Changes

User scripts allows partial (i.e{{Warningbox|For the older V3.x tools, see [[V3: setting up the environment) or total automation of the execution flow. Making_Scripts]]}}

A basic script would look == Scripting with ChipWhisperer as a python module == When used without the GUI, the 4.0 API removes much of the high level abstractions so you can have more control over the capture process. It also answers questions like --when I capture a trace in what order are things happening? The following example scripts will give you a starting point when scripting with the ChipWhisperer tool. All these examples on this:page can be found in their home <code>chipwhisperer/software/scripting-examples</code>.

import sys=== Perform Some Traces during AES encryption and get the results as Numpy array ===from chipwhisperer.common.api.CWCoreAPI import CWCoreAPI # Import This script is an example of using the ChipWhisperer APIimport <code>chipwhisperer</code> module for capturing traces during AES encryption.capture.ui.CWCaptureGUI as cwc # Import <b>Make sure to have the ChipWhispererCapture GUIfrom chipwhisperer.common.scripts.base import UserScriptBasefrom chipwhisperer.commoncorrect firmware loaded on the target.utils</b> These traces are then saved and loaded later for analysis.parameter import Parameter

def __init__(self, api):import numpy as np super(UserScript, self)import matplotlib.__init__(api)pyplot as pltfrom datetime import datetimefrom tqdm import tqdm

def run(self):import chipwhisperer as cw #User commands here selffrom chipwhisperer.apicapture.setParameter(['Generic Settings', 'Scope Module', 'ChipWhisperer/OpenADC']) selfacq_patterns.api.setParameter(['Generic Settings', 'Target Module', 'Simple Serial'])basic import AcqKeyTextPattern_Basic selffrom chipwhisperer.apitests.setParameter(['Generic Settings', 'Trace Format', 'ChipWhisperer/Native'])tools_for_tests import FIRMWARE_DIR selffrom chipwhisperer.api.setParameter(['Simple Serial', 'Connection', 'ChipWhisperer-Lite']) self.api.setParameter(['ChipWhisperer/OpenADC', 'Connection', 'ChipWhisperer-Lite']) self.api.connect() #Example of using a list to set parameters. Slightly easier to copy/paste in this format lstexample = [['CW Extra Settings', 'Trigger Pins', 'Target IO4 (Trigger Line)', True], ['CW Extra Settings', 'Target IOn Pins', 'Target IO1', 'Serial RXD'], ['CW Extra Settings', 'Target IOn Pins', 'Target IO2', 'Serial TXD'], ['OpenADC', 'Clock Setup', 'CLKGEN Settings', 'Desired Frequency', 7370000.0], ['CW Extra Settings', 'Target HS IO-Out', 'CLKGEN'], ['OpenADC', 'Clock Setup', 'ADC Clock', 'Source', 'CLKGEN x4 via DCM'], ['OpenADC', 'Trigger Setup', 'Total Samples', 3000], ['OpenADC', 'Trigger Setup', 'Offset', 1250], ['OpenADC', 'Gain Setting', 'Setting', 45], ['OpenADC', 'Trigger Setup', 'Mode', 'rising edge'], #Final step: make DCMs relock in case they are lost ['OpenADC', 'Clock Setup', 'ADC Clock', 'Reset ADC DCM', None], ] for cmd in lstexample: self.api.setParameter(cmd) #Let's only do a few traces self.api.setParameter(['Generic Settings', 'Acquisition Settings', 'Number of Traces', 50]) #The environment is already set, lets do our first capture self.api.capture1()programmers import XMEGAProgrammer

User scripts should inherit from UserScriptBase that specifies the run() method that is called when clicking it in the menu or pressing the attack button (in the analyzer tool)# setup scope parametersscope.gain.gain = 45The API is passed as an argument by the GUI throught the constructor in order to allow the script to scope.adc.samples = 3000scope.adc.offset = 1250scope.adc.basic_mode = "remote controlrising_edge" the existing sectionscope. A name and a description should also be specifiedclock.clkgen_freq = 7370000The section scope.clock.adc_src = "if __name__ clkgen_x4"scope.trigger.triggers ="tio4"scope.io.tio1 = '__main__':" is not mandatory, but is recommended if you want to run the script from the terminalserial_rx"scope. In this case, you don't need to use the GUI, the capture can be performed using only the APIio. Extio2 = "serial_tx"scope.:io.hs2 = "clkgen"

if __name__ # program the targetprogrammer =XMEGAProgrammer()programmer.scope = '__main__':scope import sysprogrammer._logging = None from chipwhispererprogrammer.commonfind()programmer.apierase()aes_firmware_dir = os.CWCoreAPI import CWCoreAPIpath.join(FIRMWARE_DIR, 'simpleserial-aes') api aes_hex = CWCoreAPIos.path.join(aes_firmware_dir, r"simpleserial-aes-CW303.hex") # Instantiate the API apiprogrammer.runScriptClassprogram(aes_hex, memtype="flash", verify=True)programmer.close(UserScript) # Run UserScript through the API

if __name__ traces == '__main__':[] import sys from chipwhisperer.common.api.CWCoreAPI import CWCoreAPI import chipwhisperer.capture.ui.CWCaptureGUI as cwc # Import the ChipWhispererCapture GUI from chipwhisperer.common.utils.parameter import Parameter app textin = cwc.makeApplication() [] Parameter.usePyQtGraph keys = True [] api N = CWCoreAPI() 50 # Instantiate the APINumber of traces gui = cwctarget.CWAnalyzerGUIinit(api) # Instantiate the GUI gui.showfor i in tqdm(range(N) , desc='Capturing traces'): api.runScriptClass(UserScript) # Run UserScript through the APIrun aux stuff that should come before trace here

syskey, text = ktp.exitnewPair(app) # manual creation of a key, text pair can be substituted here textin.exec_append(text) keys.append(key)

These directories already have some examples which can be used target.setModeEncrypt() # only does something for targets that support it target.loadEncryptionKey(key) target.loadInput(text)  # run aux stuff that should run before the scope arms here  scope.arm()  # run aux stuff that should run after the scope arms here  target.go() timeout = 50 # wait for target to finish while target.isDone() is False and timeout: timeout -= 1 time.sleep(0.01)  try: ret = scope.capture() if ret: print('Timeout happened during acquisition') except IOError as a reference e: print('IOError: %s' % str(e))  # run aux stuff that should happen after trace here _ = target.readOutput() # clears the response from the serial port traces.append(scope.getLastTrace())trace_array = np.asarray(traces) # if you prefer to create new oneswork with numpy array for number crunchingtextin_array = np. Files put in asarray(textin)known_keys = np.asarray(keys) # for fixed key, these directories keys are scanned during all the tool initialization same now = datetime.now()fmt_string = '{:02}{:02}_{}.npy'trace_file_path = fmt_string.format(now.hour, now.minute, "traces")textin_file_path = fmt_string.format(now.hour, now.minute, "textins")keys_file_path = fmt_string.format(now.hour, now.minute, "keys") print('Saving results to {},{} and all plugin classes {}...'.format(subclass trace_file_path, textin_file_path, keys_file_path), end='')# save to a files for later processingnp.save(trace_file_path, trace_array)np.save(textin_file_path, textin_array)np.save(keys_file_path, known_keys)print('Done') # uncomment plt.show() to show an example traceplt.plot(traces[0])#plt.show() # cleanup the connection to the target and scopescope.dis()target.dis()</syntaxhighlight> ==== STM32F3 Target ====<syntaxhighlight lang=python>from __future__ import division, print_function import timeimport os import numpy as npimport matplotlib.pyplot as pltfrom datetime import datetimefrom tqdm import tqdm import chipwhisperer as cwfrom chipwhisperer.capture.acq_patterns.basic import AcqKeyTextPattern_Basicfrom chipwhisperer.tests.tools_for_tests import FIRMWARE_DIRfrom chipwhisperer.capture.api.programmers import STM32FProgrammer scope = cw.scope()target = cw.target(scope) # setup scope parametersscope.gain.gain = 45scope.adc.samples = 5000scope.adc.offset = 0scope.adc.basic_mode = "rising_edge"scope.clock.clkgen_freq = 7370000scope.clock.adc_src = "clkgen_x4"scope.trigger.triggers = "tio4"scope.io.tio1 = "serial_rx"scope.io.tio2 = "serial_tx"scope.io.hs2 = "clkgen" # program the targetprogrammer = STM32FProgrammer()programmer.scope = scopeprogrammer._logging = Noneprogrammer.open()programmer.find()programmer.erase()aes_firmware_dir = os.path.join(FIRMWARE_DIR, 'simpleserial-aes')aes_hex = os.path.join(aes_firmware_dir, r"simpleserial-aes-CW308_STM32F3.hex")programmer.program(aes_hex, memtype="flash", verify=True)programmer.close() ktp = AcqKeyTextPattern_Basic(target=target) traces = []textin = []keys = []N = 50 # Number of Plugintracestarget.init() for i in tqdm(range(N), desc='Capturing traces'): # run aux stuff that should come before trace here  key, text = ktp.newPair() # manual creation of a key, text pair can be substituted here textin.append(text) keys.append(key)  target.reinit()  target.setModeEncrypt() # only does something for targets that support it target.loadEncryptionKey(key) target.loadInput(text)  # run aux stuff that should run before the scope arms here  scope.arm()  # run aux stuff that should run after the scope arms here  target.go() timeout = 50 # wait for target to finish while target.isDone() is False and timeout: timeout -= 1 time.sleep(0.01)  try: ret = scope.capture() if ret: print('Timeout happened during acquisition') except IOError as e: print('IOError: %s' % str(e))  # run aux stuff that should happen after trace here  _ = target.readOutput() # throw out the target response traces.append(scope.getLastTrace())trace_array = np.asarray(traces) # if you prefer to work with numpy array for number crunchingtextin_array = np.asarray(textin)known_keys = np.asarray(keys) # for fixed key, these keys are all public the same now = datetime.now()fmt_string = '{:02}{:02}_{}.npy'trace_file_path = fmt_string.format(now.hour, now.minute, "traces")textin_file_path = fmt_string.format(now.hour, now.minute, "textins")keys_file_path = fmt_string.format(now.hour, now.minute, "keys") print('Saving results to {},{} and {}...'.format(trace_file_path, textin_file_path, keys_file_path), end='')# save to a files for later processingnp.save(not starting trace_file_path, trace_array)np.save(textin_file_path, textin_array)np.save(keys_file_path, known_keys)print('Done') # show an example traceplt.plot(traces[0])plt.show() # cleanup the connection to the target and scopescope.dis()target.dis()</syntaxhighlight> === Manually breaking AES encryption with your recorded traces (As much as scripting is manual) ===Using the saved traces of the AES encryption you can now break the sub-keys of the encryption key. This script is covered in more detail in [[Tutorial_B6_Breaking_AES_(Manual_CPA_Attack) | Tutorial B6]].  <syntaxhighlight lang=python>from __future__ import division, print_function import numpy as npfrom tqdm import tqdm HW = [bin(n).count("_1") for n in range(0, 256)] sbox = ( 0x63, 0x7c, 0x77, 0x7b, 0xf2, 0x6b, 0x6f, 0xc5, 0x30, 0x01, 0x67, 0x2b, 0xfe, 0xd7, 0xab, 0x76, 0xca, 0x82, 0xc9, 0x7d, 0xfa, 0x59, 0x47, 0xf0, 0xad, 0xd4, 0xa2, 0xaf, 0x9c, 0xa4, 0x72, 0xc0, 0xb7, 0xfd, 0x93, 0x26, 0x36, 0x3f, 0xf7, 0xcc, 0x34, 0xa5, 0xe5, 0xf1, 0x71, 0xd8, 0x31, 0x15, 0x04, 0xc7, 0x23, 0xc3, 0x18, 0x96, 0x05, 0x9a, 0x07, 0x12, 0x80, 0xe2, 0xeb, 0x27, 0xb2, 0x75, 0x09, 0x83, 0x2c, 0x1a, 0x1b, 0x6e, 0x5a, 0xa0, 0x52, 0x3b, 0xd6, 0xb3, 0x29, 0xe3, 0x2f, 0x84, 0x53, 0xd1, 0x00, 0xed, 0x20, 0xfc, 0xb1, 0x5b, 0x6a, 0xcb, 0xbe, 0x39, 0x4a, 0x4c, 0x58, 0xcf, 0xd0, 0xef, 0xaa, 0xfb, 0x43, 0x4d, 0x33, 0x85, 0x45, 0xf9, 0x02, 0x7f, 0x50, 0x3c, 0x9f, 0xa8, 0x51, 0xa3, 0x40, 0x8f, 0x92, 0x9d, 0x38, 0xf5, 0xbc, 0xb6, 0xda, 0x21, 0x10, 0xff, 0xf3, 0xd2, 0xcd, 0x0c, 0x13, 0xec, 0x5f, 0x97, 0x44, 0x17, 0xc4, 0xa7, 0x7e, 0x3d, 0x64, 0x5d, 0x19, 0x73, 0x60, 0x81, 0x4f, 0xdc, 0x22, 0x2a, 0x90, 0x88, 0x46, 0xee, 0xb8, 0x14, 0xde, 0x5e, 0x0b, 0xdb, 0xe0, 0x32, 0x3a, 0x0a, 0x49, 0x06, 0x24, 0x5c, 0xc2, 0xd3, 0xac, 0x62, 0x91, 0x95, 0xe4, 0x79, 0xe7, 0xc8, 0x37, 0x6d, 0x8d, 0xd5, 0x4e, 0xa9, 0x6c, 0x56, 0xf4, 0xea, 0x65, 0x7a, 0xae, 0x08, 0xba, 0x78, 0x25, 0x2e, 0x1c, 0xa6, 0xb4, 0xc6, 0xe8, 0xdd, 0x74, 0x1f, 0x4b, 0xbd, 0x8b, 0x8a, 0x70, 0x3e, 0xb5, 0x66, 0x48, 0x03, 0xf6, 0x0e, 0x61, 0x35, 0x57, 0xb9, 0x86, 0xc1, 0x1d, 0x9e, 0xe1, 0xf8, 0x98, 0x11, 0x69, 0xd9, 0x8e, 0x94, 0x9b, 0x1e, 0x87, 0xe9, 0xce, 0x55, 0x28, 0xdf, 0x8c, 0xa1, 0x89, 0x0d, 0xbf, 0xe6, 0x42, 0x68, 0x41, 0x99, 0x2d, 0x0f, 0xb0, 0x54, 0xbb, 0x16)  def intermediate(pt, keyguess): return sbox[pt ^ keyguess] # put the actual file names in herekeys = np.load('1147_keys.npy')textins = np.load('1147_textins.npy')traces = np.load('1147_traces.npy') knownkey = keys[0] # for fixed key they are loadedall the samept = textinsnumtraces = np. shape(traces)[0]Scripts autonumpoint = np.shape(traces)[1] bestguess = [0] * 16pge = [256] * 16for bnum in tqdm(range(0, 16), desc='Attacking subkeys'): cpaoutput = [0] * 256 maxcpa = [0] * 256 for kguess in range(0, 256):  # Initialize arrays &amp; variables to zero sumnum = np.zeros(numpoint) sumden1 = np.zeros(numpoint) sumden2 = np.zeros(numpoint)  hyp = np.zeros(numtraces) for tnum in range(0, numtraces): hyp[tnum] = HW[intermediate(pt[tnum][bnum], kguess)]  # Mean of hypothesis meanh = np.mean(hyp, dtype=np.float64)  # Mean of all points in trace meant = np.mean(traces, axis=0, dtype=np.float64)  # For each trace, do the following for tnum in range(0, numtraces): hdiff = (hyp[tnum] -generated by meanh) tdiff = traces[tnum, :] - meant  sumnum = sumnum + (hdiff * tdiff) sumden1 = sumden1 + hdiff * hdiff sumden2 = sumden2 + tdiff * tdiff  cpaoutput[kguess] = sumnum / np.sqrt(sumden1 * sumden2) maxcpa[kguess] = max(abs(cpaoutput[kguess]))  bestguess[bnum] = np.argmax(maxcpa)  cparefs = np.argsort(maxcpa)[::-1]  # Find PGE pge[bnum] = list(cparefs).index(knownkey[bnum]) print("Best Key Guess: ", end="")for b in bestguess: print("%02x " % b, end="") print("")print("PGE: ", end="")for b in pge: print("%02d " % b, end="")</syntaxhighlight> === Exploring glitches ===This script shows an example of using the analyzer ChipWhisperer tool for performing clock glitch attacks on a target executing code. This script has similar functionality of the glitch explorer in the GUI but exposes more the insides of the ChipWhisperer tool. This script varies the offset and the width percentage of the clock glitch applied to the target during code execution. More details about clock glitching can also be used standalone or saved found in [[Tutorial_A2_Introduction_to_Glitch_Attacks_(including_Glitch_Explorer) | Tutorial A2]] ==== XMEGA Target ====<syntaxhighlight lang=python>from __future__ import print_function, division import timeimport loggingimport osfrom collections import namedtupleimport csv import numpy as np import chipwhisperer as cwfrom chipwhisperer.tests.tools_for_tests import FIRMWARE_DIRfrom chipwhisperer.capture.api.programmers import XMEGAProgrammer#from scripting_utils import GlitchResultsDisplay logging.basicConfig(level=logging.WARN)scope = cw.scope()target = cw.target(scope) # setup parameters needed for glitch the scripts directory so XMEGAscope.glitch.clk_src = 'clkgen' scope.gain.gain = 45scope.adc.samples = 3000scope.adc.offset = 0scope.adc.basic_mode = "rising_edge"scope.clock.clkgen_freq = 7370000scope.clock.adc_src = "clkgen_x4"scope.trigger.triggers = "tio4"scope.io.tio1 = "serial_rx"scope.io.tio2 = "serial_tx"scope.io.hs2 = "glitch" target.go_cmd = ""target.key_cmd = "" # program the XMEGA with the built hex fileprogrammer = XMEGAProgrammer()programmer.scope = scopeprogrammer._logging = Noneprogrammer.find()programmer.erase()glitch_simple_firmware_dir = os.path.join(FIRMWARE_DIR, 'glitch-simple')glitch_simple_hex = os.path.join(glitch_simple_firmware_dir, r"glitchsimple-CW303.hex")programmer.program(glitch_simple_hex, memtype="flash", verify=True)programmer.close() # format output tableheaders = ['target output', 'width', 'offset', 'success']#glitch_display = GlitchResultsDisplay(headers) # set glitch parameters# trigger glitches with external triggerscope.glitch.trigger_src = 'ext_single'scope.glitch.repeat = 105 traces = []outputs = []widths = []offsets = [] # named tuples to make it will show up easier to change the scope of the testRange = namedtuple('Range', ['min', 'max', 'step'])width_range = Range(-10, 10, 4)offset_range = Range(-10, 10, 4) # glitch cyclescope.glitch.width = width_range.minopen('glitch_out.csv', 'w').close()f = open('glitch_out.csv', 'ab')writer = csv.writer(f)target.init()while scope.glitch.width < width_range.max: scope.glitch.offset = offset_range.min while scope.glitch.offset < offset_range.max: # call before trace things here  # flush the garbage from the computer's target read buffer target.ser.flush()  # target enters reset mode scope.io.pdic = 'low'  # run aux stuff that should run before the scope arms here  scope.arm()  # run aux stuff that should run after the scope arms here  # target exits reset mode scope.io.pdic = 'high'  timeout = 50 # wait for target to finish while target.isDone() is False and timeout: timeout -= 1 time.sleep(0.01)  try: ret = scope.capture() if ret: logging.warning('Timeout happened during acquisition') except IOError as e: logging.error('IOError: %s' % str(e))  # get the results from the scope trace = scope.getLastTrace() # read from the targets buffer output = target.ser.read(32, timeout=10) traces.append(trace) outputs.append(output) widths.append(scope.glitch.width) offsets.append(scope.glitch.width)  # for table display purposes success = '1234' in repr(output) # check for glitch success (depends on targets active firmware) data = [repr(output), scope.glitch.width, scope.glitch.offset, success] #glitch_display.add_data(data) writer.writerow(data)  # run aux stuff that should happen after trace here scope.glitch.offset += offset_range.step scope.glitch.width += width_range.stepf.close()traces = np.asarray(traces)# the next rest of the data is available with the outputs, widths, and offsets lists#glitch_display.display_table()print('Done') # clean up the connection to the scope and targetscope.dis()target.dis()</syntaxhighlight> ==== STM32F3 Target ====<syntaxhighlight lang=python>from __future__ import print_function, division import timeimport loggingimport osfrom collections import namedtupleimport csv import numpy as np import chipwhisperer as cwfrom chipwhisperer.tests.tools_for_tests import FIRMWARE_DIRfrom chipwhisperer.capture.api.programmers import STM32FProgrammerfrom scripting_utils import GlitchResultsDisplay logging.basicConfig(level=logging.WARN)scope = cw.scope()target = cw.target(scope) # setup parameters needed for glitch the stm32fscope.glitch.clk_src = 'clkgen' scope.gain.gain = 45scope.adc.samples = 5000scope.adc.offset = 0scope.adc.basic_mode = "rising_edge"scope.clock.clkgen_freq = 7370000scope.clock.adc_src = "clkgen_x4"scope.trigger.triggers = "tio4"scope.io.tio1 = "serial_rx"scope.io.tio2 = "serial_tx"scope.io.hs2 = "glitch" target.go_cmd = ""target.key_cmd = "" # program the stm32f with the built hex fileprogrammer = STM32FProgrammer()programmer.scope = scopeprogrammer._logging = Noneprogrammer.open()programmer.find()programmer.erase()glitch_simple_firmware_dir = os.path.join(FIRMWARE_DIR, 'glitch-simple')glitch_simple_hex = os.path.join(glitch_simple_firmware_dir, r"glitchsimple-CW308_STM32F3.hex")programmer.program(glitch_simple_hex, memtype="flash", verify=True)programmer.close() # format output tableheaders = ['target output', 'width', 'offset', 'success']glitch_display = GlitchResultsDisplay(headers) # set glitch parameters# trigger glitches with external triggerscope.glitch.trigger_src = 'ext_single'scope.glitch.repeat = 105 traces = []outputs = []widths = []offsets = [] # named tuples to make it easier to change the scope of the testRange = namedtuple('Range', ['min', 'max', 'step'])width_range = Range(-40, 40, 0.39*5)offset_range = Range(-40, 40, 0.39*5) # glitch cyclescope.glitch.width = width_range.minopen('glitch_out.csv', 'w').close()f = open('glitch_out.csv', 'ab')writer = csv.writer(f)target.init()while scope.glitch.width < width_range.max: scope.glitch.offset = offset_range.min while scope.glitch.offset < offset_range.max: # call before trace things here  # flush the garbage from the computer's target read buffer target.ser.flush()  # run aux stuff that should run before the scope arms here  # target enters reset state scope.io.nrst = 'low'  scope.arm()  # run aux stuff that should run after the scope arms here  # target exits reset state and starts execution scope.io.nrst = 'high'  timeout = 50 # wait for target to finish while target.isDone() is False and timeout: timeout -= 1 time.sleep(0.01)  try: ret = scope.capture() if ret: logging.warning('Timeout happened during acquisition') except IOError as e: logging.error('IOError: %s' % str(e))  # get the results from the scope trace = scope.getLastTrace() # read from the targets buffer output = target.ser.read(32, timeout=100) traces.append(trace) outputs.append(output) widths.append(scope.glitch.width) offsets.append(scope.glitch.width)  # for table display purposes success = '1234' in repr(output) # check for glitch success (depends on targets active firmware) data = [repr(output), scope.glitch.width, scope.glitch.offset, success] glitch_display.add_data(data) writer.writerow(data)  # run aux stuff that should happen after trace here scope.glitch.offset += offset_range.step scope.glitch.width += width_range.stepf.close()traces = np.asarray(traces)# the rest of the data is available with the outputs, widths, and offsets listsglitch_display.display_table()print('Done')</syntaxhighlight>