SCTP stack (RFC4960)

== CONTENT ==
* SCTP chunks definition as per RFC4960;
* Helper functions to set/get values to/from the corresponding chunks;
* Hooks to the session/application layers;
* Complete state-machine handling;
* Implementation for unexpected chunk received in a certain
state (state-machine error handling)
* Support for 1-single connection;
* Sample application to test receive/transmit data-path;
* Test to validate SCTP stack;

Change-Id: I1b55c455ab400be9513f4e094dadfc3181d2ebc9
Signed-off-by: Marco Varlese <marco.varlese@suse.com>

test/test_sctp.py

@@ -0,0 +1,91 @@
+#!/usr/bin/env python
+
+import unittest
+
+from framework import VppTestCase, VppTestRunner
+from vpp_ip_route import VppIpTable, VppIpRoute, VppRoutePath
+
+
+class TestSCTP(VppTestCase):
+    """ SCTP Test Case """
+
+    @classmethod
+    def setUpClass(cls):
+        super(TestSCTP, cls).setUpClass()
+
+    def setUp(self):
+        super(TestSCTP, self).setUp()
+        self.vapi.session_enable_disable(is_enabled=1)
+        self.create_loopback_interfaces(range(2))
+
+        table_id = 0
+
+        for i in self.lo_interfaces:
+            i.admin_up()
+
+            if table_id != 0:
+                tbl = VppIpTable(self, table_id)
+                tbl.add_vpp_config()
+
+            i.set_table_ip4(table_id)
+            i.config_ip4()
+            table_id += 1
+
+        # Configure namespaces
+        self.vapi.app_namespace_add(namespace_id="0",
+                                    sw_if_index=self.loop0.sw_if_index)
+        self.vapi.app_namespace_add(namespace_id="1",
+                                    sw_if_index=self.loop1.sw_if_index)
+
+    def tearDown(self):
+        for i in self.lo_interfaces:
+            i.unconfig_ip4()
+            i.set_table_ip4(0)
+            i.admin_down()
+        self.vapi.session_enable_disable(is_enabled=0)
+        super(TestSCTP, self).tearDown()
+
+    def test_sctp_unittest(self):
+        """ SCTP Unit Tests """
+        error = self.vapi.cli("test sctp all")
+
+        if error:
+            self.logger.critical(error)
+        self.assertEqual(error.find("failed"), -1)
+
+    def test_sctp_transfer(self):
+        """ SCTP builtin client/server transfer """
+
+        # Add inter-table routes
+        ip_t01 = VppIpRoute(self, self.loop1.local_ip4, 32,
+                            [VppRoutePath("0.0.0.0",
+                                          0xffffffff,
+                                          nh_table_id=1)])
+        ip_t10 = VppIpRoute(self, self.loop0.local_ip4, 32,
+                            [VppRoutePath("0.0.0.0",
+                                          0xffffffff,
+                                          nh_table_id=0)], table_id=1)
+        ip_t01.add_vpp_config()
+        ip_t10.add_vpp_config()
+
+        # Start builtin server and client
+        uri = "sctp://" + self.loop0.local_ip4 + "/1234"
+        error = self.vapi.cli("test sctp server appns 0 fifo-size 4 uri " +
+                              uri)
+        if error:
+            self.logger.critical(error)
+
+        error = self.vapi.cli("test sctp client mbytes 10 appns 1" +
+                              " fifo-size 4" +
+                              " no-output test-bytes syn-timeout 20 " +
+                              " uri " + uri)
+        if error:
+            self.logger.critical(error)
+        self.assertEqual(error.find("failed"), -1)
+
+        # Delete inter-table routes
+        ip_t01.remove_vpp_config()
+        ip_t10.remove_vpp_config()
+
+if __name__ == '__main__':
+    unittest.main(testRunner=VppTestRunner)