GBP plugin

Group Base Policy (GBP) defines:
 - endpoints: typically a VM or container that is connected to the
              virtual switch/router (i.e. to VPP)
 - endpoint-group: (EPG) a collection of endpoints
 - policy: rules determining which traffic can pass between EPGs a.k.a
            a 'contract'

Here, policy is implemented via an ACL.
EPG classification for transit packets is determined by:
 - source EPG: from the packet's input interface
 - destination EPG: from the packet's destination IP address.

Change-Id: I7b983844826b5fc3d49e21353ebda9df9b224e25
Signed-off-by: Neale Ranns <neale.ranns@cisco.com>
diff --git a/src/vpp-api/vom/gbp_contract.cpp b/src/vpp-api/vom/gbp_contract.cpp
new file mode 100644
index 0000000..d648fb3
--- /dev/null
+++ b/src/vpp-api/vom/gbp_contract.cpp
@@ -0,0 +1,193 @@
+/*
+ * Copyright (c) 2017 Cisco and/or its affiliates.
+ * 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.
+ */
+
+#include "vom/gbp_contract.hpp"
+#include "vom/gbp_contract_cmds.hpp"
+
+namespace VOM {
+
+singular_db<gbp_contract::key_t, gbp_contract> gbp_contract::m_db;
+
+gbp_contract::event_handler gbp_contract::m_evh;
+
+gbp_contract::gbp_contract(epg_id_t src_epg_id,
+                           epg_id_t dst_epg_id,
+                           const ACL::l3_list& acl)
+  : m_hw(false)
+  , m_src_epg_id(src_epg_id)
+  , m_dst_epg_id(dst_epg_id)
+  , m_acl(acl.singular())
+{
+}
+
+gbp_contract::gbp_contract(const gbp_contract& gbpc)
+  : m_hw(gbpc.m_hw)
+  , m_src_epg_id(gbpc.m_src_epg_id)
+  , m_dst_epg_id(gbpc.m_dst_epg_id)
+  , m_acl(gbpc.m_acl)
+{
+}
+
+gbp_contract::~gbp_contract()
+{
+  sweep();
+
+  // not in the DB anymore.
+  m_db.release(key(), this);
+}
+
+const gbp_contract::key_t
+gbp_contract::key() const
+{
+  return (std::make_pair(m_src_epg_id, m_dst_epg_id));
+}
+
+bool
+gbp_contract::operator==(const gbp_contract& gbpc) const
+{
+  return ((key() == gbpc.key()) && (m_acl->handle() == gbpc.m_acl->handle()));
+}
+
+void
+gbp_contract::sweep()
+{
+  if (m_hw) {
+    HW::enqueue(
+      new gbp_contract_cmds::delete_cmd(m_hw, m_src_epg_id, m_dst_epg_id));
+  }
+  HW::write();
+}
+
+void
+gbp_contract::replay()
+{
+  if (m_hw) {
+    HW::enqueue(new gbp_contract_cmds::create_cmd(
+      m_hw, m_src_epg_id, m_dst_epg_id, m_acl->handle()));
+  }
+}
+
+std::string
+gbp_contract::to_string() const
+{
+  std::ostringstream s;
+  s << "gbp-contract:[{" << m_src_epg_id << ", " << m_dst_epg_id << "}, "
+    << m_acl->to_string() << "]";
+
+  return (s.str());
+}
+
+void
+gbp_contract::update(const gbp_contract& r)
+{
+  /*
+ * create the table if it is not yet created
+ */
+  if (rc_t::OK != m_hw.rc()) {
+    HW::enqueue(new gbp_contract_cmds::create_cmd(
+      m_hw, m_src_epg_id, m_dst_epg_id, m_acl->handle()));
+  }
+}
+
+std::shared_ptr<gbp_contract>
+gbp_contract::find_or_add(const gbp_contract& temp)
+{
+  return (m_db.find_or_add(temp.key(), temp));
+}
+
+std::shared_ptr<gbp_contract>
+gbp_contract::find(const key_t& k)
+{
+  return (m_db.find(k));
+}
+
+std::shared_ptr<gbp_contract>
+gbp_contract::singular() const
+{
+  return find_or_add(*this);
+}
+
+void
+gbp_contract::dump(std::ostream& os)
+{
+  m_db.dump(os);
+}
+
+gbp_contract::event_handler::event_handler()
+{
+  OM::register_listener(this);
+  inspect::register_handler({ "gbp-contract" }, "GBP Contract", this);
+}
+
+void
+gbp_contract::event_handler::handle_replay()
+{
+  m_db.replay();
+}
+
+void
+gbp_contract::event_handler::handle_populate(const client_db::key_t& key)
+{
+  std::shared_ptr<gbp_contract_cmds::dump_cmd> cmd =
+    std::make_shared<gbp_contract_cmds::dump_cmd>();
+
+  HW::enqueue(cmd);
+  HW::write();
+
+  for (auto& record : *cmd) {
+    auto& payload = record.get_payload();
+
+    std::shared_ptr<ACL::l3_list> acl =
+      ACL::l3_list::find(payload.contract.acl_index);
+
+    if (acl) {
+      gbp_contract gbpc(payload.contract.src_epg, payload.contract.dst_epg,
+                        *acl);
+      OM::commit(key, gbpc);
+
+      VOM_LOG(log_level_t::DEBUG) << "read: " << gbpc.to_string();
+    }
+  }
+}
+
+dependency_t
+gbp_contract::event_handler::order() const
+{
+  return (dependency_t::ENTRY);
+}
+
+void
+gbp_contract::event_handler::show(std::ostream& os)
+{
+  m_db.dump(os);
+}
+
+std::ostream&
+operator<<(std::ostream& os, const gbp_contract::key_t& key)
+{
+  os << "{ " << key.first << "," << key.second << "}";
+
+  return (os);
+}
+
+} // namespace VOM
+
+/*
+ * fd.io coding-style-patch-verification: ON
+ *
+ * Local Variables:
+ * eval: (c-set-style "mozilla")
+ * End:
+ */