Fix metadata overall limits bug

Currently metadata limits are checked on a per request basis. If
multiple requests are sent within the per request limits, it is
possible to exceed the overall limits.  This patch adds an overall
metadata check to ensure that multiple requests to add metadata to
an account/container will check overall limits before adding
the additional metadata.

Change-Id: Ib9401a4ee05a9cb737939541bd9b84e8dc239c70
Closes-Bug: 1365350

7 files changed, 175 insertions, 7 deletions

diff --git a/swift/account/server.py b/swift/account/server.py
index 3bdf37f15..cf160e9e2 100644
--- a/swift/account/server.py
+++ b/swift/account/server.py
@@ -156,7 +156,7 @@ class AccountController(object):
                             for key, value in req.headers.iteritems()
                             if is_sys_or_user_meta('account', key))
             if metadata:
-                broker.update_metadata(metadata)
+                broker.update_metadata(metadata, validate_metadata=True)
             if created:
                 return HTTPCreated(request=req)
             else:
@@ -249,7 +249,7 @@ class AccountController(object):
                         for key, value in req.headers.iteritems()
                         if is_sys_or_user_meta('account', key))
         if metadata:
-            broker.update_metadata(metadata)
+            broker.update_metadata(metadata, validate_metadata=True)
         return HTTPNoContent(request=req)
 
     def __call__(self, env, start_response):
diff --git a/swift/common/constraints.py b/swift/common/constraints.py
index b41239e6f..eacc6c8d3 100644
--- a/swift/common/constraints.py
+++ b/swift/common/constraints.py
@@ -101,7 +101,10 @@ FORMAT2CONTENT_TYPE = {'plain': 'text/plain', 'json': 'application/json',
 
 def check_metadata(req, target_type):
     """
-    Check metadata sent in the request headers.
+    Check metadata sent in the request headers.  This should only check
+    that the metadata in the request given is valid.  Checks against
+    account/container overall metadata should be forwarded on to its
+    respective server to be checked.
 
     :param req: request object
     :param target_type: str: one of: object, container, or account: indicates
diff --git a/swift/common/db.py b/swift/common/db.py
index daad589ed..4c325b1ed 100644
--- a/swift/common/db.py
+++ b/swift/common/db.py
@@ -30,9 +30,11 @@ from tempfile import mkstemp
 from eventlet import sleep, Timeout
 import sqlite3
 
+from swift.common.constraints import MAX_META_COUNT, MAX_META_OVERALL_SIZE
 from swift.common.utils import json, Timestamp, renamer, \
     mkdirs, lock_parent_directory, fallocate
 from swift.common.exceptions import LockTimeout
+from swift.common.swob import HTTPBadRequest
 
 
 #: Whether calls will be made to preallocate disk space for database files.
@@ -719,7 +721,35 @@ class DatabaseBroker(object):
             metadata = {}
         return metadata
 
-    def update_metadata(self, metadata_updates):
+    @staticmethod
+    def validate_metadata(metadata):
+        """
+        Validates that metadata_falls within acceptable limits.
+
+        :param metadata: to be validated
+        :raises: HTTPBadRequest if MAX_META_COUNT or MAX_META_OVERALL_SIZE
+                 is exceeded
+        """
+        meta_count = 0
+        meta_size = 0
+        for key, (value, timestamp) in metadata.iteritems():
+            key = key.lower()
+            if value != '' and (key.startswith('x-account-meta') or
+                                key.startswith('x-container-meta')):
+                prefix = 'x-account-meta-'
+                if key.startswith('x-container-meta-'):
+                    prefix = 'x-container-meta-'
+                key = key[len(prefix):]
+                meta_count = meta_count + 1
+                meta_size = meta_size + len(key) + len(value)
+        if meta_count > MAX_META_COUNT:
+            raise HTTPBadRequest('Too many metadata items; max %d'
+                                 % MAX_META_COUNT)
+        if meta_size > MAX_META_OVERALL_SIZE:
+            raise HTTPBadRequest('Total metadata too large; max %d'
+                                 % MAX_META_OVERALL_SIZE)
+
+    def update_metadata(self, metadata_updates, validate_metadata=False):
         """
         Updates the metadata dict for the database. The metadata dict values
         are tuples of (value, timestamp) where the timestamp indicates when
@@ -752,6 +782,8 @@ class DatabaseBroker(object):
                 value, timestamp = value_timestamp
                 if key not in md or timestamp > md[key][1]:
                     md[key] = value_timestamp
+            if validate_metadata:
+                DatabaseBroker.validate_metadata(md)
             conn.execute('UPDATE %s_stat SET metadata = ?' % self.db_type,
                          (json.dumps(md),))
             conn.commit()
diff --git a/swift/container/server.py b/swift/container/server.py
index 76b7771ac..6ef713188 100644
--- a/swift/container/server.py
+++ b/swift/container/server.py
@@ -374,7 +374,7 @@ class ContainerController(object):
                         metadata['X-Container-Sync-To'][0] != \
                         broker.metadata['X-Container-Sync-To'][0]:
                     broker.set_x_container_sync_points(-1, -1)
-            broker.update_metadata(metadata)
+            broker.update_metadata(metadata, validate_metadata=True)
             resp = self.account_update(req, account, container, broker)
             if resp:
                 return resp
@@ -551,7 +551,7 @@ class ContainerController(object):
                         metadata['X-Container-Sync-To'][0] != \
                         broker.metadata['X-Container-Sync-To'][0]:
                     broker.set_x_container_sync_points(-1, -1)
-            broker.update_metadata(metadata)
+            broker.update_metadata(metadata, validate_metadata=True)
         return HTTPNoContent(request=req)
 
     def __call__(self, env, start_response):
diff --git a/test/functional/test_account.py b/test/functional/test_account.py
index a739259fc..30a8e7418 100755
--- a/test/functional/test_account.py
+++ b/test/functional/test_account.py
@@ -774,6 +774,21 @@ class TestAccount(unittest.TestCase):
         resp.read()
         self.assertEqual(resp.status, 400)
 
+    def test_bad_metadata2(self):
+        if tf.skip:
+            raise SkipTest
+
+        def post(url, token, parsed, conn, extra_headers):
+            headers = {'X-Auth-Token': token}
+            headers.update(extra_headers)
+            conn.request('POST', parsed.path, '', headers)
+            return check_response(conn)
+
+        # TODO: Find the test that adds these and remove them.
+        headers = {'x-remove-account-meta-temp-url-key': 'remove',
+                   'x-remove-account-meta-temp-url-key-2': 'remove'}
+        resp = retry(post, headers)
+
         headers = {}
         for x in xrange(self.max_meta_count):
             headers['X-Account-Meta-%d' % x] = 'v'
@@ -787,6 +802,16 @@ class TestAccount(unittest.TestCase):
         resp.read()
         self.assertEqual(resp.status, 400)
 
+    def test_bad_metadata3(self):
+        if tf.skip:
+            raise SkipTest
+
+        def post(url, token, parsed, conn, extra_headers):
+            headers = {'X-Auth-Token': token}
+            headers.update(extra_headers)
+            conn.request('POST', parsed.path, '', headers)
+            return check_response(conn)
+
         headers = {}
         header_value = 'k' * self.max_meta_value_length
         size = 0
diff --git a/test/functional/test_container.py b/test/functional/test_container.py
index bfd41fb10..d7896a42e 100755
--- a/test/functional/test_container.py
+++ b/test/functional/test_container.py
@@ -401,6 +401,16 @@ class TestContainer(unittest.TestCase):
         resp.read()
         self.assertEqual(resp.status, 400)
 
+    def test_POST_bad_metadata2(self):
+        if tf.skip:
+            raise SkipTest
+
+        def post(url, token, parsed, conn, extra_headers):
+            headers = {'X-Auth-Token': token}
+            headers.update(extra_headers)
+            conn.request('POST', parsed.path + '/' + self.name, '', headers)
+            return check_response(conn)
+
         headers = {}
         for x in xrange(self.max_meta_count):
             headers['X-Container-Meta-%d' % x] = 'v'
@@ -414,6 +424,16 @@ class TestContainer(unittest.TestCase):
         resp.read()
         self.assertEqual(resp.status, 400)
 
+    def test_POST_bad_metadata3(self):
+        if tf.skip:
+            raise SkipTest
+
+        def post(url, token, parsed, conn, extra_headers):
+            headers = {'X-Auth-Token': token}
+            headers.update(extra_headers)
+            conn.request('POST', parsed.path + '/' + self.name, '', headers)
+            return check_response(conn)
+
         headers = {}
         header_value = 'k' * self.max_meta_value_length
         size = 0
diff --git a/test/unit/common/test_db.py b/test/unit/common/test_db.py
index e0c164de9..d4f982854 100644
--- a/test/unit/common/test_db.py
+++ b/test/unit/common/test_db.py
@@ -32,11 +32,14 @@ from mock import patch, MagicMock
 from eventlet.timeout import Timeout
 
 import swift.common.db
+from swift.common.constraints import \
+    MAX_META_VALUE_LENGTH, MAX_META_COUNT, MAX_META_OVERALL_SIZE
 from swift.common.db import chexor, dict_factory, get_db_connection, \
     DatabaseBroker, DatabaseConnectionError, DatabaseAlreadyExists, \
     GreenDBConnection, PICKLE_PROTOCOL
 from swift.common.utils import normalize_timestamp, mkdirs, json, Timestamp
 from swift.common.exceptions import LockTimeout
+from swift.common.swob import HTTPException
 
 from test.unit import with_tempdir
 
@@ -655,7 +658,7 @@ class TestDatabaseBroker(unittest.TestCase):
             conn.execute('CREATE TABLE test (one TEXT)')
             conn.execute('CREATE TABLE test_stat (id TEXT)')
             conn.execute('INSERT INTO test_stat (id) VALUES (?)',
-                        (str(uuid4),))
+                         (str(uuid4),))
             conn.execute('INSERT INTO test (one) VALUES ("1")')
             conn.commit()
         stub_called = [False]
@@ -1107,6 +1110,91 @@ class TestDatabaseBroker(unittest.TestCase):
                           [first_value, first_timestamp])
         self.assert_('Second' not in broker.metadata)
 
+    @patch.object(DatabaseBroker, 'validate_metadata')
+    def test_validate_metadata_is_called_from_update_metadata(self, mock):
+        broker = self.get_replication_info_tester(metadata=True)
+        first_timestamp = normalize_timestamp(1)
+        first_value = '1'
+        metadata = {'First': [first_value, first_timestamp]}
+        broker.update_metadata(metadata, validate_metadata=True)
+        self.assertTrue(mock.called)
+
+    @patch.object(DatabaseBroker, 'validate_metadata')
+    def test_validate_metadata_is_not_called_from_update_metadata(self, mock):
+        broker = self.get_replication_info_tester(metadata=True)
+        first_timestamp = normalize_timestamp(1)
+        first_value = '1'
+        metadata = {'First': [first_value, first_timestamp]}
+        broker.update_metadata(metadata)
+        self.assertFalse(mock.called)
+
+    def test_metadata_with_max_count(self):
+        metadata = {}
+        for c in xrange(MAX_META_COUNT):
+            key = 'X-Account-Meta-F{0}'.format(c)
+            metadata[key] = ('B', normalize_timestamp(1))
+        key = 'X-Account-Meta-Foo'.format(c)
+        metadata[key] = ('', normalize_timestamp(1))
+        try:
+            DatabaseBroker.validate_metadata(metadata)
+        except HTTPException:
+            self.fail('Unexpected HTTPException')
+
+    def test_metadata_raises_exception_over_max_count(self):
+        metadata = {}
+        for c in xrange(MAX_META_COUNT + 1):
+            key = 'X-Account-Meta-F{0}'.format(c)
+            metadata[key] = ('B', normalize_timestamp(1))
+        message = ''
+        try:
+            DatabaseBroker.validate_metadata(metadata)
+        except HTTPException as e:
+            message = str(e)
+        self.assertEqual(message, '400 Bad Request')
+
+    def test_metadata_with_max_overall_size(self):
+        metadata = {}
+        metadata_value = 'v' * MAX_META_VALUE_LENGTH
+        size = 0
+        x = 0
+        while size < (MAX_META_OVERALL_SIZE - 4
+                      - MAX_META_VALUE_LENGTH):
+            size += 4 + MAX_META_VALUE_LENGTH
+            metadata['X-Account-Meta-%04d' % x] = (metadata_value,
+                                                   normalize_timestamp(1))
+            x += 1
+        if MAX_META_OVERALL_SIZE - size > 1:
+            metadata['X-Account-Meta-k'] = (
+                'v' * (MAX_META_OVERALL_SIZE - size - 1),
+                normalize_timestamp(1))
+        try:
+            DatabaseBroker.validate_metadata(metadata)
+        except HTTPException:
+            self.fail('Unexpected HTTPException')
+
+    def test_metadata_raises_exception_over_max_overall_size(self):
+        metadata = {}
+        metadata_value = 'k' * MAX_META_VALUE_LENGTH
+        size = 0
+        x = 0
+        while size < (MAX_META_OVERALL_SIZE - 4
+                      - MAX_META_VALUE_LENGTH):
+            size += 4 + MAX_META_VALUE_LENGTH
+            metadata['X-Account-Meta-%04d' % x] = (metadata_value,
+                                                   normalize_timestamp(1))
+            x += 1
+        if MAX_META_OVERALL_SIZE - size > 1:
+            metadata['X-Account-Meta-k'] = (
+                'v' * (MAX_META_OVERALL_SIZE - size - 1),
+                normalize_timestamp(1))
+        metadata['X-Account-Meta-k2'] = ('v', normalize_timestamp(1))
+        message = ''
+        try:
+            DatabaseBroker.validate_metadata(metadata)
+        except HTTPException as e:
+            message = str(e)
+        self.assertEqual(message, '400 Bad Request')
+
 
 if __name__ == '__main__':
     unittest.main()