Add size validations to token controller.

Updates token controller so that it explicitly checks the max
size of userId, username, tenantId, tenantname, token, and password
before continuing with a request.

Previously, when used with the SQL keystone backend an unauthenticated
user could send in *really* large requests which would ultimately log
large SQL exceptions and could thus fill up keystone logs on the
disk.

Change-Id: Ie7e3a958829f99f080e66582bdf558cded70248c

4 files changed, 96 insertions, 14 deletions

diff --git a/keystone/config.py b/keystone/config.py
index e7f31394..40af2fd6 100644
--- a/keystone/config.py
+++ b/keystone/config.py
@@ -141,6 +141,9 @@ register_str('policy_file', default='policy.json')
 register_str('policy_default_rule', default=None)
 #default max request size is 112k
 register_int('max_request_body_size', default=114688)
+register_int('max_param_size', default=64)
+# we allow tokens to be a bit larger to accomidate PKI
+register_int('max_token_size', default=8192)
 
 # identity
 register_str('default_domain_id', group='identity', default='default')
diff --git a/keystone/exception.py b/keystone/exception.py
index fe978061..5060dbfd 100644
--- a/keystone/exception.py
+++ b/keystone/exception.py
@@ -84,6 +84,19 @@ class StringLengthExceeded(ValidationError):
     %(type)s(CHAR(%(length)d))."""
 
 
+class ValidationSizeError(Error):
+    """Request attribute %(attribute)s must be less than or equal to %(size)i.
+
+    The server could not comply with the request because the attribute
+    size is invalid (too large).
+
+    The client is assumed to be in error.
+
+    """
+    code = 400
+    title = 'Bad Request'
+
+
 class SecurityError(Error):
     """Avoids exposing details of security failures, unless in debug mode."""
 
diff --git a/keystone/token/controllers.py b/keystone/token/controllers.py
index 1b51b9a1..62134028 100644
--- a/keystone/token/controllers.py
+++ b/keystone/token/controllers.py
@@ -5,12 +5,13 @@ from keystone.common import cms
 from keystone.common import controller
 from keystone.common import dependency
 from keystone.common import logging
+from keystone.common import utils
 from keystone import config
 from keystone import exception
 from keystone.openstack.common import timeutils
 from keystone.token import core
 
-
+CONF = config.CONF
 LOG = logging.getLogger(__name__)
 
 
@@ -22,13 +23,13 @@ class ExternalAuthNotApplicable(Exception):
 @dependency.requires('catalog_api')
 class Auth(controller.V2Controller):
     def ca_cert(self, context, auth=None):
-        ca_file = open(config.CONF.signing.ca_certs, 'r')
+        ca_file = open(CONF.signing.ca_certs, 'r')
         data = ca_file.read()
         ca_file.close()
         return data
 
     def signing_cert(self, context, auth=None):
-        cert_file = open(config.CONF.signing.certfile, 'r')
+        cert_file = open(CONF.signing.certfile, 'r')
         data = cert_file.read()
         cert_file.close()
         return data
@@ -134,17 +135,17 @@ class Auth(controller.V2Controller):
         service_catalog = Auth.format_catalog(catalog_ref)
         token_data['access']['serviceCatalog'] = service_catalog
 
-        if config.CONF.signing.token_format == 'UUID':
+        if CONF.signing.token_format == 'UUID':
             token_id = uuid.uuid4().hex
-        elif config.CONF.signing.token_format == 'PKI':
+        elif CONF.signing.token_format == 'PKI':
             token_id = cms.cms_sign_token(json.dumps(token_data),
-                                          config.CONF.signing.certfile,
-                                          config.CONF.signing.keyfile)
+                                          CONF.signing.certfile,
+                                          CONF.signing.keyfile)
         else:
             raise exception.UnexpectedError(
                 'Invalid value for token_format: %s.'
                 '  Allowed values are PKI or UUID.' %
-                config.CONF.signing.token_format)
+                CONF.signing.token_format)
         try:
             self.token_api.create_token(
                 context, token_id, dict(key=token_id,
@@ -180,6 +181,9 @@ class Auth(controller.V2Controller):
                 attribute="id", target="token")
 
         old_token = auth['token']['id']
+        if len(old_token) > CONF.max_token_size:
+            raise exception.ValidationSizeError(attribute='token',
+                                                size=CONF.max_token_size)
 
         try:
             old_token_ref = self.token_api.get_token(context=context,
@@ -228,6 +232,10 @@ class Auth(controller.V2Controller):
                 attribute='password', target='passwordCredentials')
 
         password = auth['passwordCredentials']['password']
+        max_pw_size = utils.MAX_PASSWORD_LENGTH
+        if password and len(password) > max_pw_size:
+            raise exception.ValidationSizeError(attribute='password',
+                                                size=max_pw_size)
 
         if ("userId" not in auth['passwordCredentials'] and
                 "username" not in auth['passwordCredentials']):
@@ -236,7 +244,14 @@ class Auth(controller.V2Controller):
                 target='passwordCredentials')
 
         user_id = auth['passwordCredentials'].get('userId', None)
+        if user_id and len(user_id) > CONF.max_param_size:
+            raise exception.ValidationSizeError(attribute='userId',
+                                                size=CONF.max_param_size)
+
         username = auth['passwordCredentials'].get('username', '')
+        if len(username) > CONF.max_param_size:
+            raise exception.ValidationSizeError(attribute='username',
+                                                size=CONF.max_param_size)
 
         if username:
             try:
@@ -323,7 +338,15 @@ class Auth(controller.V2Controller):
         Returns a valid tenant_id if it exists, or None if not specified.
         """
         tenant_id = auth.get('tenantId', None)
+        if tenant_id and len(tenant_id) > CONF.max_param_size:
+            raise exception.ValidationSizeError(attribute='tenantId',
+                                                size=CONF.max_param_size)
+
         tenant_name = auth.get('tenantName', None)
+        if tenant_name and len(tenant_name) > CONF.max_param_size:
+            raise exception.ValidationSizeError(attribute='tenantName',
+                                                size=CONF.max_param_size)
+
         if tenant_name:
             try:
                 tenant_ref = self.identity_api.get_project_by_name(
@@ -410,8 +433,8 @@ class Auth(controller.V2Controller):
 
         if cms.is_ans1_token(token_id):
             data = json.loads(cms.cms_verify(cms.token_to_cms(token_id),
-                                             config.CONF.signing.certfile,
-                                             config.CONF.signing.ca_certs))
+                                             CONF.signing.certfile,
+                                             CONF.signing.ca_certs))
             data['access']['token']['user'] = data['access']['user']
             data['access']['token']['metadata'] = data['access']['metadata']
             if belongs_to:
@@ -482,8 +505,8 @@ class Auth(controller.V2Controller):
         data = {'revoked': tokens}
         json_data = json.dumps(data)
         signed_text = cms.cms_sign_text(json_data,
-                                        config.CONF.signing.certfile,
-                                        config.CONF.signing.keyfile)
+                                        CONF.signing.certfile,
+                                        CONF.signing.keyfile)
 
         return {'signed': signed_text}
 
diff --git a/tests/test_auth.py b/tests/test_auth.py
index 1ca248d0..e8583153 100644
--- a/tests/test_auth.py
+++ b/tests/test_auth.py
@@ -27,8 +27,8 @@ from keystone import token
 CONF = config.CONF
 
 
-def _build_user_auth(token=None, username=None,
-                     password=None, tenant_name=None):
+def _build_user_auth(token=None, user_id=None, username=None,
+                     password=None, tenant_id=None, tenant_name=None):
     """Build auth dictionary.
 
     It will create an auth dictionary based on all the arguments
@@ -41,10 +41,14 @@ def _build_user_auth(token=None, username=None,
         auth_json['passwordCredentials'] = {}
     if username is not None:
         auth_json['passwordCredentials']['username'] = username
+    if user_id is not None:
+        auth_json['passwordCredentials']['userId'] = user_id
     if password is not None:
         auth_json['passwordCredentials']['password'] = password
     if tenant_name is not None:
         auth_json['tenantName'] = tenant_name
+    if tenant_id is not None:
+        auth_json['tenantId'] = tenant_id
     return auth_json
 
 
@@ -121,6 +125,45 @@ class AuthBadRequests(AuthTest):
         self.assertRaises(exception.ValidationError, self.api.authenticate,
                           {}, {'auth': 'abcd'})
 
+    def test_authenticate_user_id_too_large(self):
+        """Verify sending large 'userId' raises the right exception."""
+        body_dict = _build_user_auth(user_id='0' * 65, username='FOO',
+                                     password='foo2')
+        self.assertRaises(exception.ValidationSizeError, self.api.authenticate,
+                          {}, body_dict)
+
+    def test_authenticate_username_too_large(self):
+        """Verify sending large 'username' raises the right exception."""
+        body_dict = _build_user_auth(username='0' * 65, password='foo2')
+        self.assertRaises(exception.ValidationSizeError, self.api.authenticate,
+                          {}, body_dict)
+
+    def test_authenticate_tenant_id_too_large(self):
+        """Verify sending large 'tenantId' raises the right exception."""
+        body_dict = _build_user_auth(username='FOO', password='foo2',
+                                     tenant_id='0' * 65)
+        self.assertRaises(exception.ValidationSizeError, self.api.authenticate,
+                          {}, body_dict)
+
+    def test_authenticate_tenant_name_too_large(self):
+        """Verify sending large 'tenantName' raises the right exception."""
+        body_dict = _build_user_auth(username='FOO', password='foo2',
+                                     tenant_name='0' * 65)
+        self.assertRaises(exception.ValidationSizeError, self.api.authenticate,
+                          {}, body_dict)
+
+    def test_authenticate_token_too_large(self):
+        """Verify sending large 'token' raises the right exception."""
+        body_dict = _build_user_auth(token={'id': '0' * 8193})
+        self.assertRaises(exception.ValidationSizeError, self.api.authenticate,
+                          {}, body_dict)
+
+    def test_authenticate_password_too_large(self):
+        """Verify sending large 'password' raises the right exception."""
+        body_dict = _build_user_auth(username='FOO', password='0' * 8193)
+        self.assertRaises(exception.ValidationSizeError, self.api.authenticate,
+                          {}, body_dict)
+
 
 class AuthWithToken(AuthTest):
     def setUp(self):