diff options
Diffstat (limited to 'charms/trusty/ceilometer/charmhelpers/contrib/hardening/host/checks')
10 files changed, 823 insertions, 0 deletions
diff --git a/charms/trusty/ceilometer/charmhelpers/contrib/hardening/host/checks/__init__.py b/charms/trusty/ceilometer/charmhelpers/contrib/hardening/host/checks/__init__.py new file mode 100644 index 0000000..c3bd598 --- /dev/null +++ b/charms/trusty/ceilometer/charmhelpers/contrib/hardening/host/checks/__init__.py @@ -0,0 +1,50 @@ +# Copyright 2016 Canonical Limited. +# +# This file is part of charm-helpers. +# +# charm-helpers is free software: you can redistribute it and/or modify +# it under the terms of the GNU Lesser General Public License version 3 as +# published by the Free Software Foundation. +# +# charm-helpers is distributed in the hope that it will be useful, +# but WITHOUT ANY WARRANTY; without even the implied warranty of +# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the +# GNU Lesser General Public License for more details. +# +# You should have received a copy of the GNU Lesser General Public License +# along with charm-helpers. If not, see <http://www.gnu.org/licenses/>. + +from charmhelpers.core.hookenv import ( + log, + DEBUG, +) +from charmhelpers.contrib.hardening.host.checks import ( + apt, + limits, + login, + minimize_access, + pam, + profile, + securetty, + suid_sgid, + sysctl +) + + +def run_os_checks(): + log("Starting OS hardening checks.", level=DEBUG) + checks = apt.get_audits() + checks.extend(limits.get_audits()) + checks.extend(login.get_audits()) + checks.extend(minimize_access.get_audits()) + checks.extend(pam.get_audits()) + checks.extend(profile.get_audits()) + checks.extend(securetty.get_audits()) + checks.extend(suid_sgid.get_audits()) + checks.extend(sysctl.get_audits()) + + for check in checks: + log("Running '%s' check" % (check.__class__.__name__), level=DEBUG) + check.ensure_compliance() + + log("OS hardening checks complete.", level=DEBUG) diff --git a/charms/trusty/ceilometer/charmhelpers/contrib/hardening/host/checks/apt.py b/charms/trusty/ceilometer/charmhelpers/contrib/hardening/host/checks/apt.py new file mode 100644 index 0000000..2c221cd --- /dev/null +++ b/charms/trusty/ceilometer/charmhelpers/contrib/hardening/host/checks/apt.py @@ -0,0 +1,39 @@ +# Copyright 2016 Canonical Limited. +# +# This file is part of charm-helpers. +# +# charm-helpers is free software: you can redistribute it and/or modify +# it under the terms of the GNU Lesser General Public License version 3 as +# published by the Free Software Foundation. +# +# charm-helpers is distributed in the hope that it will be useful, +# but WITHOUT ANY WARRANTY; without even the implied warranty of +# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the +# GNU Lesser General Public License for more details. +# +# You should have received a copy of the GNU Lesser General Public License +# along with charm-helpers. If not, see <http://www.gnu.org/licenses/>. + +from charmhelpers.contrib.hardening.utils import get_settings +from charmhelpers.contrib.hardening.audits.apt import ( + AptConfig, + RestrictedPackages, +) + + +def get_audits(): + """Get OS hardening apt audits. + + :returns: dictionary of audits + """ + audits = [AptConfig([{'key': 'APT::Get::AllowUnauthenticated', + 'expected': 'false'}])] + + settings = get_settings('os') + clean_packages = settings['security']['packages_clean'] + if clean_packages: + security_packages = settings['security']['packages_list'] + if security_packages: + audits.append(RestrictedPackages(security_packages)) + + return audits diff --git a/charms/trusty/ceilometer/charmhelpers/contrib/hardening/host/checks/limits.py b/charms/trusty/ceilometer/charmhelpers/contrib/hardening/host/checks/limits.py new file mode 100644 index 0000000..8ce9dc2 --- /dev/null +++ b/charms/trusty/ceilometer/charmhelpers/contrib/hardening/host/checks/limits.py @@ -0,0 +1,55 @@ +# Copyright 2016 Canonical Limited. +# +# This file is part of charm-helpers. +# +# charm-helpers is free software: you can redistribute it and/or modify +# it under the terms of the GNU Lesser General Public License version 3 as +# published by the Free Software Foundation. +# +# charm-helpers is distributed in the hope that it will be useful, +# but WITHOUT ANY WARRANTY; without even the implied warranty of +# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the +# GNU Lesser General Public License for more details. +# +# You should have received a copy of the GNU Lesser General Public License +# along with charm-helpers. If not, see <http://www.gnu.org/licenses/>. + +from charmhelpers.contrib.hardening.audits.file import ( + DirectoryPermissionAudit, + TemplatedFile, +) +from charmhelpers.contrib.hardening.host import TEMPLATES_DIR +from charmhelpers.contrib.hardening import utils + + +def get_audits(): + """Get OS hardening security limits audits. + + :returns: dictionary of audits + """ + audits = [] + settings = utils.get_settings('os') + + # Ensure that the /etc/security/limits.d directory is only writable + # by the root user, but others can execute and read. + audits.append(DirectoryPermissionAudit('/etc/security/limits.d', + user='root', group='root', + mode=0o755)) + + # If core dumps are not enabled, then don't allow core dumps to be + # created as they may contain sensitive information. + if not settings['security']['kernel_enable_core_dump']: + audits.append(TemplatedFile('/etc/security/limits.d/10.hardcore.conf', + SecurityLimitsContext(), + template_dir=TEMPLATES_DIR, + user='root', group='root', mode=0o0440)) + return audits + + +class SecurityLimitsContext(object): + + def __call__(self): + settings = utils.get_settings('os') + ctxt = {'disable_core_dump': + not settings['security']['kernel_enable_core_dump']} + return ctxt diff --git a/charms/trusty/ceilometer/charmhelpers/contrib/hardening/host/checks/login.py b/charms/trusty/ceilometer/charmhelpers/contrib/hardening/host/checks/login.py new file mode 100644 index 0000000..d32c4f6 --- /dev/null +++ b/charms/trusty/ceilometer/charmhelpers/contrib/hardening/host/checks/login.py @@ -0,0 +1,67 @@ +# Copyright 2016 Canonical Limited. +# +# This file is part of charm-helpers. +# +# charm-helpers is free software: you can redistribute it and/or modify +# it under the terms of the GNU Lesser General Public License version 3 as +# published by the Free Software Foundation. +# +# charm-helpers is distributed in the hope that it will be useful, +# but WITHOUT ANY WARRANTY; without even the implied warranty of +# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the +# GNU Lesser General Public License for more details. +# +# You should have received a copy of the GNU Lesser General Public License +# along with charm-helpers. If not, see <http://www.gnu.org/licenses/>. + +from six import string_types + +from charmhelpers.contrib.hardening.audits.file import TemplatedFile +from charmhelpers.contrib.hardening.host import TEMPLATES_DIR +from charmhelpers.contrib.hardening import utils + + +def get_audits(): + """Get OS hardening login.defs audits. + + :returns: dictionary of audits + """ + audits = [TemplatedFile('/etc/login.defs', LoginContext(), + template_dir=TEMPLATES_DIR, + user='root', group='root', mode=0o0444)] + return audits + + +class LoginContext(object): + + def __call__(self): + settings = utils.get_settings('os') + + # Octal numbers in yaml end up being turned into decimal, + # so check if the umask is entered as a string (e.g. '027') + # or as an octal umask as we know it (e.g. 002). If its not + # a string assume it to be octal and turn it into an octal + # string. + umask = settings['environment']['umask'] + if not isinstance(umask, string_types): + umask = '%s' % oct(umask) + + ctxt = { + 'additional_user_paths': + settings['environment']['extra_user_paths'], + 'umask': umask, + 'pwd_max_age': settings['auth']['pw_max_age'], + 'pwd_min_age': settings['auth']['pw_min_age'], + 'uid_min': settings['auth']['uid_min'], + 'sys_uid_min': settings['auth']['sys_uid_min'], + 'sys_uid_max': settings['auth']['sys_uid_max'], + 'gid_min': settings['auth']['gid_min'], + 'sys_gid_min': settings['auth']['sys_gid_min'], + 'sys_gid_max': settings['auth']['sys_gid_max'], + 'login_retries': settings['auth']['retries'], + 'login_timeout': settings['auth']['timeout'], + 'chfn_restrict': settings['auth']['chfn_restrict'], + 'allow_login_without_home': settings['auth']['allow_homeless'] + } + + return ctxt diff --git a/charms/trusty/ceilometer/charmhelpers/contrib/hardening/host/checks/minimize_access.py b/charms/trusty/ceilometer/charmhelpers/contrib/hardening/host/checks/minimize_access.py new file mode 100644 index 0000000..c471064 --- /dev/null +++ b/charms/trusty/ceilometer/charmhelpers/contrib/hardening/host/checks/minimize_access.py @@ -0,0 +1,52 @@ +# Copyright 2016 Canonical Limited. +# +# This file is part of charm-helpers. +# +# charm-helpers is free software: you can redistribute it and/or modify +# it under the terms of the GNU Lesser General Public License version 3 as +# published by the Free Software Foundation. +# +# charm-helpers is distributed in the hope that it will be useful, +# but WITHOUT ANY WARRANTY; without even the implied warranty of +# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the +# GNU Lesser General Public License for more details. +# +# You should have received a copy of the GNU Lesser General Public License +# along with charm-helpers. If not, see <http://www.gnu.org/licenses/>. + +from charmhelpers.contrib.hardening.audits.file import ( + FilePermissionAudit, + ReadOnly, +) +from charmhelpers.contrib.hardening import utils + + +def get_audits(): + """Get OS hardening access audits. + + :returns: dictionary of audits + """ + audits = [] + settings = utils.get_settings('os') + + # Remove write permissions from $PATH folders for all regular users. + # This prevents changing system-wide commands from normal users. + path_folders = {'/usr/local/sbin', + '/usr/local/bin', + '/usr/sbin', + '/usr/bin', + '/bin'} + extra_user_paths = settings['environment']['extra_user_paths'] + path_folders.update(extra_user_paths) + audits.append(ReadOnly(path_folders)) + + # Only allow the root user to have access to the shadow file. + audits.append(FilePermissionAudit('/etc/shadow', 'root', 'root', 0o0600)) + + if 'change_user' not in settings['security']['users_allow']: + # su should only be accessible to user and group root, unless it is + # expressly defined to allow users to change to root via the + # security_users_allow config option. + audits.append(FilePermissionAudit('/bin/su', 'root', 'root', 0o750)) + + return audits diff --git a/charms/trusty/ceilometer/charmhelpers/contrib/hardening/host/checks/pam.py b/charms/trusty/ceilometer/charmhelpers/contrib/hardening/host/checks/pam.py new file mode 100644 index 0000000..383fe28 --- /dev/null +++ b/charms/trusty/ceilometer/charmhelpers/contrib/hardening/host/checks/pam.py @@ -0,0 +1,134 @@ +# Copyright 2016 Canonical Limited. +# +# This file is part of charm-helpers. +# +# charm-helpers is free software: you can redistribute it and/or modify +# it under the terms of the GNU Lesser General Public License version 3 as +# published by the Free Software Foundation. +# +# charm-helpers is distributed in the hope that it will be useful, +# but WITHOUT ANY WARRANTY; without even the implied warranty of +# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the +# GNU Lesser General Public License for more details. +# +# You should have received a copy of the GNU Lesser General Public License +# along with charm-helpers. If not, see <http://www.gnu.org/licenses/>. + +from subprocess import ( + check_output, + CalledProcessError, +) + +from charmhelpers.core.hookenv import ( + log, + DEBUG, + ERROR, +) +from charmhelpers.fetch import ( + apt_install, + apt_purge, + apt_update, +) +from charmhelpers.contrib.hardening.audits.file import ( + TemplatedFile, + DeletedFile, +) +from charmhelpers.contrib.hardening import utils +from charmhelpers.contrib.hardening.host import TEMPLATES_DIR + + +def get_audits(): + """Get OS hardening PAM authentication audits. + + :returns: dictionary of audits + """ + audits = [] + + settings = utils.get_settings('os') + + if settings['auth']['pam_passwdqc_enable']: + audits.append(PasswdqcPAM('/etc/passwdqc.conf')) + + if settings['auth']['retries']: + audits.append(Tally2PAM('/usr/share/pam-configs/tally2')) + else: + audits.append(DeletedFile('/usr/share/pam-configs/tally2')) + + return audits + + +class PasswdqcPAMContext(object): + + def __call__(self): + ctxt = {} + settings = utils.get_settings('os') + + ctxt['auth_pam_passwdqc_options'] = \ + settings['auth']['pam_passwdqc_options'] + + return ctxt + + +class PasswdqcPAM(TemplatedFile): + """The PAM Audit verifies the linux PAM settings.""" + def __init__(self, path): + super(PasswdqcPAM, self).__init__(path=path, + template_dir=TEMPLATES_DIR, + context=PasswdqcPAMContext(), + user='root', + group='root', + mode=0o0640) + + def pre_write(self): + # Always remove? + for pkg in ['libpam-ccreds', 'libpam-cracklib']: + log("Purging package '%s'" % pkg, level=DEBUG), + apt_purge(pkg) + + apt_update(fatal=True) + for pkg in ['libpam-passwdqc']: + log("Installing package '%s'" % pkg, level=DEBUG), + apt_install(pkg) + + def post_write(self): + """Updates the PAM configuration after the file has been written""" + try: + check_output(['pam-auth-update', '--package']) + except CalledProcessError as e: + log('Error calling pam-auth-update: %s' % e, level=ERROR) + + +class Tally2PAMContext(object): + + def __call__(self): + ctxt = {} + settings = utils.get_settings('os') + + ctxt['auth_lockout_time'] = settings['auth']['lockout_time'] + ctxt['auth_retries'] = settings['auth']['retries'] + + return ctxt + + +class Tally2PAM(TemplatedFile): + """The PAM Audit verifies the linux PAM settings.""" + def __init__(self, path): + super(Tally2PAM, self).__init__(path=path, + template_dir=TEMPLATES_DIR, + context=Tally2PAMContext(), + user='root', + group='root', + mode=0o0640) + + def pre_write(self): + # Always remove? + apt_purge('libpam-ccreds') + apt_update(fatal=True) + apt_install('libpam-modules') + + def post_write(self): + """Updates the PAM configuration after the file has been written""" + try: + check_output(['pam-auth-update', '--package']) + except CalledProcessError as e: + log('Error calling pam-auth-update: %s' % e, level=ERROR) diff --git a/charms/trusty/ceilometer/charmhelpers/contrib/hardening/host/checks/profile.py b/charms/trusty/ceilometer/charmhelpers/contrib/hardening/host/checks/profile.py new file mode 100644 index 0000000..f744335 --- /dev/null +++ b/charms/trusty/ceilometer/charmhelpers/contrib/hardening/host/checks/profile.py @@ -0,0 +1,45 @@ +# Copyright 2016 Canonical Limited. +# +# This file is part of charm-helpers. +# +# charm-helpers is free software: you can redistribute it and/or modify +# it under the terms of the GNU Lesser General Public License version 3 as +# published by the Free Software Foundation. +# +# charm-helpers is distributed in the hope that it will be useful, +# but WITHOUT ANY WARRANTY; without even the implied warranty of +# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the +# GNU Lesser General Public License for more details. +# +# You should have received a copy of the GNU Lesser General Public License +# along with charm-helpers. If not, see <http://www.gnu.org/licenses/>. + +from charmhelpers.contrib.hardening.audits.file import TemplatedFile +from charmhelpers.contrib.hardening.host import TEMPLATES_DIR +from charmhelpers.contrib.hardening import utils + + +def get_audits(): + """Get OS hardening profile audits. + + :returns: dictionary of audits + """ + audits = [] + + settings = utils.get_settings('os') + + # If core dumps are not enabled, then don't allow core dumps to be + # created as they may contain sensitive information. + if not settings['security']['kernel_enable_core_dump']: + audits.append(TemplatedFile('/etc/profile.d/pinerolo_profile.sh', + ProfileContext(), + template_dir=TEMPLATES_DIR, + mode=0o0755, user='root', group='root')) + return audits + + +class ProfileContext(object): + + def __call__(self): + ctxt = {} + return ctxt diff --git a/charms/trusty/ceilometer/charmhelpers/contrib/hardening/host/checks/securetty.py b/charms/trusty/ceilometer/charmhelpers/contrib/hardening/host/checks/securetty.py new file mode 100644 index 0000000..e33c73c --- /dev/null +++ b/charms/trusty/ceilometer/charmhelpers/contrib/hardening/host/checks/securetty.py @@ -0,0 +1,39 @@ +# Copyright 2016 Canonical Limited. +# +# This file is part of charm-helpers. +# +# charm-helpers is free software: you can redistribute it and/or modify +# it under the terms of the GNU Lesser General Public License version 3 as +# published by the Free Software Foundation. +# +# charm-helpers is distributed in the hope that it will be useful, +# but WITHOUT ANY WARRANTY; without even the implied warranty of +# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the +# GNU Lesser General Public License for more details. +# +# You should have received a copy of the GNU Lesser General Public License +# along with charm-helpers. If not, see <http://www.gnu.org/licenses/>. + +from charmhelpers.contrib.hardening.audits.file import TemplatedFile +from charmhelpers.contrib.hardening.host import TEMPLATES_DIR +from charmhelpers.contrib.hardening import utils + + +def get_audits(): + """Get OS hardening Secure TTY audits. + + :returns: dictionary of audits + """ + audits = [] + audits.append(TemplatedFile('/etc/securetty', SecureTTYContext(), + template_dir=TEMPLATES_DIR, + mode=0o0400, user='root', group='root')) + return audits + + +class SecureTTYContext(object): + + def __call__(self): + settings = utils.get_settings('os') + ctxt = {'ttys': settings['auth']['root_ttys']} + return ctxt diff --git a/charms/trusty/ceilometer/charmhelpers/contrib/hardening/host/checks/suid_sgid.py b/charms/trusty/ceilometer/charmhelpers/contrib/hardening/host/checks/suid_sgid.py new file mode 100644 index 0000000..0534689 --- /dev/null +++ b/charms/trusty/ceilometer/charmhelpers/contrib/hardening/host/checks/suid_sgid.py @@ -0,0 +1,131 @@ +# Copyright 2016 Canonical Limited. +# +# This file is part of charm-helpers. +# +# charm-helpers is free software: you can redistribute it and/or modify +# it under the terms of the GNU Lesser General Public License version 3 as +# published by the Free Software Foundation. +# +# charm-helpers is distributed in the hope that it will be useful, +# but WITHOUT ANY WARRANTY; without even the implied warranty of +# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the +# GNU Lesser General Public License for more details. +# +# You should have received a copy of the GNU Lesser General Public License +# along with charm-helpers. If not, see <http://www.gnu.org/licenses/>. + +import subprocess + +from charmhelpers.core.hookenv import ( + log, + INFO, +) +from charmhelpers.contrib.hardening.audits.file import NoSUIDSGIDAudit +from charmhelpers.contrib.hardening import utils + + +BLACKLIST = ['/usr/bin/rcp', '/usr/bin/rlogin', '/usr/bin/rsh', + '/usr/libexec/openssh/ssh-keysign', + '/usr/lib/openssh/ssh-keysign', + '/sbin/netreport', + '/usr/sbin/usernetctl', + '/usr/sbin/userisdnctl', + '/usr/sbin/pppd', + '/usr/bin/lockfile', + '/usr/bin/mail-lock', + '/usr/bin/mail-unlock', + '/usr/bin/mail-touchlock', + '/usr/bin/dotlockfile', + '/usr/bin/arping', + '/usr/sbin/uuidd', + '/usr/bin/mtr', + '/usr/lib/evolution/camel-lock-helper-1.2', + '/usr/lib/pt_chown', + '/usr/lib/eject/dmcrypt-get-device', + '/usr/lib/mc/cons.saver'] + +WHITELIST = ['/bin/mount', '/bin/ping', '/bin/su', '/bin/umount', + '/sbin/pam_timestamp_check', '/sbin/unix_chkpwd', '/usr/bin/at', + '/usr/bin/gpasswd', '/usr/bin/locate', '/usr/bin/newgrp', + '/usr/bin/passwd', '/usr/bin/ssh-agent', + '/usr/libexec/utempter/utempter', '/usr/sbin/lockdev', + '/usr/sbin/sendmail.sendmail', '/usr/bin/expiry', + '/bin/ping6', '/usr/bin/traceroute6.iputils', + '/sbin/mount.nfs', '/sbin/umount.nfs', + '/sbin/mount.nfs4', '/sbin/umount.nfs4', + '/usr/bin/crontab', + '/usr/bin/wall', '/usr/bin/write', + '/usr/bin/screen', + '/usr/bin/mlocate', + '/usr/bin/chage', '/usr/bin/chfn', '/usr/bin/chsh', + '/bin/fusermount', + '/usr/bin/pkexec', + '/usr/bin/sudo', '/usr/bin/sudoedit', + '/usr/sbin/postdrop', '/usr/sbin/postqueue', + '/usr/sbin/suexec', + '/usr/lib/squid/ncsa_auth', '/usr/lib/squid/pam_auth', + '/usr/kerberos/bin/ksu', + '/usr/sbin/ccreds_validate', + '/usr/bin/Xorg', + '/usr/bin/X', + '/usr/lib/dbus-1.0/dbus-daemon-launch-helper', + '/usr/lib/vte/gnome-pty-helper', + '/usr/lib/libvte9/gnome-pty-helper', + '/usr/lib/libvte-2.90-9/gnome-pty-helper'] + + +def get_audits(): + """Get OS hardening suid/sgid audits. + + :returns: dictionary of audits + """ + checks = [] + settings = utils.get_settings('os') + if not settings['security']['suid_sgid_enforce']: + log("Skipping suid/sgid hardening", level=INFO) + return checks + + # Build the blacklist and whitelist of files for suid/sgid checks. + # There are a total of 4 lists: + # 1. the system blacklist + # 2. the system whitelist + # 3. the user blacklist + # 4. the user whitelist + # + # The blacklist is the set of paths which should NOT have the suid/sgid bit + # set and the whitelist is the set of paths which MAY have the suid/sgid + # bit setl. The user whitelist/blacklist effectively override the system + # whitelist/blacklist. + u_b = settings['security']['suid_sgid_blacklist'] + u_w = settings['security']['suid_sgid_whitelist'] + + blacklist = set(BLACKLIST) - set(u_w + u_b) + whitelist = set(WHITELIST) - set(u_b + u_w) + + checks.append(NoSUIDSGIDAudit(blacklist)) + + dry_run = settings['security']['suid_sgid_dry_run_on_unknown'] + + if settings['security']['suid_sgid_remove_from_unknown'] or dry_run: + # If the policy is a dry_run (e.g. complain only) or remove unknown + # suid/sgid bits then find all of the paths which have the suid/sgid + # bit set and then remove the whitelisted paths. + root_path = settings['environment']['root_path'] + unknown_paths = find_paths_with_suid_sgid(root_path) - set(whitelist) + checks.append(NoSUIDSGIDAudit(unknown_paths, unless=dry_run)) + + return checks + + +def find_paths_with_suid_sgid(root_path): + """Finds all paths/files which have an suid/sgid bit enabled. + + Starting with the root_path, this will recursively find all paths which + have an suid or sgid bit set. + """ + cmd = ['find', root_path, '-perm', '-4000', '-o', '-perm', '-2000', + '-type', 'f', '!', '-path', '/proc/*', '-print'] + + p = subprocess.Popen(cmd, stdout=subprocess.PIPE, stderr=subprocess.PIPE) + out, _ = p.communicate() + return set(out.split('\n')) diff --git a/charms/trusty/ceilometer/charmhelpers/contrib/hardening/host/checks/sysctl.py b/charms/trusty/ceilometer/charmhelpers/contrib/hardening/host/checks/sysctl.py new file mode 100644 index 0000000..4a76d74 --- /dev/null +++ b/charms/trusty/ceilometer/charmhelpers/contrib/hardening/host/checks/sysctl.py @@ -0,0 +1,211 @@ +# Copyright 2016 Canonical Limited. +# +# This file is part of charm-helpers. +# +# charm-helpers is free software: you can redistribute it and/or modify +# it under the terms of the GNU Lesser General Public License version 3 as +# published by the Free Software Foundation. +# +# charm-helpers is distributed in the hope that it will be useful, +# but WITHOUT ANY WARRANTY; without even the implied warranty of +# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the +# GNU Lesser General Public License for more details. +# +# You should have received a copy of the GNU Lesser General Public License +# along with charm-helpers. If not, see <http://www.gnu.org/licenses/>. + +import os +import platform +import re +import six +import subprocess + +from charmhelpers.core.hookenv import ( + log, + INFO, + WARNING, +) +from charmhelpers.contrib.hardening import utils +from charmhelpers.contrib.hardening.audits.file import ( + FilePermissionAudit, + TemplatedFile, +) +from charmhelpers.contrib.hardening.host import TEMPLATES_DIR + + +SYSCTL_DEFAULTS = """net.ipv4.ip_forward=%(net_ipv4_ip_forward)s +net.ipv6.conf.all.forwarding=%(net_ipv6_conf_all_forwarding)s +net.ipv4.conf.all.rp_filter=1 +net.ipv4.conf.default.rp_filter=1 +net.ipv4.icmp_echo_ignore_broadcasts=1 +net.ipv4.icmp_ignore_bogus_error_responses=1 +net.ipv4.icmp_ratelimit=100 +net.ipv4.icmp_ratemask=88089 +net.ipv6.conf.all.disable_ipv6=%(net_ipv6_conf_all_disable_ipv6)s +net.ipv4.tcp_timestamps=%(net_ipv4_tcp_timestamps)s +net.ipv4.conf.all.arp_ignore=%(net_ipv4_conf_all_arp_ignore)s +net.ipv4.conf.all.arp_announce=%(net_ipv4_conf_all_arp_announce)s +net.ipv4.tcp_rfc1337=1 +net.ipv4.tcp_syncookies=1 +net.ipv4.conf.all.shared_media=1 +net.ipv4.conf.default.shared_media=1 +net.ipv4.conf.all.accept_source_route=0 +net.ipv4.conf.default.accept_source_route=0 +net.ipv4.conf.all.accept_redirects=0 +net.ipv4.conf.default.accept_redirects=0 +net.ipv6.conf.all.accept_redirects=0 +net.ipv6.conf.default.accept_redirects=0 +net.ipv4.conf.all.secure_redirects=0 +net.ipv4.conf.default.secure_redirects=0 +net.ipv4.conf.all.send_redirects=0 +net.ipv4.conf.default.send_redirects=0 +net.ipv4.conf.all.log_martians=0 +net.ipv6.conf.default.router_solicitations=0 +net.ipv6.conf.default.accept_ra_rtr_pref=0 +net.ipv6.conf.default.accept_ra_pinfo=0 +net.ipv6.conf.default.accept_ra_defrtr=0 +net.ipv6.conf.default.autoconf=0 +net.ipv6.conf.default.dad_transmits=0 +net.ipv6.conf.default.max_addresses=1 +net.ipv6.conf.all.accept_ra=0 +net.ipv6.conf.default.accept_ra=0 +kernel.modules_disabled=%(kernel_modules_disabled)s +kernel.sysrq=%(kernel_sysrq)s +fs.suid_dumpable=%(fs_suid_dumpable)s +kernel.randomize_va_space=2 +""" + + +def get_audits(): + """Get OS hardening sysctl audits. + + :returns: dictionary of audits + """ + audits = [] + settings = utils.get_settings('os') + + # Apply the sysctl settings which are configured to be applied. + audits.append(SysctlConf()) + # Make sure that only root has access to the sysctl.conf file, and + # that it is read-only. + audits.append(FilePermissionAudit('/etc/sysctl.conf', + user='root', + group='root', mode=0o0440)) + # If module loading is not enabled, then ensure that the modules + # file has the appropriate permissions and rebuild the initramfs + if not settings['security']['kernel_enable_module_loading']: + audits.append(ModulesTemplate()) + + return audits + + +class ModulesContext(object): + + def __call__(self): + settings = utils.get_settings('os') + with open('/proc/cpuinfo', 'r') as fd: + cpuinfo = fd.readlines() + + for line in cpuinfo: + match = re.search(r"^vendor_id\s+:\s+(.+)", line) + if match: + vendor = match.group(1) + + if vendor == "GenuineIntel": + vendor = "intel" + elif vendor == "AuthenticAMD": + vendor = "amd" + + ctxt = {'arch': platform.processor(), + 'cpuVendor': vendor, + 'desktop_enable': settings['general']['desktop_enable']} + + return ctxt + + +class ModulesTemplate(object): + + def __init__(self): + super(ModulesTemplate, self).__init__('/etc/initramfs-tools/modules', + ModulesContext(), + templates_dir=TEMPLATES_DIR, + user='root', group='root', + mode=0o0440) + + def post_write(self): + subprocess.check_call(['update-initramfs', '-u']) + + +class SysCtlHardeningContext(object): + def __call__(self): + settings = utils.get_settings('os') + ctxt = {'sysctl': {}} + + log("Applying sysctl settings", level=INFO) + extras = {'net_ipv4_ip_forward': 0, + 'net_ipv6_conf_all_forwarding': 0, + 'net_ipv6_conf_all_disable_ipv6': 1, + 'net_ipv4_tcp_timestamps': 0, + 'net_ipv4_conf_all_arp_ignore': 0, + 'net_ipv4_conf_all_arp_announce': 0, + 'kernel_sysrq': 0, + 'fs_suid_dumpable': 0, + 'kernel_modules_disabled': 1} + + if settings['sysctl']['ipv6_enable']: + extras['net_ipv6_conf_all_disable_ipv6'] = 0 + + if settings['sysctl']['forwarding']: + extras['net_ipv4_ip_forward'] = 1 + extras['net_ipv6_conf_all_forwarding'] = 1 + + if settings['sysctl']['arp_restricted']: + extras['net_ipv4_conf_all_arp_ignore'] = 1 + extras['net_ipv4_conf_all_arp_announce'] = 2 + + if settings['security']['kernel_enable_module_loading']: + extras['kernel_modules_disabled'] = 0 + + if settings['sysctl']['kernel_enable_sysrq']: + sysrq_val = settings['sysctl']['kernel_secure_sysrq'] + extras['kernel_sysrq'] = sysrq_val + + if settings['security']['kernel_enable_core_dump']: + extras['fs_suid_dumpable'] = 1 + + settings.update(extras) + for d in (SYSCTL_DEFAULTS % settings).split(): + d = d.strip().partition('=') + key = d[0].strip() + path = os.path.join('/proc/sys', key.replace('.', '/')) + if not os.path.exists(path): + log("Skipping '%s' since '%s' does not exist" % (key, path), + level=WARNING) + continue + + ctxt['sysctl'][key] = d[2] or None + + # Translate for python3 + return {'sysctl_settings': + [(k, v) for k, v in six.iteritems(ctxt['sysctl'])]} + + +class SysctlConf(TemplatedFile): + """An audit check for sysctl settings.""" + def __init__(self): + self.conffile = '/etc/sysctl.d/99-juju-hardening.conf' + super(SysctlConf, self).__init__(self.conffile, + SysCtlHardeningContext(), + template_dir=TEMPLATES_DIR, + user='root', group='root', + mode=0o0440) + + def post_write(self): + try: + subprocess.check_call(['sysctl', '-p', self.conffile]) + except subprocess.CalledProcessError as e: + # NOTE: on some systems if sysctl cannot apply all settings it + # will return non-zero as well. + log("sysctl command returned an error (maybe some " + "keys could not be set) - %s" % (e), + level=WARNING) |