| # Copyright (c) 2011 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 Python library to interact with TPM module for testing. |
| |
| Background |
| - TPM stands for Trusted Platform Module, a piece of security device |
| - TPM specification is the work of Trusted Computing Group |
| - As of September 2011, the current TPM specification is version 1.2 |
| |
| Dependency |
| - This library depends on a C shared library called "libtspi.so", which |
| contains a set of APIs for interacting with TPM module |
| |
| Notes: |
| - An exception is raised if it doesn't make logical sense to continue program |
| flow (e.g. I/O error prevents test case from executing) |
| - An exception is caught and then converted to an error code if the caller |
| expects to check for error code per API definition |
| """ |
| |
| import datetime, logging |
| |
| from autotest_lib.client.common_lib import smogcheck_ttci |
| # Use explicit import to make code more readable |
| from ctypes import c_uint, c_uint32, cdll, c_bool, Structure, POINTER, \ |
| c_ubyte, c_byte, byref, c_uint16, cast, create_string_buffer, c_uint64, \ |
| c_char_p, addressof, c_char, pointer |
| |
| # TPM flags |
| # TODO(tgao): possible to import from trousers/src/include/tss/tss_defines.h? |
| TSS_KEY_AUTHORIZATION = c_uint32(0x00000001) |
| TSS_KEY_TSP_SRK = c_uint32(0x04000000) |
| TSS_POLICY_USAGE = c_uint32(0x00000001) |
| TSS_OBJECT_TYPE_RSAKEY = c_uint(0x02) |
| TSS_SECRET_MODE_SHA1 = c_uint32(0x00001000) |
| TSS_SECRET_MODE_PLAIN = c_uint32(0x00001800) |
| TSS_TPMCAP_PROP_MANUFACTURER = c_uint(0x12) |
| TSS_TPMCAP_PROPERTY = c_uint(0x13) |
| TSS_TPMCAP_VERSION = c_uint(0x14) |
| TSS_TPMCAP_VERSION_VAL = c_uint32(0x15) |
| TSS_TPMSTATUS_DISABLEOWNERCLEAR = c_uint32(0x00000001) |
| TSS_TPMSTATUS_DISABLEFORCECLEAR = c_uint32(0x00000002) |
| TSS_TPMSTATUS_PHYSICALSETDEACTIVATED = c_uint32(0x00000010) |
| TSS_TPMSTATUS_SETTEMPDEACTIVATED = c_uint32(0x00000011) |
| |
| # TODO(tgao): possible to import from trousers/src/include/tss/tpm.h? |
| TPM_SHA1_160_HASH_LEN = c_uint(0x14) |
| |
| # Path to TSPI shared library. |
| TSPI_C_LIB = "/usr/lib/libtspi.so.1" |
| |
| # Valid operation of tpmSetActive(). Equivalent CLI commands: |
| # 'status' = tpm_setactive --well-known --status |
| # 'activate' = tpm_setactive --well-known --active |
| # 'deactivate' = tpm_setactive --well-known --inactive |
| # 'temp' = tpm_setactive --well-known --temp |
| TPM_SETACTIVE_OP = ['status', 'activate', 'deactivate', 'temp'] |
| |
| # Valid operation of tpmSetClearable(). Equivalent CLI commands: |
| # 'status' = tpm_setclearable --well-known --status |
| # 'owner' = tpm_setclearable --well-known --owner |
| # 'force' = tpm_setclearable --well-known --force |
| TPM_SETCLEARABLE_OP = ['status', 'owner', 'force'] |
| |
| # Secret mode for setPolicySecret() |
| TSS_SECRET_MODE = dict(sha1=TSS_SECRET_MODE_SHA1, |
| plain=TSS_SECRET_MODE_PLAIN) |
| |
| |
| class SmogcheckError(Exception): |
| """Base class for all smogcheck API errors.""" |
| |
| |
| class TpmVersion(Structure): |
| """Defines TPM version string struct. |
| |
| Declared in tss/tpm.h and named TPM_VERSION. |
| """ |
| _fields_ = [('major', c_ubyte), |
| ('minor', c_ubyte), |
| ('revMajor', c_ubyte), |
| ('revMinor', c_ubyte)] |
| |
| |
| class TpmCapVersionInfo(Structure): |
| """Defines TPM version info struct. |
| |
| Declared in tss/tpm.h and named TPM_CAP_VERSION_INFO. |
| """ |
| _fields_ = [('tag', c_uint16), |
| ('version', TpmVersion), |
| ('specLevel', c_uint16), |
| ('errataRev', c_ubyte), |
| ('tpmVendorID', c_char*4), |
| ('vendorSpecific', POINTER(c_ubyte))] |
| |
| |
| def InitVersionInfo(vi): |
| """Utility method to allocate memory for TPM version info. |
| |
| Args: |
| vi: a TpmCapVerisonInfo object, just created. |
| """ |
| vi.tpmVendorId = create_string_buffer(4) # Allocate 4 bytes |
| vendorDetail = create_string_buffer(64) # Allocate 64 bytes |
| vi.vendorSpecific = cast(pointer(vendorDetail), POINTER(c_ubyte)) |
| |
| |
| def PrintVersionInfo(vi): |
| """Utility method to print TPM version info. |
| |
| Args: |
| vi: a TpmCapVerisonInfo object. |
| """ |
| logging.info(' TPM 1.2 Version Info:\n') |
| logging.info(' Chip Version: %d.%d.%d.%d.', vi.version.major, |
| vi.version.minor, vi.version.revMajor, vi.version.revMinor) |
| logging.info(' Spec Level: %d', vi.specLevel) |
| logging.info(' Errata Revision: %d', vi.errataRev) |
| vendorId = [i for i in vi.tpmVendorID if i] |
| logging.info(' TPM Vendor ID: %s', ''.join(vendorId)) |
| # TODO(tgao): handle the case when there's no vendor specific data. |
| logging.info(' Vendor Specific data (first 4 bytes in Hex): ' |
| '%.2x %.2x %.2x %.2x', vi.vendorSpecific[0], |
| vi.vendorSpecific[1], vi.vendorSpecific[2], |
| vi.vendorSpecific[3]) |
| |
| |
| def PrintSelfTestResult(str_len, pResult): |
| """Utility method to print TPM self test result. |
| |
| Args: |
| str_len: an integer, length of string pointed to by pResult. |
| pResult: a c_char_p, pointer to result. |
| """ |
| out = [] |
| for i in range(str_len): |
| if i and not i % 32: |
| out.append('\t') |
| if not i % 4: |
| out.append(' ') |
| b = pResult.value[i] |
| out.append('%02x' % ord(b)) |
| logging.info(' TPM Test Results: %s', ''.join(out)) |
| |
| |
| class TpmController(object): |
| """Object to interact with TPM module for testing.""" |
| |
| def __init__(self): |
| """Constructor. |
| |
| Mandatory params: |
| hContext: a c_uint32, context object handle. |
| _contextSet: a boolean, True if TPM context is set. |
| hTpm: a c_uint32, TPM object handle. |
| hTpmPolicy: a c_uint32, TPM policy object handle. |
| tspi_lib: a shared library object (libtspi.so). |
| |
| Raises: |
| SmogcheckError: if error initializing TpmController. |
| """ |
| self.hContext = c_uint32(0) |
| self._contextSet = False |
| self.hTpm = c_uint32(0) |
| self.hTpmPolicy = c_uint32(0) |
| |
| logging.info('Attempt to load shared library %s', TSPI_C_LIB) |
| try: |
| self.tspi_lib = cdll.LoadLibrary(TSPI_C_LIB) |
| except OSError, e: |
| raise SmogcheckError('Error loading C library %s: %r' % |
| (TSPI_C_LIB, e)) |
| logging.info('Successfully loaded shared library %s', TSPI_C_LIB) |
| |
| def closeContext(self): |
| """Closes TPM context and cleans up. |
| |
| Returns: |
| an integer, 0 for success and -1 for error. |
| """ |
| if not self._contextSet: |
| logging.debug('TPM context NOT set.') |
| return 0 |
| |
| ret = -1 |
| # Calling the pointer type without an argument creates a NULL pointer |
| if self.tspi_lib.Tspi_Context_FreeMemory(self.hContext, |
| POINTER(c_byte)()) != 0: |
| logging.error('Error freeing memory when closing TPM context') |
| else: |
| logging.debug('Tspi_Context_FreeMemory() success') |
| |
| if self.tspi_lib.Tspi_Context_Close(self.hContext) != 0: |
| logging.error('Error closing TPM context') |
| else: |
| logging.debug('Tspi_Context_Close() success') |
| ret = 0 |
| self._contextSet = False |
| |
| return ret |
| |
| def _closeContextObject(self, hObject): |
| """Closes TPM context object. |
| |
| Args: |
| hObject: an integer, basic object handle. |
| |
| Raises: |
| SmogcheckError: if an error is encountered. |
| """ |
| if self.tspi_lib.Tspi_Context_CloseObject(self.hContext, hObject) != 0: |
| raise SmogcheckError('Error closing TPM context object') |
| |
| logging.debug('Tspi_Context_CloseObject() success') |
| |
| def setupContext(self): |
| """Sets up tspi context for TPM access. |
| |
| TPM context cannot be reused. Therefore, each new Tspi_* command would |
| require a new context to be set up before execution and closing that |
| context after execution (or error). |
| |
| Raises: |
| SmogcheckError: if an error is encountered. |
| """ |
| if self._contextSet: |
| logging.debug('TPM context already set.') |
| return |
| |
| if self.tspi_lib.Tspi_Context_Create(byref(self.hContext)) != 0: |
| raise SmogcheckError('Error creating tspi context') |
| |
| logging.info('Created tspi context = 0x%x', self.hContext.value) |
| |
| if self.tspi_lib.Tspi_Context_Connect(self.hContext, |
| POINTER(c_uint16)()) != 0: |
| raise SmogcheckError('Error connecting to tspi context') |
| |
| logging.info('Connected to tspi context') |
| |
| if self.tspi_lib.Tspi_Context_GetTpmObject(self.hContext, |
| byref(self.hTpm)) != 0: |
| raise SmogcheckError('Error getting TPM object from tspi context') |
| |
| logging.info('Got tpm object from tspi context = 0x%x', self.hTpm.value) |
| self._contextSet = True |
| |
| def _getTpmStatus(self, flag, bValue): |
| """Wrapper function to call Tspi_TPM_GetStatus(). |
| |
| Args: |
| flag: a c_uint, TPM status info flag, values defined in C header file |
| "tss/tss_defines.h". |
| bValue: a c_bool, place holder for specific TPM flag bit value (0/1). |
| |
| Raises: |
| SmogcheckError: if an error is encountered. |
| """ |
| result = self.tspi_lib.Tspi_TPM_GetStatus(self.hTpm, flag, |
| byref(bValue)) |
| if result != 0: |
| msg = ('Error (0x%x) getting status for flag 0x%x' % |
| (result, flag.value)) |
| raise SmogcheckError(msg) |
| |
| logging.info('Tspi_TPM_GetStatus(): success for flag 0x%x', |
| flag.value) |
| |
| def _setTpmStatus(self, flag, bValue): |
| """Wrapper function to call Tspi_TPM_GetStatus(). |
| |
| Args: |
| flag: a c_uint, TPM status info flag. |
| bValue: a c_bool, place holder for specific TPM flag bit value (0/1). |
| |
| Raises: |
| SmogcheckError: if an error is encountered. |
| """ |
| result = self.tspi_lib.Tspi_TPM_SetStatus(self.hTpm, flag, bValue) |
| if result != 0: |
| msg = ('Error (0x%x) setting status for flag 0x%x' % |
| (result, flag.value)) |
| raise SmogcheckError(msg) |
| |
| logging.info('Tspi_TPM_SetStatus(): success for flag 0x%x', |
| flag.value) |
| |
| def getPolicyObject(self, hTpm=None, hPolicy=None): |
| """Get TPM policy object. |
| |
| Args: |
| hTpm: a c_uint, TPM object handle. |
| hPolicy: a c_uint, TPM policy object handle. |
| |
| Raises: |
| SmogcheckError: if an error is encountered. |
| """ |
| if hTpm is None: |
| hTpm = self.hTpm |
| |
| if hPolicy is None: |
| hPolicy = self.hTpmPolicy |
| |
| logging.debug('Tspi_GetPolicyObject(): hTpm = 0x%x, hPolicy = 0x%x', |
| hTpm.value, hPolicy.value) |
| result = self.tspi_lib.Tspi_GetPolicyObject(hTpm, TSS_POLICY_USAGE, |
| byref(hPolicy)) |
| if result != 0: |
| msg = 'Error (0x%x) getting TPM policy object' % result |
| raise SmogcheckError(msg) |
| |
| logging.debug('Tspi_GetPolicyObject() success hTpm = 0x%x, ' |
| 'hPolicy = 0x%x', hTpm.value, hPolicy.value) |
| |
| def setPolicySecret(self, hPolicy=None, pSecret=None, secret_mode=None): |
| """Sets TPM policy secret. |
| |
| Args: |
| hPolicy: a c_uint, TPM policy object handle. |
| pSecret: a pointer to a byte array, which holds the TSS secret. |
| secret_mode: a string, valid values are keys of TSS_SECRET_MODE. |
| |
| Raises: |
| SmogcheckError: if an error is encountered. |
| """ |
| if hPolicy is None: |
| hPolicy = self.hTpmPolicy |
| |
| if pSecret is None: |
| raise SmogcheckError('setPolicySecret(): pSecret cannot be None') |
| |
| if secret_mode is None or secret_mode not in TSS_SECRET_MODE: |
| raise SmogcheckError('setPolicySecret(): invalid secret_mode') |
| |
| logging.debug('Tspi_Policy_SetSecret(): hPolicy = 0x%x, secret_mode ' |
| '(%r) = %r', hPolicy.value, secret_mode, |
| TSS_SECRET_MODE[secret_mode]) |
| |
| result = self.tspi_lib.Tspi_Policy_SetSecret( |
| hPolicy, TSS_SECRET_MODE[secret_mode], TPM_SHA1_160_HASH_LEN, |
| pSecret) |
| if result != 0: |
| msg = 'Error (0x%x) setting TPM policy secret' % result |
| raise SmogcheckError(msg) |
| |
| logging.debug('Tspi_Policy_SetSecret() success, hPolicy = 0x%x', |
| hPolicy.value) |
| |
| def getTpmVersion(self): |
| """Gets TPM version info. |
| |
| Implementation based on tpm-tools-1.3.4/src/tpm_mgmt/tpm_version.c |
| Downloaded from: |
| http://sourceforge.net/projects/trousers/files/tpm-tools/1.3.4/\ |
| tpm-tools-1.3.4.tar.gz |
| |
| Raises: |
| SmogcheckError: if an error is encountered. |
| """ |
| uiResultLen = c_uint32(0) |
| pResult = c_char_p() |
| offset = c_uint64(0) |
| versionInfo = TpmCapVersionInfo() |
| InitVersionInfo(versionInfo) |
| |
| logging.debug('Successfully set up tspi context: hTpm = %r', self.hTpm) |
| |
| result = self.tspi_lib.Tspi_TPM_GetCapability( |
| self.hTpm, TSS_TPMCAP_VERSION_VAL, 0, POINTER(c_byte)(), |
| byref(uiResultLen), byref(pResult)) |
| if result != 0: |
| msg = 'Error (0x%x) getting TPM capability, pResult = %r' % ( |
| result, pResult.value) |
| raise SmogcheckError(msg) |
| |
| logging.info('Successfully received TPM capability: ' |
| 'uiResultLen = %d, pResult=%r', uiResultLen.value, |
| pResult.value) |
| result = self.tspi_lib.Trspi_UnloadBlob_CAP_VERSION_INFO( |
| byref(offset), pResult, cast(byref(versionInfo), |
| POINTER(c_byte))) |
| if result != 0: |
| msg = 'Error (0x%x) unloading TPM CAP version info' % result |
| raise SmogcheckError(msg) |
| |
| PrintVersionInfo(versionInfo) |
| |
| def runTpmSelfTest(self): |
| """Executes TPM self test. |
| |
| Implementation based on tpm-tools-1.3.4/src/tpm_mgmt/tpm_selftest.c |
| |
| Raises: |
| SmogcheckError: if an error is encountered. |
| """ |
| uiResultLen = c_uint32(0) |
| pResult = c_char_p() |
| self.setupContext() |
| |
| logging.debug('Successfully set up tspi context: hTpm = 0x%x', |
| self.hTpm.value) |
| |
| result = self.tspi_lib.Tspi_TPM_SelfTestFull(self.hTpm) |
| if result != 0: |
| self.closeContext() |
| raise SmogcheckError('Error (0x%x) with TPM self test' % result) |
| |
| logging.info('Successfully executed TPM self test: hTpm = 0x%x', |
| self.hTpm.value) |
| result = self.tspi_lib.Tspi_TPM_GetTestResult( |
| self.hTpm, byref(uiResultLen), byref(pResult)) |
| if result != 0: |
| self.closeContext() |
| raise SmogcheckError('Error (0x%x) getting test results' % result) |
| |
| logging.info('TPM self test results: uiResultLen = %d, pResult=%r', |
| uiResultLen.value, pResult.value) |
| PrintSelfTestResult(uiResultLen.value, pResult) |
| self.closeContext() |
| |
| def takeTpmOwnership(self): |
| """Take TPM ownership. |
| |
| Implementation based on tpm-tools-1.3.4/src/tpm_mgmt/tpm_takeownership.c |
| |
| Raises: |
| SmogcheckError: if an error is encountered. |
| """ |
| hSrk = c_uint32(0) # TPM Storage Root Key |
| hSrkPolicy = c_uint32(0) |
| # Defaults each byte value to 0x00 |
| well_known_secret = create_string_buffer(20) |
| pSecret = c_char_p(addressof(well_known_secret)) |
| |
| self.setupContext() |
| logging.debug('Successfully set up tspi context: hTpm = 0x%x', |
| self.hTpm.value) |
| |
| try: |
| self.getPolicyObject() |
| self.setPolicySecret(pSecret=pSecret, secret_mode='sha1') |
| except SmogcheckError: |
| if hSrk != 0: |
| self._closeContextObject(hSrk) |
| self.closeContext() |
| raise # re-raise |
| |
| flag = TSS_KEY_TSP_SRK.value | TSS_KEY_AUTHORIZATION.value |
| result = self.tspi_lib.Tspi_Context_CreateObject( |
| self.hContext, TSS_OBJECT_TYPE_RSAKEY, flag, byref(hSrk)) |
| if result != 0: |
| raise SmogcheckError('Error (0x%x) creating context object' % |
| result) |
| logging.debug('hTpm = 0x%x, flag = 0x%x, hSrk = 0x%x', |
| self.hTpm.value, flag, hSrk.value) # DEBUG |
| |
| try: |
| self.getPolicyObject(hTpm=hSrk, hPolicy=hSrkPolicy) |
| self.setPolicySecret(hPolicy=hSrkPolicy, pSecret=pSecret, |
| secret_mode='sha1') |
| except SmogcheckError: |
| if hSrk != 0: |
| self._closeContextObject(hSrk) |
| self.closeContext() |
| raise # re-raise |
| |
| logging.debug('Successfully set up SRK policy: secret = %r, ' |
| 'hSrk = 0x%x, hSrkPolicy = 0x%x', |
| well_known_secret.value, hSrk.value, hSrkPolicy.value) |
| |
| start_time = datetime.datetime.now() |
| result = self.tspi_lib.Tspi_TPM_TakeOwnership(self.hTpm, hSrk, |
| c_uint(0)) |
| end_time = datetime.datetime.now() |
| if result != 0: |
| logging.info('Tspi_TPM_TakeOwnership error') |
| self._closeContextObject(hSrk) |
| self.closeContext() |
| raise SmogcheckError('Error (0x%x) taking TPM ownership' % result) |
| |
| logging.info('Successfully took TPM ownership') |
| self._closeContextObject(hSrk) |
| self.closeContext() |
| return smogcheck_ttci.computeTimeElapsed(end_time, start_time) |
| |
| def clearTpm(self): |
| """Return TPM to default state. |
| |
| Implementation based on tpm-tools-1.3.4/src/tpm_mgmt/tpm_clear.c |
| |
| Raises: |
| SmogcheckError: if an error is encountered. |
| """ |
| logging.debug('Successfully set up tspi context: hTpm = %r', self.hTpm) |
| |
| result = self.tspi_lib.Tspi_TPM_ClearOwner(self.hTpm, True) |
| if result != 0: |
| raise SmogcheckError('Error (0x%x) clearing TPM' % result) |
| |
| logging.info('Successfully cleared TPM') |
| |
| def setTpmActive(self, op): |
| """Change TPM active state. |
| |
| Implementation based on tpm-tools-1.3.4/src/tpm_mgmt/tpm_activate.c |
| |
| Args: |
| op: a string, desired operation. Valid values are defined in |
| TPM_SETACTIVE_OP. |
| |
| Raises: |
| SmogcheckError: if an error is encountered. |
| """ |
| bValue = c_bool() |
| # Defaults each byte value to 0x00 |
| well_known_secret = create_string_buffer(20) |
| pSecret = c_char_p(addressof(well_known_secret)) |
| |
| if op not in TPM_SETACTIVE_OP: |
| msg = ('Invalid op (%s) for tpmSetActive(). Valid values are %r' % |
| (op, TPM_SETACTIVE_OP)) |
| raise SmogcheckError(msg) |
| |
| logging.debug('Successfully set up tspi context: hTpm = %r', self.hTpm) |
| |
| if op == 'status': |
| self.getPolicyObject() |
| self.setPolicySecret(pSecret=pSecret, secret_mode='sha1') |
| |
| self._getTpmStatus( |
| TSS_TPMSTATUS_PHYSICALSETDEACTIVATED, bValue) |
| logging.info('Persistent Deactivated Status: %s', bValue.value) |
| |
| self._getTpmStatus( |
| TSS_TPMSTATUS_SETTEMPDEACTIVATED, bValue) |
| logging.info('Volatile Deactivated Status: %s', bValue.value) |
| elif op == 'activate': |
| self._setTpmStatus( |
| TSS_TPMSTATUS_PHYSICALSETDEACTIVATED, False) |
| logging.info('Successfully activated TPM') |
| elif op == 'deactivate': |
| self._setTpmStatus( |
| TSS_TPMSTATUS_PHYSICALSETDEACTIVATED, True) |
| logging.info('Successfully deactivated TPM') |
| elif op == 'temp': |
| self._setTpmStatus( |
| TSS_TPMSTATUS_SETTEMPDEACTIVATED, True) |
| logging.info('Successfully deactivated TPM for current boot') |
| |
| def setTpmClearable(self, op): |
| """Disable TPM clear operations. |
| |
| Implementation based on tpm-tools-1.3.4/src/tpm_mgmt/tpm_clearable.c |
| |
| Args: |
| op: a string, desired operation. Valid values are defined in |
| TPM_SETCLEARABLE_OP. |
| |
| Raises: |
| SmogcheckError: if an error is encountered. |
| """ |
| bValue = c_bool() |
| # Defaults each byte value to 0x00 |
| well_known_secret = create_string_buffer(20) |
| pSecret = c_char_p(addressof(well_known_secret)) |
| |
| if op not in TPM_SETCLEARABLE_OP: |
| msg = ('Invalid op (%s) for tpmSetClearable(). Valid values are %r' |
| % (op, TPM_SETCLEARABLE_OP)) |
| raise SmogcheckError(msg) |
| |
| logging.debug('Successfully set up tspi context: hTpm = %r', self.hTpm) |
| |
| if op == 'status': |
| self.getPolicyObject() |
| self.setPolicySecret(pSecret=pSecret, secret_mode='sha1') |
| |
| self._getTpmStatus( |
| TSS_TPMSTATUS_DISABLEOWNERCLEAR, bValue) |
| logging.info('Owner Clear Disabled: %s', bValue.value) |
| |
| self._getTpmStatus( |
| TSS_TPMSTATUS_DISABLEFORCECLEAR, bValue) |
| logging.info('Force Clear Disabled: %s', bValue.value) |
| elif op == 'owner': |
| self.getPolicyObject() |
| self.setPolicySecret(pSecret=pSecret, secret_mode='sha1') |
| |
| self._setTpmStatus( |
| TSS_TPMSTATUS_DISABLEOWNERCLEAR, False) |
| logging.info('Successfully disabled Owner Clear') |
| elif op == 'force': |
| self._setTpmStatus( |
| TSS_TPMSTATUS_DISABLEFORCECLEAR, True) |
| logging.info('Successfully disabled Force Clear') |