An attempt to solve Tom's Data Onion
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\_______/ \_______| \____/ \_______|
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\______/ \__| \__|\__| \______/ \__| \__|
_...-----.._ |/ /
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| ##########
>>> A PROGRAMMING PUZZLE IN A TEXT FILE <<<
Version 1.1.3
by @tom_dalling
https://tomdalling.com/toms-data-onion/
==[ Introduction ]==========================================
At the bottom of this file you will find a payload -- a blob
of data that has been obfuscated in some way. When it is
decoded correctly, the payload will turn into another text
file with another puzzle. There are many puzzles wrapped
inside each other, like a matryoshka doll, or the layers of
an onion.
You will need to write code to do the decoding. This can be
done using any programming language.
Every layer clearly explains how to decode its payload.
These are puzzles with deterministic solutions, like Sudoku,
not riddles. I'm a software developer, not the sphinx of
Thebes.
There is a little bit of educational value in each layer. In
order to progress, you will need to learn and use computery
concepts like bitwise operations, encodings, cryptography,
error detection, and so on.
==[ Warning ]===============================================
After peeling away all the layers, you will discover...
THECO R E THE COR ETH ECO RETH
E C O R E T H E C O R
E T H E C O R E T H
E CORE THE C O R ETH ECOR
E T H E C O R E T H E
C O R ETH ECO RET H E CORE
I've hidden something at the core of this puzzle --
something that I probably should not have published --
something that, if you read it, you might wish that you
hadn't. This may land me in serious trouble, but I can't
sleep easy at night holding on to this secret. You have been
warned.
==[ Hashtag ]===============================================
Use the hashtag #TomsDataOnion to share your progress on
social media, or to see what others are saying.
==[ Changelog ]=============================================
* 2020-08-06 -- v1.1.3
Fixed a couple of typos in the layer 6 documentation. The
typos do not affect the solution.
* 2020-07-26 -- v1.1.2
Fixed some incorrect example values in layer 2.
* 2020-07-16 -- v1.1.1
Prevented obstacles in layer 4 from overlapping, so that
they must be handled individually. Also tweaked layer 5,
because it wasn't sufficiently scrambling the next layer
when decoded incorrectly.
* 2020-07-05 -- v1.1
Added monstrous new layer to the end. This is the
crowning jewel of the puzzle. Also made clarifications
and fixed grammar mistakes in the instructions for some
layers.
* 2020-06-17 -- v1.0
Initial public release, with five layers.
* 2020-06-12 -- v0.1 alpha
Work-in-progress release for alpha testers.
==[ Layer 0/6: ASCII85 ]====================================
ASCII85 is a binary-to-text encoding. These encodings are
useful when you need to send arbitrary binary data as text,
such as sending an image as an email attachment, or
embedding obfuscated data in a text file. It takes four
bytes of binary data, and converts them into five printable
ASCII characters. The encoding only uses 85 "safe" ASCII
characters, hence its name.
----------------------------------------------------
This payload has been encoded with Adobe-flavoured ASCII85.
All subsequent layers are ASCII85 encoded just like this
one, but they require additional processing in order to be
solved.
Decode the payload below to proceed!
==[ Payload ]===============================================
See: payload.txt