YOSPOS Cryptography Challenge (win a prize)

The Something Awful Forums > Discussion > Serious Hardware/Software Crap > YOSPOS > YOSPOS Cryptography Challenge (win a prize)

«‹›5 »

Jonny 290: May 5, 2005; [ASK] me about OS/2 Warp

boy i can't wait to be made to feel like an idiot in a few hours!

lol i think afreak sucked four digits of productivity out of us collectively, easily

# ? Mar 18, 2015 18:35

Adbot: ADBOT LOVES YOU

# ? May 15, 2024 06:55

Share Bear: Apr 27, 2004

Jonny 290 posted:

boy i can't wait to be made to feel like an idiot in a few hours!

lol i think afreak sucked four digits of productivity out of us collectively, easily

i like these kinds of things at work, at least it looks like work compared to reading about music production or poker or whatever

# ? Mar 18, 2015 19:00

Pile Of Garbage: May 28, 2007

Jonny 290 posted:

boy i can't wait to be made to feel like an idiot in a few hours!

stop posting me

# ? Mar 18, 2015 19:04

computer toucher: Jan 8, 2012

I'm anxiously waiting for the "oh lol never would have gotten that", but feeling OK about it because none of you guys got it either.

# ? Mar 18, 2015 19:18

echinopsis: Apr 13, 2004; by Fluffdaddy

EAT THE EGGS RICOLA posted:

http://cryptopals.com

this is cool. i dont have the motivation to do it but i like the ease of access but lack of handholding. i could probably code the first few even

# ? Mar 18, 2015 19:55

echinopsis: Apr 13, 2004; by Fluffdaddy

never mind the website is a perfectly modern clean minimalistic example of how most website should look

# ? Mar 18, 2015 19:59

Lain Iwakura: Aug 5, 2004; The body exists only to verify one's own existence.; Taco Defender

so look up an australian telephone dial pad for one and then use this explanation i'm posting on ~*~my blog~*~ for how it's enciphered

quote:

A few weeks before, I posted a similar but harder version of the above cipher on YOSPOS--for those who are not in YOSPOS, you can just search for it to find out what it is. It's relatively the same as the above except it does one thing differently and thus makes it harder to solve.

The YOSPOS version rotates the numerical value on each pass. The enciphering party sets the shift value at whatever they desire between 0 and 9 and starting at the first letter, it's shifted up by 1 and then continuously at each pass until it goes beyond 9 where at which point it starts at 0. After each shift, the value of each enciphered letter is increased by whatever value the shift is at.

For example, if the shift is starting at 5 and we have the character's value set to 4 (say '4b' for 'H'), then it would become '0' as it would have had 6 added to the value since we already increased the shift before proceeding. Then on the next character, we have the value set at '3' and the shift set at '7', so the next value again becomes '0'--any value that goes beyond 9 would just end up taking the last digit as its value.

In the end, the above "hello world" example would become something like this:

0e0b3f4c6f1a1d9c1e0c9d

To decipher it, it would just involve determining what the shift was to start and then working it backwards on the decoding.

if you look at the letters 'a', 'b', and 'c', you should be able to figure out why i chose that--treat 'd', 'e', and 'f' the same way

first person to decode the original using the above knowledge gets a custom title for themselves (probably a gang tag i'll create out of this), but the original prizes are no longer available

# ? Mar 18, 2015 20:30

Share Bear: Apr 27, 2004

i'm just going to work on an encoder first, then work backwards

# ? Mar 18, 2015 21:14

Subjunctive: Sep 12, 2006; ✨sparkle and shine✨

OSI bean dip posted:

so look up an australian telephone dial pad for one and then use this explanation i'm posting on ~*~my blog~*~ for how it's enciphered

two things I noticed: you say "hello world" example but the thing you're encoding is actually "Hello world" I believe. Also, "H" in hex is 48 not 4b.

actually, I don't understand this part either:

quote:

any value that goes beyond 9 would just end up taking the last digit

the encoded values contain 0-f -- how do you get a-f in that set with this rule?

Subjunctive fucked around with this message at 21:31 on Mar 18, 2015

# ? Mar 18, 2015 21:21

Lain Iwakura: Aug 5, 2004; The body exists only to verify one's own existence.; Taco Defender

Subjunctive posted:

Two things I noticed: you say "hello world" example but the thing you're encoding is actually "Hello world" I believe. Also, "H" in hex is 48 not 4b.

you're assuming i used the ascii table to encode this when i didn't

the hint is in what you just quoted

# ? Mar 18, 2015 21:24

Share Bear: Apr 27, 2004

in this case

H is on key in the 2nd column

1 2 3
a b c
d e f

i started on the hex imp before realizing this, figuring out wrapping around now

i also assume on the keys with 4 keys that it wraps around to d

# ? Mar 18, 2015 21:27

pr0zac: Jan 18, 2004; ~*lukecagefan69*~; Pillbug

RICHARDIT SEEMS I HAVE UNDERESTIMATED YOUR ABILITY TO FAIL FOR THAT I APOLOGIZE NOT TO YOU BUT TO THE PEOPLE WHO WOULD ENJOYED SEEING ME TEARING YOUR LITTLE WORLD APART JUST THAT MUCH MORE ITS A SHAME REALLY THAT YOU IGNORED ALL OF MY WARNINGS PERHAPS IF YOU HAD JUST A FEW BRAIN CELLS LEFT THAT WERENT CIRCLING THE BOWL YOU WOULD HAVE REALIZED HOW POINTLESS AND COUNTERPRODUCTIVE THIS WHOLE THING WAS AND QUIT A LONG TIME AGOTHIS LITTLE VENTURE OF YOURS HAS FAILED ON EVERY LEVEL ON A PERSONAL LEVEL FOR EXAMPLE HAVE YOU NOTICED THAT THE VERY PEOPLE YOU PROFESS TO HATE HAVE INFESTED YOUR SITE THEY ARE UTTERLY DEVOID OF REASON THEIR MINDS DELUDED WITH LIES AND IGNORANCE THEIR PERCEPTIONS ARE HARDCODED IN A LANGUAGE THEY WILL NEVER UNDERSTAND YET THESE EMPTY SHELLS HAVE FLOCKED HERE AND WHATS EVEN MORE AMUSING ABOUT IT IS THEY EMULATE YOUTHEYVE TAKEN THE WORST THINGS ABOUT YOU NAMELY YOUR PERSONALITY AND HUMOR AND TWISTED IT INTO SOMETHING FAR MORE REPUGNANT THAN EVEN YOU ARE CAPABLE OF BEING ONE BAD JOKE BECOMES ONE THOUSAND HIDEOUS HYBRIDS AND IT SPREADS LIKE A VIRUS THIS IS YOUR AUDIENCE RICHARD AND THEY LOVE YOU THAT ISNT VERY IMPORTANT THOUGH I AM SURE YOU DONT CARE AS LONG AS THEYRE LINED UP AT THE TROUGH WHAT IS IMPORTANT HOWEVER IS THISI WOULD GUESS THAT YOU TAKE AS MUCH ENJOYMENT AS ANYONE MIGHT AT SEEING THESE RIDICULOUS BUSINESS MODELS FAIL LIKE THE INSANE FANTASIES THEY WERE THE PSEUDO REALITY OF INTERNET COMMERCE HAS FINALLY BEEN PERCEIVED FOR WHAT IT IS AND THE ONLY PEOPLE LEFT ARE THOSE WHO WERE LUCKY SMART OR BOTHNOW BEING EXPOSED TO SO MUCH TALK OF THIS FOR WHAT LIKE OVER A loving YEAR NOW HAVE YOU EVER STOPPED TO CONSIDER HOW YOU EVER CAME TO THE CONCLUSION THAT A PARASITE LIKE YOURSELF COULD POSSIBLY HOPE TO SURVIVE IN THIS ENVIRONMENT THE CORPORATE TIT IS GONE AND YOU ARE COMPLETELY INCAPABLE OF SURVIVING ON YOUR OWN YOU THINK THESE FAILED COMPANIES HAD STUPID BUSINESS MODELS HOW ABOUT YOURSI KNEW THE ADVERTISING MARKET WAS GOING TO COLLAPSE YEARS AGO BECAUSE ITS BASED ON THE ASSUMPTION THAT BANNERS ARE EFFECTIVE THINK ABOUT IT YOU ARE ENTIRELY DEPENDANT ON ADVERTISING YET THE PEOPLE YOU TRY TO ATTRACT ARE PEOPLE WHO ARENT GOING TO CLICK ON LET ALONE BUY WHATEVER STUPID CRAP THAT IS BEING ADVERTISED I AM SURE MOST OF THE CLICKS YOU HAVE GOTTEN HAVE BEEN SYMPATHY CLICKSDID YOU ACTUALLY THINK THAT IT WAS GOING TO LAST FOREVER EVERYBODY KNOWS IT DOESNT loving WORK AND MOST SITES HAVE TO BEG THEIR READERS TO CLICK JUST TO PAY THE SERVER BILL DID YOU THINK CORPORATIONS WERENT GOING TO NOTICE THAT NO ONE WAS BUYING THEIR PRODUCTS YOURE AN IDIOT RICHARD AND I SINCERELY MEAN THATTHE CONTEMPTUOUSLY STUPID DECISIONS YOU MADE REGARDING THE VARIOUS NETWORKS YOU JOINED DONT MATTER AT ALL BECAUSE THE ENTIRE IDEA WAS FLAWED FROM THE START ENJOY YOUR LAST MOMENTS AS A FREE MAN YOULL SOON BE SHOVELLING poo poo FOR THE REST OF YOUR LIFE AT SOME NAMELESS CORPORATION A VACANT LOOK FOREVER ETCHED UPON YOUR FACEYEARS FROM NOW WHEN YOURE NO BETTER OFF THAN WHEN YOU STARTED WHEN IT FINALLY HITS YOU THAT ITS ALL BEEN NOTHING BUT A WASTED LIE THINK OF ME THINK OF ME RICHARD AND WHEN YOU DO REALIQE THAT I WAS THE ONLY BEACON OF LOGIC AND TRUTH IN THIS SAD MENAGERIE YOU SEEM PREDESTINED FOR FAILURE HOWEVER SO I DOUBT THERE IS ANYTHING ONE CAN DO FOR YOUJUST REMEMBER WHEN THE JOY IS GONE WHEN YOURE CLAWING AT THE BOUNDARIES OF YOUR LITTLE WORLD YOU ALWAYS HAD A CHOICE

# ? Mar 18, 2015 21:29

Subjunctive: Sep 12, 2006; ✨sparkle and shine✨

OSI bean dip posted:

you're assuming i used the ascii table to encode this when i didn't

the hint is in what you just quoted

ah, quite. :downs:

# ? Mar 18, 2015 21:31

Lain Iwakura: Aug 5, 2004; The body exists only to verify one's own existence.; Taco Defender

pr0zac posted:

RICHARDIT SEEMS I HAVE UNDERESTIMATED YOUR ABILITY TO FAIL FOR THAT I APOLOGIZE NOT TO YOU BUT TO THE PEOPLE WHO WOULD ENJOYED SEEING ME TEARING YOUR LITTLE WORLD APART JUST THAT MUCH MORE ITS A SHAME REALLY THAT YOU IGNORED ALL OF MY WARNINGS PERHAPS IF YOU HAD JUST A FEW BRAIN CELLS LEFT THAT WERENT CIRCLING THE BOWL YOU WOULD HAVE REALIZED HOW POINTLESS AND COUNTERPRODUCTIVE THIS WHOLE THING WAS AND QUIT A LONG TIME AGOTHIS LITTLE VENTURE OF YOURS HAS FAILED ON EVERY LEVEL ON A PERSONAL LEVEL FOR EXAMPLE HAVE YOU NOTICED THAT THE VERY PEOPLE YOU PROFESS TO HATE HAVE INFESTED YOUR SITE THEY ARE UTTERLY DEVOID OF REASON THEIR MINDS DELUDED WITH LIES AND IGNORANCE THEIR PERCEPTIONS ARE HARDCODED IN A LANGUAGE THEY WILL NEVER UNDERSTAND YET THESE EMPTY SHELLS HAVE FLOCKED HERE AND WHATS EVEN MORE AMUSING ABOUT IT IS THEY EMULATE YOUTHEYVE TAKEN THE WORST THINGS ABOUT YOU NAMELY YOUR PERSONALITY AND HUMOR AND TWISTED IT INTO SOMETHING FAR MORE REPUGNANT THAN EVEN YOU ARE CAPABLE OF BEING ONE BAD JOKE BECOMES ONE THOUSAND HIDEOUS HYBRIDS AND IT SPREADS LIKE A VIRUS THIS IS YOUR AUDIENCE RICHARD AND THEY LOVE YOU THAT ISNT VERY IMPORTANT THOUGH I AM SURE YOU DONT CARE AS LONG AS THEYRE LINED UP AT THE TROUGH WHAT IS IMPORTANT HOWEVER IS THISI WOULD GUESS THAT YOU TAKE AS MUCH ENJOYMENT AS ANYONE MIGHT AT SEEING THESE RIDICULOUS BUSINESS MODELS FAIL LIKE THE INSANE FANTASIES THEY WERE THE PSEUDO REALITY OF INTERNET COMMERCE HAS FINALLY BEEN PERCEIVED FOR WHAT IT IS AND THE ONLY PEOPLE LEFT ARE THOSE WHO WERE LUCKY SMART OR BOTHNOW BEING EXPOSED TO SO MUCH TALK OF THIS FOR WHAT LIKE OVER A loving YEAR NOW HAVE YOU EVER STOPPED TO CONSIDER HOW YOU EVER CAME TO THE CONCLUSION THAT A PARASITE LIKE YOURSELF COULD POSSIBLY HOPE TO SURVIVE IN THIS ENVIRONMENT THE CORPORATE TIT IS GONE AND YOU ARE COMPLETELY INCAPABLE OF SURVIVING ON YOUR OWN YOU THINK THESE FAILED COMPANIES HAD STUPID BUSINESS MODELS HOW ABOUT YOURSI KNEW THE ADVERTISING MARKET WAS GOING TO COLLAPSE YEARS AGO BECAUSE ITS BASED ON THE ASSUMPTION THAT BANNERS ARE EFFECTIVE THINK ABOUT IT YOU ARE ENTIRELY DEPENDANT ON ADVERTISING YET THE PEOPLE YOU TRY TO ATTRACT ARE PEOPLE WHO ARENT GOING TO CLICK ON LET ALONE BUY WHATEVER STUPID CRAP THAT IS BEING ADVERTISED I AM SURE MOST OF THE CLICKS YOU HAVE GOTTEN HAVE BEEN SYMPATHY CLICKSDID YOU ACTUALLY THINK THAT IT WAS GOING TO LAST FOREVER EVERYBODY KNOWS IT DOESNT loving WORK AND MOST SITES HAVE TO BEG THEIR READERS TO CLICK JUST TO PAY THE SERVER BILL DID YOU THINK CORPORATIONS WERENT GOING TO NOTICE THAT NO ONE WAS BUYING THEIR PRODUCTS YOURE AN IDIOT RICHARD AND I SINCERELY MEAN THATTHE CONTEMPTUOUSLY STUPID DECISIONS YOU MADE REGARDING THE VARIOUS NETWORKS YOU JOINED DONT MATTER AT ALL BECAUSE THE ENTIRE IDEA WAS FLAWED FROM THE START ENJOY YOUR LAST MOMENTS AS A FREE MAN YOULL SOON BE SHOVELLING poo poo FOR THE REST OF YOUR LIFE AT SOME NAMELESS CORPORATION A VACANT LOOK FOREVER ETCHED UPON YOUR FACEYEARS FROM NOW WHEN YOURE NO BETTER OFF THAN WHEN YOU STARTED WHEN IT FINALLY HITS YOU THAT ITS ALL BEEN NOTHING BUT A WASTED LIE THINK OF ME THINK OF ME RICHARD AND WHEN YOU DO REALIQE THAT I WAS THE ONLY BEACON OF LOGIC AND TRUTH IN THIS SAD MENAGERIE YOU SEEM PREDESTINED FOR FAILURE HOWEVER SO I DOUBT THERE IS ANYTHING ONE CAN DO FOR YOUJUST REMEMBER WHEN THE JOY IS GONE WHEN YOURE CLAWING AT THE BOUNDARIES OF YOUR LITTLE WORLD YOU ALWAYS HAD A CHOICE

yep. you got it

welcome to the crypto gang i'll create out of this. i am thinking of creating the "Bletchley Park Group" or some poo poo which will be fun

from this point forward, i am going to create new threads every once in a while with challenges. those who are the first to complete them successfully will end up with the gang tag under their current title. i am working on a new cipher at the moment so stay put

if someone creates a gang tag that i like using the gang tag as a theme, i may consider it

also old australian dial pads used to have 'q' and 'z' on 1

# ? Mar 18, 2015 21:33

oh no blimp issue: Feb 23, 2011

OSI bean dip posted:

yep. you got it

welcome to the crypto gang i'll create out of this. i am thinking of creating the "Bletchley Park Group" or some poo poo which will be fun

from this point forward, i am going to create new threads every once in a while with challenges. those who are the first to complete them successfully will end up with the gang tag under their current title. i am working on a new cipher at the moment so stay put

if someone creates a gang tag that i like using the gang tag as a theme, i may consider it

do i get an honorary membership because i live next door to bletchley park?

# ? Mar 18, 2015 21:35

pr0zac: Jan 18, 2004; ~*lukecagefan69*~; Pillbug

the lovely speed written python I used to decrypt it:

code:

#f = open('encrypted.txt', 'r')
#line = f.read().replace('\n', '')

line = "8b6f5c8e7a3e0a2f7a0d8c5e6b0d2c6d"

start_num = 0

split = [line[i:i+2] for i in range(0, len(line), 2)]

nti = {'a':0, 'b':1, 'c':2, 'd':3, 'e':4, 'f':5}

d = {
    1 : 'QZ',
    2 : 'ABC',
    3 : 'DEF',
    4 : 'GHI',
    5 : 'JKL',
    6 : 'MNO',
    7 : 'PRS',
    8 : 'TUV',
    9 : 'WXY',
    0 : ' ',
}

while start_num < 10:
    print("Start_num is %d" % start_num)

    num = start_num
    fixed = ""
    for pair in split:
        first = pair[0]
        decoded = (int(first) - num) % 10
        rotate = nti[pair[1]] % len(d[decoded])
        num = num + 1
        fixed = '%s%s' % (fixed, d[decoded][rotate])

    print(fixed)
    start_num = start_num + 1

ran it on just the first line, looked at results that looked like sane human readable text, ran it with just that start number against the whole thing to get the result

pr0zac fucked around with this message at 21:52 on Mar 18, 2015

# ? Mar 18, 2015 21:35

Share Bear: Apr 27, 2004

oh my keypad was wrong

oh well

# ? Mar 18, 2015 21:50

Share Bear: Apr 27, 2004

hey im a big idiot back to work

# ? Mar 18, 2015 21:52

Jonny 290: May 5, 2005; [ASK] me about OS/2 Warp

I was expecting a puzzle, not a riddle.

I still do not understand what the gently caress an australian telephone dial has to do with any of this.

# ? Mar 18, 2015 22:03

GameCube: Nov 21, 2006

i'm just gonna buy myself the gang tag. way easier

# ? Mar 18, 2015 22:05

Subjunctive: Sep 12, 2006; ✨sparkle and shine✨

nice, pr0zac.

so what determines that the first pair in the example is 0e and not 0b? they decode the same way, IIUC, and it's not clear to me how the encoding would produce one rather than the other.

# ? Mar 18, 2015 22:06

Bloody: Mar 3, 2013

I am glad I wasted no additional time on this

sec through obscurity works

# ? Mar 18, 2015 22:08

pr0zac: Jan 18, 2004; ~*lukecagefan69*~; Pillbug

Subjunctive posted:

nice, pr0zac.

so what determines that the first pair in the example is 0e and not 0b? they decode the same way, IIUC, and it's not clear to me how the encoding would produce one rather than the other.

the second "digit" specifies which letter for that number on the dial to select, so b = the 2nd and e = 5th, modded by the amount of letters for that number, so for number with 3 letters 5 becomes 2

ie: 4a = G, 4b = H, 4c = I, 4d = G, 4e = H, 4f = I

# ? Mar 18, 2015 22:09

Subjunctive: Sep 12, 2006; ✨sparkle and shine✨

pr0zac posted:

the second "digit" specifies which letter for that number on the dial to select, so b = the 2nd and e = 5th, modded by the amount of letters for that number, so for number with 3 letters 5 becomes 2

ie: 4a = G, 4b = H, 4c = I, 4d = G, 4e = H, 4f = I

right, but that means that when encoding H you could produce either 4b or 4e. what causes the encryption algorithm to select one rather than the other?

# ? Mar 18, 2015 22:12

pr0zac: Jan 18, 2004; ~*lukecagefan69*~; Pillbug

Subjunctive posted:

right, but that means that when encoding H you could produce either 4b or 4e. what causes the encryption algorithm to select one rather than the other?

in the example case it looks like it just switches between a-c or d-f every pair

# ? Mar 18, 2015 22:17

Lain Iwakura: Aug 5, 2004; The body exists only to verify one's own existence.; Taco Defender

Subjunctive posted:

nice, pr0zac.

so what determines that the first pair in the example is 0e and not 0b? they decode the same way, IIUC, and it's not clear to me how the encoding would produce one rather than the other.

it's just flipping it back and forth the whole time to offer a level of obscuration. it's to lead people to believe that they're md5s or lm hashes and not something else. at the end of the day it doesn't really matter for the decoding process which way it is

i'd hate to imagine that when i used the similar encoder on the ctf i was involved with the past few days that someone decided to ram a gpu against it

Lain Iwakura fucked around with this message at 22:28 on Mar 18, 2015

# ? Mar 18, 2015 22:17

CRIP EATIN BREAD: Jun 24, 2002; Hey stop worrying bout my acting bitch, and worry about your WACK ass music. In the mean time... Eat a hot bowl of Dicks! Ice T; Soiled Meat

security through obscurity

# ? Mar 18, 2015 22:42

spankmeister: Jun 15, 2008

loving babypf fuuuuck

# ? Mar 18, 2015 22:43

Subjunctive: Sep 12, 2006; ✨sparkle and shine✨

I would be interested in another challenge, this time for dumbs.

# ? Mar 18, 2015 22:57

sleepy gary: Jan 11, 2006

Subjunctive posted:

I would be interested in another challenge, this time for dumbs.

yeah but really dumb, such as myself

# ? Mar 18, 2015 23:01

oh no blimp issue: Feb 23, 2011

DNova posted:

yeah but really dumb, such as myself

like never none any cryptography dumb

# ? Mar 18, 2015 23:05

Share Bear: Apr 27, 2004

http://cryptopals.com just do this it was already posted

edit: they gotta loving add www to their wildcard dns, more proof you can gently caress up anything no matter how good you are at other stuff

# ? Mar 18, 2015 23:23