Namespace_veth: Add funtionality for network namespace, veth ports

Adds functionality for network namespaces and veth/peer ports
to connect the namespaces. The namespaces are tracked outside
of default Linux namespaces to prevent possible disruption of
work outside of VSPerf where a user may create a namespace and
the cleanup code deletes it. The cleanup code only removes
namespaces and veth ports created inside the testcase.

JIRA: VSPERF-310

Change-Id: If8881cafb119f38f052403a1de497e9660187d2e
Signed-off-by: Christian Trautman <ctrautma@redhat.com>

1 files changed, 118 insertions, 0 deletions

diff --git a/tools/veth.py b/tools/veth.py
new file mode 100644
index 00000000..6418d11a
--- /dev/null
+++ b/tools/veth.py
@@ -0,0 +1,118 @@
+# Copyright 2016 Red Hat Corporation.
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#   http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+"""
+veth port emulation
+"""
+
+import logging
+import os
+
+from tools import tasks
+
+_LOGGER = logging.getLogger(__name__)
+
+
+def add_veth_port(port, peer_port):
+    """
+    Add a veth port
+    :param port:port name for the first port
+    :param peer_port: port name for the peer port
+    :return: None
+    """
+    # touch some files in a tmp area so we can track them. This allows us to
+    # track VSPerf created veth ports so they can be cleaned up if needed.
+    if not os.path.isdir('/tmp/veth'):
+        try:
+            os.mkdir('/tmp/veth')
+        except os.error:
+            # OK don't crash but cleanup may be an issue
+            _LOGGER.error('Unable to create veth temp folder.')
+            _LOGGER.error(
+                'Veth ports may not be removed on testcase completion')
+    if os.path.isdir('/tmp/veth'):
+        with open('/tmp/veth/{}-{}'.format(port, peer_port), 'a'):
+            os.utime('/tmp/veth/{}-{}'.format(port, peer_port), None)
+    tasks.run_task(['sudo', 'ip', 'link', 'add',
+                    port, 'type', 'veth', 'peer', 'name', peer_port],
+                   _LOGGER, 'Adding veth port {} with peer port {}...'.format(
+                       port, peer_port), False)
+
+
+def bring_up_eth_port(eth_port, namespace=None):
+    """
+    Bring up an eth port
+    :param eth_port: string of eth port to bring up
+    :param namespace: Namespace eth port it located if needed
+    :return: None
+    """
+    if namespace:
+        tasks.run_task(['sudo', 'ip', 'netns', 'exec', namespace,
+                        'ip', 'link', 'set', eth_port, 'up'],
+                       _LOGGER,
+                       'Bringing up port {} in namespace {}...'.format(
+                           eth_port, namespace), False)
+    else:
+        tasks.run_task(['sudo', 'ip', 'link', 'set', eth_port, 'up'],
+                       _LOGGER, 'Bringing up port...', False)
+
+
+def del_veth_port(port, peer_port):
+    """
+    Delete the veth ports, the peer will automatically be deleted on deletion
+    of the first port param
+    :param port: port name to delete
+    :param port: peer port name
+    :return: None
+    """
+    # delete the file if it exists in the temp area
+    if os.path.exists('/tmp/veth/{}-{}'.format(port, peer_port)):
+        os.remove('/tmp/veth/{}-{}'.format(port, peer_port))
+    tasks.run_task(['sudo', 'ip', 'link', 'del', port],
+                   _LOGGER, 'Deleting veth port {} with peer {}...'.format(
+                       port, peer_port), False)
+
+
+# pylint: disable=unused-argument
+def validate_add_veth_port(result, port, peer_port):
+    """
+    Validation function for integration testcases
+    """
+    devs = os.listdir('/sys/class/net')
+    return all([port in devs, peer_port in devs])
+
+
+def validate_bring_up_eth_port(result, eth_port, namespace=None):
+    """
+    Validation function for integration testcases
+    """
+    command = list()
+    if namespace:
+        command += ['ip', 'netns', 'exec', namespace]
+    command += ['cat', '/sys/class/net/{}/operstate'.format(eth_port)]
+    out = tasks.run_task(command, _LOGGER, 'Validating port up...', False)
+
+    # since different types of ports may report different status the best way
+    # we can do this for now is to just make sure it doesn't say down
+    if 'down' in out:
+        return False
+    return True
+
+
+def validate_del_veth_port(result, port, peer_port):
+    """
+    Validation function for integration testcases
+    """
+    devs = os.listdir('/sys/class/net')
+    return not any([port in devs, peer_port in devs])