Changes

{{Warningbox|For the older V3.x tools, see [[V3:Making_Scripts]]}}

TODO== 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>. === Perform Some Traces during AES encryption and get the results as Numpy array ===This script is an example of using the <code>chipwhisperer</code> module for capturing traces during AES encryption. <b>Make sure to have the correct firmware loaded on the target.</b> These traces are then saved and loaded later for analysis. ==== XMEGA 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 XMEGAProgrammer scope = cw.scope()target = cw.target(scope) # setup scope parametersscope.gain.gain = 45scope.adc.samples = 3000scope.adc.offset = 1250scope.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 = XMEGAProgrammer()programmer.scope = scopeprogrammer._logging = Noneprogrammer.find()programmer.erase()aes_firmware_dir = os.path.join(FIRMWARE_DIR, 'simpleserial-aes')aes_hex = os.path.join(aes_firmware_dir, r"simpleserial-aes-CW303.hex")programmer.program(aes_hex, memtype="flash", verify=True)programmer.close() ktp = AcqKeyTextPattern_Basic(target=target) traces = []textin = []keys = []N = 50 # Number of tracestarget.init()for i in tqdm(range(N), desc='Capturing traces'): Push # 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 update scope arms here  scope.arm()  # run aux stuff that should run after the scope arms here  target.go() timeout = 50 # wait for V4target 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() # clears the response from the serial port 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 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(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 tracestarget.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 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(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 all the samept = textinsnumtraces = np.shape(traces)[0]numpoint = 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] - 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 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 be 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 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 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 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.xdisplay_table()print('Done')</syntaxhighlight>