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SomewhereInIA-Cryptocache Mystery Cache

Difficulty:
5 out of 5
Terrain:
1 out of 5

Size: Size:   small (small)

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Geocache Description:

Indoor cache, great for mosquito season, and winter too.
Not at above location!
I recently moved here from, ND. This summer I created several difficult puzzles, thought I would transplant them here in IA. This one will probably be the most difficult.

This is in a mom&pop retail store, so it has limited hours of operation. Closed Sunday/Monday

Don't be a geocheater enabler
As a finder, you can use any means necassary (including cheating), but if you cheat, you have to identify the snitch!

This will be a lesson in cryptography, and an eye opener to people who just assume that internet transactions are secure. The real encryption used on the internet is far more advanced then this example, but it may demonstrate that the internet is not impossible to crack. By no means am I saying that it is not safe, but to some degree this is the basis of internet encryption.

An ammo can is at the following location:
FC 65 42 7B 4C 8B 83 6B 44 7A 55 9B E5 65 4F 78
4C 88 8B 6B 47 7C 5C 9B E6 2D 1F 3A 4C D8 D3 26
1E 2C 4C D2 C1 65 1F 27 1F D2 D6 20 56 07 09 D7
C1 2A 18 3A 42 9B 92 07 13 21 05 D5 D6 65 22 1F
4C CC DA 2C 15 21 4C D2 C1 65 19 27 4C CF DD 35
56 26 0A 9B E1 12 56 2F 1E DE D7 3F 13 3B -- --
Now you need a key to help you decode the above location.


If you had the key, here is a web page by jsignal that has a long and short version on how to decrypt the above location. http://jsignal.com/crypto
A one paragraph explaination of this process follows:
Binary XOR the ascii bits of the key with the encoded location, repeating the key as needed. For example if the key is 8 bytes long (say '12345678') and the encoded message is 23 bytes long (say 'ABCDEFGHIJKLMNOPQRSTUVW') you would have to XOR '123456781234567812345678123' with 'ABCDEFGHIJKLMNOPQRSTUVW'.

The real problem is, you don't have the key!
I will help you out by saying that it is 48 bits in length.

This is intended to be a super hard puzzle, you will have to write a program to solve it. Good luck, your going to need it!

The story of how I came up with this cache follows:
jsignal created a cache called 'GCH2MN-Cryptocache'. You had to go to one location to find the key, write it down, go home, then decode the location, where you would find an ammo can.
My problem was, both of these locations were about 60 miles away from where I live. So, instead of doing that, I spent about 8-12 hours writing a program to figure out the key and location.
Now I leave the same curse on you.
[Iowa Geocachers Logo]

Additional Hints (Decrypt)

Lbh unir gb svaq n jnl bs ryvzvangvat zrffntrf gung jurer abg qrpelcgrq jvgu gur pbeerpg xrl. Jung glcr bs punenpgref jbhyq gur zrffntr pbagnva? Ubj znal chapghngvba znexf jbhyq lbh rkcrpg gb svaq? Pna lbh guvax bs n frdhrapr bs punenpgref gung cebonoyl jbhyq or va gur zrffntr? Lbh arrq gb nhgbzngvpnyyl ryvzvangr onq qrpbqrf qbja gb n ernfbanoyr yvfg, znlor 1000, gura tb gueh vg ol unaq. Ol ybbxvat ng gur rapelcgrq zrffntr, vf gurer nalguvat lbh pna gryy nobhg pregnva ovgf bs gur 6 olgrf va gur xrl? Pbagvahr gb nfx lbhefrys zber dhrfgvbaf yvxr nobir.

Decryption Key

A|B|C|D|E|F|G|H|I|J|K|L|M
-------------------------
N|O|P|Q|R|S|T|U|V|W|X|Y|Z

(letter above equals below, and vice versa)