Bench: Ascon

This module contains the documentation for the Top level Ascon model and testbench.

Ascon Model

ascon_model.py

Library for the AsconModel class.

This module contains the Python model used to verify the Ascon module.

Author: Timothée Charrier

class ascon_model.AsconModel(dut: HierarchyObject, *, inputs: dict[str, int] | None = None, plaintext: list[int] | None = None)

Model for the Ascon module.

This class defines the model used to verify the Ascon module.

Methods

ascon128(inputs)	Compute the output state based on the current input state.
permutation([i_round, is_first])	Compute the output state based on the current input state.
rotate_right(value, num_bits)	Rotate the bits of a 64-bit integer to the right.
update_inputs([inputs])	Update the input state, data, key, and enable signals of the model.
xor_data_begin(data)	Perform XOR operation at the beginning with the data.
xor_key_begin(key)	Perform XOR operation at the beginning with the key.
xor_key_end()	Perform XOR operation at the end with the key.
xor_lsb_end()	Perform XOR operation at the end with the least significant bit.

ascon128(inputs: dict[str, int]) → dict[str, str]

Compute the output state based on the current input state.

Parameters:

inputs (dict) – The input dictionary containing the data, key, and nonce.

Returns:

The output state, tag, and cipher.

Return type:

dict

permutation(i_round: int = 0, *, is_first: bool = False) → None

Compute the output state based on the current input state.

Parameters:

• i_round (int, optional) – The current round number. Default is 0.

• is_first (bool, optional) – True if it is the first permutation, False otherwise. Default is False.

static rotate_right(value: int, num_bits: int) → int

Rotate the bits of a 64-bit integer to the right.

Parameters:

• value (int) – The input value.

• num_bits (int) – The number of bits to rotate.

Returns:

The rotated value.

Return type:

int

update_inputs(inputs: dict[str, int] | None = None) → None

Update the input state, data, key, and enable signals of the model.

Parameters:

inputs (dict, optional) – The new input dictionary. Default is None.

xor_data_begin(data: int) → None

Perform XOR operation at the beginning with the data.

Parameters:

data (int) – The data to XOR with the state.

xor_key_begin(key: int) → None

Perform XOR operation at the beginning with the key.

Parameters:

key (int) – The key to XOR with the state.

xor_key_end() → None

Perform XOR operation at the end with the key.

xor_lsb_end() → None

Perform XOR operation at the end with the least significant bit.

ascon_model.convert_output_to_str(dut: HierarchyObject, cipher: list[int]) → dict[str, str]

Convert the DUT output to a string.

Parameters:

• dut (HierarchyObject) – The device under test (DUT).

• cipher (list[int]) – The cipher output.

Returns:

The DUT output as a string.

Return type:

dict

Test Ascon

test_ascon.py

Testbench for the ascon module.

This module tests the ascon top level module by comparing the output of the Python implementation with the verilog implementation.

@author: Timothée Charrier

async test_ascon.ascon_top_test(dut: HierarchyObject) → None

Test the ascon top module.

Verifies that the output is correctly computed.

Parameters:

dut (HierarchyObject) – The device under test (DUT).

Raises:

RuntimeError – If the DUT fails to compute the correct output.

async test_ascon.reset_dut_test(dut: HierarchyObject) → None

Test the DUT’s behavior during reset.

Verifies that the output is correctly reset and remains stable.

Parameters:

dut (HierarchyObject) – The device under test (DUT).

Raises:

RuntimeError – If the DUT fails to reset.

test_ascon.test_ascon() → None

Function Invoked by the test runner to execute the tests.

Raises:

RuntimeError – If the test fails to build or run.