This is a straightforward Python wrapper for ssdeep by Jesse Kornblum, which is a library for computing context triggered piecewise hashes (CTPH). Also called fuzzy hashes, CTPH can match inputs that have homologies. Such inputs have sequences of identical bytes in the same order, although bytes in between these sequences may be different in both content and length.
To compute a fuzzy hash, use hash
function:
>>> import ssdeep >>> hash1 = ssdeep.hash('Also called fuzzy hashes, Ctph can match inputs that have homologies.') >>> hash1 '3:AXGBicFlgVNhBGcL6wCrFQEv:AXGHsNhxLsr2C' >>> hash2 = ssdeep.hash('Also called fuzzy hashes, CTPH can match inputs that have homologies.') >>> hash2 '3:AXGBicFlIHBGcL6wCrFQEv:AXGH6xLsr2C'
The compare
function returns the match between 2 hashes, an integer value from 0 (no match) to 100.
>>> ssdeep.compare(hash1, hash2) 22
The hash_from_file
accepts filename as argument and calculates the hash of the contents of the file.
>>> ssdeep.hash_from_file('/etc/resolv.conf') '3:S3yE29cFrrMOoiECAaHJgvn:S3m+COoiUCuvn'
This wrapper includes the unchanged source distribution of ssdeep version 2.9 and has no external dependencies.
To build the package the following dependencies have to be installed.
- Python 2.7 or Python 3.x including development files
- gcc and build essentials
- Cython
If all requirements are met it is possible to install the wrapper by using pip or easy_install.
pip install ssdeep
When comparing two hashes the result is always 0
The result depends on the algorithms in the ssdeep library. There are some issues if the length of provided data is to short or if the algorithm could not find enough patterns.
The following example must not return the expected value.
>>> hash1 = ssdeep.hash('foo'*4096) >>> hash2 = ssdeep.hash('foo'*4096) >>> ssdeep.compare(hash1, hash2) 0
The code is licensed under the terms of the GPLv2.
The initial version was published in 2010 by Denis Bilenko on bitbucket. Since 2012 the source is maintained by Philipp Seidel(DinoTools) and has been published on github.