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Hash utility to create Cryptographic Linkage Keys

Project description

CLK Hash

Python implementation of cryptographic longterm key hashing. Supports Python versions 2.7+, 3.5+

This is as described by Rainer Schnell, Tobias Bachteler, and Jörg Reiher in A Novel Error-Tolerant Anonymous Linking Code

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Install clkhash with all dependencies using pip:

pip install clkhash

If the installation of bitarray fails on Windows you may need to install the appropriate Visual Studio C++ compiler for your version of Python; this is required because the bitarray library compiles a C extension.


CLI Tool

After installation of the clkhash library you should have a clkutil program in your path. Alternatively you can use python -m clkhash.cli.

This command line tool can be used to process PII data into Cryptographic Longterm Keys. The tool also has an option for generating fake PII data, and commands to upload hashes to an entity matching service.

$ clkutil generate 1000 fake-pii-out.csv
$ head -n 4  fake-pii-out.csv
0,Libby Slemmer,1933/09/13,F
1,Garold Staten,1928/11/23,M
2,Yaritza Edman,1972/11/30,F

A schema is required to hash this data. You can retrieve the default schema with

$ clkutil generate-default-schema fake-pii-schema.json

or you can make your own.

To hash this data using its schema, with the shared secret keys horse and staple:

$ clkutil hash fake-pii-out.csv horse staple fake-pii-schema.json /tmp/fake-clk.json
CLK data written to /tmp/fake-clk.json

Note the keys should only be shared with the other entity - and not with anyone carrying out the record linkage.

To use the command line tool without installing clkhash, install the dependencies, then run:

python -m clkhash.cli

clkhash api

To hash a CSV file of entities using the default schema:

from clkhash import clk, randomnames
fake_pii_schema = randomnames.NameList.SCHEMA
clks = clk.generate_clk_from_csv(open('fake-pii-out.csv','r'), ('key1', 'key2'), fake_pii_schema)

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Filename, size & hash SHA256 hash help File type Python version Upload date
clkhash-0.12.1-py2.py3-none-any.whl (1.9 MB) Copy SHA256 hash SHA256 Wheel py2.py3
clkhash-0.12.1.tar.gz (1.9 MB) Copy SHA256 hash SHA256 Source None

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