This is a preview version of the DisplayLink DL-7450 Software Development Kit Documentation. The functionality that is described and made available in this version is subject to addition, removal or change without warning.

hashlib – hashing algorithms

This module is a partial implementation of the corresponding CPython hashlib module, and contains some common binary data hashing algorithms. This module is part of the MicroPython core library.

• SHA256 - The current generation, modern hashing algorithm (of SHA2 series). It is suitable for cryptographically-secure purposes.

• SHA1 - A previous generation algorithm. Not recommended for new usages.

• MD5 - A legacy algorithm, not considered cryptographically secure.

Constructors

In all of the following, data is any object that satisfies the buffer protocol, including string, byte, bytearray or memoryview objects.

class hashlib.sha256([data])

Create an SHA256 hasher object and optionally feed data into it.

class hashlib.sha1([data])

Create an SHA1 hasher object and optionally feed data into it.

class hashlib.md5([data])

Create an MD5 hasher object and optionally feed data into it.

import hashlib
from splashscreen import Splashscreen

screen = Splashscreen()
hash = hashlib.md5(b"hello, world")
screen.add_text_box(f"digest: {hash.digest()}")

# displays:
# digest: b'\xe4\xd7\xf1\xb4\xed.B\xd1X\x98\xf4\xb2{\x01\x9d\xa4'

Methods

In all of the following, data is any object that satisfies the buffer protocol, including string, byte, bytearray or memoryview objects.

hash.update(data)

Feed more binary data into hash.

import hashlib
from splashscreen import Splashscreen

screen = Splashscreen()
hash = hashlib.md5(b"hello")
hash.update(b", world")
screen.add_text_box(f"digest: {hash.digest()}")

# displays:
# digest: b'\xe4\xd7\xf1\xb4\xed.B\xd1X\x98\xf4\xb2{\x01\x9d\xa4'

hash.digest()

Return hash for all data passed through hash, as a bytes object. After this method is called, no more data be fed into the hash.

import hashlib

hash = hashlib.md5(b"hello")
digest = hash.digest()

# either of the following calls results in an error
# hash.update(b", world")
# hash.digest()

hash.hexdigest()

This method is NOT implemented. Use binascii.hexlify(hash.digest()) to achieve a similar effect.

import hashlib
from binascii import hexlify
from splashscreen import Splashscreen

screen = Splashscreen()
hash = hashlib.md5(b"hello, world")

# The following line results in an error
# screen.add_text_box(f"hexdigest: {hash.hexdigest()}")

# Use this instead:
screen.add_text_box(f"hexdigest: {hexlify(hash.digest())}")

# displays
# hexdigest: b'e4d7f1b4ed2e42d15898f4b27b019da4'