freeipa/ipaserver/plugins/caacl.py

#
# Copyright (C) 2015  FreeIPA Contributors see COPYING for license
#

import pyhbac
import six

from ipalib import api, errors, output
from ipalib import Bool, Str, StrEnum
from ipalib.constants import IPA_CA_CN
from ipalib.plugable import Registry
from .baseldap import (
    LDAPObject, LDAPSearch, LDAPCreate, LDAPDelete, LDAPQuery,
    LDAPUpdate, LDAPRetrieve, LDAPAddMember, LDAPRemoveMember,
    global_output_params, pkey_to_value)
from .hbacrule import is_all
from ipalib import _, ngettext
from ipapython.dn import DN

if six.PY3:
    unicode = str

__doc__ = _("""
Manage CA ACL rules.

This plugin is used to define rules governing which CAs and profiles
may be used to issue certificates to particular principals or groups
of principals.

SUBJECT PRINCIPAL SCOPE:

For a certificate request to be allowed, the principal(s) that are
the subject of a certificate request (not necessarily the principal
actually requesting the certificate) must be included in the scope
of a CA ACL that also includes the target CA and profile.

Users can be included by name, group or the "all users" category.
Hosts can be included by name, hostgroup or the "all hosts"
category.  Services can be included by service name or the "all
services" category.  CA ACLs may be associated with a single type of
principal, or multiple types.

CERTIFICATE AUTHORITY SCOPE:

A CA ACL can be associated with one or more CAs by name, or by the
"all CAs" category.  For compatibility reasons, a CA ACL with no CA
association implies an association with the 'ipa' CA (and only this
CA).

PROFILE SCOPE:

A CA ACL can be associated with one or more profiles by Profile ID.
The Profile ID is a string without spaces or punctuation starting
with a letter and followed by a sequence of letters, digits or
underscore ("_").

EXAMPLES:

  Create a CA ACL "test" that grants all users access to the
  "UserCert" profile on all CAs:
    ipa caacl-add test --usercat=all --cacat=all
    ipa caacl-add-profile test --certprofiles UserCert

  Display the properties of a named CA ACL:
    ipa caacl-show test

  Create a CA ACL to let user "alice" use the "DNP3" profile on "DNP3-CA":
    ipa caacl-add alice_dnp3
    ipa caacl-add-ca alice_dnp3 --cas DNP3-CA
    ipa caacl-add-profile alice_dnp3 --certprofiles DNP3
    ipa caacl-add-user alice_dnp3 --user=alice

  Disable a CA ACL:
    ipa caacl-disable test

  Remove a CA ACL:
    ipa caacl-del test
""")

register = Registry()


def _acl_make_request(principal_type, principal, ca_id, profile_id):
    """Construct HBAC request for the given principal, CA and profile"""

    req = pyhbac.HbacRequest()
    req.targethost.name = ca_id
    req.service.name = profile_id
    if principal_type == 'user':
        req.user.name = principal.username
    elif principal_type == 'host':
        req.user.name = principal.hostname
    elif principal_type == 'service':
        req.user.name = unicode(principal)
    groups = []
    if principal_type == 'user':
        user_obj = api.Command.user_show(principal.username)['result']
        groups = user_obj.get('memberof_group', [])
        groups += user_obj.get('memberofindirect_group', [])
    elif principal_type == 'host':
        host_obj = api.Command.host_show(principal.hostname)['result']
        groups = host_obj.get('memberof_hostgroup', [])
        groups += host_obj.get('memberofindirect_hostgroup', [])
    req.user.groups = sorted(set(groups))
    return req


def _acl_make_rule(principal_type, obj):
    """Turn CA ACL object into HBAC rule.

    ``principal_type``
        String in {'user', 'host', 'service'}
    """
    rule = pyhbac.HbacRule(obj['cn'][0])
    rule.enabled = obj['ipaenabledflag'][0]
    rule.srchosts.category = {pyhbac.HBAC_CATEGORY_ALL}

    # add CA(s)
    if 'ipacacategory' in obj and obj['ipacacategory'][0].lower() == 'all':
        rule.targethosts.category = {pyhbac.HBAC_CATEGORY_ALL}
    else:
        # For compatibility with pre-lightweight-CAs CA ACLs,
        # no CA members implies the host authority (only)
        rule.targethosts.names = obj.get('ipamemberca_ca', [IPA_CA_CN])

    # add profiles
    if ('ipacertprofilecategory' in obj
            and obj['ipacertprofilecategory'][0].lower() == 'all'):
        rule.services.category = {pyhbac.HBAC_CATEGORY_ALL}
    else:
        attr = 'ipamembercertprofile_certprofile'
        rule.services.names = obj.get(attr, [])

    # add principals and principal's groups
    category_attr = '{}category'.format(principal_type)
    if category_attr in obj and obj[category_attr][0].lower() == 'all':
        rule.users.category = {pyhbac.HBAC_CATEGORY_ALL}
    else:
        if principal_type == 'user':
            rule.users.names = obj.get('memberuser_user', [])
            rule.users.groups = obj.get('memberuser_group', [])
        elif principal_type == 'host':
            rule.users.names = obj.get('memberhost_host', [])
            rule.users.groups = obj.get('memberhost_hostgroup', [])
        elif principal_type == 'service':
            rule.users.names = [
                unicode(principal)
                for principal in obj.get('memberservice_service', [])
            ]

    return rule


def acl_evaluate(principal, ca_id, profile_id):
    if principal.is_user:
        principal_type = 'user'
    elif principal.is_host:
        principal_type = 'host'
    else:
        principal_type = 'service'
    req = _acl_make_request(principal_type, principal, ca_id, profile_id)
    acls = api.Command.caacl_find(no_members=False)['result']
    rules = [_acl_make_rule(principal_type, obj) for obj in acls]
    return req.evaluate(rules) == pyhbac.HBAC_EVAL_ALLOW


@register()
class caacl(LDAPObject):
    """
    CA ACL object.
    """
    container_dn = api.env.container_caacl
    object_name = _('CA ACL')
    object_name_plural = _('CA ACLs')
    object_class = ['ipaassociation', 'ipacaacl']
    permission_filter_objectclasses = ['ipacaacl']
    default_attributes = [
        'cn', 'description', 'ipaenabledflag',
        'ipacacategory', 'ipamemberca',
        'ipacertprofilecategory', 'ipamembercertprofile',
        'usercategory', 'memberuser',
        'hostcategory', 'memberhost',
        'servicecategory', 'memberservice',
    ]
    uuid_attribute = 'ipauniqueid'
    rdn_attribute = 'ipauniqueid'
    attribute_members = {
        'memberuser': ['user', 'group'],
        'memberhost': ['host', 'hostgroup'],
        'memberservice': ['service'],
        'ipamemberca': ['ca'],
        'ipamembercertprofile': ['certprofile'],
    }
    managed_permissions = {
        'System: Read CA ACLs': {
            'replaces_global_anonymous_aci': True,
            'ipapermbindruletype': 'all',
            'ipapermright': {'read', 'search', 'compare'},
            'ipapermdefaultattr': {
                'cn', 'description', 'ipaenabledflag',
                'ipacacategory', 'ipamemberca',
                'ipacertprofilecategory', 'ipamembercertprofile',
                'usercategory', 'memberuser',
                'hostcategory', 'memberhost',
                'servicecategory', 'memberservice',
                'ipauniqueid',
                'objectclass', 'member',
            },
        },
        'System: Add CA ACL': {
            'ipapermright': {'add'},
            'replaces': [
                '(target = "ldap:///ipauniqueid=*,cn=caacls,cn=ca,$SUFFIX")(version 3.0;acl "permission:Add CA ACL";allow (add) groupdn = "ldap:///cn=Add CA ACL,cn=permissions,cn=pbac,$SUFFIX";)',
            ],
            'default_privileges': {'CA Administrator'},
        },
        'System: Delete CA ACL': {
            'ipapermright': {'delete'},
            'replaces': [
                '(target = "ldap:///ipauniqueid=*,cn=caacls,cn=ca,$SUFFIX")(version 3.0;acl "permission:Delete CA ACL";allow (delete) groupdn = "ldap:///cn=Delete CA ACL,cn=permissions,cn=pbac,$SUFFIX";)',
            ],
            'default_privileges': {'CA Administrator'},
        },
        'System: Manage CA ACL Membership': {
            'ipapermright': {'write'},
            'ipapermdefaultattr': {
                'ipacacategory', 'ipamemberca',
                'ipacertprofilecategory', 'ipamembercertprofile',
                'usercategory', 'memberuser',
                'hostcategory', 'memberhost',
                'servicecategory', 'memberservice'
            },
            'replaces': [
                '(targetattr = "ipamemberca || ipamembercertprofile || memberuser || memberservice || memberhost || ipacacategory || ipacertprofilecategory || usercategory || hostcategory || servicecategory")(target = "ldap:///ipauniqueid=*,cn=caacls,cn=ca,$SUFFIX")(version 3.0;acl "permission:Manage CA ACL membership";allow (write) groupdn = "ldap:///cn=Manage CA ACL membership,cn=permissions,cn=pbac,$SUFFIX";)',
            ],
            'default_privileges': {'CA Administrator'},
        },
        'System: Modify CA ACL': {
            'ipapermright': {'write'},
            'ipapermdefaultattr': {
                'cn', 'description', 'ipaenabledflag',
            },
            'replaces': [
                '(targetattr = "cn || description || ipaenabledflag")(target = "ldap:///ipauniqueid=*,cn=caacls,cn=ca,$SUFFIX")(version 3.0;acl "permission:Modify CA ACL";allow (write) groupdn = "ldap:///cn=Modify CA ACL,cn=permissions,cn=pbac,$SUFFIX";)',
            ],
            'default_privileges': {'CA Administrator'},
        },
    }

    label = _('CA ACLs')
    label_singular = _('CA ACL')

    takes_params = (
        Str('cn',
            cli_name='name',
            label=_('ACL name'),
            primary_key=True,
        ),
        Str('description?',
            cli_name='desc',
            label=_('Description'),
        ),
        Bool('ipaenabledflag?',
             label=_('Enabled'),
             flags=['no_option'],
        ),
        StrEnum('ipacacategory?',
            cli_name='cacat',
            label=_('CA category'),
            doc=_('CA category the ACL applies to'),
            values=(u'all', ),
        ),
        StrEnum('ipacertprofilecategory?',
            cli_name='profilecat',
            label=_('Profile category'),
            doc=_('Profile category the ACL applies to'),
            values=(u'all', ),
        ),
        StrEnum('usercategory?',
            cli_name='usercat',
            label=_('User category'),
            doc=_('User category the ACL applies to'),
            values=(u'all', ),
        ),
        StrEnum('hostcategory?',
            cli_name='hostcat',
            label=_('Host category'),
            doc=_('Host category the ACL applies to'),
            values=(u'all', ),
        ),
        StrEnum('servicecategory?',
            cli_name='servicecat',
            label=_('Service category'),
            doc=_('Service category the ACL applies to'),
            values=(u'all', ),
        ),
        Str('ipamemberca_ca?',
            label=_('CAs'),
            flags=['no_create', 'no_update', 'no_search'],
        ),
        Str('ipamembercertprofile_certprofile?',
            label=_('Profiles'),
            flags=['no_create', 'no_update', 'no_search'],
        ),
        Str('memberuser_user?',
            label=_('Users'),
            flags=['no_create', 'no_update', 'no_search'],
        ),
        Str('memberuser_group?',
            label=_('User Groups'),
            flags=['no_create', 'no_update', 'no_search'],
        ),
        Str('memberhost_host?',
            label=_('Hosts'),
            flags=['no_create', 'no_update', 'no_search'],
        ),
        Str('memberhost_hostgroup?',
            label=_('Host Groups'),
            flags=['no_create', 'no_update', 'no_search'],
        ),
        Str('memberservice_service?',
            label=_('Services'),
            flags=['no_create', 'no_update', 'no_search'],
        ),
    )


@register()
class caacl_add(LDAPCreate):
    __doc__ = _('Create a new CA ACL.')

    msg_summary = _('Added CA ACL "%(value)s"')

    def pre_callback(self, ldap, dn, entry_attrs, attrs_list, *keys, **options):
        # CA ACLs are enabled by default
        entry_attrs['ipaenabledflag'] = ['TRUE']
        return dn


@register()
class caacl_del(LDAPDelete):
    __doc__ = _('Delete a CA ACL.')

    msg_summary = _('Deleted CA ACL "%(value)s"')

    def pre_callback(self, ldap, dn, *keys, **options):
        if keys[0] == 'hosts_services_caIPAserviceCert':
            raise errors.ProtectedEntryError(
                label=_("CA ACL"),
                key=keys[0],
                reason=_("default CA ACL can be only disabled"))
        return dn


@register()
class caacl_mod(LDAPUpdate):
    __doc__ = _('Modify a CA ACL.')

    msg_summary = _('Modified CA ACL "%(value)s"')

    def pre_callback(self, ldap, dn, entry_attrs, attrs_list, *keys, **options):
        assert isinstance(dn, DN)
        try:
            entry_attrs = ldap.get_entry(dn, attrs_list)
            dn = entry_attrs.dn
        except errors.NotFound:
            self.obj.handle_not_found(*keys)

        if is_all(options, 'ipacacategory') and 'ipamemberca' in entry_attrs:
            raise errors.MutuallyExclusiveError(reason=_(
                "CA category cannot be set to 'all' "
                "while there are allowed CAs"))
        if (is_all(options, 'ipacertprofilecategory')
                and 'ipamembercertprofile' in entry_attrs):
            raise errors.MutuallyExclusiveError(reason=_(
                "profile category cannot be set to 'all' "
                "while there are allowed profiles"))
        if is_all(options, 'usercategory') and 'memberuser' in entry_attrs:
            raise errors.MutuallyExclusiveError(reason=_(
                "user category cannot be set to 'all' "
                "while there are allowed users"))
        if is_all(options, 'hostcategory') and 'memberhost' in entry_attrs:
            raise errors.MutuallyExclusiveError(reason=_(
                "host category cannot be set to 'all' "
                "while there are allowed hosts"))
        if is_all(options, 'servicecategory') and 'memberservice' in entry_attrs:
            raise errors.MutuallyExclusiveError(reason=_(
                "service category cannot be set to 'all' "
                "while there are allowed services"))
        return dn


@register()
class caacl_find(LDAPSearch):
    __doc__ = _('Search for CA ACLs.')

    msg_summary = ngettext(
        '%(count)d CA ACL matched', '%(count)d CA ACLs matched', 0
    )


@register()
class caacl_show(LDAPRetrieve):
    __doc__ = _('Display the properties of a CA ACL.')


@register()
class caacl_enable(LDAPQuery):
    __doc__ = _('Enable a CA ACL.')

    msg_summary = _('Enabled CA ACL "%(value)s"')
    has_output = output.standard_value

    def execute(self, cn, **options):
        ldap = self.obj.backend

        dn = self.obj.get_dn(cn)
        try:
            entry_attrs = ldap.get_entry(dn, ['ipaenabledflag'])
        except errors.NotFound:
            self.obj.handle_not_found(cn)

        entry_attrs['ipaenabledflag'] = ['TRUE']

        try:
            ldap.update_entry(entry_attrs)
        except errors.EmptyModlist:
            pass

        return dict(
            result=True,
            value=pkey_to_value(cn, options),
        )


@register()
class caacl_disable(LDAPQuery):
    __doc__ = _('Disable a CA ACL.')

    msg_summary = _('Disabled CA ACL "%(value)s"')
    has_output = output.standard_value

    def execute(self, cn, **options):
        ldap = self.obj.backend

        dn = self.obj.get_dn(cn)
        try:
            entry_attrs = ldap.get_entry(dn, ['ipaenabledflag'])
        except errors.NotFound:
            self.obj.handle_not_found(cn)

        entry_attrs['ipaenabledflag'] = ['FALSE']

        try:
            ldap.update_entry(entry_attrs)
        except errors.EmptyModlist:
            pass

        return dict(
            result=True,
            value=pkey_to_value(cn, options),
        )


@register()
class caacl_add_user(LDAPAddMember):
    __doc__ = _('Add users and groups to a CA ACL.')

    member_attributes = ['memberuser']
    member_count_out = (
        _('%i user or group added.'),
        _('%i users or groups added.'))

    def pre_callback(self, ldap, dn, found, not_found, *keys, **options):
        assert isinstance(dn, DN)
        try:
            entry_attrs = ldap.get_entry(dn, self.obj.default_attributes)
            dn = entry_attrs.dn
        except errors.NotFound:
            self.obj.handle_not_found(*keys)
        if is_all(entry_attrs, 'usercategory'):
            raise errors.MutuallyExclusiveError(
                reason=_("users cannot be added when user category='all'"))
        return dn


@register()
class caacl_remove_user(LDAPRemoveMember):
    __doc__ = _('Remove users and groups from a CA ACL.')

    member_attributes = ['memberuser']
    member_count_out = (
        _('%i user or group removed.'),
        _('%i users or groups removed.'))


@register()
class caacl_add_host(LDAPAddMember):
    __doc__ = _('Add target hosts and hostgroups to a CA ACL.')

    member_attributes = ['memberhost']
    member_count_out = (
        _('%i host or hostgroup added.'),
        _('%i hosts or hostgroups added.'))

    def pre_callback(self, ldap, dn, found, not_found, *keys, **options):
        assert isinstance(dn, DN)
        try:
            entry_attrs = ldap.get_entry(dn, self.obj.default_attributes)
            dn = entry_attrs.dn
        except errors.NotFound:
            self.obj.handle_not_found(*keys)
        if is_all(entry_attrs, 'hostcategory'):
            raise errors.MutuallyExclusiveError(
                reason=_("hosts cannot be added when host category='all'"))
        return dn


@register()
class caacl_remove_host(LDAPRemoveMember):
    __doc__ = _('Remove target hosts and hostgroups from a CA ACL.')

    member_attributes = ['memberhost']
    member_count_out = (
        _('%i host or hostgroup removed.'),
        _('%i hosts or hostgroups removed.'))


@register()
class caacl_add_service(LDAPAddMember):
    __doc__ = _('Add services to a CA ACL.')

    member_attributes = ['memberservice']
    member_count_out = (_('%i service added.'), _('%i services added.'))

    def pre_callback(self, ldap, dn, found, not_found, *keys, **options):
        assert isinstance(dn, DN)
        try:
            entry_attrs = ldap.get_entry(dn, self.obj.default_attributes)
            dn = entry_attrs.dn
        except errors.NotFound:
            self.obj.handle_not_found(*keys)
        if is_all(entry_attrs, 'servicecategory'):
            raise errors.MutuallyExclusiveError(reason=_(
                "services cannot be added when service category='all'"))
        return dn


@register()
class caacl_remove_service(LDAPRemoveMember):
    __doc__ = _('Remove services from a CA ACL.')

    member_attributes = ['memberservice']
    member_count_out = (_('%i service removed.'), _('%i services removed.'))


caacl_output_params = global_output_params + (
    Str('ipamembercertprofile',
        label=_('Failed profiles'),
    ),
    Str('ipamemberca',
        label=_('Failed CAs'),
    ),
)


@register()
class caacl_add_profile(LDAPAddMember):
    __doc__ = _('Add profiles to a CA ACL.')

    has_output_params = caacl_output_params

    member_attributes = ['ipamembercertprofile']
    member_count_out = (_('%i profile added.'), _('%i profiles added.'))

    def pre_callback(self, ldap, dn, found, not_found, *keys, **options):
        assert isinstance(dn, DN)
        try:
            entry_attrs = ldap.get_entry(dn, self.obj.default_attributes)
            dn = entry_attrs.dn
        except errors.NotFound:
            self.obj.handle_not_found(*keys)
        if is_all(entry_attrs, 'ipacertprofilecategory'):
            raise errors.MutuallyExclusiveError(reason=_(
                "profiles cannot be added when profile category='all'"))
        return dn


@register()
class caacl_remove_profile(LDAPRemoveMember):
    __doc__ = _('Remove profiles from a CA ACL.')

    has_output_params = caacl_output_params

    member_attributes = ['ipamembercertprofile']
    member_count_out = (_('%i profile removed.'), _('%i profiles removed.'))


@register()
class caacl_add_ca(LDAPAddMember):
    __doc__ = _('Add CAs to a CA ACL.')

    has_output_params = caacl_output_params

    member_attributes = ['ipamemberca']
    member_count_out = (_('%i CA added.'), _('%i CAs added.'))

    def pre_callback(self, ldap, dn, found, not_found, *keys, **options):
        assert isinstance(dn, DN)
        try:
            entry_attrs = ldap.get_entry(dn, self.obj.default_attributes)
            dn = entry_attrs.dn
        except errors.NotFound:
            self.obj.handle_not_found(*keys)
        if is_all(entry_attrs, 'ipacacategory'):
            raise errors.MutuallyExclusiveError(reason=_(
                "CAs cannot be added when CA category='all'"))
        return dn


@register()
class caacl_remove_ca(LDAPRemoveMember):
    __doc__ = _('Remove CAs from a CA ACL.')

    has_output_params = caacl_output_params

    member_attributes = ['ipamemberca']
    member_count_out = (_('%i CA removed.'), _('%i CAs removed.'))