[device] CW340 support

This PR adds experimental CW340 support with a minimal running
capture script.

Signed-off-by: Pascal Nasahl <[email protected]>

Author: nasahlpa

cw/simple_capture_aes_sca_cw340.py

@@ -0,0 +1,163 @@
+#!/usr/bin/env python3
+# Copyright lowRISC contributors.
+# Licensed under the Apache License, Version 2.0, see LICENSE for details.
+# SPDX-License-Identifier: Apache-2.0
+import binascii
+import random
+import signal
+import sys
+import time
+from datetime import datetime
+from functools import partial
+from pathlib import Path
+
+import chipwhisperer as cw
+import numpy as np
+import yaml
+from Crypto.Cipher import AES
+from tqdm import tqdm
+
+from util import device, plot, trace_util
+
+
+def abort_handler_during_loop(project, sig, frame):
+    # Handler for ctrl-c keyboard interrupts
+    # TODO: Has to be modified according to database (i.e. CW project atm) used
+    if project is not None:
+        print("\nHandling keyboard interrupt")
+        project.close(save=True)
+    sys.exit(0)
+
+
+if __name__ == '__main__':
+    # Load configuration from file
+    with open('simple_capture_aes_sca_cw340.yaml') as f:
+        cfg = yaml.load(f, Loader=yaml.FullLoader)
+
+    USE_HUSKY = True
+
+    # Create ChipWhisperer project for storage of traces and metadata
+    project = cw.create_project(cfg["capture"]["project_name"], overwrite=True)
+
+    # Create OpenTitan encapsulating ChipWhisperer Husky and FPGA
+    # NOTE: A clean separation of the two seems infeasible since
+    # scope needs FPGA (PLL?) to be configured and target constructor needs scope as input.
+    cwfpgahusky = device.OpenTitan(cfg["cwfpgahusky"]["fpga_bitstream"],
+                                   cfg["cwfpgahusky"]["force_program_bitstream"],
+                                   cfg["cwfpgahusky"]["fw_bin"],
+                                   cfg["cwfpgahusky"]["pll_frequency"],
+                                   cfg["cwfpgahusky"]["baudrate"],
+                                   cfg["cwfpgahusky"]["scope_gain"],
+                                   cfg["cwfpgahusky"]["num_samples"],
+                                   cfg["cwfpgahusky"]["offset"],
+                                   cfg["cwfpgahusky"]["output_len_bytes"])
+
+
+    # Register ctrl-c handler to store traces on abort
+    signal.signal(signal.SIGINT, partial(abort_handler_during_loop, project))
+
+    # Preparation of Key and plaintext generation
+    # Generate key at random based on test_random_seed (not used atm)
+    random.seed(cfg["test"]["test_random_seed"])
+    key = bytearray(cfg["test"]["key_len_bytes"])
+    for i in range(0, cfg["test"]["key_len_bytes"]):
+        key[i] = random.randint(0, 255)
+    # Load initial key and text values from cfg
+    key = bytearray(cfg["test"]["key"])
+    print(f'Using key: {binascii.b2a_hex(bytes(key))}')
+    text = bytearray(cfg["test"]["text"])
+    # Prepare generation of new texts/keys by encryption using key_for_generation
+    key_for_gen = bytearray(cfg["test"]["key_for_gen"])
+    cipher_gen = AES.new(bytes(key_for_gen), AES.MODE_ECB)
+
+    # Set key
+    cwfpgahusky.target.simpleserial_write("k", key)
+
+    # Cipher to compute expected responses
+    cipher = AES.new(bytes(key), AES.MODE_ECB)
+
+    # # Main loop for measurements with progress bar
+    # for _ in tqdm(range(cfg["capture"]["num_traces"]), desc='Capturing', ncols=80):
+
+    #     # TODO: Useful code line for batch capture
+    #     # cwfpgahusky..simpleserial_write("s", capture_cfg["batch_prng_seed"].to_bytes(4, "little"))
+
+    #     # Note: Capture performance tested Oct. 2023:
+    #     #   Using husky with 1200 samples per trace leads to 48 it/s
+    #     #   Using Waverunner with 1200 - 50000 samples per trace leads to 27 it/s
+    #     #       Increases to 31 it/s when 'Performance' set to 'Analysis' in Utilies->Preferences
+    #     #       Transfer over UART only slows down if .e.g transfering key 5 additional times
+
+    #     if USE_HUSKY:
+    #         # Arm Husky scope
+    #         cwfpgahusky.scope.arm()
+
+    #     # Generate new text for this iteration
+    #     text = bytearray(cipher_gen.encrypt(text))
+    #     # Load text and trigger execution
+    #     cwfpgahusky.target.simpleserial_write('p', text)
+
+    #     if USE_HUSKY:
+    #         # Capture Husky trace
+    #         ret = cwfpgahusky.scope.capture(poll_done=False)
+    #         i = 0
+    #         while not cwfpgahusky.target.is_done():
+    #             i += 1
+    #             time.sleep(0.05)
+    #             if i > 100:
+    #                 print("Warning: Target did not finish operation")
+    #         if ret:
+    #             print("Warning: Timeout happened during capture")
+
+    #         # Get Husky trace
+    #         wave = cwfpgahusky.scope.get_last_trace(as_int=True)
+
+    #     if USE_WAVERUNNER:
+    #         # Capture and get Waverunner trace
+    #         waves = waverunner.capture_and_transfer_waves()
+    #         assert waves.shape[0] == cfg["waverunner"]["num_segments"]
+    #         # For single capture, 1st dim contains wave data
+    #         wave = waves[0, :]
+    #         # Put into uint8 range
+    #         wave = wave + 128
+
+    #     # Get response from device and verify
+    #     response = cwfpgahusky.target.simpleserial_read('r',
+    #                                                     cwfpgahusky.target.output_len, ack=False)
+    #     if binascii.b2a_hex(response) != binascii.b2a_hex(cipher.encrypt(bytes(text))):
+    #         raise RuntimeError(f'Bad ciphertext: {response} != {cipher.encrypt(bytes(text))}.')
+
+    #     # TODO: Useful code line for batch capture
+    #     # waves = scope.capture_and_transfer_waves()
+
+    #     # Sanity check retrieved data (wave) and create CW Trace
+    #     if len(wave) >= 1:
+    #         trace = cw.Trace(wave, text, response, key)
+    #     else:
+    #         raise RuntimeError('Capture failed.')
+
+    #     if USE_HUSKY:
+    #         # Check if ADC range has been exceeded for Husky.
+    #         # Not done for WaveRunner because clipping can be inspected on screen.
+    #         trace_util.check_range(trace.wave, cwfpgahusky.scope.adc.bits_per_sample)
+
+    #     # Append CW trace to CW project storage
+    #     if USE_HUSKY:
+    #         project.traces.append(trace, dtype=np.uint16)
+    #     if USE_WAVERUNNER:
+    #         # Also use uint16 as dtype so that tvla processing works
+    #         project.traces.append(trace, dtype=np.uint16)
+
+    # # Save metadata and entire configuration cfg to project file
+    # project.settingsDict['datetime'] = datetime.now().strftime("%m/%d/%Y, %H:%M:%S")
+    # project.settingsDict['cfg'] = cfg
+    # sample_rate = int(round(cwfpgahusky.scope.clock.adc_freq, -6))
+    # project.settingsDict['sample_rate'] = sample_rate
+    # project.save()
+
+    # # Create and show test plot
+    # if cfg["capture"]["show_plot"]:
+    #     plot.save_plot_to_file(project.waves, None, cfg["capture"]["plot_traces"],
+    #                            cfg["capture"]["trace_image_filename"], add_mean_stddev=True)
+    #     print(f'Created plot with {cfg["capture"]["plot_traces"]} traces: '
+    #           f'{Path(cfg["capture"]["trace_image_filename"]).resolve()}')

cw/simple_capture_aes_sca_cw340.yaml

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+cwfpgahusky:
+  baudrate: 115200
+  output_len_bytes: 16
+  pll_frequency: 100000000
+  adc_mul: 2
+  num_segments: 1
+  num_samples: 1200
+  offset: -40
+  scope_gain: 31.5
+capture:
+  scope_select: husky
+  num_traces: 1000
+  project_name: "projects/simple_capture_aes_sca"
+  show_plot: True
+  plot_traces: 100
+  trace_image_filename: "projects/simple_capture_aes_sca_sample_traces.html"
+test:
+  key_len_bytes: 16
+  test_random_seed: 0
+  key: [0x81, 0x1E, 0x37, 0x31, 0xB0, 0x12, 0x0A, 0x78, 0x42, 0x78, 0x1E, 0x22, 0xB2, 0x5C, 0xDD, 0xF9]
+  text: [0xAA, 0xAA, 0xAA, 0xAA, 0xAA, 0xAA, 0xAA, 0xAA, 0xAA, 0xAA, 0xAA, 0xAA, 0xAA, 0xAA, 0xAA, 0xAA]
+  key_for_gen: [0x12, 0x34, 0x56, 0x78, 0x9A, 0xBC, 0xDE, 0xF1, 0x23, 0x45, 0x67, 0x89, 0xAB, 0xCD, 0xE0, 0xF0]