| # Copyright (c) 2012 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. |
| |
| """Utility functions used for PKCS#11 library testing.""" |
| |
| import grp, logging, os, pwd, re, stat, sys, shutil, pwd, grp |
| |
| from autotest_lib.client.bin import utils |
| |
| USER_TOKEN_NAME = 'User-Specific TPM Token' |
| USER_CHAPS_DIR = '.chaps' |
| TMP_CHAPS_DIR = '/tmp/chaps' |
| CHAPS_DIR_PERM = 0750 |
| CHAPS_SALT_PERM = 0600 |
| |
| |
| def __run_cmd(cmd, ignore_status=False): |
| """Runs a command and returns the output from both stdout and stderr.""" |
| return utils.system_output(cmd + ' 2>&1', retain_output=True, |
| ignore_status=ignore_status).strip() |
| |
| def __get_token_paths(): |
| """Return a dict with a path for each PKCS #11 token currently loaded.""" |
| token_paths = [] |
| for line in __run_cmd('chaps_client --list').split('\n'): |
| match = re.search(r'Slot \d+: (/.*)\s*$', line); |
| if match: |
| token_paths.append(match.group(1)) |
| return token_paths |
| |
| def __get_pkcs11_file_list(token_path): |
| """Return string with PKCS#11 file paths and their associated metadata.""" |
| find_args = '-printf "\'%p\', \'%u:%g\', 0%m\n"' |
| file_list_output = __run_cmd('find %s ' % token_path + find_args) |
| return file_list_output |
| |
| def __verify_tokenname(token_path): |
| """Verify that the TPM token name is correct.""" |
| token_list = __run_cmd('p11_replay --list_tokens') |
| logging.error('token_list: ' + token_list) |
| match = re.search(r'^Slot \d+: (.*)\s*$', token_list, flags=re.MULTILINE) |
| if not match: |
| logging.error('Could not read PKCS#11 token label!') |
| return False |
| token_label = match.group(1) |
| # Accept the legacy token label. |
| if token_label == USER_TOKEN_NAME: |
| return True |
| # The token label should be a canonicalized username which means we should |
| # be able to map it to the token path. This will fail if the UTF-8 username |
| # is more than 32 bytes in length and was truncated to form the PKCS #11 |
| # token label. |
| if len(token_label) == 32: |
| return True |
| obfuscate_cmd = 'cryptohome --action=obfuscate_user --user=%s' % token_label |
| expected_token_path = __run_cmd(obfuscate_cmd) |
| if token_path != expected_token_path: |
| logging.error('Wrong or empty label on the PKCS#11 Token (Got = %s', |
| token_label) |
| return False |
| return True |
| |
| def __verify_permissions(token_path): |
| """Verify that the permissions on the initialized token dir are correct.""" |
| # List of 3-tuples consisting of (path, user:group, octal permissions) |
| # Can be generated (for example), by: |
| # find /home/chronos/user/.chaps -printf "'%p', '%u:%g', 0%m\n" |
| # for i in $paths; do echo \(\'$i\', $(stat --format="'%U:%G', 0%a" $i)\),; |
| # done |
| expected_permissions = [ |
| (token_path, 'chaps:chronos-access', CHAPS_DIR_PERM), |
| ('%s/auth_data_salt' % token_path, 'root:root', CHAPS_SALT_PERM), |
| ('%s/database' % token_path, 'chaps:chronos-access', CHAPS_DIR_PERM)] |
| for item in expected_permissions: |
| path = item[0] |
| (user, group) = item[1].split(':') |
| perms = item[2] |
| stat_buf = os.lstat(path) |
| if not stat_buf: |
| logging.error('Could not stat %s while checking for permissions.', |
| path) |
| return False |
| # Check ownership. |
| path_user = pwd.getpwuid(stat_buf.st_uid).pw_name |
| path_group = grp.getgrgid(stat_buf.st_gid).gr_name |
| if path_user != user or path_group != group: |
| logging.error('Ownership of %s does not match! Got = (%s, %s)' |
| ', Expected = (%s, %s)', path, path_user, path_group, |
| user, group) |
| return False |
| |
| # Check permissions. |
| path_perms = stat.S_IMODE(stat_buf.st_mode) |
| if path_perms != perms: |
| logging.error('Permissions for %s do not match! (Got = %s' |
| ', Expected = %s)', path, oct(path_perms), oct(perms)) |
| return False |
| |
| return True |
| |
| def verify_pkcs11_initialized(): |
| """Checks if the PKCS#11 token is initialized properly.""" |
| token_path_list = __get_token_paths() |
| if len(token_path_list) != 1: |
| logging.error('Expecting a single signed-in user with a token.') |
| return False |
| |
| verify_cmd = ('cryptohome --action=pkcs11_token_status') |
| __run_cmd(verify_cmd) |
| |
| verify_result = True |
| # Do additional sanity tests. |
| if not __verify_tokenname(token_path_list[0]): |
| logging.error('Verification of token name failed!') |
| verify_result = False |
| if not __verify_permissions(token_path_list[0]): |
| logging.error('PKCS#11 file list:\n%s', |
| __get_pkcs11_file_list(token_path_list[0])) |
| logging.error( |
| 'Verification of PKCS#11 subsystem and token permissions failed!') |
| verify_result = False |
| return verify_result |
| |
| def load_p11_test_token(auth_data='1234'): |
| """Loads the test token onto a slot. |
| |
| @param auth_data: The authorization data to use for the token. |
| """ |
| utils.system('sudo chaps_client --load --path=%s --auth="%s"' % |
| (TMP_CHAPS_DIR, auth_data)) |
| |
| def change_p11_test_token_auth_data(auth_data, new_auth_data): |
| """Changes authorization data for the test token. |
| |
| @param auth_data: The current authorization data. |
| @param new_auth_data: The new authorization data. |
| """ |
| utils.system('sudo chaps_client --change_auth --path=%s --auth="%s" ' |
| '--new_auth="%s"' % (TMP_CHAPS_DIR, auth_data, new_auth_data)) |
| |
| def unload_p11_test_token(): |
| """Unloads a loaded test token.""" |
| utils.system('sudo chaps_client --unload --path=%s' % TMP_CHAPS_DIR) |
| |
| def copytree_with_ownership(src, dst): |
| """Like shutil.copytree but also copies owner and group attributes. |
| @param src: Source directory. |
| @param dst: Destination directory. |
| """ |
| utils.system('cp -rp %s %s' % (src, dst)) |
| |
| def setup_p11_test_token(unload_user_tokens, auth_data='1234'): |
| """Configures a PKCS #11 token for testing. |
| |
| Any existing test token will be automatically cleaned up. |
| |
| @param unload_user_tokens: Whether to unload all user tokens. |
| @param auth_data: Initial token authorization data. |
| """ |
| cleanup_p11_test_token() |
| if unload_user_tokens: |
| for path in __get_token_paths(): |
| utils.system('sudo chaps_client --unload --path=%s' % path) |
| os.makedirs(TMP_CHAPS_DIR) |
| uid = pwd.getpwnam('chaps')[2] |
| gid = grp.getgrnam('chronos-access')[2] |
| os.chown(TMP_CHAPS_DIR, uid, gid) |
| os.chmod(TMP_CHAPS_DIR, CHAPS_DIR_PERM) |
| load_p11_test_token(auth_data) |
| unload_p11_test_token() |
| copytree_with_ownership(TMP_CHAPS_DIR, '%s_bak' % TMP_CHAPS_DIR) |
| |
| def restore_p11_test_token(): |
| """Restores a PKCS #11 test token to its initial state.""" |
| shutil.rmtree(TMP_CHAPS_DIR) |
| copytree_with_ownership('%s_bak' % TMP_CHAPS_DIR, TMP_CHAPS_DIR) |
| |
| def get_p11_test_token_db_path(): |
| """Returns the test token database path.""" |
| return '%s/database' % TMP_CHAPS_DIR |
| |
| def verify_p11_test_token(): |
| """Verifies that a test token is working and persistent.""" |
| output = __run_cmd('p11_replay --generate --replay_wifi', |
| ignore_status=True) |
| if not re.search('Sign: CKR_OK', output): |
| print >> sys.stderr, output |
| return False |
| unload_p11_test_token() |
| load_p11_test_token() |
| output = __run_cmd('p11_replay --replay_wifi --cleanup', |
| ignore_status=True) |
| if not re.search('Sign: CKR_OK', output): |
| print >> sys.stderr, output |
| return False |
| return True |
| |
| def cleanup_p11_test_token(): |
| """Deletes the test token.""" |
| unload_p11_test_token() |
| shutil.rmtree(TMP_CHAPS_DIR, ignore_errors=True) |
| shutil.rmtree('%s_bak' % TMP_CHAPS_DIR, ignore_errors=True) |
| |
| def verify_p11_token(): |
| """Verifies that a PKCS #11 token is able to generate key pairs and sign.""" |
| output = __run_cmd('p11_replay --generate --replay_wifi --cleanup', |
| ignore_status=True) |
| return re.search('Sign: CKR_OK', output) |
| |
| def wait_for_pkcs11_token(): |
| """Waits for the PKCS #11 token to be available. |
| |
| This should be called only after a login and is typically called immediately |
| after a login. |
| |
| Returns: |
| True if the token is available. |
| """ |
| try: |
| utils.poll_for_condition( |
| lambda: utils.system('cryptohome --action=pkcs11_token_status', |
| ignore_status=True) == 0, |
| desc='PKCS #11 token.', |
| timeout=300) |
| except utils.TimeoutError: |
| return False |
| return True |