OpenID Connect RP support for customer accounts

src/pretix/base/customersso/__init__.py

@@ -0,0 +1,21 @@
+#
+# This file is part of pretix (Community Edition).
+#
+# Copyright (C) 2014-2020 Raphael Michel and contributors
+# Copyright (C) 2020-2021 rami.io GmbH and contributors
+#
+# This program is free software: you can redistribute it and/or modify it under the terms of the GNU Affero General
+# Public License as published by the Free Software Foundation in version 3 of the License.
+#
+# ADDITIONAL TERMS APPLY: Pursuant to Section 7 of the GNU Affero General Public License, additional terms are
+# applicable granting you additional permissions and placing additional restrictions on your usage of this software.
+# Please refer to the pretix LICENSE file to obtain the full terms applicable to this work. If you did not receive
+# this file, see <https://pretix.eu/about/en/license>.
+#
+# 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 Affero General Public License for more
+# details.
+#
+# You should have received a copy of the GNU Affero General Public License along with this program.  If not, see
+# <https://www.gnu.org/licenses/>.
+#

src/pretix/base/customersso/oidc.py

@@ -0,0 +1,207 @@
+#
+# This file is part of pretix (Community Edition).
+#
+# Copyright (C) 2014-2020 Raphael Michel and contributors
+# Copyright (C) 2020-2021 rami.io GmbH and contributors
+#
+# This program is free software: you can redistribute it and/or modify it under the terms of the GNU Affero General
+# Public License as published by the Free Software Foundation in version 3 of the License.
+#
+# ADDITIONAL TERMS APPLY: Pursuant to Section 7 of the GNU Affero General Public License, additional terms are
+# applicable granting you additional permissions and placing additional restrictions on your usage of this software.
+# Please refer to the pretix LICENSE file to obtain the full terms applicable to this work. If you did not receive
+# this file, see <https://pretix.eu/about/en/license>.
+#
+# 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 Affero General Public License for more
+# details.
+#
+# You should have received a copy of the GNU Affero General Public License along with this program.  If not, see
+# <https://www.gnu.org/licenses/>.
+#
+import logging
+from urllib.parse import urlencode, urljoin
+
+import requests
+from django.core.exceptions import ValidationError
+from django.utils.translation import gettext_lazy as _
+from requests import RequestException
+
+logger = logging.getLogger(__name__)
+
+
+def _urljoin(base, path):
+    if not base.endswith("/"):
+        base += "/"
+    return urljoin(base, path)
+
+
+def oidc_validate_and_complete_config(config):
+    for k in ("base_url", "client_id", "client_secret", "uid_field", "email_field", "scope"):
+        if not config.get(k):
+            raise ValidationError(_('Configuration option "{name}" is missing.').format(name=k))
+
+    conf_url = _urljoin(config["base_url"], ".well-known/openid-configuration")
+    try:
+        resp = requests.get(conf_url, timeout=10)
+        resp.raise_for_status()
+        provider_config = resp.json()
+    except RequestException as e:
+        raise ValidationError(_('Unable to retrieve configuration from "{url}". Error message: "{error}".').format(
+            url=conf_url,
+            error=str(e)
+        ))
+    except ValueError as e:
+        raise ValidationError(_('Unable to retrieve configuration from "{url}". Error message: "{error}".').format(
+            url=conf_url,
+            error=str(e)
+        ))
+
+    if not provider_config.get("authorization_endpoint"):
+        raise ValidationError(_('Incompatible SSO provider: "{error}".').format(
+            error="authorization_endpoint not set"
+        ))
+
+    if not provider_config.get("userinfo_endpoint"):
+        raise ValidationError(_('Incompatible SSO provider: "{error}".').format(
+            error="userinfo_endpoint not set"
+        ))
+
+    if not provider_config.get("token_endpoint"):
+        raise ValidationError(_('Incompatible SSO provider: "{error}".').format(
+            error="token_endpoint not set"
+        ))
+
+    if "code" not in provider_config.get("response_types_supported", []):
+        raise ValidationError(_('Incompatible SSO provider: "{error}".').format(
+            error=f"provider supports response types {','.join(provider_config.get('response_types_supported', []))}, but we only support 'code'."
+        ))
+
+    if "query" not in provider_config.get("response_modes_supported", ["query", "fragment"]):
+        raise ValidationError(_('Incompatible SSO provider: "{error}".').format(
+            error=f"provider supports response modes {','.join(provider_config.get('response_modes_supported', []))}, but we only support 'query'."
+        ))
+
+    if "authorization_code" not in provider_config.get("grant_types_supported", ["authorization_code", "implicit"]):
+        raise ValidationError(_('Incompatible SSO provider: "{error}".').format(
+            error=f"provider supports grant types {','.join(provider_config.get('grant_types_supported', ''))}, but we only support 'authorization_code'."
+        ))
+
+    if "openid" not in config["scope"].split(" "):
+        raise ValidationError(
+            _('You are not requesting "{scope}".').format(
+                scope="openid",
+            ))
+
+    for scope in config["scope"].split(" "):
+        if scope not in provider_config.get("scopes_supported", []):
+            raise ValidationError(_('You are requesting scope "{scope}" but provider only supports these: {scopes}.').format(
+                scope=scope,
+                scopes=", ".join(provider_config.get("scopes_supported", []))
+            ))
+
+    for k, v in config.items():
+        if k.endswith('_field') and v:
+            if v not in provider_config.get("claims_supported", []):  # https://openid.net/specs/openid-connect-core-1_0.html#UserInfo
+                raise ValidationError(_('You are requesting field "{field}" but provider only supports these: {fields}.').format(
+                    field=v,
+                    fields=", ".join(provider_config.get("claims_supported", []))
+                ))
+
+    config['provider_config'] = provider_config
+    return config
+
+
+def oidc_authorize_url(provider, state, redirect_uri):
+    endpoint = provider.configuration['provider_config']['authorization_endpoint']
+    params = {
+        # https://datatracker.ietf.org/doc/html/rfc6749#section-4.1.1
+        # https://openid.net/specs/openid-connect-core-1_0.html#AuthorizationEndpoint
+        'response_type': 'code',
+        'client_id': provider.configuration['client_id'],
+        'scope': provider.configuration['scope'],
+        'state': state,
+        'redirect_uri': redirect_uri,
+    }
+    return endpoint + '?' + urlencode(params)
+
+
+def oidc_validate_authorization(provider, code, redirect_uri):
+    endpoint = provider.configuration['provider_config']['token_endpoint']
+    params = {
+        # https://datatracker.ietf.org/doc/html/rfc6749#section-4.1.3
+        # https://openid.net/specs/openid-connect-core-1_0.html#TokenEndpoint
+        'grant_type': 'authorization_code',
+        'code': code,
+        'redirect_uri': redirect_uri,
+    }
+    try:
+        resp = requests.post(
+            endpoint,
+            data=params,
+            headers={
+                'Accept': 'application/json',
+            },
+            auth=(provider.configuration['client_id'], provider.configuration['client_secret']),
+        )
+        resp.raise_for_status()
+        data = resp.json()
+    except RequestException:
+        logger.exception('Could not retrieve authorization token')
+        raise ValidationError(
+            _('Login was not successful. Error message: "{error}".').format(
+                error='could not reach login provider',
+            )
+        )
+
+    if 'access_token' not in data:
+        raise ValidationError(
+            _('Login was not successful. Error message: "{error}".').format(
+                error='access token missing',
+            )
+        )
+
+    endpoint = provider.configuration['provider_config']['userinfo_endpoint']
+    try:
+        # https://openid.net/specs/openid-connect-core-1_0.html#UserInfo
+        resp = requests.get(
+            endpoint,
+            headers={
+                'Authorization': f'Bearer {data["access_token"]}'
+            },
+        )
+        resp.raise_for_status()
+        userinfo = resp.json()
+    except RequestException:
+        logger.exception('Could not retrieve user info')
+        raise ValidationError(
+            _('Login was not successful. Error message: "{error}".').format(
+                error='could not fetch user info',
+            )
+        )
+
+    if 'email_verified' in userinfo and not userinfo['email_verified']:
+        # todo: how universal is this, do we need to make this configurable?
+        raise ValidationError(_('The email address on this account is not yet verified. Please first confirm the '
+                                'email address in your customer account.'))
+
+    profile = {}
+    for k, v in provider.configuration.items():
+        if k.endswith('_field'):
+            profile[k[:-6]] = userinfo.get(v)
+
+    if not profile.get('uid'):
+        raise ValidationError(
+            _('Login was not successful. Error message: "{error}".').format(
+                error='could not fetch user id',
+            )
+        )
+
+    if not profile.get('email'):
+        raise ValidationError(
+            _('Login was not successful. Error message: "{error}".').format(
+                error='could not fetch user email',
+            )
+        )
+
+    return profile

src/pretix/base/migrations/0219_auto_20220706_0913.py

@@ -0,0 +1,38 @@
+# Generated by Django 3.2.12 on 2022-07-06 09:13
+
+import django.db.models.deletion
+import i18nfield.fields
+from django.db import migrations, models
+
+import pretix.base.models.base
+
+
+class Migration(migrations.Migration):
+
+    dependencies = [
+        ('pretixbase', '0218_checkinlist_addon_match'),
+    ]
+
+    operations = [
+        migrations.CreateModel(
+            name='CustomerSSOProvider',
+            fields=[
+                ('id', models.BigAutoField(primary_key=True, serialize=False)),
+                ('name', i18nfield.fields.I18nCharField(max_length=200)),
+                ('is_active', models.BooleanField(default=True)),
+                ('button_label', i18nfield.fields.I18nCharField(max_length=200)),
+                ('method', models.CharField(max_length=190)),
+                ('configuration', models.JSONField()),
+                ('organizer', models.ForeignKey(on_delete=django.db.models.deletion.CASCADE, related_name='sso_providers', to='pretixbase.organizer')),
+            ],
+            options={
+                'abstract': False,
+            },
+            bases=(models.Model, pretix.base.models.base.LoggingMixin),
+        ),
+        migrations.AddField(
+            model_name='customer',
+            name='provider',
+            field=models.ForeignKey(null=True, on_delete=django.db.models.deletion.CASCADE, related_name='customers', to='pretixbase.customerssoprovider'),
+        ),
+    ]

src/pretix/base/models/customers.py

@@ -30,6 +30,7 @@ from django.db.models import F, Q
 from django.utils.crypto import get_random_string, salted_hmac
 from django.utils.translation import gettext_lazy as _, pgettext_lazy
 from django_scopes import ScopedManager, scopes_disabled
+from i18nfield.fields import I18nCharField
 from phonenumber_field.modelfields import PhoneNumberField
 
 from pretix.base.banlist import banned
@@ -39,12 +40,42 @@ from pretix.base.settings import PERSON_NAME_SCHEMES
 from pretix.helpers.countries import FastCountryField
 
 
+class CustomerSSOProvider(LoggedModel):
+    METHOD_OIDC = 'oidc'
+    METHODS = (
+        (METHOD_OIDC, 'OpenID Connect'),
+    )
+
+    id = models.BigAutoField(primary_key=True)
+    organizer = models.ForeignKey(Organizer, related_name='sso_providers', on_delete=models.CASCADE)
+    name = I18nCharField(
+        max_length=200,
+        verbose_name=_("Provider name"),
+    )
+    is_active = models.BooleanField(default=True, verbose_name=_('Active'))
+    button_label = I18nCharField(
+        max_length=200,
+        verbose_name=_("Login button label"),
+    )
+    method = models.CharField(
+        max_length=190,
+        verbose_name=_("Single-sign-on method"),
+        null=False, blank=False,
+        choices=METHODS,
+    )
+    configuration = models.JSONField()
+
+    def allow_delete(self):
+        return not self.customers.exists()
+
+
 class Customer(LoggedModel):
     """
     Represents a registered customer of an organizer.
     """
     id = models.BigAutoField(primary_key=True)
     organizer = models.ForeignKey(Organizer, related_name='customers', on_delete=models.CASCADE)
+    provider = models.ForeignKey(CustomerSSOProvider, related_name='customers', on_delete=models.PROTECT, null=True, blank=True)
     identifier = models.CharField(
         max_length=190,
         db_index=True,

src/pretix/base/settings.py

@@ -146,6 +146,17 @@ DEFAULTS = {
                         "advanced features like memberships.")
         )
     },
+    'customer_accounts_native': {
+        'default': 'True',
+        'type': bool,
+        'form_class': forms.BooleanField,
+        'serializer_class': serializers.BooleanField,
+        'form_kwargs': dict(
+            label=_("Allow customers to log in with email address and password"),
+            help_text=_("If disabled, you will need to connect one or more single-sign-on providers."),
+            widget=forms.CheckboxInput(attrs={'data-display-dependency': '#id_settings-customer_accounts'}),
+        )
+    },
     'customer_accounts_link_by_email': {
         'default': 'False',
         'type': bool,