summaryrefslogtreecommitdiffstats
path: root/ipsilon/providers/saml2/auth.py
blob: 95751aa3a0ef8585115c8a8672459ed1ef90688b (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
# Copyright (C) 2014  Simo Sorce <simo@redhat.com>
#
# see file 'COPYING' for use and warranty information
#
# This program is free software; you can redistribute it and/or modify
# it under the terms of the GNU General Public License as published by
# the Free Software Foundation, either version 3 of the License, or
# (at your option) any later version.
#
# This program 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 General Public License for more details.
#
# You should have received a copy of the GNU General Public License
# along with this program.  If not, see <http://www.gnu.org/licenses/>.

from ipsilon.providers.common import ProviderPageBase, ProviderException
from ipsilon.providers.common import AuthenticationError, InvalidRequest
from ipsilon.providers.saml2.provider import ServiceProvider
from ipsilon.providers.saml2.provider import InvalidProviderId
from ipsilon.providers.saml2.provider import NameIdNotAllowed
from ipsilon.providers.saml2.sessions import SAMLSessionsContainer
from ipsilon.util.policy import Policy
from ipsilon.util.user import UserSession
from ipsilon.util.trans import Transaction
import cherrypy
import datetime
import lasso


class UnknownProvider(ProviderException):

    def __init__(self, message):
        super(UnknownProvider, self).__init__(message)
        self._debug(message)


class AuthenticateRequest(ProviderPageBase):

    def __init__(self, *args, **kwargs):
        super(AuthenticateRequest, self).__init__(*args, **kwargs)
        self.stage = 'init'
        self.trans = None

    def _preop(self, *args, **kwargs):
        try:
            # generate a new id or get current one
            self.trans = Transaction('saml2', **kwargs)
            if self.trans.cookie.value != self.trans.provider:
                self.debug('Invalid transaction, %s != %s' % (
                           self.trans.cookie.value, self.trans.provider))
        except Exception, e:  # pylint: disable=broad-except
            self.debug('Transaction initialization failed: %s' % repr(e))
            raise cherrypy.HTTPError(400, 'Invalid transaction id')

    def pre_GET(self, *args, **kwargs):
        self._preop(*args, **kwargs)

    def pre_POST(self, *args, **kwargs):
        self._preop(*args, **kwargs)

    def auth(self, login):
        try:
            self.saml2checks(login)
        except AuthenticationError, e:
            self.saml2error(login, e.code, e.message)
        return self.reply(login)

    def _parse_request(self, message):

        login = self.cfg.idp.get_login_handler()

        try:
            login.processAuthnRequestMsg(message)
        except (lasso.ProfileInvalidMsgError,
                lasso.ProfileMissingIssuerError), e:

            msg = 'Malformed Request %r [%r]' % (e, message)
            raise InvalidRequest(msg)

        except (lasso.ProfileInvalidProtocolprofileError,
                lasso.DsError), e:

            msg = 'Invalid SAML Request: %r (%r [%r])' % (login.request,
                                                          e, message)
            raise InvalidRequest(msg)

        except (lasso.ServerProviderNotFoundError,
                lasso.ProfileUnknownProviderError), e:

            msg = 'Invalid SP [%s] (%r [%r])' % (login.remoteProviderId,
                                                 e, message)
            raise UnknownProvider(msg)

        self._debug('SP %s requested authentication' % login.remoteProviderId)

        return login

    def saml2login(self, request):

        if not request:
            raise cherrypy.HTTPError(400,
                                     'SAML request token missing or empty')

        try:
            login = self._parse_request(request)
        except InvalidRequest, e:
            self._debug(str(e))
            raise cherrypy.HTTPError(400, 'Invalid SAML request token')
        except UnknownProvider, e:
            self._debug(str(e))
            raise cherrypy.HTTPError(400, 'Unknown Service Provider')
        except Exception, e:  # pylint: disable=broad-except
            self._debug(str(e))
            raise cherrypy.HTTPError(500)

        return login

    def saml2checks(self, login):

        us = UserSession()
        user = us.get_user()
        if user.is_anonymous:
            if self.stage == 'init':
                returl = '%s/saml2/SSO/Continue?%s' % (
                    self.basepath, self.trans.get_GET_arg())
                data = {'saml2_stage': 'auth',
                        'saml2_request': login.dump(),
                        'login_return': returl,
                        'login_target': login.remoteProviderId}
                self.trans.store(data)
                redirect = '%s/login?%s' % (self.basepath,
                                            self.trans.get_GET_arg())
                raise cherrypy.HTTPRedirect(redirect)
            else:
                raise AuthenticationError(
                    "Unknown user", lasso.SAML2_STATUS_CODE_AUTHN_FAILED)

        self._audit("Logged in user: %s [%s]" % (user.name, user.fullname))

        # We can wipe the transaction now, as this is the last step
        self.trans.wipe()

        # TODO: check if this is the first time this user access this SP
        # If required by user prefs, ask user for consent once and then
        # record it
        consent = True

        # TODO: check destination

        try:
            provider = ServiceProvider(self.cfg, login.remoteProviderId)
            nameidfmt = provider.get_valid_nameid(login.request.nameIdPolicy)
        except NameIdNotAllowed, e:
            raise AuthenticationError(
                str(e), lasso.SAML2_STATUS_CODE_INVALID_NAME_ID_POLICY)
        except InvalidProviderId, e:
            raise AuthenticationError(
                str(e), lasso.SAML2_STATUS_CODE_AUTHN_FAILED)

        # TODO: check login.request.forceAuthn

        login.validateRequestMsg(not user.is_anonymous, consent)

        authtime = datetime.datetime.utcnow()
        skew = datetime.timedelta(0, 60)
        authtime_notbefore = authtime - skew
        authtime_notafter = authtime + skew

        # TODO: get authentication type fnd name format from session
        # need to save which login manager authenticated and map it to a
        # saml2 authentication context
        authn_context = lasso.SAML2_AUTHN_CONTEXT_UNSPECIFIED

        timeformat = '%Y-%m-%dT%H:%M:%SZ'
        login.buildAssertion(authn_context,
                             authtime.strftime(timeformat),
                             None,
                             authtime_notbefore.strftime(timeformat),
                             authtime_notafter.strftime(timeformat))

        nameid = None
        if nameidfmt == lasso.SAML2_NAME_IDENTIFIER_FORMAT_PERSISTENT:
            # TODO map to something else ?
            nameid = provider.normalize_username(user.name)
        elif nameidfmt == lasso.SAML2_NAME_IDENTIFIER_FORMAT_TRANSIENT:
            # TODO map to something else ?
            nameid = provider.normalize_username(user.name)
        elif nameidfmt == lasso.SAML2_NAME_IDENTIFIER_FORMAT_KERBEROS:
            nameid = us.get_data('user', 'krb_principal_name')
        elif nameidfmt == lasso.SAML2_NAME_IDENTIFIER_FORMAT_EMAIL:
            nameid = us.get_user().email
            if not nameid:
                nameid = '%s@%s' % (user.name, self.cfg.default_email_domain)

        if nameid:
            login.assertion.subject.nameId.format = nameidfmt
            login.assertion.subject.nameId.content = nameid
        else:
            self.trans.wipe()
            raise AuthenticationError("Unavailable Name ID type",
                                      lasso.SAML2_STATUS_CODE_AUTHN_FAILED)

        if not login.assertion.attributeStatement:
            attrstat = lasso.Saml2AttributeStatement()
            login.assertion.attributeStatement = [attrstat]
        else:
            attrstat = login.assertion.attributeStatement[0]
        if not attrstat.attribute:
            attrstat.attribute = ()

        # Check attribute policy and perform mapping and filtering
        policy = Policy(self.cfg.default_attribute_mapping,
                        self.cfg.default_allowed_attributes)
        userattrs = us.get_user_attrs()
        mappedattrs, _ = policy.map_attributes(userattrs)
        attributes = policy.filter_attributes(mappedattrs)

        self.debug("%s's attributes: %s" % (user.name, attributes))

        for key in attributes:
            values = attributes[key]
            if isinstance(values, dict):
                continue
            if not isinstance(values, list):
                values = [values]
            for value in values:
                attr = lasso.Saml2Attribute()
                attr.name = key
                attr.nameFormat = lasso.SAML2_ATTRIBUTE_NAME_FORMAT_BASIC
                value = str(value).encode('utf-8')
                self.debug('value %s' % value)
                node = lasso.MiscTextNode.newWithString(value)
                node.textChild = True
                attrvalue = lasso.Saml2AttributeValue()
                attrvalue.any = [node]
                attr.attributeValue = [attrvalue]
                attrstat.attribute = attrstat.attribute + (attr,)

        self.debug('Assertion: %s' % login.assertion.dump())

        saml_sessions = us.get_provider_data('saml2')
        if saml_sessions is None:
            saml_sessions = SAMLSessionsContainer()

        session = saml_sessions.find_session_by_provider(
            login.remoteProviderId)
        if session:
            # TODO: something...
            self.debug('Login session for this user already exists!?')
            session.dump()

        lasso_session = lasso.Session()
        lasso_session.addAssertion(login.remoteProviderId, login.assertion)
        saml_sessions.add_session(login.assertion.id,
                                  login.remoteProviderId,
                                  lasso_session)
        us.save_provider_data('saml2', saml_sessions)

    def saml2error(self, login, code, message):
        status = lasso.Samlp2Status()
        status.statusCode = lasso.Samlp2StatusCode()
        status.statusCode.value = lasso.SAML2_STATUS_CODE_RESPONDER
        status.statusCode.statusCode = lasso.Samlp2StatusCode()
        status.statusCode.statusCode.value = code
        login.response.status = status

    def reply(self, login):
        if login.protocolProfile == lasso.LOGIN_PROTOCOL_PROFILE_BRWS_ART:
            # TODO
            raise cherrypy.HTTPError(501)
        elif login.protocolProfile == lasso.LOGIN_PROTOCOL_PROFILE_BRWS_POST:
            login.buildAuthnResponseMsg()
            self._debug('POSTing back to SP [%s]' % (login.msgUrl))
            context = {
                "title": 'Redirecting back to the web application',
                "action": login.msgUrl,
                "fields": [
                    [lasso.SAML2_FIELD_RESPONSE, login.msgBody],
                    [lasso.SAML2_FIELD_RELAYSTATE, login.msgRelayState],
                ],
                "submit": 'Return to application',
            }
            # pylint: disable=star-args
            return self._template('saml2/post_response.html', **context)

        else:
            raise cherrypy.HTTPError(500)