the commies to take over the world, or something.

I think it's explosive.

[stylin]

Definitely looks like a communist device to me. You mean it matters what direction I insert this "floppy"?

[na_th_an]

It does. Notice the little arrow at the top left side.

But it may be a trap. Beware.

[Zack]

.....
I wonder how easy it is to crack XOR encryption. I used to send my encrypted files to a buddy of mine and he'd always be able to crack them.

Why don't you send your friend a copy of a file encrypted by the enhanced Winer algorithm? Let's see if he can crack it. My guess is that you could probably give him the encryption password, and lacking the algorithm, he still wouldn't derive the unencrypted text.

I just remembered an old encryption trick that I used back in the 1970's. I had one or more dummy characters within the password, for the remote possibility that someone got a hold of the password. The algorithm knew which character(s) were dummy and just ignored them, both for encryption and decryption obviously. Easy to implement and could cause a hacker lots of headaches. I used this for a banking communications application and never had a problem.
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I would, but the guy I used to send it to is really busy - actually, you probably know him, he hangs around here. I knew him as Neo, but me may have changed his name.
But how does one go about cracking a regulare one-character XOR cipher? I suppose it's a bit like doing "Cryptograms", but what about executable files? It's gotta be a nightmare cracking those.

[Moneo]

......I would, but the guy I used to send it to is really busy - actually, you probably know him, he hangs around here. I knew him as Neo, but me may have changed his name.
But how does one go about cracking a regulare one-character XOR cipher? I suppose it's a bit like doing "Cryptograms", but what about executable files? It's gotta be a nightmare cracking those.

Neo hasn't posted here since the end of November 2005.

I don't know what you mean by "a regular one-character XOR cipher". Actually, I have never spent any time at all trying to crack any encryption algorithms.

I have only had to implement encryption 2 or 3 times in 44 years of experience. I used encryption packages, like DES and Public Key, a few other times.

Encryption algorithms are like sort algorithms. You can spend tons of time fooling around with them, but in reality you will find very limited usage for them in applications that you get paid for.
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