Develop tools that allow a Bitcoin private key to be stored with an arithmetic checksum tree. This makes private key storage more robust, because transcription errors can be located and fixed.







- Goal
- Contents
- Brief Summary
- Summary
- Downloadable Assets
- How To Use The Tools
- Project Log







I developed two tools:
- private_key_to_storage_key.py
- storage_key_to_private_key.py
that allow a user to a) add an arithmetic checksum tree to a Bitcoin private key and b) validate the checksum tree and remove it.







I developed two tools:
- private_key_to_storage_key.py
- storage_key_to_private_key.py
that allow a user to a) add an arithmetic checksum tree to a Bitcoin private key and b) validate the checksum tree and remove it.

In the previous project An investigation into recovering from transcription errors in Bitcoin private keys, I investigated the use of an arithmetic checksum tree in Bitcoin private key storage, and found that it greatly helped to locate transcription errors and increase key recovery speed.

A Bitcoin private key in several different formats:

1) Normal format:


2) Grid pattern:


3) Grid pattern with an added arithmetic checksum tree:


I refer to a Bitcoin private key in format (3) as a "storage key".

A Bitcoin private key is 32 bytes. When written in hex characters, as in format (1), it is 64 bytes.

There are 107 bytes in the storage key (not counting the last newline byte). This is a data size increase of ~67%.

The code used in this recipe has been run in Python 2.7.5 on CentOS 7.6 and in Python 2.7.13 on Mac OS X 10.6.8. It should run successfully in Python 2.7.x.











Assets of this article:

List:



Asset: A script that generates an arithmetic checksum tree to a Bitcoin private key. It will print out the key in a grid format with the checksum tree added above the key.
private_key_to_storage_key.py

Asset: A script that validates a checksum tree stored with a key, then removes it. It will print out the key without the tree and without any whitespace.
storage_key_to_private_key.py











Help commands:






Main commands:





Note: In the main commands, the flag can be used instead of and .


Example of use:






Now make a copy of and add an error. In the checksum tree, in line 3, in group 1, change character 3 to be 'f' instead of 'e'.




The error has been located and reported.























In the previous project An investigation into recovering from transcription errors in Bitcoin private keys, I investigated the use of an arithmetic checksum tree in Bitcoin private key storage, and found that it greatly helped to locate transcription errors and increase key recovery speed.

In this project, I'll develop tools for generating a checksum tree to be stored alongside a Bitcoin private key. Goals:
- Generate the checksum tree for a private key.
- Extract a private key from the checksum tree storage format.
- Check the integrity of the checksum tree.

First, I'll write write a small command-line tool that can convert a one-line Bitcoin private key to a grid-pattern Bitcoin private key with a checksum tree. Input is a file. Output is text that can be redirected to a file.

I'll call the one-line private key a "private key" and the grid-pattern key with a checksum tree a "storage key".

Input:


Output:


In the output:
- The 3 lines at the top are the checksum tree.
- The 4x4x4 grid at the bottom is the private key.

The corresponding address is:



Create a work directory.

Save the one-line private key in a file called "privateKey.txt".




How many bytes should be in a storage key?

Not counting the last newline, there should be 7 newline bytes.

There are 5 lines of 4 groups of 4 characters, with a space between group. For each line, there are a total of 3 spaces. Each line therefore has 4x4 + 3 = 19 bytes. Total bytes in 5 lines: 5 x 19 = 95

There are two remaining lines at the top of the checksum tree, one with 1 character and another with 4 characters. Total: 5 bytes.

Total bytes in the entire storage key:
7 + 95 + 5 = 107




[development occurs here]







This is the expected output.


Store this in a file.







Next: I'll write a second tool that extracts a private key from the checksum tree storage format. This second tool will also check the integrity of the checksum tree.




[development occurs here]







This is the expected output.




Let's try adding various errors to the storageKey.




Make a copy of storageKey.txt (save it as storageKey2.txt). Add an error in the private key: In line 1, group 2, change the second character (6) to "b".







Make a copy of storageKey2.txt (save it as storageKey3.txt). Add an error in the private key: In line 4, group 1, change the first character (4) to "2".







Make a copy of storageKey3.txt (save it as storageKey4.txt). Add an error in the checksum group: Change the third character (3) to "8".







Make a copy of storageKey4.txt (save it as storageKey5.txt). Add an error in the checksum line: In group 4, change the first character (1) to "7".







An extra test: In the previous project, I altered the private key slightly (by changing line 3 / group 1 / character 1 from "3" to "8", producing this new private key:



I then generated this checksum tree for it:



Save the new private key as privateKey2.txt.







This is the expected output.





The output is the new private key, as expected.




That's the end of this project.