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brentru
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add code, up to network setup, ported to pyportal
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‎PyPortal_TOTP_Friend/code.py‎

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import time
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import board
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import busio
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from digitalio import DigitalInOut
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from adafruit_esp32spi import adafruit_esp32spi
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from adafruit_ntp import NTP
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import adafruit_hashlib as hashlib
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from adafruit_binascii import hexlify, unhexlify
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# https://github.com/pyotp/pyotp example
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totp = [("Discord ", 'JBSWY3DPEHPK3PXP'),
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("Gmail ", 'abcdefghijklmnopqrstuvwxyz234567'),
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("Accounts", 'asfdkwefoaiwejfa323nfjkl')]
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ssid = 'my_wifi_ssid'
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password = 'my_wifi_password'
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TEST = True # if you want to print out the tests the hashers
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ALWAYS_ON = False # Set to true if you never want to go to sleep!
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ON_SECONDS = 60 # how long to stay on if not in always_on mode
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EPOCH_DELTA = 946684800 # seconds between year 2000 and year 1970
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SECS_DAY = 86400
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# Create a SHA1 Object
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SHA1 = hashlib.sha1
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if TEST:
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print("===========================================")
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sha1_output = hexlify(SHA1(b'hello world').digest())
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assert sha1_output == b"2aae6c35c94fcfb415dbe95f408b9ce91ee846ed"
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# HMAC implementation, as hashlib/hmac wouldn't fit
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# From https://en.wikipedia.org/wiki/Hash-based_message_authentication_code
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def HMAC(k, m):
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SHA1_BLOCK_SIZE = 64
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KEY_BLOCK = k + (b'\0' * (SHA1_BLOCK_SIZE - len(k)))
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KEY_INNER = bytes((x ^ 0x36) for x in KEY_BLOCK)
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KEY_OUTER = bytes((x ^ 0x5C) for x in KEY_BLOCK)
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inner_message = KEY_INNER + m
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outer_message = KEY_OUTER + SHA1(inner_message).digest()
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return SHA1(outer_message)
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if TEST:
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KEY = b'abcd'
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MESSAGE = b'efgh'
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print("===========================================")
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hmac_out = hexlify(HMAC(KEY, MESSAGE).digest())
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assert hmac_out == b'e5dbcf9263188f9fce90df572afeb39b66b27198'
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def base32_decode(encoded):
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missing_padding = len(encoded) % 8
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if missing_padding != 0:
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encoded += '=' * (8 - missing_padding)
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encoded = encoded.upper()
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chunks = [encoded[i:i + 8] for i in range(0, len(encoded), 8)]
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out = []
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for chunk in chunks:
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bits = 0
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bitbuff = 0
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for c in chunk:
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if 'A' <= c <= 'Z':
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n = ord(c) - ord('A')
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elif '2' <= c <= '7':
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n = ord(c) - ord('2') + 26
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elif n == '=':
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continue
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else:
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raise ValueError("Not base32")
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# 5 bits per 8 chars of base32
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bits += 5
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# shift down and add the current value
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bitbuff <<= 5
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bitbuff |= n
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# great! we have enough to extract a byte
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if bits >= 8:
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bits -= 8
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byte = bitbuff >> bits # grab top 8 bits
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bitbuff &= ~(0xFF << bits) # and clear them
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out.append(byte) # store what we got
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return out
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if TEST:
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print("===========================================")
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assert (bytes(base32_decode("IFSGCZTSOVUXIIJB")) == b'Adafruit!!')
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def int_to_bytestring(i, padding=8):
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result = []
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while i != 0:
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result.insert(0, i & 0xFF)
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i >>= 8
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result = [0] * (padding - len(result)) + result
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return bytes(result)
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# HMAC -> OTP generator, pretty much same as
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# https://github.com/pyotp/pyotp/blob/master/src/pyotp/otp.py
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def generate_otp(int_input, secret_key, digits=6):
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if int_input < 0:
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raise ValueError('input must be positive integer')
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hmac_hash = bytearray(
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HMAC(bytes(base32_decode(secret_key)),
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int_to_bytestring(int_input)).digest()
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)
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offset = hmac_hash[-1] & 0xf
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code = ((hmac_hash[offset] & 0x7f) << 24 |
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(hmac_hash[offset + 1] & 0xff) << 16 |
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(hmac_hash[offset + 2] & 0xff) << 8 |
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(hmac_hash[offset + 3] & 0xff))
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str_code = str(code % 10 ** digits)
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while len(str_code) < digits:
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str_code = '0' + str_code
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return str_code
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print("===========================================")

‎PyPortal_TOTP_Friend/limor_code.py‎

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import time
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import adafruit_ssd1306
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import bitbangio as io
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import board
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import network
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import ntptime
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import ubinascii
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import uhashlib
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# pylint: disable=broad-except
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# https://github.com/pyotp/pyotp example
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totp = [("Discord ", 'JBSWY3DPEHPK3PXP'),
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("Gmail ", 'abcdefghijklmnopqrstuvwxyz234567'),
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("Accounts", 'asfdkwefoaiwejfa323nfjkl')]
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ssid = 'my_wifi_ssid'
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password = 'my_wifi_password'
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TEST = False # if you want to print out the tests the hashers
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ALWAYS_ON = False # Set to true if you never want to go to sleep!
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ON_SECONDS = 60 # how long to stay on if not in always_on mode
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i2c = io.I2C(board.SCL, board.SDA)
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oled = adafruit_ssd1306.SSD1306_I2C(128, 32, i2c)
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# Gimme a welcome screen!
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oled.fill(0)
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oled.text('CircuitPython', 0, 0)
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oled.text('PyTOTP Pal!', 0, 10)
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oled.text(' <3 adafruit <3 ', 0, 20)
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oled.show()
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time.sleep(0.25)
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EPOCH_DELTA = 946684800 # seconds between year 2000 and year 1970
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SECS_DAY = 86400
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SHA1 = uhashlib.sha1
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if TEST:
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print("===========================================")
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print("SHA1 test: ", ubinascii.hexlify(SHA1(b'hello world').digest()))
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# should be 2aae6c35c94fcfb415dbe95f408b9ce91ee846ed
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# HMAC implementation, as hashlib/hmac wouldn't fit
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# From https://en.wikipedia.org/wiki/Hash-based_message_authentication_code
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def HMAC(k, m):
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SHA1_BLOCK_SIZE = 64
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KEY_BLOCK = k + (b'\0' * (SHA1_BLOCK_SIZE - len(k)))
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KEY_INNER = bytes((x ^ 0x36) for x in KEY_BLOCK)
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KEY_OUTER = bytes((x ^ 0x5C) for x in KEY_BLOCK)
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inner_message = KEY_INNER + m
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outer_message = KEY_OUTER + SHA1(inner_message).digest()
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return SHA1(outer_message)
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if TEST:
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KEY = b'abcd'
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MESSAGE = b'efgh'
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print("===========================================")
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print("HMAC test: ", ubinascii.hexlify(HMAC(KEY, MESSAGE).digest()))
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# should be e5dbcf9263188f9fce90df572afeb39b66b27198
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# Base32 decoder, since base64 lib wouldnt fit
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def base32_decode(encoded):
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missing_padding = len(encoded) % 8
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if missing_padding != 0:
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encoded += '=' * (8 - missing_padding)
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encoded = encoded.upper()
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chunks = [encoded[i:i + 8] for i in range(0, len(encoded), 8)]
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out = []
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for chunk in chunks:
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bits = 0
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bitbuff = 0
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for c in chunk:
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if 'A' <= c <= 'Z':
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n = ord(c) - ord('A')
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elif '2' <= c <= '7':
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n = ord(c) - ord('2') + 26
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elif n == '=':
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continue
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else:
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raise ValueError("Not base32")
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# 5 bits per 8 chars of base32
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bits += 5
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# shift down and add the current value
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bitbuff <<= 5
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bitbuff |= n
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# great! we have enough to extract a byte
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if bits >= 8:
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bits -= 8
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byte = bitbuff >> bits # grab top 8 bits
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bitbuff &= ~(0xFF << bits) # and clear them
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out.append(byte) # store what we got
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return out
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if TEST:
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print("===========================================")
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print("Base32 test: ", bytes(base32_decode("IFSGCZTSOVUXIIJB")))
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# should be "Adafruit!!"
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# Turns an integer into a padded-with-0x0 bytestr
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def int_to_bytestring(i, padding=8):
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result = []
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while i != 0:
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result.insert(0, i & 0xFF)
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i >>= 8
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result = [0] * (padding - len(result)) + result
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return bytes(result)
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# HMAC -> OTP generator, pretty much same as
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# https://github.com/pyotp/pyotp/blob/master/src/pyotp/otp.py
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def generate_otp(int_input, secret_key, digits=6):
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if int_input < 0:
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raise ValueError('input must be positive integer')
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hmac_hash = bytearray(
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HMAC(bytes(base32_decode(secret_key)),
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int_to_bytestring(int_input)).digest()
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)
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offset = hmac_hash[-1] & 0xf
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code = ((hmac_hash[offset] & 0x7f) << 24 |
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(hmac_hash[offset + 1] & 0xff) << 16 |
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(hmac_hash[offset + 2] & 0xff) << 8 |
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(hmac_hash[offset + 3] & 0xff))
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str_code = str(code % 10 ** digits)
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while len(str_code) < digits:
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str_code = '0' + str_code
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return str_code
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print("===========================================")
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# Set up networking
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sta_if = network.WLAN(network.STA_IF)
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oled.fill(0)
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oled.text('Connecting to', 0, 0)
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oled.text(ssid, 0, 10)
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oled.show()
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if not sta_if.isconnected():
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print("Connecting to SSID", ssid)
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sta_if.active(True)
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sta_if.connect(ssid, password)
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while not sta_if.isconnected():
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pass
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print("Connected! IP = ", sta_if.ifconfig()[0])
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# Done! Let them know we made it
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oled.text("IP: " + sta_if.ifconfig()[0], 0, 20)
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oled.show()
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time.sleep(0.25)
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# Get the latest time from NTP
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t = None
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while not t:
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try:
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t = ntptime.time()
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except Exception:
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pass
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time.sleep(0.1)
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# NTP time is seconds-since-2000
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print("NTP time: ", t)
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# But we need Unix time, which is seconds-since-1970
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t += EPOCH_DELTA
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print("Unix time: ", t)
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# Instead of using RTC which means converting back and forth
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# we'll just keep track of seconds-elapsed-since-NTP-call
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mono_time = int(time.monotonic())
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print("Monotonic time", mono_time)
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countdown = ON_SECONDS # how long to stay on if not in always_on mode
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while ALWAYS_ON or (countdown > 0):
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# Calculate current time based on NTP + monotonic
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unix_time = t - mono_time + int(time.monotonic())
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print("Unix time: ", unix_time)
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# Clear the screen
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oled.fill(0)
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y = 0
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# We can do up to 3 per line on the Feather OLED
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for name, secret in totp:
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otp = generate_otp(unix_time // 30, secret)
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print(name + " OTP output: ", otp) # serial debugging output
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oled.text(name + ": " + str(otp), 0, y) # display name & OTP on OLED
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y += 10 # Go to next line on OLED
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# Display a little bar that 'counts down' how many seconds you have left
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oled.framebuf.line(0, 31, 128 - (unix_time % 30) * 4, 31, True)
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oled.show()
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# We'll update every 1/4 second, we can hash very fast so its no biggie!
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countdown -= 0.25
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time.sleep(0.25)
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# All these hashes will be lost in time(), like tears in rain. Time to die
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oled.fill(0)
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oled.show()

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