could you crack this please

[unhappy]

he's comparing a character from string[n]

[Relyt]

ark_templar

Tim_axe made some very important points and if I may add to them a bit...

Encryption can be deciphered given enough time. The secret to keeping your secrets secret longer, lies within two processes. First you must have a very strong tested and tried algorithm. However don't be fooled into believing that the algorithm is the most important part because that is simply not true. And the second part, the most important, is keeping the "Key" secret and changing it frequently.

Does this mean it can't be cracked? No. However make the guy pull his hair out trying and by the time he may have figure part of it out, you've changed the key on him or the secret no longer requires safeguarding.

Here's a tutorial with more info:

http://www.antionline.com/tutorials/jump.php?493

Additionally here's a link the encryption tutorials:

http://www.antionline.com/tutorials/?c=89

cheers

[;TT]

Originally posted here by poohsuntzu
Careful!



That is a windows only usage of C!!!! Meaning that pause is only going to register on windows machines. Shame shame shame!

Ok, I don't ****ing get this? What does this have to do with ANYTHING?! He posted an example of how ot use the VB tags ["code"] and then your comment for some reason is flaming green for an inane comment that has 0 to do with the discussion at hand... wtf is going on?

[Donkey Punch]

Ok, I don't ****ing get this? What does this have to do with ANYTHING?! He posted an example of how ot use the VB tags ["code"] and then your comment for some reason is flaming green for an inane comment that has 0 to do with the discussion at hand... wtf is going on?

Perhaps he was pointing to portability, but that was not the point in the orginal post. It makes no difference. The legacy of AntiOnline continues and will not change. Get over it.

[skiddieleet]

[poohsuntzu]

I'm sorry, did the cranky-old-men have a problem with me mentioning portability problems I found in code he asked us to review and posted? And yes he did ask us to take a look at it.

also im putting my prog below so if you could play devils advocate with it
(and sorry but posting ruined my indentation)

Come on, I dare you to tell me I'm off topic when you won't even read the parent post.

[unhappy]

if you want your code to be portable you can use "getchar()" fuction to pause the execution untill the user presses a key

just my 2 cents

[ark_templar]

people thankyou for responding the responses have been helpfull esp. Reylt and tim_axe
thankyou for the links as well
hope you guys dont mind if i create a new post soon with a new (and hopefully improved) algorithm (I'll be bak ).
well thanx all and i'm sorry that you guys started flaming eachother on my page but end it now once again
hastalavista but I'll be bak ;-)

[Linen0ise]

Buffer Overflow:

printf("\ntask completed sucessfully\n");
--->scanf("%d",&for_pause);
....
}


It will keep looping until a number is entered. Imagine alot of characters or "hex" numbers were entered

[0x7e]

i hope you all will forgive the slightly pedantic interjection of an outsider, but ark_templar brings up an interesting point about arbitrary transformations when he asks, "could you explain the concept of an encryption key whats its aim if the algo of encryption is unknown then I think (thats what I wanted to test) that the thing is pretty much unbreakable." this is a topic in "nonlinear algebra" which interests me.

in a sense, encryption is just an arbitrary mapping from a string of data (a vector) to another string of data. decryption is accomplished by guessing an inverse mapping which maps the encrypted data back to the original data. it does not require one to know exactly what algorithm was used to encrypt the data in the first place. in fact most reasonably simple keyless algorithms have the same inverse mapping, up to a variation in a couple of parameters. a good encryption algorithm has very few inverse algorithms regardless of the simplicity of the encryption itself. this is the purpose of the key. the key is an arbitrary set of steps in your encryption whose sole purpose is to reduce the number of inverses to your encryption. modifying a keyless encryption algorithm is, at best, equivalent to changing a couple of bits of the key of a keyed algorithm, and thus we can much more efficiently increase the difficulty of cracking our encrypted message by incorporating arbitrary, randomly generated keys into our algorithm than by trying to write more or different steps into it.

and tim axe, i may be mistaken, but i think that while the allies cracked the nazis' encryption due partly to stealing the machines off of sinking submarines, the allies codes remained intact through the end of the war. the fact that the wind-talkers code remained tight through the war is more a testament to human bigotry than mathematical brilliance, methinks. the polish resistance under nazi occupations used, as radio call signs, surnames such as brzeszczesciekiewiec (sp?) to assure themselves that they could not be infiltrated by nazi trojans, and to great avail. never underestimate a brilliant mind's unwillingness to extend his intellectual powers outside his own cultural bounds. to that end, a great read for ark_templar would be stephenson's cryptonomicon, which covers in great detail the world war two history of cryptography and its mathematics, be it only a novel.

and on a more extraneous note, does anybody know how to set up encrypted swap partitions on a linux box? i figure it's kind of silly to encrypt a filesystem if the key is going to sit in memory and then perhaps be written to the swap partition, whose persistence is god knows how long.

forgive the length of my wind.