Crypto Algorithm Question - Encryption and Decryption Method

Hey, i was wondering if someone could figure out the encryption and decryption method of below.

Upon submitting the text, you are generated a key and this changes the inputted text.

The key HCvvndyvyjditxixpefftoluvvrddllyiv makes the text "moo" = "18d8f09"

More examples below:

Key = HCxrwpwscoaefmnywdxkttmghxqucsgtqz
Text = moo
Output = 1-f4b9g

Key = HCsjijuabndwqdfjgrdfslndxnwpxdfrmu
Text = moo
Output = 15aW5V4


Key = HCjesgqfqvwlgcbolnoolpvltiaaurkjcd
Text = moo
Output = 1W3R05c

Key = HCacemhgwzoijqocuiubsxdqaajivnlsgz
Text = moo
Output = 1NUPYR0

Key = HCybaoethxfzziqhdfnxcpcojqglkpdqzf
Text = moo
Output = 1_gOXNW

Any help would be greatly appreciated.

What makes you think this is an encryption method? and why do you say it is a decryption method? Do you have any evidence it can actually decrypt the cipher text back into the clear text?

i.e. are you sure its not just a hash or maybe a HMAC?

I don't know if you can decrypt it, but i need to know what you guys think or if it's possible.
Anything you can come up with greatly helps, although i really only need the encryption method, if there is one.

Your examples don't show enough to make an intellegent guess.

Try using clear text strings of differing lengths, does that change the results? If so, it might be a cipher, if not, its probably a hash or HMAC

Make sure the string lengths are significantly different, if it is encryption and it uses padding two strings of approximate length may encrypt to the same size.e

For the key: HCbbqpfblynmmtejkgazicvorjdleeemdb
Input: string
Output: 1PLPM4Z25S0OP
Input: String
Output: 1NLPM4Z25S0OP
Input: string1
Output: 1PLPM4Z25S0OPVT
Input: 1
Output: 1LJ
Input: abcdefghi
Output: 1OJOK3020SROOYZ_b03
Input: ihgfedcba
Output: 1OROQ3422SROMYV_70V


For the key: HCywsqzgwwvhpxixurtlrvolqdlidshsld
Input: string
Output: 1a8-76136aiTU
Input: String
Output: 1-8-76136aiTU
Input: string1
Output: 1a8-76136aiTU64
Input: 1
Output: 186
Input: abcdefghi
Output: 1_6955231a_TT9-9_8_
Input: ihgfedcba
Output: 1_c9_5633a_TR969583

Also note that this information is found by logging packets, Thus the "Key" might not contain that starting "HC" that might just be a marker in the packets, same applies for the Output starting with "1" this may also be a marker. I'm trying to figure out how it works so i can login with my own client.

its hard to tell from the postings ( using proportional fonts etc) but it sure looks like all outputs are the same length.

This implied its a hash, as you'd expect a cipher to have different output for different inputs. (you really should try short and long strings (say 15 bytes and 50) to be sure.

And you have two examples where different inputs generate identical output. This can't be a cipher, unless the rules are to convert it to all upper case or all lower before doing any processing.

They are slightly different, look at the start of the hashes for them.
1PL != 1NL
and
1a8 != 1-8

Ill see if i can get more, but i don't know what the limits are on the length, i don't think i can go to large.
I tried to give a few similar examples and some varied length examples.

If i have a list of strings i can do them, and i can also slightly vary the key that it gets, say change the last character or something, could this be any usage to you?

ah you are right, I didn't catch that one character was different. I don't have the ascii chart memorized, but I'd bet that there is one character different in the input and one different in the output. (I know that S == s with on bit different)

That would mean its neither a hash or a cipher.
With any sort of good hash (MD5, SHA, etc.) changing one bit of the input should change many bits of the output.

I know the outputs will change for the same character with the same code, depending on if its at the same position in the input.

I post up some more inputs and outputs later, and i will also try slightly modifying the keys. I can also post the hex values of the characters.

Although i am now completely sure "HC" is not part of key it is simply a marker in the packets and "1" in the outputs is also only a marker.

it looks like a simple cipher. The length of the encryption changed with 'string' and 'string1'.

Note that although abcdefghi might seem like a simple sequence, if the cipher encodes the letters into numbers (which is much more common then leaving them) then it turns into a whole lot of increasing numbers. Similarly, 'string' is a whole lot of random numbers when you 'ascii'ise' it. Simpler strings to give it would be 'aaaa' or '0000' and single inputs such as ' '. Also give it the same input as the key, i.e use the key the itself as the input.

I'd say it is some sort of cipher, that possibly combines the key with each character of the input. It is very weak anyway.

As i now know for a fact HC and 1 are not part of the key they are only markers in the packets, i will no longer include them in the info. Will also post examples of forced/changed keys, hex of the input, output and key will also be posted.

Normal key: xysityfiktczfuotjdjhqapgiigtwphw (78 79 73 69 74 79 66 69 6B 74 63 7A 66 75 6F 74 6A 64 6A 68 71 61 70 67 69 69 67 74 77 70 68 77)
Input: !!!! (21 21 21 21)
Output: 657610RQ (36 35 37 36 31 30 52 51)






Forced keys: !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!! (21 21 21 21 21 21 21 21 21 21 21 21 21 21 21 21 21 21 21 21 21 21 21 21 21 21 21 21 21 21 21 21)
Input: !!!! (21 21 21 21)
Output: JIJIJIJI (4A 49 4A 49 4A 49 4A 49)

Input: """" (22 22 22 22)
Output: JJJJJJJJ (4A 4A 4A 4A 4A 4A 4A 4A)

Input: 0000 (30 30 30 30)
Output: KHKHKHKH (4B 48 4B 48 4B 48 4B 48)






And yet lets change every second character of the key and try the same passwords.

Forced keys: !"!"!"!"!"!"!"!"!"!"!"!"!"!"!"!" (21 22 21 22 21 22 21 22 21 22 21 22 21 22 21 22 21 22 21 22 21 22 21 22 21 22 21 22 21 22 21 22)
Input: !!!! (21 21 21 21)
Output: JIKJJIKJ (4A 49 4B 4A 4A 49 4B 4A)
(Note that one character of the input is worth 2 characters of output, and that depending on which part of the key get changed, effects the character that would be in the same position, if the strings where side by side).

Input: """" (22 22 22 22)
Output: JJKKJJKK (4A 4A 4B 4B 4A 4A 4B 4B)

Input: 0000 (30 30 30 30)
Output: KHLIKHLI (4B 48 4C 49 4B 48 4C 49)






Now lets try some different keys.

Forced key: P0ozP0ozP0ozP0ozP0ozP0ozzzzzzzzz (50 30 6F 7A 50 30 6F 7A 50 30 6F 7A 50 30 6F 7A 50 30 6F 7A 50 30 6F 7A 7A 7A 7A 7A 7A 7A 7A 7A)
Input: SSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSS (53 53 53 53 53 53 53 53 53 53 53 53 53 53 53 53 53 53 53 53 53 53 53 53 53 53 53 53 53 53 53 53)
Output: vt1Z0Y_9vt1Z0Y_9vt1Z0Y_9vt1Z0Y_9vt1Z0Y_9vt1Z0Y_9_9_9_9_9_9_9_9_9 (76 74 31 5A 30 59 5F 39 76 74 31 5A 30 59 5F 39 76 74 31 5A 30 59 5F 39 76 74 31 5A 30 59 5F 39 76 74 31 5A 30 59 5F 39 76 74 31 5A 30 59 5F 39 5F 39 5F 39 5F 39 5F 39 5F 39 5F 39 5F 39 5F 39)






Forced key: AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA (41 41 41 41 41 41 41 41 41 41 41 41 41 41 41 41 41 41 41 41 41 41 41 41 41 41 41 41 41 41 41 41)
Input: string (73 74 72 69 6E 67)
Output: ieifidhkhphi (69 65 69 66 69 64 68 6B 68 70 68 69)






Forced key: AZAAAxAAAAAAAAAAAAAAAAAAAAAAAAAA (41 5A 41 41 41 78 41 41 41 41 41 41 41 41 41 41 41 41 41 41 41 41 41 41 41 41 41 41 41 41 41 41)
Input: string (73 74 72 69 6E 67)
Output: ieHEidhkhp-_ (69 65 48 45 69 64 68 6B 68 70 2D 5F)

Input: AZAAAxAAAAAAAAAAAAAAAAAAAAAAAAAA (41 5A 41 41 41 78 41 41 41 41 41 41 41 41 41 41 41 41 41 41 41 41 41 41 41 41 41 41 41 41 41 41)
Output: fcFKfcfcfc_afcfcfcfcfcfcfcfcfcfcfcfcfcfcfcfcfcfcfcfcfcfcfcfcfcfc (66 63 46 4B 66 63 66 63 66 63 5F 61 66 63 66 63 66 63 66 63 66 63 66 63 66 63 66 63 66 63 66 63 66 63 66 63 66 63 66 63 66 63 66 63 66 63 66 63 66 63 66 63 66 63 66 63 66 63 66 63 66 63 66 63)

Hopefully this is more useful then previous posts, if you need anything else let me know.

Bump, sorry for the double post but i feel i provided the information you asked for.
If anything else is needed, ask.

Its almost been a month and i have no reply, can anyone look into it for me? Or is there anything else you need to help you find out how it works?

I feel i have given all info that was requested and nothing has happened with it.