DHCP Client Dump

- use types on the DHCP API so that the same data is sent in comfing messages and in dumps
- add the DHCP client dump API
- update VOM to refelct API changes
- rename VOM class dhcp_config* dhcp_client*
- the VOM dhcp_client class maintains the lease data (which it reads on a dump) for clients to read

Change-Id: I2a43463937cbd80c01d45798e74b21288d8b8ead
Signed-off-by: Neale Ranns <neale.ranns@cisco.com>

9 files changed, 610 insertions, 318 deletions

diff --git a/extras/vom/vom/Makefile.am b/extras/vom/vom/Makefile.am
index 892f437976e..2abf3463c8f 100644
--- a/extras/vom/vom/Makefile.am
+++ b/extras/vom/vom/Makefile.am
@@ -98,8 +98,8 @@ libvom_la_SOURCES = 			\
 	client_db.cpp			\
 	cmd.cpp				\
 	connection.cpp			\
-	dhcp_config_cmds.cpp		\
-	dhcp_config.cpp			\
+	dhcp_client_cmds.cpp		\
+	dhcp_client.cpp			\
 	hw_cmds.cpp			\
 	hw.cpp				\
 	inspect.cpp			\
@@ -192,8 +192,7 @@ vominclude_HEADERS =			\
 	client_db.hpp			\
 	cmd.hpp				\
 	connection.hpp			\
-	dhcp_config.hpp			\
-	dhcp_config_cmds.hpp		\
+	dhcp_client.hpp			\
 	dump_cmd.hpp			\
 	enum_base.hpp			\
 	event_cmd.hpp			\
diff --git a/extras/vom/vom/dhcp_client.cpp b/extras/vom/vom/dhcp_client.cpp
new file mode 100644
index 00000000000..fcadfa69ded
--- /dev/null
+++ b/extras/vom/vom/dhcp_client.cpp
@@ -0,0 +1,346 @@
+/*
+ * 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/dhcp_client.hpp"
+#include "vom/dhcp_client_cmds.hpp"
+#include "vom/singular_db_funcs.hpp"
+
+namespace VOM {
+const dhcp_client::state_t dhcp_client::state_t::DISCOVER(0, "discover");
+const dhcp_client::state_t dhcp_client::state_t::REQUEST(1, "request");
+const dhcp_client::state_t dhcp_client::state_t::BOUND(2, "bound");
+
+dhcp_client::state_t::state_t(int v, const std::string& s)
+  : enum_base<dhcp_client::state_t>(v, s)
+{
+}
+
+const dhcp_client::state_t&
+dhcp_client::state_t::from_vpp(int n)
+{
+  if (REQUEST == n)
+    return (REQUEST);
+  if (BOUND == n)
+    return (BOUND);
+
+  return (DISCOVER);
+}
+
+singular_db<interface::key_t, dhcp_client> dhcp_client::m_db;
+std::weak_ptr<dhcp_client_cmds::events_cmd> dhcp_client::m_s_event_cmd;
+dhcp_client::dhcp_client_listener dhcp_client::m_listener;
+
+dhcp_client::event_handler dhcp_client::m_evh;
+
+dhcp_client::dhcp_client(const interface& itf,
+                         const std::string& hostname,
+                         bool set_broadcast_flag,
+                         event_listener* ev)
+  : m_itf(itf.singular())
+  , m_hostname(hostname)
+  , m_client_id(l2_address_t::ZERO)
+  , m_set_broadcast_flag(set_broadcast_flag)
+  , m_binding(0)
+  , m_evl(ev)
+  , m_event_cmd(get_event_cmd())
+{
+}
+
+dhcp_client::dhcp_client(const interface& itf,
+                         const std::string& hostname,
+                         const l2_address_t& client_id,
+                         bool set_broadcast_flag,
+                         event_listener* ev)
+  : m_itf(itf.singular())
+  , m_hostname(hostname)
+  , m_client_id(client_id)
+  , m_set_broadcast_flag(set_broadcast_flag)
+  , m_binding(0)
+  , m_evl(ev)
+  , m_event_cmd(get_event_cmd())
+{
+}
+
+dhcp_client::dhcp_client(const dhcp_client& o)
+  : m_itf(o.m_itf)
+  , m_hostname(o.m_hostname)
+  , m_client_id(o.m_client_id)
+  , m_set_broadcast_flag(o.m_set_broadcast_flag)
+  , m_binding(0)
+  , m_evl(o.m_evl)
+  , m_event_cmd(o.m_event_cmd)
+{
+}
+
+dhcp_client::~dhcp_client()
+{
+  sweep();
+
+  // not in the DB anymore.
+  m_db.release(m_itf->key(), this);
+}
+
+bool
+dhcp_client::operator==(const dhcp_client& l) const
+{
+  return ((key() == l.key()) && (m_hostname == l.m_hostname) &&
+          (m_client_id == l.m_client_id));
+}
+
+const dhcp_client::key_t&
+dhcp_client::key() const
+{
+  return (m_itf->key());
+}
+
+void
+dhcp_client::sweep()
+{
+  if (m_binding) {
+    HW::enqueue(
+      new dhcp_client_cmds::unbind_cmd(m_binding, m_itf->handle(), m_hostname));
+  }
+  HW::write();
+}
+
+void
+dhcp_client::dump(std::ostream& os)
+{
+  db_dump(m_db, os);
+}
+
+void
+dhcp_client::replay()
+{
+  if (m_binding) {
+    HW::enqueue(new dhcp_client_cmds::bind_cmd(m_binding, m_itf->handle(),
+                                               m_hostname, m_client_id));
+  }
+}
+
+std::string
+dhcp_client::to_string() const
+{
+  std::ostringstream s;
+  s << "DHCP-client: " << m_itf->to_string() << " hostname:" << m_hostname
+    << " client_id:[" << m_client_id << "] " << m_binding.to_string();
+  if (m_lease)
+    s << " " << m_lease->to_string();
+  else
+    s << " no-lease";
+
+  return (s.str());
+}
+
+void
+dhcp_client::update(const dhcp_client& desired)
+{
+  /*
+   * the desired state is always that the interface should be created
+   */
+  if (!m_binding) {
+    HW::enqueue(new dhcp_client_cmds::bind_cmd(m_binding, m_itf->handle(),
+                                               m_hostname, m_client_id));
+  }
+
+  if (desired.m_lease)
+    m_lease = desired.m_lease;
+  if (m_evl != desired.m_evl) {
+    m_evl = desired.m_evl;
+  }
+}
+
+const std::shared_ptr<dhcp_client::lease_t>
+dhcp_client::lease() const
+{
+  return (m_lease);
+}
+
+void
+dhcp_client::lease(std::shared_ptr<dhcp_client::lease_t> lease)
+{
+  m_lease = lease;
+}
+
+std::shared_ptr<dhcp_client>
+dhcp_client::find_or_add(const dhcp_client& temp)
+{
+  return (m_db.find_or_add(temp.m_itf->key(), temp));
+}
+
+std::shared_ptr<dhcp_client>
+dhcp_client::find(const key_t& k)
+{
+  return (m_db.find(k));
+}
+
+std::shared_ptr<dhcp_client>
+dhcp_client::singular() const
+{
+  return find_or_add(*this);
+}
+
+dhcp_client::lease_t::lease_t()
+  : state(state_t::DISCOVER)
+  , mac(mac_address_t::ZERO)
+{
+}
+
+dhcp_client::lease_t::lease_t(const state_t& state,
+                              std::shared_ptr<interface> itf,
+                              const boost::asio::ip::address& router_address,
+                              const route::prefix_t& host_prefix,
+                              const std::string& hostname,
+                              const mac_address_t& mac)
+  : state(state)
+  , itf(itf)
+  , router_address(router_address)
+  , host_prefix(host_prefix)
+  , hostname(hostname)
+  , mac(mac)
+{
+}
+
+std::string
+dhcp_client::lease_t::to_string() const
+{
+  std::stringstream ss;
+
+  ss << "lease:[" << itf->to_string() << " state: " << state.to_string()
+     << " host: " << host_prefix.to_string() << " router: " << router_address
+     << " mac: " << mac.to_string() << "]";
+
+  return (ss.str());
+}
+
+dhcp_client::event_listener::event_listener()
+  : m_status(rc_t::NOOP)
+{
+}
+
+HW::item<bool>&
+dhcp_client::event_listener::status()
+{
+  return (m_status);
+}
+
+dhcp_client::event_handler::event_handler()
+{
+  OM::register_listener(this);
+  inspect::register_handler({ "dhcp" }, "DHCP clients", this);
+}
+
+void
+dhcp_client::event_handler::handle_replay()
+{
+  m_db.replay();
+}
+
+void
+dhcp_client::event_handler::handle_populate(const client_db::key_t& key)
+{
+  std::shared_ptr<dhcp_client_cmds::dump_cmd> cmd =
+    std::make_shared<dhcp_client_cmds::dump_cmd>();
+
+  HW::enqueue(cmd);
+  HW::write();
+
+  for (auto& record : *cmd) {
+    auto& payload = record.get_payload();
+
+    std::shared_ptr<interface> itf =
+      interface::find(payload.client.sw_if_index);
+
+    if (!itf) {
+      VOM_LOG(log_level_t::ERROR) << "dhcp-client dump:"
+                                  << " itf:" << payload.client.sw_if_index;
+      continue;
+    }
+
+    const dhcp_client::state_t& s =
+      dhcp_client::state_t::from_vpp(payload.lease.state);
+    route::prefix_t pfx(payload.lease.is_ipv6, payload.lease.host_address,
+                        payload.lease.mask_width);
+    std::string hostname =
+      reinterpret_cast<const char*>(payload.lease.hostname);
+    l2_address_t l2(payload.client.id + 1);
+    dhcp_client dc(*itf, hostname, l2, payload.client.set_broadcast_flag);
+    dc.lease(std::make_shared<dhcp_client::lease_t>(
+      s, itf, from_bytes(0, payload.lease.router_address), pfx, hostname,
+      mac_address_t(payload.lease.host_mac)));
+    OM::commit(key, dc);
+  }
+}
+
+dependency_t
+dhcp_client::event_handler::order() const
+{
+  return (dependency_t::BINDING);
+}
+
+void
+dhcp_client::event_handler::show(std::ostream& os)
+{
+  db_dump(m_db, os);
+}
+
+std::shared_ptr<dhcp_client_cmds::events_cmd>
+dhcp_client::get_event_cmd()
+{
+  if (m_s_event_cmd.expired()) {
+    std::shared_ptr<dhcp_client_cmds::events_cmd> c =
+      std::make_shared<dhcp_client_cmds::events_cmd>(m_listener);
+
+    m_s_event_cmd = c;
+
+    HW::enqueue(c);
+    HW::write();
+
+    return c;
+  }
+
+  return (m_s_event_cmd.lock());
+}
+
+void
+dhcp_client::handle_dhcp_event(std::shared_ptr<lease_t> lease)
+{
+  m_lease = lease;
+  if (m_evl)
+    m_evl->handle_dhcp_event(m_lease);
+}
+
+void
+dhcp_client::dhcp_client_listener::handle_dhcp_event(std::shared_ptr<lease_t> e)
+{
+  /*
+   * Find the client the event references
+   */
+  std::shared_ptr<dhcp_client> client = find(e->itf->key());
+
+  if (client) {
+    client->handle_dhcp_event(e);
+  }
+}
+
+}; // namespace VOM
+
+/*
+ * fd.io coding-style-patch-verification: ON
+ *
+ * Local Variables:
+ * eval: (c-set-style "mozilla")
+ * End:
+ */
diff --git a/extras/vom/vom/dhcp_config.hpp b/extras/vom/vom/dhcp_client.hpp
index 8ea608d809d..17c626ed0f1 100644
--- a/extras/vom/vom/dhcp_config.hpp
+++ b/extras/vom/vom/dhcp_client.hpp
@@ -13,60 +13,130 @@
  * limitations under the License.
  */
 
-#ifndef __VOM_DHCP_CONFIG_H__
-#define __VOM_DHCP_CONFIG_H__
+#ifndef __VOM_DHCP_CLIENT_H__
+#define __VOM_DHCP_CLIENT_H__
 
 #include "vom/hw.hpp"
 #include "vom/inspect.hpp"
 #include "vom/interface.hpp"
 #include "vom/object_base.hpp"
 #include "vom/om.hpp"
+#include "vom/prefix.hpp"
 #include "vom/singular_db.hpp"
 
 namespace VOM {
-namespace dhcp_config_cmds {
+namespace dhcp_client_cmds {
 class events_cmd;
 };
 /**
- * A representation of DHCP client configuration on an interface
+ * A representation of DHCP client on an interface
  */
-class dhcp_config : public object_base
+class dhcp_client : public object_base
 {
 public:
   /**
-   * typedef for the DHCP config key type
+   * typedef for the DHCP client key type
    */
   typedef interface::key_t key_t;
 
+  struct state_t : enum_base<state_t>
+  {
+    const static state_t DISCOVER;
+    const static state_t REQUEST;
+    const static state_t BOUND;
+
+    static const state_t& from_vpp(int i);
+
+  private:
+    /**
+     * Private constructor taking the value and the string name
+     */
+    state_t(int v, const std::string& s);
+  };
+
+  /**
+   * A DHCP lease data
+   */
+  struct lease_t
+  {
+    lease_t();
+    lease_t(const state_t& state,
+            std::shared_ptr<interface> itf,
+            const boost::asio::ip::address& router_address,
+            const route::prefix_t& host_prefix,
+            const std::string& hostname,
+            const mac_address_t& mac);
+
+    std::string to_string() const;
+
+    const state_t& state;
+    std::shared_ptr<interface> itf;
+    boost::asio::ip::address router_address;
+    route::prefix_t host_prefix;
+    std::string hostname;
+    mac_address_t mac;
+  };
+
+  /**
+   * A class that listens to DHCP Events
+   */
+  class event_listener
+  {
+  public:
+    /**
+     * Constructor
+     */
+    event_listener();
+
+    /**
+     * listener's virtual function invoked when a DHCP event is
+     * available to read
+     */
+    virtual void handle_dhcp_event(std::shared_ptr<lease_t> e) = 0;
+
+    /**
+     * Return the HW::item associated with this command
+     */
+    HW::item<bool>& status();
+
+  protected:
+    /**
+     * The HW::item associated with this command
+     */
+    HW::item<bool> m_status;
+  };
+
   /**
    * Construct a new object matching the desried state
    */
-  dhcp_config(const interface& itf,
+  dhcp_client(const interface& itf,
               const std::string& hostname,
-              bool set_broadcast_flag = true);
+              bool set_broadcast_flag = true,
+              event_listener* ev = nullptr);
 
   /**
    * Construct a new object matching the desried state
    */
-  dhcp_config(const interface& itf,
+  dhcp_client(const interface& itf,
               const std::string& hostname,
               const l2_address_t& client_id,
-              bool set_broadcast_flag = true);
+              bool set_broadcast_flag = true,
+              event_listener* ev = nullptr);
 
   /**
    * Copy Constructor
    */
-  dhcp_config(const dhcp_config& o);
+  dhcp_client(const dhcp_client& o);
 
   /**
    * Destructor
    */
-  ~dhcp_config();
+  ~dhcp_client();
 
   /**
    * Comparison operator - for UT
    */
-  bool operator==(const dhcp_config& d) const;
+  bool operator==(const dhcp_client& d) const;
 
   /**
    * Return the object's key
@@ -74,9 +144,9 @@ public:
   const key_t& key() const;
 
   /**
-   * Return the 'singular' of the DHCP config that matches this object
+   * Return the 'singular' of the DHCP client that matches this object
    */
-  std::shared_ptr<dhcp_config> singular() const;
+  std::shared_ptr<dhcp_client> singular() const;
 
   /**
    * convert to string format for debug purposes
@@ -84,43 +154,19 @@ public:
   std::string to_string() const;
 
   /**
-   * Dump all DHCP configs into the stream provided
+   * Dump all DHCP clients into the stream provided
    */
   static void dump(std::ostream& os);
 
   /**
-   * Find a DHCP config from its key
+   * Find a DHCP client from its key
    */
-  static std::shared_ptr<dhcp_config> find(const key_t& k);
+  static std::shared_ptr<dhcp_client> find(const key_t& k);
 
   /**
- * A class that listens to DHCP Events
- */
-  class event_listener
-  {
-  public:
-    /**
-     * Constructor
-     */
-    event_listener();
-
-    /**
-     * listener's virtual function invoked when a DHCP event is
-     * available to read
-     */
-    virtual void handle_dhcp_event(dhcp_config_cmds::events_cmd* cmd) = 0;
-
-    /**
-     * Return the HW::item associated with this command
-     */
-    HW::item<bool>& status();
-
-  protected:
-    /**
-     * The HW::item associated with this command
-     */
-    HW::item<bool> m_status;
-  };
+   * return the current lease data
+   */
+  const std::shared_ptr<lease_t> lease() const;
 
 private:
   /**
@@ -161,12 +207,12 @@ private:
   /**
    * Enquue commonds to the VPP command Q for the update
    */
-  void update(const dhcp_config& obj);
+  void update(const dhcp_client& obj);
 
   /**
-   * Find or add DHCP config to the OM
+   * Find or add DHCP client to the OM
    */
-  static std::shared_ptr<dhcp_config> find_or_add(const dhcp_config& temp);
+  static std::shared_ptr<dhcp_client> find_or_add(const dhcp_client& temp);
 
   /*
    * It's the OM class that calls singular()
@@ -176,7 +222,7 @@ private:
   /**
    * It's the singular_db class that calls replay()
    */
-  friend class singular_db<key_t, dhcp_config>;
+  friend class singular_db<key_t, dhcp_client>;
 
   /**
    * Sweep/reap the object if still stale
@@ -188,20 +234,22 @@ private:
    */
   void replay(void);
 
+  void lease(std::shared_ptr<lease_t> l);
+
   /**
-   * A reference counting pointer to the interface on which DHCP config
+   * A reference counting pointer to the interface on which DHCP client
    * resides. By holding the reference here, we can guarantee that
    * this object will outlive the interface
    */
   const std::shared_ptr<interface> m_itf;
 
   /**
-   * The hostname in the DHCP configuration
+   * The hostname in the DHCP client
    */
   const std::string m_hostname;
 
   /**
-   * The option-61 client_id in the DHCP configuration
+   * The option-61 client_id in the DHCP client
    */
   const l2_address_t m_client_id;
 
@@ -213,13 +261,41 @@ private:
   /**
    * HW configuration for the binding. The bool representing the
    * do/don't bind.
- */
+   */
   HW::item<bool> m_binding;
 
   /**
-   * A map of all Dhcp configs keyed against the interface.
+   * A pointer to an event listener for client events
    */
-  static singular_db<key_t, dhcp_config> m_db;
+  event_listener* m_evl;
+
+  /**
+   * Current lease state for this client
+   */
+  std::shared_ptr<lease_t> m_lease;
+
+  std::shared_ptr<dhcp_client_cmds::events_cmd> m_event_cmd;
+
+  void handle_dhcp_event(std::shared_ptr<lease_t> e);
+
+  /**
+   * A map of all Dhcp clients keyed against the interface.
+   */
+  static singular_db<key_t, dhcp_client> m_db;
+
+  static std::weak_ptr<dhcp_client_cmds::events_cmd> m_s_event_cmd;
+  static std::shared_ptr<dhcp_client_cmds::events_cmd> get_event_cmd();
+
+  class dhcp_client_listener : public event_listener
+  {
+  public:
+    /**
+     * listener's virtual function invoked when a DHCP event is
+     * available to read
+     */
+    void handle_dhcp_event(std::shared_ptr<lease_t> e);
+  };
+  static dhcp_client_listener m_listener;
 };
 };
 
diff --git a/extras/vom/vom/dhcp_config_cmds.cpp b/extras/vom/vom/dhcp_client_cmds.cpp
index 76ce58b6b92..181a15f8f96 100644
--- a/extras/vom/vom/dhcp_config_cmds.cpp
+++ b/extras/vom/vom/dhcp_client_cmds.cpp
@@ -13,12 +13,12 @@
  * limitations under the License.
  */
 
-#include "vom/dhcp_config_cmds.hpp"
+#include "vom/dhcp_client_cmds.hpp"
 
 DEFINE_VAPI_MSG_IDS_DHCP_API_JSON;
 
 namespace VOM {
-namespace dhcp_config_cmds {
+namespace dhcp_client_cmds {
 
 bind_cmd::bind_cmd(HW::item<bool>& item,
                    const handle_t& itf,
@@ -45,21 +45,21 @@ bind_cmd::issue(connection& con)
   msg_t req(con.ctx(), std::ref(*this));
 
   auto& payload = req.get_request().get_payload();
-  payload.sw_if_index = m_itf.value();
   payload.is_add = 1;
-  payload.pid = getpid();
-  payload.want_dhcp_event = 1;
-  payload.set_broadcast_flag = m_set_broadcast_flag;
+  payload.client.sw_if_index = m_itf.value();
+  payload.client.pid = getpid();
+  payload.client.want_dhcp_event = 1;
+  payload.client.set_broadcast_flag = m_set_broadcast_flag;
 
-  memset(payload.hostname, 0, sizeof(payload.hostname));
-  memcpy(payload.hostname, m_hostname.c_str(),
-         std::min(sizeof(payload.hostname), m_hostname.length()));
+  memset(payload.client.hostname, 0, sizeof(payload.client.hostname));
+  memcpy(payload.client.hostname, m_hostname.c_str(),
+         std::min(sizeof(payload.client.hostname), m_hostname.length()));
 
-  memset(payload.client_id, 0, sizeof(payload.client_id));
-  payload.client_id[0] = 1;
+  memset(payload.client.id, 0, sizeof(payload.client.id));
+  payload.client.id[0] = 1;
   std::copy_n(begin(m_client_id.bytes),
-              std::min(sizeof(payload.client_id), m_client_id.bytes.size()),
-              payload.client_id + 1);
+              std::min(sizeof(payload.client.id), m_client_id.bytes.size()),
+              payload.client.id + 1);
 
   VAPI_CALL(req.execute());
 
@@ -72,7 +72,7 @@ std::string
 bind_cmd::to_string() const
 {
   std::ostringstream s;
-  s << "Dhcp-config-bind: " << m_hw_item.to_string()
+  s << "Dhcp-client-bind: " << m_hw_item.to_string()
     << " itf:" << m_itf.to_string() << " hostname:" << m_hostname;
 
   return (s.str());
@@ -99,13 +99,13 @@ unbind_cmd::issue(connection& con)
   msg_t req(con.ctx(), std::ref(*this));
 
   auto& payload = req.get_request().get_payload();
-  payload.sw_if_index = m_itf.value();
   payload.is_add = 0;
-  payload.pid = getpid();
-  payload.want_dhcp_event = 0;
+  payload.client.sw_if_index = m_itf.value();
+  payload.client.pid = getpid();
+  payload.client.want_dhcp_event = 0;
 
-  memcpy(payload.hostname, m_hostname.c_str(),
-         std::min(sizeof(payload.hostname), m_hostname.length()));
+  memcpy(payload.client.hostname, m_hostname.c_str(),
+         std::min(sizeof(payload.client.hostname), m_hostname.length()));
 
   VAPI_CALL(req.execute());
 
@@ -119,18 +119,23 @@ std::string
 unbind_cmd::to_string() const
 {
   std::ostringstream s;
-  s << "Dhcp-config-unbind: " << m_hw_item.to_string()
+  s << "Dhcp-client-unbind: " << m_hw_item.to_string()
     << " itf:" << m_itf.to_string() << " hostname:" << m_hostname;
 
   return (s.str());
 }
 
-events_cmd::events_cmd(dhcp_config::event_listener& el)
+events_cmd::events_cmd(dhcp_client::event_listener& el)
   : event_cmd(el.status())
   , m_listener(el)
 {
 }
 
+events_cmd::~events_cmd()
+{
+  VOM_LOG(log_level_t::INFO) << "DHCP events destroyed";
+}
+
 bool
 events_cmd::operator==(const events_cmd& other) const
 {
@@ -159,7 +164,31 @@ events_cmd::retire(connection& con)
 void
 events_cmd::notify()
 {
-  m_listener.handle_dhcp_event(this);
+  for (auto& msg : *this) {
+    auto& payload = msg.get_payload();
+
+    const dhcp_client::state_t& s =
+      dhcp_client::state_t::from_vpp(payload.lease.state);
+    route::prefix_t pfx(payload.lease.is_ipv6, payload.lease.host_address,
+                        payload.lease.mask_width);
+    std::shared_ptr<interface> itf = interface::find(payload.lease.sw_if_index);
+
+    if (itf) {
+      std::shared_ptr<dhcp_client::lease_t> ev =
+        std::make_shared<dhcp_client::lease_t>(
+          s, itf, from_bytes(0, payload.lease.router_address), pfx,
+          reinterpret_cast<const char*>(payload.lease.hostname),
+          mac_address_t(payload.lease.host_mac));
+      m_listener.handle_dhcp_event(ev);
+
+      VOM_LOG(log_level_t::INFO) << "DHCP: " << ev->to_string();
+    } else {
+      VOM_LOG(log_level_t::ERROR) << "DHCP: no interface: "
+                                  << payload.lease.sw_if_index;
+    }
+  }
+
+  flush();
 }
 
 std::string
@@ -167,8 +196,38 @@ events_cmd::to_string() const
 {
   return ("dhcp-events");
 }
+
+dump_cmd::dump_cmd()
+{
 }
-};
+
+bool
+dump_cmd::operator==(const dump_cmd& other) const
+{
+  return (true);
+}
+
+rc_t
+dump_cmd::issue(connection& con)
+{
+  m_dump.reset(new msg_t(con.ctx(), std::ref(*this)));
+
+  VAPI_CALL(m_dump->execute());
+
+  wait();
+
+  return rc_t::OK;
+}
+
+std::string
+dump_cmd::to_string() const
+{
+  return ("dhcp-client-dump");
+}
+
+}; // namespace dhcp_client_cmds
+}; // namespace VOM
+
 /*
  * fd.io coding-style-patch-verification: ON
  *
diff --git a/extras/vom/vom/dhcp_config_cmds.hpp b/extras/vom/vom/dhcp_client_cmds.hpp
index 726ff992577..e7db38f4e3b 100644
--- a/extras/vom/vom/dhcp_config_cmds.hpp
+++ b/extras/vom/vom/dhcp_client_cmds.hpp
@@ -13,17 +13,18 @@
  * limitations under the License.
  */
 
-#ifndef __VOM_DHCP_CONFIG_CMDS_H__
-#define __VOM_DHCP_CONFIG_CMDS_H__
+#ifndef __VOM_DHCP_CLIENT_CMDS_H__
+#define __VOM_DHCP_CLIENT_CMDS_H__
 
-#include "vom/dhcp_config.hpp"
+#include "vom/dhcp_client.hpp"
+#include "vom/dump_cmd.hpp"
 #include "vom/event_cmd.hpp"
 
 #include <vapi/dhcp.api.vapi.hpp>
 #include <vapi/vpe.api.vapi.hpp>
 
 namespace VOM {
-namespace dhcp_config_cmds {
+namespace dhcp_client_cmds {
 
 /**
   * A command class that binds the DHCP config to the interface
@@ -125,7 +126,8 @@ public:
   /**
    * Constructor
    */
-  events_cmd(dhcp_config::event_listener& el);
+  events_cmd(dhcp_client::event_listener& el);
+  ~events_cmd();
 
   /**
    * Issue the command to VPP/HW - subscribe to DHCP events
@@ -156,11 +158,45 @@ private:
   /**
    * The listner of this command
    */
-  dhcp_config::event_listener& m_listener;
-};
+  dhcp_client::event_listener& m_listener;
 };
+
+/**
+ * A cmd class that Dumps all the DHCP clients
+ */
+class dump_cmd : public VOM::dump_cmd<vapi::Dhcp_client_dump>
+{
+public:
+  /**
+   * Constructor
+   */
+  dump_cmd();
+  dump_cmd(const dump_cmd& d);
+
+  /**
+   * Issue the command to VPP/HW
+   */
+  rc_t issue(connection& con);
+  /**
+   * convert to string format for debug purposes
+   */
+  std::string to_string() const;
+
+  /**
+   * Comparison operator - only used for UT
+   */
+  bool operator==(const dump_cmd& i) const;
+
+private:
+  /**
+   * HW reutrn code
+   */
+  HW::item<bool> item;
 };
 
+}; // namespace dhcp_client_cmds
+}; // namespace VOM
+
 /*
  * fd.io coding-style-patch-verification: ON
  *
diff --git a/extras/vom/vom/dhcp_config.cpp b/extras/vom/vom/dhcp_config.cpp
deleted file mode 100644
index 7d97fa15d6e..00000000000
--- a/extras/vom/vom/dhcp_config.cpp
+++ /dev/null
@@ -1,194 +0,0 @@
-/*
- * 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/dhcp_config.hpp"
-#include "vom/dhcp_config_cmds.hpp"
-#include "vom/singular_db_funcs.hpp"
-
-namespace VOM {
-/**
- * A DB of all DHCP configs
- */
-singular_db<interface::key_t, dhcp_config> dhcp_config::m_db;
-
-dhcp_config::event_handler dhcp_config::m_evh;
-
-dhcp_config::dhcp_config(const interface& itf,
-                         const std::string& hostname,
-                         bool set_broadcast_flag)
-  : m_itf(itf.singular())
-  , m_hostname(hostname)
-  , m_client_id(l2_address_t::ZERO)
-  , m_set_broadcast_flag(set_broadcast_flag)
-  , m_binding(0)
-{
-}
-
-dhcp_config::dhcp_config(const interface& itf,
-                         const std::string& hostname,
-                         const l2_address_t& client_id,
-                         bool set_broadcast_flag)
-  : m_itf(itf.singular())
-  , m_hostname(hostname)
-  , m_client_id(client_id)
-  , m_set_broadcast_flag(set_broadcast_flag)
-  , m_binding(0)
-{
-}
-
-dhcp_config::dhcp_config(const dhcp_config& o)
-  : m_itf(o.m_itf)
-  , m_hostname(o.m_hostname)
-  , m_client_id(o.m_client_id)
-  , m_set_broadcast_flag(o.m_set_broadcast_flag)
-  , m_binding(0)
-{
-}
-
-dhcp_config::~dhcp_config()
-{
-  sweep();
-
-  // not in the DB anymore.
-  m_db.release(m_itf->key(), this);
-}
-
-bool
-dhcp_config::operator==(const dhcp_config& l) const
-{
-  return ((key() == l.key()) && (m_hostname == l.m_hostname) &&
-          (m_client_id == l.m_client_id));
-}
-
-const dhcp_config::key_t&
-dhcp_config::key() const
-{
-  return (m_itf->key());
-}
-
-void
-dhcp_config::sweep()
-{
-  if (m_binding) {
-    HW::enqueue(
-      new dhcp_config_cmds::unbind_cmd(m_binding, m_itf->handle(), m_hostname));
-  }
-  HW::write();
-}
-
-void
-dhcp_config::dump(std::ostream& os)
-{
-  db_dump(m_db, os);
-}
-
-void
-dhcp_config::replay()
-{
-  if (m_binding) {
-    HW::enqueue(new dhcp_config_cmds::bind_cmd(m_binding, m_itf->handle(),
-                                               m_hostname, m_client_id));
-  }
-}
-
-std::string
-dhcp_config::to_string() const
-{
-  std::ostringstream s;
-  s << "Dhcp-config: " << m_itf->to_string() << " hostname:" << m_hostname
-    << " client_id:[" << m_client_id << "] " << m_binding.to_string();
-
-  return (s.str());
-}
-
-void
-dhcp_config::update(const dhcp_config& desired)
-{
-  /*
- * the desired state is always that the interface should be created
- */
-  if (!m_binding) {
-    HW::enqueue(new dhcp_config_cmds::bind_cmd(m_binding, m_itf->handle(),
-                                               m_hostname, m_client_id));
-  }
-}
-
-std::shared_ptr<dhcp_config>
-dhcp_config::find_or_add(const dhcp_config& temp)
-{
-  return (m_db.find_or_add(temp.m_itf->key(), temp));
-}
-
-std::shared_ptr<dhcp_config>
-dhcp_config::find(const key_t& k)
-{
-  return (m_db.find(k));
-}
-
-std::shared_ptr<dhcp_config>
-dhcp_config::singular() const
-{
-  return find_or_add(*this);
-}
-
-dhcp_config::event_listener::event_listener()
-  : m_status(rc_t::NOOP)
-{
-}
-
-HW::item<bool>&
-dhcp_config::event_listener::status()
-{
-  return (m_status);
-}
-
-dhcp_config::event_handler::event_handler()
-{
-  OM::register_listener(this);
-  inspect::register_handler({ "dhcp" }, "DHCP configurations", this);
-}
-
-void
-dhcp_config::event_handler::handle_replay()
-{
-  m_db.replay();
-}
-
-void
-dhcp_config::event_handler::handle_populate(const client_db::key_t& key)
-{
-  // FIXME
-}
-
-dependency_t
-dhcp_config::event_handler::order() const
-{
-  return (dependency_t::BINDING);
-}
-
-void
-dhcp_config::event_handler::show(std::ostream& os)
-{
-  db_dump(m_db, os);
-}
-}
-
-/*
- * fd.io coding-style-patch-verification: ON
- *
- * Local Variables:
- * eval: (c-set-style "mozilla")
- * End:
- */
diff --git a/extras/vom/vom/l3_binding.cpp b/extras/vom/vom/l3_binding.cpp
index 13bc1ffd575..6b8d36209a7 100644
--- a/extras/vom/vom/l3_binding.cpp
+++ b/extras/vom/vom/l3_binding.cpp
@@ -158,35 +158,6 @@ operator<<(std::ostream& os, const l3_binding::key_t& key)
   return (os);
 }
 
-std::deque<std::shared_ptr<l3_binding>>
-l3_binding::find(const interface& i)
-{
-  /*
- * Loop throught the entire map looking for matching interface.
- * not the most efficient algorithm, but it will do for now. The
- * number of L3 configs is low and this is only called during bootup
- */
-  std::deque<std::shared_ptr<l3_binding>> l3s;
-
-  auto it = m_db.begin();
-
-  while (it != m_db.end()) {
-    /*
-     * The key in the DB is a pair of the interface's name and prefix.
-     * If the keys match, save the L3-config
-     */
-    auto key = it->first;
-
-    if (i.key() == key.first) {
-      l3s.push_back(it->second.lock());
-    }
-
-    ++it;
-  }
-
-  return (l3s);
-}
-
 l3_binding::event_handler::event_handler()
 {
   OM::register_listener(this);
diff --git a/extras/vom/vom/l3_binding.hpp b/extras/vom/vom/l3_binding.hpp
index 0177e56ea2b..a2a46263dbd 100644
--- a/extras/vom/vom/l3_binding.hpp
+++ b/extras/vom/vom/l3_binding.hpp
@@ -95,11 +95,6 @@ public:
   static void dump(std::ostream& os);
 
   /**
-   * Find all bindings in the DB for the interface passed
-   */
-  static std::deque<std::shared_ptr<l3_binding>> find(const interface& i);
-
-  /**
    * Find a binding from its key
    */
   static std::shared_ptr<l3_binding> find(const key_t& k);
diff --git a/extras/vom/vom/neighbour_cmds.cpp b/extras/vom/vom/neighbour_cmds.cpp
index 2f3c200d5fb..63534f3dd94 100644
--- a/extras/vom/vom/neighbour_cmds.cpp
+++ b/extras/vom/vom/neighbour_cmds.cpp
@@ -151,7 +151,11 @@ dump_cmd::issue(connection& con)
 std::string
 dump_cmd::to_string() const
 {
-  return ("neighbour-dump");
+  std::ostringstream s;
+
+  s << "neighbour-dump: " << m_itf.to_string() << " " << m_proto.to_string();
+
+  return (s.str());
 }
 } // namespace neighbour_cmds
 } // namespace vom