.. py:module:: ethereum.crypto.blake2

The Blake2 Implementation
^^^^^^^^^^^^^^^^^^^^^^^^^^


.. only:: stage1

Module Contents
---------------

Classes
~~~~~~~

.. autoapisummary::

   ethereum.crypto.blake2.Blake2
   ethereum.crypto.blake2.Blake2b



Functions
~~~~~~~~~

.. autoapisummary::
   :nosignatures:

   ethereum.crypto.blake2.spit_le_to_uint



Module Details
---------------

spit_le_to_uint
~~~~~~~~~~~~~~~


.. function:: spit_le_to_uint(data: bytes, start: int, num_words: int) -> List[ethereum.base_types.Uint]
   :noindexentry:

   Extracts 8 byte words from a given data.

   :param data: The data in bytes from which the words need to be extracted
   :param start: Position to start the extraction
   :param num_words: The number of words to be extracted




.. undocinclude:: /../src/ethereum/crypto/blake2.py
   :language: python
   :pyobject: spit_le_to_uint

Blake2
~~~~~~


Implementation of the BLAKE2 cryptographic hashing algorithm.

Please refer the following document for details:
https://datatracker.ietf.org/doc/html/rfc7693


.. class:: Blake2

   

   .. py:attribute:: w
         :annotation: :int

      

   

   .. py:attribute:: mask_bits
         :annotation: :int

      

   

   .. py:attribute:: word_format
         :annotation: :str

      

   

   .. py:attribute:: R1
         :annotation: :int

      

   

   .. py:attribute:: R2
         :annotation: :int

      

   

   .. py:attribute:: R3
         :annotation: :int

      

   

   .. py:attribute:: R4
         :annotation: :int

      

   

   .. py:attribute:: sigma
         :annotation: :Tuple = [[0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15], [14, 10, 4, 8, 9, 15, 13, 6, 1, 12, 0,...

      

   

   .. py:attribute:: IV
         :annotation: :Tuple = [7640891576956012808, 13503953896175478587, 4354685564936845355, 11912009170470909681,...

      

   .. py:method:: max_word() -> int
      :property:

      Largest value for a given Blake2 flavor.


   .. py:method:: w_R1() -> int
      :property:

      (w - R1) value for a given Blake2 flavor.
      Used in the function G


   .. py:method:: w_R2() -> int
      :property:

      (w - R2) value for a given Blake2 flavor.
      Used in the function G


   .. py:method:: w_R3() -> int
      :property:

      (w - R3) value for a given Blake2 flavor.
      Used in the function G


   .. py:method:: w_R4() -> int
      :property:

      (w - R4) value for a given Blake2 flavor.
      Used in the function G


   .. py:method:: sigma_len() -> int
      :property:

      Length of the sigma parameter.


   .. py:method:: get_blake2_parameters(data: bytes) -> Tuple

      Extract the parameters required in the Blake2 compression function
      from the provided bytes data.

      :param data: The bytes data that has been passed in the message.


   .. py:method:: G(v: List, a: int, b: int, c: int, d: int, x: int, y: int) -> List

      The mixing function used in Blake2
      https://datatracker.ietf.org/doc/html/rfc7693#section-3.1

      :param v: The working vector to be mixed.
      :param a: Indexes within v of the words to be mixed.
      :param b: Indexes within v of the words to be mixed.
      :param c: Indexes within v of the words to be mixed.
      :param d: Indexes within v of the words to be mixed.
      :param x: The two input words for the mixing.
      :param y: The two input words for the mixing.


   .. py:method:: compress(num_rounds: ethereum.base_types.Uint, h: List[ethereum.base_types.Uint], m: List[ethereum.base_types.Uint], t_0: ethereum.base_types.Uint, t_1: ethereum.base_types.Uint, f: bool) -> bytes

      'F Compression' from section 3.2 of RFC 7693:
      https://tools.ietf.org/html/rfc7693#section-3.2

      :param num_rounds: The number of rounds. A 32-bit unsigned big-endian word
      :param h: The state vector. 8 unsigned 64-bit little-endian words
      :param m: The message block vector. 16 unsigned 64-bit little-endian words
      :param t_0: Offset counters. 2 unsigned 64-bit little-endian words
      :param t_1: Offset counters. 2 unsigned 64-bit little-endian words
      :param f: The final block indicator flag. An 8-bit word




Blake2b
~~~~~~~


The Blake2b flavor (64-bits) of Blake2.
This version is used in the pre-compiled contract.


.. class:: Blake2b

   Bases: :py:obj:`Blake2`

   

   .. py:attribute:: w
         :annotation: :int = 64

      

   

   .. py:attribute:: mask_bits
         :annotation: :int = 18446744073709551615

      

   

   .. py:attribute:: word_format
         :annotation: :str = Q

      

   

   .. py:attribute:: R1
         :annotation: :int = 32

      

   

   .. py:attribute:: R2
         :annotation: :int = 24

      

   

   .. py:attribute:: R3
         :annotation: :int = 16

      

   

   .. py:attribute:: R4
         :annotation: :int = 63