TLSH (C++ Python extension)
Project description
TLSH - C++ extension for Python
TLSH (Trend Micro Locality Sensitive Hash) is a fuzzy matching library. Given a byte stream with a minimum length of 50 bytes TLSH generates a hash value which can be used for similarity comparisons. Similar objects will have similar hash values which allows for the detection of similar objects by comparing their hash values. Note that the byte stream should have a sufficient amount of complexity. For example, a byte stream of identical bytes will not generate a hash value.
Usage
import tlsh
tlsh.hash(data)
Note that in default mode the data must contain at least 50 bytes to generate a hash value and that
it must have a certain amount of randomness.
If you use the "conservative" option, then the data must contain at least 256 characters.
For example, tlsh.hash(str(os.urandom(256)))
, should always generate a hash.
To get the hash value of a file, try tlsh.hash(open(file, 'rb').read())
.
tlsh.diff(h1, h2)
tlsh.diffxlen(h1, h2)
The diffxlen
function removes the file length component of the tlsh header from
the comparison. If a file with a repeating pattern is compared to a file
with only a single instance of the pattern, then the difference will be increased
if the file lenght is included. But by using the diffxlen
function, the file
length will be removed from consideration.
Example
import tlsh
h1 = tlsh.hash(data)
h2 = tlsh.hash(similar_data)
score = tlsh.diff(h1, h2)
h3 = tlsh.Tlsh()
with open('file', 'rb') as f:
for buf in iter(lambda: f.read(512), b''):
h3.update(buf)
h3.final()
assert h3.diff(h) == 0
score = h3.diff(h1)
Project details
Release history Release notifications | RSS feed
Download files
Download the file for your platform. If you're not sure which to choose, learn more about installing packages.