[PATCH v3 19/20] avocado/tasst: Helpers to construct a simple network environment for tests

[David Gibson <david@gibson.dropbear.id.au>]

This constructs essentially the simplest sensible network for passt/pasta
to operate in.  We have one netns "simhost" to represent the host where we
will run passt or pasta, and a second "gw" to represent its default
gateway.

Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
---
 avocado/tasst/scenario/__init__.py | 11 ++++
 avocado/tasst/scenario/simple.py   | 98 ++++++++++++++++++++++++++++++
 2 files changed, 109 insertions(+)
 create mode 100644 avocado/tasst/scenario/__init__.py
 create mode 100644 avocado/tasst/scenario/simple.py

diff --git a/avocado/tasst/scenario/__init__.py b/avocado/tasst/scenario/__init__.py
new file mode 100644
index 0000000..8ca64a6
--- /dev/null
+++ b/avocado/tasst/scenario/__init__.py
@@ -0,0 +1,11 @@
+#! /usr/bin/python3
+
+# SPDX-License-Identifier: GPL-2.0-or-later
+#
+# tasst - Test A Simple Socket Transport
+#         library of test helpers for passt & pasta
+#
+# tasst/scenario - Helpers to set up various sample network topologies
+#
+# Copyright Red Hat
+# Author: David Gibson <david@gibson.dropbear.id.au>
diff --git a/avocado/tasst/scenario/simple.py b/avocado/tasst/scenario/simple.py
new file mode 100644
index 0000000..272d959
--- /dev/null
+++ b/avocado/tasst/scenario/simple.py
@@ -0,0 +1,98 @@
+#! /usr/bin/python3
+
+# SPDX-License-Identifier: GPL-2.0-or-later
+#
+# tasst - Test A Simple Socket Transport
+#         library of test helpers for passt & pasta
+#
+# tasst/scenario/simple - Smallest sensible network to use passt/pasta
+#
+# Copyright Red Hat
+# Author: David Gibson <david@gibson.dropbear.id.au>
+
+import contextlib
+
+from tasst import Tasst
+from tasst.nstool import UnshareSite
+from tasst.address import IpiAllocator, TEST_NET_2, TEST_NET6_TASST_B
+from tasst.site import Site
+from tasst.transfer import MetaTcpUploadTasst, MetaUdpTransferTasst, TransferTasstInfo
+from tasst.typing import typecheck
+
+
+class __SimpleNet:
+    """A simple network setup scenario
+
+    The sample network has 2 sites (network namespaces) connected with
+    a veth link:
+            [simhost]   <-veth->    [gw]
+
+    gw is set up as the default router for simhost.
+
+    simhost has addresses:
+        self.ip4 (IPv4), self.ip6 (IPv6), self.ip6_ll (IPv6 link local)
+
+    gw has addresses:
+        self.gw_ip4 (IPv4), self.gw_ip6 (IPv6), self.gw_ip6_ll (IPv6 link local)
+        self.remote_ip4 (IPv4), self.remote_ip6 (IPv6)
+
+    The "remote" addresses are on a different subnet from the others,
+    so the only way for simhost to reach them is via its default
+    route.  This helps to exercise that we're actually using that,
+    rather than just local net routes.
+
+    """
+
+    def __init__(self, hostsite, gwsite):
+        self.simhost = typecheck(hostsite, Site)
+        self.gw = typecheck(gwsite, Site)
+
+        self.ifname = 'veth'
+        self.gw_ifname = 'gw' + self.ifname
+        self.simhost.veth(self.ifname, self.gw_ifname, self.gw)
+
+        ipa_local = IpiAllocator()
+        self.ip4, self.ip6 = ipa_local.next_ipis()
+        self.gw_ip4, self.gw_ip6 = ipa_local.next_ipis()
+
+        ipa_remote = IpiAllocator(TEST_NET_2, TEST_NET6_TASST_B)
+        self.remote_ip4, self.remote_ip6 = ipa_remote.next_ipis()
+
+        self.gw.ifup('lo')
+        self.gw.ifup(self.gw_ifname, self.gw_ip4, self.gw_ip6,
+                     self.remote_ip4, self.remote_ip6)
+
+        self.simhost.ifup('lo')
+        self.simhost.ifup(self.ifname, self.ip4, self.ip6)
+
+        # Once link is up on both sides, SLAAC will run
+        self.gw_ip6_ll = self.gw.addr_wait(self.gw_ifname, family='inet6', scope='link')[0]
+        self.ip6_ll = self.simhost.addr_wait(self.ifname, family='inet6', scope='link')[0]
+
+        # Set up the default route
+        self.simhost.fg('ip -4 route add default via {}'.format(self.gw_ip4.ip), sudo=True)
+        self.simhost.fg('ip -6 route add default via {} dev {}'
+                        .format(self.gw_ip6_ll.ip, self.ifname), sudo=True)
+
+@contextlib.contextmanager
+def simple_net(name):
+    name = typecheck(name, str)
+    with UnshareSite(name + '.simhost', '-Ucnpf --mount-proc') as simhost, \
+         UnshareSite(name + '.gw', '-n', parent=simhost, sudo=True) as gw:
+        yield __SimpleNet(simhost, gw)
+
+
+class SimpleNetConnectivityTasst(MetaTcpUploadTasst, MetaUdpTransferTasst):
+    """
+    Check connectivity between the simulated host and the gateway,
+    before involving passt/pasta.
+
+    :avocado: tags=meta
+
+    """
+
+    @contextlib.contextmanager
+    def setup_transfer(self):
+        with simple_net(type(self).__name__) as simnet:
+            yield TransferTasstInfo('test/small.bin', simnet.simhost, simnet.gw,
+                                    simnet.remote_ip4.ip, simnet.remote_ip6.ip, 10000)
-- 
@@ -0,0 +1,98 @@
+#! /usr/bin/python3
+
+# SPDX-License-Identifier: GPL-2.0-or-later
+#
+# tasst - Test A Simple Socket Transport
+#         library of test helpers for passt & pasta
+#
+# tasst/scenario/simple - Smallest sensible network to use passt/pasta
+#
+# Copyright Red Hat
+# Author: David Gibson <david@gibson.dropbear.id.au>
+
+import contextlib
+
+from tasst import Tasst
+from tasst.nstool import UnshareSite
+from tasst.address import IpiAllocator, TEST_NET_2, TEST_NET6_TASST_B
+from tasst.site import Site
+from tasst.transfer import MetaTcpUploadTasst, MetaUdpTransferTasst, TransferTasstInfo
+from tasst.typing import typecheck
+
+
+class __SimpleNet:
+    """A simple network setup scenario
+
+    The sample network has 2 sites (network namespaces) connected with
+    a veth link:
+            [simhost]   <-veth->    [gw]
+
+    gw is set up as the default router for simhost.
+
+    simhost has addresses:
+        self.ip4 (IPv4), self.ip6 (IPv6), self.ip6_ll (IPv6 link local)
+
+    gw has addresses:
+        self.gw_ip4 (IPv4), self.gw_ip6 (IPv6), self.gw_ip6_ll (IPv6 link local)
+        self.remote_ip4 (IPv4), self.remote_ip6 (IPv6)
+
+    The "remote" addresses are on a different subnet from the others,
+    so the only way for simhost to reach them is via its default
+    route.  This helps to exercise that we're actually using that,
+    rather than just local net routes.
+
+    """
+
+    def __init__(self, hostsite, gwsite):
+        self.simhost = typecheck(hostsite, Site)
+        self.gw = typecheck(gwsite, Site)
+
+        self.ifname = 'veth'
+        self.gw_ifname = 'gw' + self.ifname
+        self.simhost.veth(self.ifname, self.gw_ifname, self.gw)
+
+        ipa_local = IpiAllocator()
+        self.ip4, self.ip6 = ipa_local.next_ipis()
+        self.gw_ip4, self.gw_ip6 = ipa_local.next_ipis()
+
+        ipa_remote = IpiAllocator(TEST_NET_2, TEST_NET6_TASST_B)
+        self.remote_ip4, self.remote_ip6 = ipa_remote.next_ipis()
+
+        self.gw.ifup('lo')
+        self.gw.ifup(self.gw_ifname, self.gw_ip4, self.gw_ip6,
+                     self.remote_ip4, self.remote_ip6)
+
+        self.simhost.ifup('lo')
+        self.simhost.ifup(self.ifname, self.ip4, self.ip6)
+
+        # Once link is up on both sides, SLAAC will run
+        self.gw_ip6_ll = self.gw.addr_wait(self.gw_ifname, family='inet6', scope='link')[0]
+        self.ip6_ll = self.simhost.addr_wait(self.ifname, family='inet6', scope='link')[0]
+
+        # Set up the default route
+        self.simhost.fg('ip -4 route add default via {}'.format(self.gw_ip4.ip), sudo=True)
+        self.simhost.fg('ip -6 route add default via {} dev {}'
+                        .format(self.gw_ip6_ll.ip, self.ifname), sudo=True)
+
+@contextlib.contextmanager
+def simple_net(name):
+    name = typecheck(name, str)
+    with UnshareSite(name + '.simhost', '-Ucnpf --mount-proc') as simhost, \
+         UnshareSite(name + '.gw', '-n', parent=simhost, sudo=True) as gw:
+        yield __SimpleNet(simhost, gw)
+
+
+class SimpleNetConnectivityTasst(MetaTcpUploadTasst, MetaUdpTransferTasst):
+    """
+    Check connectivity between the simulated host and the gateway,
+    before involving passt/pasta.
+
+    :avocado: tags=meta
+
+    """
+
+    @contextlib.contextmanager
+    def setup_transfer(self):
+        with simple_net(type(self).__name__) as simnet:
+            yield TransferTasstInfo('test/small.bin', simnet.simhost, simnet.gw,
+                                    simnet.remote_ip4.ip, simnet.remote_ip6.ip, 10000)
-- 
2.40.1