| # Copyright (c) 2010 The Chromium OS Authors. All rights reserved. |
| # Use of this source code is governed by a BSD-style license that can be |
| # found in the LICENSE file. |
| """A module containing TPM handler class used by SAFT.""" |
| |
| FW_NV_ADDRESS = 0x1007 |
| KERNEL_NV_ADDRESS = 0x1008 |
| |
| |
| class TpmError(Exception): |
| """An object to represent TPM errors""" |
| pass |
| |
| |
| class TpmNvRam(object): |
| """An object representing TPM NvRam. |
| |
| @ivar addr: a number, NvRAm address in TPM. |
| @ivar size: a number, count of bites in this NvRam section. |
| @ivar os_if: an instance of the OS interface (os_interface or a mock object) |
| @ivar version_offset: - a number, offset into the NvRam contents where the |
| the versions are stored. The total version field size is 4 bytes, the |
| first two bytes are the body version, the second two bytes are the key |
| version. Numbers are stored in little endian format. |
| @ivar pattern: optional, a tuple of two elements, the first element is the |
| offset of the pattern expected to be present in the NvRam, and the |
| second element is an array of bytes the pattern must match. |
| @ivar contents: an array of bytes, the contents of the NvRam. |
| @type os_if: autotest_lib.client.cros.faft.utils.os_interface.OSInterface |
| """ |
| |
| def __init__(self, os_if, addr, size, version_offset, data_pattern=None): |
| self.os_if = os_if |
| self.addr = addr |
| self.size = size |
| self.version_offset = version_offset |
| self.pattern = data_pattern |
| self.contents = [] |
| |
| def init(self): |
| """Initialize the object, loading tpm nvram information from the device. |
| """ |
| cmd = 'tpmc read 0x%x 0x%x' % (self.addr, self.size) |
| output = self.os_if.run_shell_command_get_output(cmd) |
| if not output: |
| raise TpmError('Failed to read Nvram') |
| nvram_data = output[0].split() |
| self.contents = [int(x, 16) for x in nvram_data] |
| if self.pattern: |
| pattern_offset = self.pattern[0] |
| pattern_data = self.pattern[1] |
| contents_pattern = self.contents[pattern_offset:pattern_offset + |
| len(pattern_data)] |
| if contents_pattern != pattern_data: |
| raise TpmError('Nvram pattern does not match') |
| |
| def get_body_version(self): |
| return self.contents[self.version_offset + 1] * 256 + self.contents[ |
| self.version_offset] |
| |
| def get_key_version(self): |
| return self.contents[self.version_offset + 3] * 256 + self.contents[ |
| self.version_offset + 2] |
| |
| |
| class TpmNvRamOptions(object): |
| """An object representing a number of potential TPM NvRam objects. |
| |
| @ivar nvrams: A list of TpmNvRam objects. The first TpmNvRam that |
| successfully initializes is selected and used so more specific |
| selectors should be listed earlier. |
| """ |
| |
| def __init__(self, nvrams): |
| self._nvrams = nvrams |
| self._valid_nvram = None |
| |
| def init(self): |
| """Selects a valid TpmNvRam and initializes it.""" |
| for nvram in self._nvrams: |
| try: |
| nvram.init() |
| except TpmError: |
| continue |
| else: |
| self._valid_nvram = nvram |
| break |
| else: |
| raise TpmError('No Nvram pattern matched') |
| |
| def get_body_version(self): |
| return self._valid_nvram.get_body_version() |
| |
| def get_key_version(self): |
| return self._valid_nvram.get_key_version() |
| |
| |
| class TpmHandler(object): |
| """An object to control TPM device's NVRAM. |
| |
| @ivar os_if: an instance of the OS interface (os_interface or a mock object) |
| @ivar nvrams: A dictionary where the keys are nvram names, and the values |
| are instances of TpmNvRam objects, providing access to the |
| appropriate TPM NvRam sections. |
| @ivar tpm_version: Either "1.2" or "2.0". |
| @type os_if: autotest_lib.client.cros.faft.utils.os_interface.OSInterface |
| """ |
| |
| def __init__(self, os_if): |
| self.os_if = os_if |
| self.nvrams = { |
| 'kernel': |
| TpmNvRamOptions([ |
| TpmNvRam( |
| self.os_if, |
| addr=KERNEL_NV_ADDRESS, |
| size=13, |
| version_offset=5, |
| data_pattern=(1, [0x4c, 0x57, 0x52, 0x47])), |
| TpmNvRam( |
| self.os_if, |
| addr=KERNEL_NV_ADDRESS, |
| size=0x28, |
| version_offset=4, |
| data_pattern=(0, [0x10, 0x28])), |
| ]), |
| 'bios': |
| TpmNvRam( |
| self.os_if, |
| addr=FW_NV_ADDRESS, |
| size=10, |
| version_offset=2) |
| } |
| self.tpm_version = None |
| self.trunksd_started = False |
| self.tcsd_started = False |
| self.initialized = False |
| |
| def init(self): |
| """Initialize the values of the nvram sections. |
| |
| This is separate from object creation so it can be done only when a test |
| actually uses it. |
| """ |
| self.stop_daemon() |
| for nvram in self.nvrams.itervalues(): |
| nvram.init() |
| self.restart_daemon() |
| self.initialized = True |
| |
| def get_fw_version(self): |
| return self.nvrams['bios'].get_body_version() |
| |
| def get_fw_key_version(self): |
| return self.nvrams['bios'].get_key_version() |
| |
| def get_kernel_version(self): |
| return self.nvrams['kernel'].get_body_version() |
| |
| def get_kernel_key_version(self): |
| return self.nvrams['kernel'].get_key_version() |
| |
| def get_tpm_version(self): |
| if self.tpm_version is None: |
| self.tpm_version = self.os_if.run_shell_command_get_output( |
| 'tpmc tpmver')[0] |
| return self.tpm_version |
| |
| def stop_daemon(self): |
| """Stop TPM related daemon.""" |
| if self.trunksd_started or self.tcsd_started: |
| raise TpmError('Called stop_daemon() before') |
| |
| cmd = 'initctl status tcsd || initctl status trunksd' |
| status = self.os_if.run_shell_command_get_output(cmd) or [''] |
| # Expected status is like ['trunksd start/running, process 2375'] |
| self.trunksd_started = status[0].startswith('trunksd start/running') |
| if self.trunksd_started: |
| self.os_if.run_shell_command('stop trunksd') |
| else: |
| self.tcsd_started = status[0].startswith('tcsd start/running') |
| if self.tcsd_started: |
| self.os_if.run_shell_command('stop tcsd') |
| |
| def restart_daemon(self): |
| """Restart TPM related daemon which was stopped by stop_daemon().""" |
| if self.trunksd_started: |
| self.os_if.run_shell_command('start trunksd') |
| self.trunksd_started = False |
| elif self.tcsd_started: |
| self.os_if.run_shell_command('start tcsd') |
| self.tcsd_started = False |
