tools/crypto/ccp/dbc.py

   1 #!/usr/bin/python3
   2 # SPDX-License-Identifier: GPL-2.0
   3
   4 import ctypes
   5 import os
   6
   7 DBC_UID_SIZE = 16
   8 DBC_NONCE_SIZE = 16
   9 DBC_SIG_SIZE = 32
  10
  11 PARAM_GET_FMAX_CAP = (0x3,)
  12 PARAM_SET_FMAX_CAP = (0x4,)
  13 PARAM_GET_PWR_CAP = (0x5,)
  14 PARAM_SET_PWR_CAP = (0x6,)
  15 PARAM_GET_GFX_MODE = (0x7,)
  16 PARAM_SET_GFX_MODE = (0x8,)
  17 PARAM_GET_CURR_TEMP = (0x9,)
  18 PARAM_GET_FMAX_MAX = (0xA,)
  19 PARAM_GET_FMAX_MIN = (0xB,)
  20 PARAM_GET_SOC_PWR_MAX = (0xC,)
  21 PARAM_GET_SOC_PWR_MIN = (0xD,)
  22 PARAM_GET_SOC_PWR_CUR = (0xE,)
  23
  24 DEVICE_NODE = "/dev/dbc"
  25
  26 lib = ctypes.CDLL("./dbc_library.so", mode=ctypes.RTLD_GLOBAL)
  27
  28
  29 def handle_error(code):
  30     raise OSError(code, os.strerror(code))
  31
  32
  33 def get_nonce(device, signature):
  34     if not device:
  35         raise ValueError("Device required")
  36     buf = ctypes.create_string_buffer(DBC_NONCE_SIZE)
  37     ret = lib.get_nonce(device.fileno(), ctypes.byref(buf), signature)
  38     if ret:
  39         handle_error(ret)
  40     return buf.value
  41
  42
  43 def set_uid(device, new_uid, signature):
  44     if not signature:
  45         raise ValueError("Signature required")
  46     if not new_uid:
  47         raise ValueError("UID required")
  48     ret = lib.set_uid(device.fileno(), new_uid, signature)
  49     if ret:
  50         handle_error(ret)
  51     return True
  52
  53
  54 def process_param(device, message, signature, data=None):
  55     if not signature:
  56         raise ValueError("Signature required")
  57     if type(message) != tuple:
  58         raise ValueError("Expected message tuple")
  59     arg = ctypes.c_int(data if data else 0)
  60     sig = ctypes.create_string_buffer(signature, len(signature))
  61     ret = lib.process_param(device.fileno(), message[0], ctypes.pointer(sig), ctypes.pointer(arg))
  62     if ret:
  63         handle_error(ret)
  64     return arg.value, sig.value