Reorganize source tree to use single autotools instance

Change-Id: I7b51f88292e057c6443b12224486f2d0c9f8ae23
Signed-off-by: Damjan Marion <damarion@cisco.com>

6 files changed, 2446 insertions, 0 deletions

diff --git a/src/vnet/dhcp/client.c b/src/vnet/dhcp/client.c
new file mode 100644
index 00000000000..c352e3109ee
--- /dev/null
+++ b/src/vnet/dhcp/client.c
@@ -0,0 +1,1031 @@
+/*
+ * Copyright (c) 2015 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 <vlib/vlib.h>
+#include <vnet/dhcp/proxy.h>
+#include <vnet/fib/fib_table.h>
+
+dhcp_client_main_t dhcp_client_main;
+static u8 * format_dhcp_client_state (u8 * s, va_list * va);
+static vlib_node_registration_t dhcp_client_process_node;
+
+static void 
+dhcp_client_acquire_address (dhcp_client_main_t * dcm, dhcp_client_t * c)
+{
+  /* 
+   * Install any/all info gleaned from dhcp, right here
+   */
+  ip4_add_del_interface_address (dcm->vlib_main, c->sw_if_index,
+                                 (void *) &c->leased_address,
+                                 c->subnet_mask_width, 0 /*is_del*/);
+}
+
+static void 
+dhcp_client_release_address (dhcp_client_main_t * dcm, dhcp_client_t * c)
+{
+  /* 
+   * Remove any/all info gleaned from dhcp, right here. Caller(s)
+   * have not wiped out the info yet.
+   */
+
+  ip4_add_del_interface_address (dcm->vlib_main, c->sw_if_index,
+                                 (void *) &c->leased_address,
+                                 c->subnet_mask_width, 1 /*is_del*/);
+}
+
+static void
+set_l2_rewrite (dhcp_client_main_t * dcm, dhcp_client_t * c)
+{
+  /* Acquire the L2 rewrite string for the indicated sw_if_index */
+  c->l2_rewrite = vnet_build_rewrite_for_sw_interface(
+                      dcm->vnet_main,
+		      c->sw_if_index, 
+		      VNET_LINK_IP4,
+		      0 /* broadcast */);
+}
+
+/* 
+ * dhcp_client_for_us - server-to-client callback.
+ * Called from proxy_node.c:dhcp_proxy_to_client_input().
+ * This function first decides that the packet in question is
+ * actually for the dhcp client code in case we're also acting as
+ * a dhcp proxy. Ay caramba, what a folly!
+ */
+int dhcp_client_for_us (u32 bi, vlib_buffer_t * b,
+                        ip4_header_t * ip,
+                        udp_header_t * udp,
+                        dhcp_header_t * dhcp)
+{
+  dhcp_client_main_t * dcm = &dhcp_client_main;
+  vlib_main_t * vm = dcm->vlib_main;
+  dhcp_client_t * c;
+  uword * p;
+  f64 now = vlib_time_now (dcm->vlib_main);
+  u8 dhcp_message_type = 0;
+  dhcp_option_t * o;
+
+  /* 
+   * Doing dhcp client on this interface? 
+   * Presumably we will always receive dhcp clnt for-us pkts on
+   * the interface that's asking for an address.
+   */
+  p = hash_get (dcm->client_by_sw_if_index, 
+                vnet_buffer(b)->sw_if_index [VLIB_RX]);
+  if (p == 0)
+    return 0;                   /* no */
+  
+  c = pool_elt_at_index (dcm->clients, p[0]);
+
+  /* Mixing dhcp relay and dhcp proxy? DGMS... */
+  if (c->state == DHCP_BOUND && c->retry_count == 0)
+    return 0;
+
+  /* parse through the packet, learn what we can */
+  if (dhcp->your_ip_address.as_u32)
+    c->leased_address.as_u32 = dhcp->your_ip_address.as_u32;
+      
+  o = (dhcp_option_t *) dhcp->options;
+  
+  while (o->option != 0xFF /* end of options */ &&
+         (u8 *) o < (b->data + b->current_data + b->current_length))
+    {
+      switch (o->option)
+        {
+        case 53:                /* dhcp message type */
+          dhcp_message_type = o->data[0];
+          break;
+
+        case 51:                /* lease time */
+          {
+            u32 lease_time_in_seconds = 
+              clib_host_to_net_u32 (o->data_as_u32[0]);
+            c->lease_expires = now + (f64) lease_time_in_seconds;
+            c->lease_lifetime = lease_time_in_seconds;
+            /* Set a sensible default, in case we don't get opt 58 */
+            c->lease_renewal_interval = lease_time_in_seconds / 2;
+          }
+          break;
+
+        case 58:                /* lease renew time in seconds */
+          {
+            u32 lease_renew_time_in_seconds = 
+              clib_host_to_net_u32 (o->data_as_u32[0]);
+            c->lease_renewal_interval = lease_renew_time_in_seconds;
+          }
+          break;
+
+        case 54:                /* dhcp server address */
+          c->dhcp_server.as_u32 = o->data_as_u32[0];
+          break;
+
+        case 1:                 /* subnet mask */
+          {
+            u32 subnet_mask = 
+              clib_host_to_net_u32 (o->data_as_u32[0]);
+            c->subnet_mask_width = count_set_bits (subnet_mask);
+          }
+          break;
+        case 3:                 /* router address */
+          {
+            u32 router_address = o->data_as_u32[0];
+            c->router_address.as_u32 = router_address;
+          }
+          break;
+
+        case 12:                 /* hostname */
+          {
+            /* Replace the existing hostname if necessary */
+            vec_free (c->hostname);
+            vec_validate (c->hostname, o->length - 1);
+            clib_memcpy (c->hostname, o->data, o->length);
+          }
+          break;
+
+          /* $$$$ Your message in this space, parse more options */
+        default:
+          break;
+        }
+
+      o = (dhcp_option_t *) (((uword) o) + (o->length + 2));
+    }
+
+  switch (c->state)
+    {
+    case DHCP_DISCOVER:
+      if (dhcp_message_type != DHCP_PACKET_OFFER)
+        {
+          clib_warning ("sw_if_index %d state %U message type %d",
+                        c->sw_if_index, format_dhcp_client_state,
+                        c->state, dhcp_message_type);
+          c->next_transmit = now + 5.0;
+          break;
+        }
+      /* Received an offer, go send a request */
+      c->state = DHCP_REQUEST;
+      c->retry_count = 0;
+      c->next_transmit = 0;     /* send right now... */
+      /* Poke the client process, which will send the request */
+      vlib_process_signal_event (vm, dhcp_client_process_node.index, 
+                                 EVENT_DHCP_CLIENT_WAKEUP, c - dcm->clients);
+      break;
+
+    case DHCP_BOUND:
+    case DHCP_REQUEST:
+      if (dhcp_message_type != DHCP_PACKET_ACK)
+        {
+          clib_warning ("sw_if_index %d state %U message type %d",
+                        c->sw_if_index, format_dhcp_client_state,
+                        c->state, dhcp_message_type);
+          c->next_transmit = now + 5.0;
+          break;
+        }
+      /* OK, we own the address (etc), add to the routing table(s) */
+      if (c->state == DHCP_REQUEST)
+        {
+          void (*fp)(u32, u32, u8 *, u8, u8 *, u8 *, u8 *) = c->event_callback;
+
+          dhcp_client_acquire_address (dcm, c);
+
+          /*
+           * Configure default IP route:
+           */
+          if (c->router_address.as_u32)
+	    {
+	      fib_prefix_t all_0s =
+	      {
+		  .fp_len = 0,
+		  .fp_addr.ip4.as_u32 = 0x0,
+		  .fp_proto = FIB_PROTOCOL_IP4,
+	      };
+	      ip46_address_t nh =
+	      {
+		  .ip4 = c->router_address,
+	      };
+
+	      fib_table_entry_path_add (fib_table_get_index_for_sw_if_index(
+					   FIB_PROTOCOL_IP4,
+					   c->sw_if_index),
+					&all_0s,
+					FIB_SOURCE_DHCP,
+					FIB_ENTRY_FLAG_NONE,
+					FIB_PROTOCOL_IP4,
+					&nh,
+					c->sw_if_index,
+					~0,
+					1,
+					NULL, // no label stack
+					FIB_ROUTE_PATH_FLAG_NONE);
+	    }
+
+          /*
+           * Call the user's event callback to report DHCP information
+           */
+          if (fp)
+            (*fp) (c->client_index,  /* clinet index */
+                   c->pid,
+                   c->hostname,
+                   0, /* is_ipv6 */
+                   (u8 *)&c->leased_address,  /* host IP address */
+                   (u8 *)&c->router_address,  /* router IP address */
+                   (u8 *)(c->l2_rewrite + 6));/* host MAC address */
+        }
+
+      c->state = DHCP_BOUND;
+      c->retry_count = 0;
+      c->next_transmit = now + (f64) c->lease_renewal_interval;
+      c->lease_expires = now + (f64) c->lease_lifetime;
+      break;
+
+    default:
+      clib_warning ("client %d bogus state %d", 
+                    c - dcm->clients, c->state);
+      break;
+    }
+
+  /* drop the pkt, return 1 */
+  vlib_buffer_free (vm, &bi, 1);
+  return 1;
+}
+
+static void 
+send_dhcp_pkt (dhcp_client_main_t * dcm, dhcp_client_t * c, 
+               dhcp_packet_type_t type, int is_broadcast)
+{
+  vlib_main_t * vm = dcm->vlib_main;
+  vnet_main_t * vnm = dcm->vnet_main;
+  vnet_hw_interface_t * hw = vnet_get_sup_hw_interface (vnm, c->sw_if_index);
+  vnet_sw_interface_t * sup_sw 
+    = vnet_get_sup_sw_interface (vnm, c->sw_if_index);
+  vnet_sw_interface_t * sw = vnet_get_sw_interface (vnm, c->sw_if_index);
+  vlib_buffer_t * b;
+  u32 bi;
+  ip4_header_t * ip;
+  udp_header_t * udp;
+  dhcp_header_t * dhcp;
+  u32 * to_next;
+  vlib_frame_t * f;
+  dhcp_option_t * o;
+  u16 udp_length, ip_length;
+
+  /* Interface(s) down? */
+  if ((hw->flags & VNET_HW_INTERFACE_FLAG_LINK_UP) == 0)
+    return;
+  if ((sup_sw->flags & VNET_SW_INTERFACE_FLAG_ADMIN_UP) == 0)
+    return;
+  if ((sw->flags & VNET_SW_INTERFACE_FLAG_ADMIN_UP) == 0)
+    return;
+
+  if (vlib_buffer_alloc (vm, &bi, 1) != 1) {
+    clib_warning ("buffer allocation failure");
+    c->next_transmit = 0;
+    return;
+  }
+    
+  /* Build a dhcpv4 pkt from whole cloth */
+  b = vlib_get_buffer (vm, bi);
+
+  ASSERT (b->current_data == 0);
+
+  vnet_buffer(b)->sw_if_index[VLIB_RX] = c->sw_if_index;
+  if (is_broadcast) 
+    {
+      f = vlib_get_frame_to_node (vm, hw->output_node_index);
+      vnet_buffer(b)->sw_if_index[VLIB_TX] = c->sw_if_index;
+      clib_memcpy (b->data, c->l2_rewrite, vec_len(c->l2_rewrite));
+      ip = (void *)
+        (((u8 *)vlib_buffer_get_current (b)) + vec_len (c->l2_rewrite));
+    }
+  else
+    {
+      f = vlib_get_frame_to_node (vm, ip4_lookup_node.index);
+      vnet_buffer(b)->sw_if_index[VLIB_TX] = ~0; /* use interface VRF */
+      ip = vlib_buffer_get_current (b);
+    }
+
+  /* Enqueue the packet right now */
+  to_next = vlib_frame_vector_args (f);
+  to_next[0] = bi;
+  f->n_vectors = 1;
+
+  if (is_broadcast)
+    vlib_put_frame_to_node (vm, hw->output_node_index, f);
+  else
+    vlib_put_frame_to_node (vm, ip4_lookup_node.index, f);
+    
+  udp = (udp_header_t *)(ip+1);
+  dhcp = (dhcp_header_t *)(udp+1);
+
+  /* $$$ optimize, maybe */
+  memset (ip, 0, sizeof (*ip) + sizeof (*udp) + sizeof (*dhcp));
+
+  ip->ip_version_and_header_length = 0x45;
+  ip->ttl = 128;
+  ip->protocol = IP_PROTOCOL_UDP;
+  
+  if (is_broadcast)
+    {
+      /* src = 0.0.0.0, dst = 255.255.255.255 */
+      ip->dst_address.as_u32 = ~0;
+    }
+  else
+    {
+      /* Renewing an active lease, plain old ip4 src/dst */
+      ip->src_address.as_u32 = c->leased_address.as_u32;
+      ip->dst_address.as_u32 = c->dhcp_server.as_u32;
+    }
+
+  udp->src_port = clib_host_to_net_u16 (UDP_DST_PORT_dhcp_to_client);
+  udp->dst_port = clib_host_to_net_u16 (UDP_DST_PORT_dhcp_to_server);
+
+  /* Send the interface MAC address */
+  clib_memcpy (dhcp->client_hardware_address, c->l2_rewrite + 6, 6);
+
+  /* Lease renewal, set up client_ip_address */
+  if (is_broadcast == 0)
+    dhcp->client_ip_address.as_u32 = c->leased_address.as_u32;
+
+  dhcp->opcode = 1; /* request, all we send */
+  dhcp->hardware_type = 1; /* ethernet */
+  dhcp->hardware_address_length = 6; 
+  dhcp->transaction_identifier = c->transaction_id;  
+  dhcp->flags = clib_host_to_net_u16(is_broadcast ? DHCP_FLAG_BROADCAST : 0);
+  dhcp->magic_cookie.as_u32 = DHCP_MAGIC;
+  
+  o = (dhcp_option_t * )dhcp->options;
+
+  /* Send option 53, the DHCP message type */
+  o->option = 53;
+  o->length = 1;
+  o->data[0] = type;
+  o = (dhcp_option_t *) (((uword) o) + (o->length + 2));
+
+  /* Send option 57, max msg length */
+  if (0 /* not needed, apparently */)
+    {
+      o->option = 57;
+      o->length = 2;
+      {
+        u16 *o2 = (u16 *) o->data;
+        *o2 = clib_host_to_net_u16 (1152);
+        o = (dhcp_option_t *) (((uword) o) + (o->length + 2));
+      }
+    }
+
+  /*
+   * If server ip address is available with non-zero value,
+   * option 54 (DHCP Server Identifier) is sent.
+   */
+  if (c->dhcp_server.as_u32)
+    {
+      o->option = 54;
+      o->length = 4;
+      clib_memcpy (o->data, &c->dhcp_server.as_u32, 4);
+      o = (dhcp_option_t *) (((uword) o) + (o->length + 2));
+    }
+
+  /* send option 50, requested IP address */
+  if (c->leased_address.as_u32)
+    {
+      o->option = 50;
+      o->length = 4;
+      clib_memcpy (o->data, &c->leased_address.as_u32, 4);
+      o = (dhcp_option_t *) (((uword) o) + (o->length + 2));
+    }
+
+  /* send option 12, host name */
+  if (vec_len (c->hostname))
+    {
+      o->option = 12;
+      o->length = vec_len (c->hostname);
+      clib_memcpy (o->data, c->hostname, vec_len (c->hostname));
+      o = (dhcp_option_t *) (((uword) o) + (o->length + 2));
+    }
+
+  /* $$ maybe send the client s/w version if anyone cares */
+
+  /* 
+   * send option 55, parameter request list
+   * The current list - see below, matches the Linux dhcp client's list
+   * Any specific dhcp server config and/or dhcp server may or may
+   * not yield specific options.
+   */
+  o->option = 55;
+  o->length = vec_len (c->option_55_data);
+  clib_memcpy (o->data, c->option_55_data, vec_len(c->option_55_data));
+  o = (dhcp_option_t *) (((uword) o) + (o->length + 2));
+
+  /* End of list */
+  o->option = 0xff;
+  o->length = 0;
+  o++;
+  
+  b->current_length = ((u8 *)o) - b->data;
+
+  /* fix ip length, checksum and udp length */
+  ip_length = vlib_buffer_length_in_chain (vm, b);
+  if (is_broadcast)
+      ip_length -= vec_len (c->l2_rewrite);
+
+  ip->length = clib_host_to_net_u16(ip_length);
+  ip->checksum = ip4_header_checksum(ip);
+
+  udp_length = ip_length - (sizeof (*ip));
+  udp->length = clib_host_to_net_u16 (udp_length);
+}
+
+static int 
+dhcp_discover_state (dhcp_client_main_t * dcm, dhcp_client_t * c, f64 now)
+{
+  /*
+   * State machine "DISCOVER" state. Send a dhcp discover packet,
+   * eventually back off the retry rate.
+   */
+  send_dhcp_pkt (dcm, c, DHCP_PACKET_DISCOVER, 1 /* is_broadcast */);
+
+  c->retry_count++;
+  if (c->retry_count > 10)
+    c->next_transmit = now + 5.0;
+  else
+    c->next_transmit = now + 1.0;
+  return 0;
+}
+                                
+static int 
+dhcp_request_state (dhcp_client_main_t * dcm, dhcp_client_t * c, f64 now)
+{                              
+  /*
+   * State machine "REQUEST" state. Send a dhcp request packet,
+   * eventually drop back to the discover state.
+   */
+  send_dhcp_pkt (dcm, c, DHCP_PACKET_REQUEST, 1 /* is_broadcast */);
+
+  c->retry_count++;
+  if (c->retry_count > 7 /* lucky you */)
+    {
+      c->state = DHCP_DISCOVER;
+      c->next_transmit = now;
+      c->retry_count = 0;
+      return 1;
+    }
+  c->next_transmit = now + 1.0;
+  return 0;
+}
+
+static int 
+dhcp_bound_state (dhcp_client_main_t * dcm, dhcp_client_t * c, f64 now)
+{
+  /*
+   * State machine "BOUND" state. Send a dhcp request packet,
+   * eventually, when the lease expires, forget the dhcp data
+   * and go back to the stone age.
+   */
+  send_dhcp_pkt (dcm, c, DHCP_PACKET_REQUEST, 0 /* is_broadcast */);
+  
+  c->retry_count++;
+  if (c->retry_count > 10)
+    c->next_transmit = now + 5.0;
+  else
+    c->next_transmit = now + 1.0;
+  
+  if (now > c->lease_expires)
+    {
+      if (c->router_address.as_u32)
+        {
+	  fib_prefix_t all_0s =
+	  {
+	      .fp_len = 0,
+	      .fp_addr.ip4.as_u32 = 0x0,
+	      .fp_proto = FIB_PROTOCOL_IP4,
+	  };
+	  ip46_address_t nh = {
+	      .ip4 = c->router_address,
+	  };
+
+	  fib_table_entry_path_remove(fib_table_get_index_for_sw_if_index(
+					  FIB_PROTOCOL_IP4,
+					  c->sw_if_index),
+				      &all_0s,
+				      FIB_SOURCE_DHCP,
+				      FIB_PROTOCOL_IP4,
+				      &nh,
+				      c->sw_if_index,
+				      ~0,
+				      1,
+				      FIB_ROUTE_PATH_FLAG_NONE);
+	}
+
+      dhcp_client_release_address (dcm, c);
+      c->state = DHCP_DISCOVER;
+      c->next_transmit = now;
+      c->retry_count = 0;
+      /* Wipe out any memory of the address we had... */
+      c->leased_address.as_u32 = 0;
+      c->subnet_mask_width = 0;
+      c->router_address.as_u32 = 0;
+      c->lease_renewal_interval = 0;
+      c->dhcp_server.as_u32 = 0;
+      return 1;
+    }
+  return 0;
+}
+
+static f64 dhcp_client_sm (f64 now, f64 timeout, uword pool_index)
+{
+  dhcp_client_main_t * dcm = &dhcp_client_main;
+  dhcp_client_t * c;
+
+  /* deleted, pooched, yadda yadda yadda */
+  if (pool_is_free_index (dcm->clients, pool_index))
+    return timeout;
+
+  c = pool_elt_at_index (dcm->clients, pool_index);
+
+  /* Time for us to do something with this client? */
+  if (now < c->next_transmit)
+    return timeout;
+
+ again:
+  switch (c->state)
+    {
+    case DHCP_DISCOVER:         /* send a discover */
+      if (dhcp_discover_state (dcm, c, now))
+        goto again;
+      break;
+
+    case DHCP_REQUEST:          /* send a request */
+      if (dhcp_request_state (dcm, c, now))
+        goto again;
+      break;
+      
+    case DHCP_BOUND:            /* bound, renew needed? */
+      if (dhcp_bound_state (dcm, c, now))
+        goto again;
+      break;
+      
+    default:
+      clib_warning ("dhcp client %d bogus state %d", 
+                    c - dcm->clients, c->state);
+      break;
+    }
+  
+  if (c->next_transmit < now + timeout)
+    return c->next_transmit - now;
+
+  return timeout;
+}
+
+static uword
+dhcp_client_process (vlib_main_t * vm,
+                     vlib_node_runtime_t * rt,
+                     vlib_frame_t * f)
+{
+  f64 timeout = 100.0;
+  f64 now;
+  uword event_type;
+  uword * event_data = 0;
+  dhcp_client_main_t * dcm = &dhcp_client_main;
+  dhcp_client_t * c;
+  int i;
+
+  while (1)
+    {
+      vlib_process_wait_for_event_or_clock (vm, timeout);
+
+      event_type = vlib_process_get_events (vm, &event_data);
+
+      now = vlib_time_now (vm);
+
+      switch (event_type)
+        {
+        case EVENT_DHCP_CLIENT_WAKEUP:
+          for (i = 0; i < vec_len (event_data); i++)
+            timeout = dhcp_client_sm (now, timeout, event_data[i]);
+          break;
+
+        case ~0:
+          pool_foreach (c, dcm->clients,
+          ({
+            timeout = dhcp_client_sm (now, timeout, 
+                                          (uword)(c - dcm->clients));
+          }));
+          if (pool_elts (dcm->clients) == 0)
+            timeout = 100.0;
+          break;
+        }
+
+      vec_reset_length (event_data);
+    }
+
+  /* NOTREACHED */
+  return 0;
+}
+
+VLIB_REGISTER_NODE (dhcp_client_process_node,static) = {
+    .function = dhcp_client_process,
+    .type = VLIB_NODE_TYPE_PROCESS,
+    .name = "dhcp-client-process",
+    .process_log2_n_stack_bytes = 16,
+};
+
+static u8 * format_dhcp_client_state (u8 * s, va_list * va)
+{
+  dhcp_client_state_t state = va_arg (*va, dhcp_client_state_t);
+  char * str = "BOGUS!";
+
+  switch (state)
+    {
+#define _(a)                                    \
+    case a:                                     \
+      str = #a;                                 \
+        break;
+      foreach_dhcp_client_state;
+#undef _
+    default:
+      break;
+    }
+
+  s = format (s, "%s", str);
+  return s;
+}
+
+static u8 * format_dhcp_client (u8 * s, va_list * va)
+{
+  dhcp_client_main_t * dcm = va_arg (*va, dhcp_client_main_t *);
+  dhcp_client_t * c = va_arg (*va, dhcp_client_t *);
+  int verbose = va_arg (*va, int);
+
+  s = format (s, "[%d] %U state %U ", c - dcm->clients, 
+              format_vnet_sw_if_index_name, dcm->vnet_main, c->sw_if_index,
+              format_dhcp_client_state, c->state);
+
+  if (c->leased_address.as_u32)
+    s = format (s, "addr %U/%d gw %U\n",
+                format_ip4_address, &c->leased_address, 
+                c->subnet_mask_width, format_ip4_address, &c->router_address);
+  else
+    s = format (s, "no address\n");
+
+  if (verbose)
+    {
+      s = format (s, "retry count %d, next xmt %.2f",
+                  c->retry_count, c->next_transmit);
+    }
+  return s;
+}
+
+static clib_error_t *
+show_dhcp_client_command_fn (vlib_main_t * vm,
+                             unformat_input_t * input,
+                             vlib_cli_command_t * cmd)
+{
+  dhcp_client_main_t * dcm = &dhcp_client_main;
+  dhcp_client_t * c;
+  int verbose = 0;
+  u32 sw_if_index = ~0;
+  uword * p;
+
+  while (unformat_check_input(input) != UNFORMAT_END_OF_INPUT) 
+    {
+      if (unformat (input, "intfc %U", 
+                    unformat_vnet_sw_interface, dcm->vnet_main, 
+                    &sw_if_index))
+        ;
+      else if (unformat (input, "verbose"))
+        verbose = 1;
+      else
+        break;
+    }
+
+  if (sw_if_index != ~0)
+    {
+      p = hash_get (dcm->client_by_sw_if_index, sw_if_index);
+      if (p == 0)
+        return clib_error_return (0, "dhcp client not configured");
+      c = pool_elt_at_index (dcm->clients, p[0]);
+      vlib_cli_output (vm, "%U", format_dhcp_client, dcm, c, verbose);
+      return 0;
+    }
+
+  pool_foreach (c, dcm->clients, 
+  ({
+    vlib_cli_output (vm, "%U", format_dhcp_client, dcm, c, verbose);
+  }));
+  
+  return 0;
+}
+
+VLIB_CLI_COMMAND (show_dhcp_client_command, static) = {
+  .path = "show dhcp client",
+  .short_help = "show dhcp client [intfc <intfc>][verbose]",
+  .function = show_dhcp_client_command_fn,
+};
+
+
+int dhcp_client_add_del (dhcp_client_add_del_args_t * a)
+{
+  dhcp_client_main_t * dcm = &dhcp_client_main;
+  vlib_main_t * vm = dcm->vlib_main;
+  dhcp_client_t * c;
+  uword * p;
+  fib_prefix_t all_1s =
+  {
+      .fp_len = 32,
+      .fp_addr.ip4.as_u32 = 0xffffffff,
+      .fp_proto = FIB_PROTOCOL_IP4,
+  };
+  fib_prefix_t all_0s =
+  {
+      .fp_len = 0,
+      .fp_addr.ip4.as_u32 = 0x0,
+      .fp_proto = FIB_PROTOCOL_IP4,
+  };
+
+  p = hash_get (dcm->client_by_sw_if_index, a->sw_if_index);
+
+  if ((p && a->is_add) || (!p && a->is_add == 0))
+    return VNET_API_ERROR_INVALID_VALUE;
+
+  if (a->is_add)
+    {
+      pool_get (dcm->clients, c);
+      memset (c, 0, sizeof (*c));
+      c->state = DHCP_DISCOVER;
+      c->sw_if_index = a->sw_if_index;
+      c->client_index = a->client_index;
+      c->pid = a->pid;
+      c->event_callback = a->event_callback;
+      c->option_55_data = a->option_55_data;
+      c->hostname = a->hostname;
+      c->client_identifier = a->client_identifier;
+      do {
+        c->transaction_id = random_u32 (&dcm->seed);
+      } while (c->transaction_id == 0);
+      set_l2_rewrite (dcm, c);
+      hash_set (dcm->client_by_sw_if_index, a->sw_if_index, c - dcm->clients);
+
+      /* this add is ref counted by FIB so we can add for each itf */
+      fib_table_entry_special_add(fib_table_get_index_for_sw_if_index(
+				      FIB_PROTOCOL_IP4,
+				      c->sw_if_index),
+				  &all_1s,
+				  FIB_SOURCE_DHCP,
+				  FIB_ENTRY_FLAG_LOCAL,
+				  ADJ_INDEX_INVALID);
+
+     /*
+       * enable the interface to RX IPv4 packets
+       * this is also ref counted
+       */
+      ip4_sw_interface_enable_disable (c->sw_if_index, 1);
+
+      vlib_process_signal_event (vm, dhcp_client_process_node.index, 
+                                 EVENT_DHCP_CLIENT_WAKEUP, c - dcm->clients);
+    }
+  else
+    {
+      c = pool_elt_at_index (dcm->clients, p[0]);
+
+      fib_table_entry_special_remove(fib_table_get_index_for_sw_if_index(
+					 FIB_PROTOCOL_IP4,
+					 c->sw_if_index),
+				     &all_1s,
+				     FIB_SOURCE_DHCP);
+
+      if (c->router_address.as_u32)
+      {
+	  ip46_address_t nh = {
+	      .ip4 = c->router_address,
+	  };
+
+	  fib_table_entry_path_remove(fib_table_get_index_for_sw_if_index(
+					  FIB_PROTOCOL_IP4,
+					  c->sw_if_index),
+				      &all_0s,
+				      FIB_SOURCE_DHCP,
+				      FIB_PROTOCOL_IP4,
+				      &nh,
+				      c->sw_if_index,
+				      ~0,
+				      1,
+				      FIB_ROUTE_PATH_FLAG_NONE);
+      }
+      ip4_sw_interface_enable_disable (c->sw_if_index, 0);
+
+      vec_free (c->option_55_data);
+      vec_free (c->hostname);
+      vec_free (c->client_identifier);
+      vec_free (c->l2_rewrite);
+      hash_unset (dcm->client_by_sw_if_index, c->sw_if_index);
+      pool_put (dcm->clients, c);
+    }
+  return 0;
+}
+
+int
+dhcp_client_config (vlib_main_t * vm,
+                    u32 sw_if_index,
+                    u8 * hostname,
+                    u32 is_add,
+                    u32 client_index,
+                    void * event_callback,
+                    u32 pid)
+{
+  dhcp_client_add_del_args_t _a, *a = &_a;
+  int rv;
+
+  memset (a, 0, sizeof (*a));
+  a->is_add = is_add;
+  a->sw_if_index = sw_if_index;
+  a->client_index = client_index;
+  a->pid = pid;
+  a->event_callback = event_callback;
+  vec_validate(a->hostname, strlen((char *)hostname) - 1);
+  strncpy((char *)a->hostname, (char *)hostname, vec_len(a->hostname));
+  a->client_identifier = format (0, "vpe 1.0%c", 0);
+  /* 
+   * Option 55 request list. These data precisely match
+   * the Ubuntu dhcp client. YMMV.
+   */
+
+  /* Subnet Mask */
+  vec_add1 (a->option_55_data, 1);
+  /* Broadcast address */
+  vec_add1 (a->option_55_data, 28);
+  /* time offset */
+  vec_add1 (a->option_55_data, 2);
+  /* Router */
+  vec_add1 (a->option_55_data, 3);
+  /* Domain Name */
+  vec_add1 (a->option_55_data, 15);
+  /* DNS */
+  vec_add1 (a->option_55_data, 6);
+  /* Domain search */
+  vec_add1 (a->option_55_data, 119);
+  /* Host name */
+  vec_add1 (a->option_55_data, 12);
+  /* NetBIOS name server */
+  vec_add1 (a->option_55_data, 44);
+  /* NetBIOS Scope */
+  vec_add1 (a->option_55_data, 47);
+  /* MTU */
+  vec_add1 (a->option_55_data, 26);
+  /* Classless static route */
+  vec_add1 (a->option_55_data, 121);
+  /* NTP servers */
+  vec_add1 (a->option_55_data, 42);
+
+  rv = dhcp_client_add_del (a);
+
+  switch (rv)
+    {
+    case 0:
+      break;
+
+    case VNET_API_ERROR_INVALID_VALUE:
+
+      vec_free (a->hostname);
+      vec_free (a->client_identifier);
+      vec_free (a->option_55_data);
+
+      if (is_add)
+        clib_warning ("dhcp client already enabled on intf_idx %d",
+                      sw_if_index);
+      else
+        clib_warning ("dhcp client not enabled on on intf_idx %d",
+                      sw_if_index);
+      break;
+
+    default:
+      clib_warning ("dhcp_client_add_del returned %d", rv);
+    }
+
+  return rv;
+}
+
+static clib_error_t *
+dhcp_client_set_command_fn (vlib_main_t * vm,
+                           unformat_input_t * input,
+                           vlib_cli_command_t * cmd)
+{
+
+  dhcp_client_main_t * dcm = &dhcp_client_main;
+  u32 sw_if_index;
+  u8 * hostname = 0;
+  u8 sw_if_index_set = 0;
+  int is_add = 1;
+  dhcp_client_add_del_args_t _a, *a = &_a;
+  int rv;
+
+  while (unformat_check_input(input) != UNFORMAT_END_OF_INPUT) 
+    {
+      if (unformat (input, "intfc %U", 
+                   unformat_vnet_sw_interface, dcm->vnet_main, 
+                   &sw_if_index))
+        sw_if_index_set = 1;
+      else if (unformat (input, "hostname %v", &hostname))
+        ;
+      else if (unformat (input, "del"))
+        is_add = 0;
+      else
+        break;
+    }
+
+  if (sw_if_index_set == 0)
+    return clib_error_return (0, "interface not specified");
+
+  memset (a, 0, sizeof (*a));
+  a->is_add = is_add;
+  a->sw_if_index = sw_if_index;
+  a->hostname = hostname;
+  a->client_identifier = format (0, "vpe 1.0%c", 0);
+
+  /* 
+   * Option 55 request list. These data precisely match
+   * the Ubuntu dhcp client. YMMV.
+   */
+
+  /* Subnet Mask */
+  vec_add1 (a->option_55_data, 1);
+  /* Broadcast address */
+  vec_add1 (a->option_55_data, 28);
+  /* time offset */
+  vec_add1 (a->option_55_data, 2);
+  /* Router */
+  vec_add1 (a->option_55_data, 3);
+  /* Domain Name */
+  vec_add1 (a->option_55_data, 15);
+  /* DNS */
+  vec_add1 (a->option_55_data, 6);
+  /* Domain search */
+  vec_add1 (a->option_55_data, 119);
+  /* Host name */
+  vec_add1 (a->option_55_data, 12);
+  /* NetBIOS name server */
+  vec_add1 (a->option_55_data, 44);
+  /* NetBIOS Scope */
+  vec_add1 (a->option_55_data, 47);
+  /* MTU */
+  vec_add1 (a->option_55_data, 26);
+  /* Classless static route */
+  vec_add1 (a->option_55_data, 121);
+  /* NTP servers */
+  vec_add1 (a->option_55_data, 42);
+
+  rv = dhcp_client_add_del (a);
+
+  switch (rv)
+    {
+    case 0:
+      break;
+
+    case VNET_API_ERROR_INVALID_VALUE:
+
+      vec_free (a->hostname);
+      vec_free (a->client_identifier);
+      vec_free (a->option_55_data);
+      if (is_add)
+        return clib_error_return (0, "dhcp client already enabled on %U", 
+                                  format_vnet_sw_if_index_name, 
+                                  dcm->vnet_main, sw_if_index);
+      else
+        return clib_error_return (0, "dhcp client not enabled on %U", 
+                                  format_vnet_sw_if_index_name, 
+                                  dcm->vnet_main, sw_if_index);
+      break;
+
+    default:
+      vlib_cli_output (vm, "dhcp_client_add_del returned %d", rv);
+    }
+
+  return 0;
+}
+
+VLIB_CLI_COMMAND (dhcp_client_set_command, static) = {
+  .path = "set dhcp client",
+  .short_help = "set dhcp client [del] intfc <interface> [hostname <name>]",
+  .function = dhcp_client_set_command_fn,
+};
+
+static clib_error_t *
+dhcp_client_init (vlib_main_t * vm)
+{
+  dhcp_client_main_t * dcm = &dhcp_client_main;
+
+  dcm->vlib_main = vm;
+  dcm->vnet_main = vnet_get_main();
+  dcm->seed = 0xdeaddabe;
+  return 0;
+}
+
+VLIB_INIT_FUNCTION (dhcp_client_init);
diff --git a/src/vnet/dhcp/client.h b/src/vnet/dhcp/client.h
new file mode 100644
index 00000000000..d15e686b636
--- /dev/null
+++ b/src/vnet/dhcp/client.h
@@ -0,0 +1,118 @@
+/*
+ * Copyright (c) 2015 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.
+ */
+/*
+ * client.h: dhcp client
+ */
+
+#ifndef included_dhcp_client_h
+#define included_dhcp_client_h
+
+#define foreach_dhcp_client_state               \
+_(DHCP_DISCOVER)                                \
+_(DHCP_REQUEST)                                 \
+_(DHCP_BOUND)
+
+typedef enum {
+#define _(a) a,
+  foreach_dhcp_client_state
+#undef _
+} dhcp_client_state_t;
+
+typedef struct {
+  dhcp_client_state_t state;
+
+  /* the interface in question */
+  u32 sw_if_index;
+
+  /* State machine retry counter */
+  u32 retry_count;
+
+  /* Send next pkt at this time */
+  f64 next_transmit;
+  f64 lease_expires;
+
+  /* DHCP transaction ID, a random number */
+  u32 transaction_id;
+
+  /* leased address, other learned info DHCP */
+  ip4_address_t leased_address; /* from your_ip_address field */
+  ip4_address_t dhcp_server;
+  u32 subnet_mask_width;        /* option 1 */
+  ip4_address_t router_address; /* option 3 */
+  u32 lease_renewal_interval;   /* option 51 */
+  u32 lease_lifetime;           /* option 59 */
+
+  /* Requested data (option 55) */
+  u8 * option_55_data;
+
+  u8 * l2_rewrite;
+
+  /* hostname and software client identifiers */
+  u8 * hostname;
+  u8 * client_identifier;       /* software version, e.g. vpe 1.0*/
+
+  /* Information used for event callback */
+  u32 client_index;
+  u32 pid;
+  void * event_callback;
+} dhcp_client_t;
+
+typedef struct {
+  /* DHCP client pool */
+  dhcp_client_t * clients;
+  uword * client_by_sw_if_index;
+  u32 seed;
+
+  /* convenience */
+  vlib_main_t * vlib_main;
+  vnet_main_t * vnet_main;
+} dhcp_client_main_t;
+
+typedef struct {
+  int is_add;
+  u32 sw_if_index;
+
+  /* vectors, consumed by dhcp client code */
+  u8 * hostname;
+  u8 * client_identifier;
+
+  /* Bytes containing requested option numbers */
+  u8 * option_55_data;
+
+  /* Information used for event callback */
+  u32 client_index;
+  u32 pid;
+  void * event_callback;
+} dhcp_client_add_del_args_t;
+
+dhcp_client_main_t dhcp_client_main;
+
+#define EVENT_DHCP_CLIENT_WAKEUP	1
+
+int dhcp_client_for_us (u32 bi0, 
+                          vlib_buffer_t * b0,
+                          ip4_header_t * ip0, 
+                          udp_header_t * u0,
+                          dhcp_header_t * dh0);
+
+int dhcp_client_config (vlib_main_t * vm,
+                        u32 sw_if_index,
+                        u8 * hostname,
+                        u32 is_add,
+                        u32 client_index,
+                        void *event_callback,
+                        u32 pid);
+
+#endif /* included_dhcp_client_h */
diff --git a/src/vnet/dhcp/packet.h b/src/vnet/dhcp/packet.h
new file mode 100644
index 00000000000..267a8eafc93
--- /dev/null
+++ b/src/vnet/dhcp/packet.h
@@ -0,0 +1,61 @@
+#ifndef included_vnet_dhcp_packet_h
+#define included_vnet_dhcp_packet_h
+
+/*
+ * DHCP packet format
+ *
+ * Copyright (c) 2013 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 <vnet/ip/ip4_packet.h>
+
+typedef struct {
+  u8 opcode;                    /* 1 = request, 2 = reply */
+  u8 hardware_type;             /* 1 = ethernet */
+  u8 hardware_address_length;
+  u8 hops;
+  u32 transaction_identifier;
+  u16 seconds;
+  u16 flags;
+#define DHCP_FLAG_BROADCAST (1<<15)
+  ip4_address_t client_ip_address;
+  ip4_address_t your_ip_address; /* use this one */
+  ip4_address_t server_ip_address;
+  ip4_address_t gateway_ip_address; /* use option 3, not this one */
+  u8 client_hardware_address[16];
+  u8 server_name[64];
+  u8 boot_filename[128];
+  ip4_address_t magic_cookie;
+  u8 options[0];
+} dhcp_header_t;
+
+typedef struct {
+  u8 option;
+  u8 length;
+  union {
+    u8 data[0];
+    u32 data_as_u32[0];
+  };
+} __attribute__((packed)) dhcp_option_t;
+
+typedef enum {
+  DHCP_PACKET_DISCOVER=1,
+  DHCP_PACKET_OFFER,
+  DHCP_PACKET_REQUEST,
+  DHCP_PACKET_ACK=5,
+} dhcp_packet_type_t;
+
+/* charming antique: 99.130.83.99 is the dhcp magic cookie */
+#define DHCP_MAGIC (clib_host_to_net_u32(0x63825363))
+
+#endif /* included_vnet_dhcp_packet_h */
diff --git a/src/vnet/dhcp/proxy.h b/src/vnet/dhcp/proxy.h
new file mode 100644
index 00000000000..e12c0d001b5
--- /dev/null
+++ b/src/vnet/dhcp/proxy.h
@@ -0,0 +1,92 @@
+/*
+ * proxy.h: dhcp proxy 
+ *
+ * Copyright (c) 2013 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.
+ */
+
+#ifndef included_dhcp_proxy_h
+#define included_dhcp_proxy_h
+
+#include <vnet/vnet.h>
+#include <vnet/dhcp/packet.h>
+#include <vnet/ethernet/ethernet.h>
+#include <vnet/ip/ip.h>
+#include <vnet/ip/ip4.h>
+#include <vnet/ip/ip4_packet.h>
+#include <vnet/pg/pg.h>
+#include <vnet/ip/format.h>
+#include <vnet/ip/udp.h>
+#include <vnet/dhcp/client.h>
+
+typedef enum {
+#define dhcp_proxy_error(n,s) DHCP_PROXY_ERROR_##n,
+#include <vnet/dhcp/proxy_error.def>
+#undef dhcp_proxy_error
+  DHCP_PROXY_N_ERROR,
+} dhcp_proxy_error_t;
+
+typedef struct {
+  u32 oui;
+  u32 fib_id;
+} vss_id;
+
+typedef union {
+  u8 as_u8[8];
+  vss_id vpn_id;
+} vss_info;
+
+typedef struct {
+  ip4_address_t dhcp_server;
+  ip4_address_t dhcp_src_address;
+  u32 insert_option_82;
+  u32 server_fib_index;
+  u32 valid;
+} dhcp_server_t;
+
+typedef struct {
+  /* Pool of DHCP servers */
+  dhcp_server_t * dhcp_servers;
+
+  /* Pool of selected DHCP server. Zero is the default server */
+  u32 * dhcp_server_index_by_rx_fib_index;
+
+  /* to drop pkts in server-to-client direction */
+  u32 error_drop_node_index;
+
+  vss_info *opt82vss;
+
+  /* hash lookup specific vrf_id -> option 82 vss suboption  */
+  uword * opt82vss_index_by_vrf_id;
+
+  /* convenience */
+  dhcp_client_main_t * dhcp_client_main;
+  vlib_main_t * vlib_main;
+  vnet_main_t * vnet_main;
+} dhcp_proxy_main_t;
+
+dhcp_proxy_main_t dhcp_proxy_main;
+
+int dhcp_proxy_set_server (ip4_address_t *addr, ip4_address_t *src_address,
+                           u32 fib_id, int insert_option_82, int is_del);
+
+int dhcp_proxy_set_server_2 (ip4_address_t *addr, ip4_address_t *src_address,
+                             u32 rx_fib_id,
+                             u32 server_fib_id, 
+                             int insert_option_82, int is_del);
+
+int dhcp_proxy_set_option82_vss(u32 vrf_id,
+                                u32 oui,
+                                u32 fib_id, 
+                                int is_del);
+#endif /* included_dhcp_proxy_h */
diff --git a/src/vnet/dhcp/proxy_error.def b/src/vnet/dhcp/proxy_error.def
new file mode 100644
index 00000000000..6aa06eb5120
--- /dev/null
+++ b/src/vnet/dhcp/proxy_error.def
@@ -0,0 +1,30 @@
+/*
+ * dhcp_proxy_error.def: dhcp proxy errors
+ *
+ * Copyright (c) 2013 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.
+ */
+
+dhcp_proxy_error (NONE, "no error")
+dhcp_proxy_error (NO_SERVER, "no dhcp server configured")
+dhcp_proxy_error (RELAY_TO_SERVER, "DHCP packets relayed to the server")
+dhcp_proxy_error (RELAY_TO_CLIENT, "DHCP packets relayed to clients")
+dhcp_proxy_error (OPTION_82_ERROR, "DHCP failed to insert option 82")
+dhcp_proxy_error (NO_OPTION_82, "DHCP option 82 missing")
+dhcp_proxy_error (BAD_OPTION_82, "Bad DHCP option 82 value")
+dhcp_proxy_error (BAD_FIB_ID, "DHCP option 82 fib-id to fib-index map failure")
+dhcp_proxy_error (NO_INTERFACE_ADDRESS, "DHCP no interface address")
+dhcp_proxy_error (OPTION_82_VSS_NOT_PROCESSED, "DHCP VSS not processed by DHCP server")
+dhcp_proxy_error (BAD_YIADDR, "DHCP packets with bad your_ip_address fields")
+dhcp_proxy_error (BAD_SVR_FIB_OR_ADDRESS, "DHCP packets not from DHCP server or server FIB.")
+dhcp_proxy_error (PKT_TOO_BIG, "DHCP packets which are too big.")
diff --git a/src/vnet/dhcp/proxy_node.c b/src/vnet/dhcp/proxy_node.c
new file mode 100644
index 00000000000..d0d99d7e03b
--- /dev/null
+++ b/src/vnet/dhcp/proxy_node.c
@@ -0,0 +1,1114 @@
+/*
+ * proxy_node.c: dhcp proxy node processing
+ *
+ * Copyright (c) 2013 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 <vlib/vlib.h>
+#include <vnet/pg/pg.h>
+#include <vnet/dhcp/proxy.h>
+#include <vnet/fib/ip4_fib.h>
+
+static char * dhcp_proxy_error_strings[] = {
+#define dhcp_proxy_error(n,s) s,
+#include "proxy_error.def"
+#undef dhcp_proxy_error
+};
+
+#define foreach_dhcp_proxy_to_server_input_next \
+  _ (DROP, "error-drop")			\
+  _ (LOOKUP, "ip4-lookup")			\
+  _ (SEND_TO_CLIENT, "dhcp-proxy-to-client")
+
+typedef enum {
+#define _(s,n) DHCP_PROXY_TO_SERVER_INPUT_NEXT_##s,
+  foreach_dhcp_proxy_to_server_input_next
+#undef _
+  DHCP_PROXY_TO_SERVER_INPUT_N_NEXT,
+} dhcp_proxy_to_server_input_next_t;
+
+typedef struct {
+  /* 0 => to server, 1 => to client */
+  int which; 
+  ip4_address_t trace_ip4_address;
+  u32 error;
+  u32 sw_if_index;
+  u32 original_sw_if_index;
+} dhcp_proxy_trace_t;
+
+#define VPP_DHCP_OPTION82_SUB1_SIZE   6
+#define VPP_DHCP_OPTION82_SUB5_SIZE   6
+#define VPP_DHCP_OPTION82_VSS_SIZE    12
+#define VPP_DHCP_OPTION82_SIZE (VPP_DHCP_OPTION82_SUB1_SIZE + \
+                                VPP_DHCP_OPTION82_SUB5_SIZE + \
+                                VPP_DHCP_OPTION82_VSS_SIZE +3)
+
+vlib_node_registration_t dhcp_proxy_to_server_node;
+vlib_node_registration_t dhcp_proxy_to_client_node;
+
+u8 * format_dhcp_proxy_trace (u8 * s, va_list * args)
+{
+  CLIB_UNUSED (vlib_main_t * vm) = va_arg (*args, vlib_main_t *);
+  CLIB_UNUSED (vlib_node_t * node) = va_arg (*args, vlib_node_t *);
+  dhcp_proxy_trace_t * t = va_arg (*args, dhcp_proxy_trace_t *);
+    
+  if (t->which == 0)
+    s = format (s, "DHCP proxy: sent to server %U\n",
+                format_ip4_address, &t->trace_ip4_address, t->error);
+  else
+    s = format (s, "DHCP proxy: broadcast to client from %U\n",
+                format_ip4_address, &t->trace_ip4_address);
+      
+  if (t->error != (u32)~0)
+    s = format (s, "  error: %s\n", dhcp_proxy_error_strings[t->error]);
+
+  s = format (s, "  original_sw_if_index: %d, sw_if_index: %d\n",
+              t->original_sw_if_index, t->sw_if_index);
+  
+  return s;
+}
+
+u8 * format_dhcp_proxy_header_with_length (u8 * s, va_list * args)
+{
+  dhcp_header_t * h = va_arg (*args, dhcp_header_t *);
+  u32 max_header_bytes = va_arg (*args, u32);
+  u32 header_bytes;
+
+  header_bytes = sizeof (h[0]);
+  if (max_header_bytes != 0 && header_bytes > max_header_bytes)
+    return format (s, "dhcp header truncated");
+
+  s = format (s, "DHCP Proxy");
+
+  return s;
+}
+
+static uword
+dhcp_proxy_to_server_input (vlib_main_t * vm,
+                            vlib_node_runtime_t * node,
+                            vlib_frame_t * from_frame)
+{
+  u32 n_left_from, next_index, * from, * to_next;
+  dhcp_proxy_main_t * dpm = &dhcp_proxy_main;
+  from = vlib_frame_vector_args (from_frame);
+  n_left_from = from_frame->n_vectors;
+  u32 pkts_to_server=0, pkts_to_client=0, pkts_no_server=0;
+  u32 pkts_no_interface_address=0;
+  u32 pkts_too_big=0;
+  ip4_main_t * im = &ip4_main;
+
+  next_index = node->cached_next_index;
+
+  while (n_left_from > 0)
+    {
+      u32 n_left_to_next;
+
+      vlib_get_next_frame (vm, node, next_index,
+			   to_next, n_left_to_next);
+
+      while (n_left_from > 0 && n_left_to_next > 0)
+	{
+	  u32 bi0;
+	  vlib_buffer_t * b0;
+          udp_header_t * u0;
+	  dhcp_header_t * h0;
+          ip4_header_t * ip0;
+	  u32 next0;
+          u32 old0, new0;
+          ip_csum_t sum0;
+          u32 error0 = (u32) ~0;
+          u32 sw_if_index = 0;
+          u32 original_sw_if_index = 0;
+          u8  *end = NULL;
+          u32 fib_index, server_index;
+          dhcp_server_t * server;
+          u32 rx_sw_if_index;
+
+	  bi0 = from[0];
+	  to_next[0] = bi0;
+	  from += 1;
+	  to_next += 1;
+	  n_left_from -= 1;
+	  n_left_to_next -= 1;
+
+	  b0 = vlib_get_buffer (vm, bi0);
+
+          h0 = vlib_buffer_get_current (b0);
+
+          /* 
+           * udp_local hands us the DHCP header, need udp hdr, 
+           * ip hdr to relay to server
+           */
+          vlib_buffer_advance (b0, -(sizeof(*u0)));
+	  u0 = vlib_buffer_get_current (b0);
+
+          /* This blows. Return traffic has src_port = 67, dst_port = 67 */
+          if (u0->src_port == clib_net_to_host_u16(UDP_DST_PORT_dhcp_to_server))
+            {
+              vlib_buffer_advance (b0, sizeof(*u0));
+              next0 = DHCP_PROXY_TO_SERVER_INPUT_NEXT_SEND_TO_CLIENT;
+              error0 = 0;
+              pkts_to_client++;
+              goto do_enqueue;
+            }
+
+          rx_sw_if_index = vnet_buffer(b0)->sw_if_index[VLIB_RX];
+
+          fib_index = im->fib_index_by_sw_if_index [rx_sw_if_index];
+
+          if (fib_index < vec_len(dpm->dhcp_server_index_by_rx_fib_index))
+            server_index = dpm->dhcp_server_index_by_rx_fib_index[fib_index];
+          else
+            server_index = 0;
+          
+          if (PREDICT_FALSE (pool_is_free_index (dpm->dhcp_servers, 
+                                                 server_index)))
+            {
+            no_server:
+              error0 = DHCP_PROXY_ERROR_NO_SERVER;
+              next0 = DHCP_PROXY_TO_SERVER_INPUT_NEXT_DROP;
+              pkts_no_server++;
+              goto do_trace;
+            }
+          
+          server = pool_elt_at_index (dpm->dhcp_servers, server_index);
+          if (server->valid == 0)
+            goto no_server;
+
+          vlib_buffer_advance (b0, -(sizeof(*ip0)));
+          ip0 = vlib_buffer_get_current (b0);
+
+          /* disable UDP checksum */
+          u0->checksum = 0;
+          sum0 = ip0->checksum;
+          old0 = ip0->dst_address.as_u32;
+          new0 = server->dhcp_server.as_u32;
+          ip0->dst_address.as_u32 = server->dhcp_server.as_u32;
+          sum0 = ip_csum_update (sum0, old0, new0, 
+                                ip4_header_t /* structure */, 
+                                dst_address /* changed member */);
+          ip0->checksum = ip_csum_fold (sum0);
+
+          sum0 = ip0->checksum;
+          old0 = ip0->src_address.as_u32;
+          new0 = server->dhcp_src_address.as_u32;
+          ip0->src_address.as_u32 = new0;
+          sum0 = ip_csum_update (sum0, old0, new0, 
+                                ip4_header_t /* structure */, 
+                                src_address /* changed member */);
+          ip0->checksum = ip_csum_fold (sum0);
+
+          /* Send to DHCP server via the configured FIB */
+          vnet_buffer(b0)->sw_if_index[VLIB_TX] =
+            server->server_fib_index;
+
+          h0->gateway_ip_address.as_u32 = server->dhcp_src_address.as_u32;
+          pkts_to_server++;
+
+          if (server->insert_option_82) 
+            {
+              u32 fib_index, fib_id, opt82_fib_id=0, opt82_oui=0;
+	      ip4_fib_t * fib;
+              dhcp_option_t *o = (dhcp_option_t *) h0->options;
+              u32 len = 0;
+              vlib_buffer_free_list_t *fl;
+              
+              fib_index = im->fib_index_by_sw_if_index 
+                [vnet_buffer(b0)->sw_if_index[VLIB_RX]];
+	      fib = ip4_fib_get (fib_index);
+	      fib_id = fib->table_id;
+
+              end = b0->data + b0->current_data + b0->current_length;
+              /* TLVs are not performance-friendly... */
+              while  (o->option != 0xFF /* end of options */ && (u8 *)o < end) 
+                  o = (dhcp_option_t *) (((uword) o) + (o->length + 2));
+
+              fl = vlib_buffer_get_free_list (vm, b0->free_list_index);
+              // start write at (option*)o, some packets have padding
+              if (((u8 *)o - (u8 *)b0->data + VPP_DHCP_OPTION82_SIZE) > fl->n_data_bytes)
+                {
+                  next0 = DHCP_PROXY_TO_SERVER_INPUT_NEXT_DROP;
+                  pkts_too_big++;
+                  goto do_trace;
+                }
+
+              if ((o->option == 0xFF)  && ((u8 *)o <= end))
+                {  
+                  vnet_main_t *vnm = vnet_get_main();   
+                  u16 old_l0, new_l0;
+                  ip4_address_t _ia0, * ia0 = &_ia0;
+                  uword  *p_vss;
+                  vss_info *vss;
+                  vnet_sw_interface_t *swif;
+                  sw_if_index = 0;
+                  original_sw_if_index = 0;
+                  
+                  original_sw_if_index = sw_if_index = 
+                      vnet_buffer(b0)->sw_if_index[VLIB_RX];
+                  swif = vnet_get_sw_interface (vnm, sw_if_index);
+                  if (swif->flags & VNET_SW_INTERFACE_FLAG_UNNUMBERED)
+                      sw_if_index = swif->unnumbered_sw_if_index;
+                  
+                  p_vss = hash_get (dpm->opt82vss_index_by_vrf_id,
+                                    fib_id);
+                  if (p_vss) 
+                    {
+                      vss = pool_elt_at_index (dpm->opt82vss, p_vss[0]);
+                      opt82_oui =  vss->vpn_id.oui;
+                      opt82_fib_id =  vss->vpn_id.fib_id;
+                    }
+                  /* 
+                   * Get the first ip4 address on the [client-side] 
+                   * RX interface, if not unnumbered. otherwise use
+                   * the loopback interface's ip address.
+                   */
+                  ia0 = ip4_interface_first_address(&ip4_main, sw_if_index, 0);
+                  
+                  if (ia0 == 0)
+                    {
+                      error0 = DHCP_PROXY_ERROR_NO_INTERFACE_ADDRESS;
+                      next0 = DHCP_PROXY_TO_SERVER_INPUT_NEXT_DROP;
+                      pkts_no_interface_address++;
+                      goto do_trace;
+                    }
+
+                  /* Add option 82 */
+                  o->option = 82;   /* option 82 */
+                  o->length = 12;   /* 12 octets to follow */
+                  o->data[0] = 1;   /* suboption 1, circuit ID (=FIB id) */
+                  o->data[1] = 4;   /* length of suboption */
+                  o->data[2] = (original_sw_if_index >> 24) & 0xFF;
+                  o->data[3] = (original_sw_if_index >> 16) & 0xFF;
+                  o->data[4] = (original_sw_if_index >> 8)  & 0xFF;
+                  o->data[5] = (original_sw_if_index >> 0)  & 0xFF;
+		  o->data[6] = 5; /* suboption 5 (client RX intfc address) */
+		  o->data[7] = 4; /* length 4 */
+		  o->data[8] = ia0->as_u8[0];
+		  o->data[9] = ia0->as_u8[1];
+		  o->data[10] = ia0->as_u8[2];
+		  o->data[11] = ia0->as_u8[3];
+                  o->data[12] = 0xFF;
+                  if (opt82_oui !=0 || opt82_fib_id != 0)
+                    {
+                      o->data[12] = 151; /* vss suboption */
+                      if (255 == opt82_fib_id) {
+                          o->data[13] = 1;   /* length */
+                          o->data[14] = 255;   /* vss option type */
+                          o->data[15] = 152; /* vss control suboption */
+                          o->data[16] = 0;   /* length */
+                          /* and a new "end-of-options" option (0xff) */
+                          o->data[17] = 0xFF;
+                          o->length += 5;
+                      } else {
+                          o->data[13] = 8;   /* length */
+                          o->data[14] = 1;   /* vss option type */
+                          o->data[15] = (opt82_oui >> 16) & 0xff;
+                          o->data[16] = (opt82_oui >> 8) & 0xff;
+                          o->data[17] = (opt82_oui ) & 0xff;
+                          o->data[18] = (opt82_fib_id >> 24) & 0xff;
+                          o->data[19] = (opt82_fib_id >> 16) & 0xff;
+                          o->data[20] = (opt82_fib_id >> 8) & 0xff;
+                          o->data[21] = (opt82_fib_id) & 0xff;
+                          o->data[22] = 152; /* vss control suboption */
+                          o->data[23] = 0;   /* length */
+                          
+                          /* and a new "end-of-options" option (0xff) */
+                          o->data[24] = 0xFF;
+                          o->length += 12;
+                      }
+                  }
+
+                  len = o->length + 3;
+                  b0->current_length += len;
+                  /* Fix IP header length and checksum */
+                  old_l0 = ip0->length;
+                  new_l0 = clib_net_to_host_u16 (old_l0);
+                  new_l0 += len;
+                  new_l0 = clib_host_to_net_u16 (new_l0);
+                  ip0->length = new_l0;
+                  sum0 = ip0->checksum;
+                  sum0 = ip_csum_update (sum0, old_l0, new_l0, ip4_header_t,
+                                         length /* changed member */);
+                  ip0->checksum = ip_csum_fold (sum0);
+
+                  /* Fix UDP length */
+                  new_l0 = clib_net_to_host_u16 (u0->length);
+                  new_l0 += len;
+                  u0->length = clib_host_to_net_u16 (new_l0);
+                } else {
+                  vlib_node_increment_counter 
+                      (vm, dhcp_proxy_to_server_node.index,
+                       DHCP_PROXY_ERROR_OPTION_82_ERROR, 1);
+                }
+            }
+          
+          next0 = DHCP_PROXY_TO_SERVER_INPUT_NEXT_LOOKUP;
+
+        do_trace:
+          if (PREDICT_FALSE(b0->flags & VLIB_BUFFER_IS_TRACED)) 
+            {
+               dhcp_proxy_trace_t *tr = vlib_add_trace (vm, node, 
+                                                        b0, sizeof (*tr));
+               tr->which = 0; /* to server */
+               tr->error = error0;
+               tr->original_sw_if_index = original_sw_if_index;
+               tr->sw_if_index = sw_if_index;
+               if (next0 == DHCP_PROXY_TO_SERVER_INPUT_NEXT_LOOKUP)
+                 tr->trace_ip4_address.as_u32 = server->dhcp_server.as_u32;
+            }
+
+        do_enqueue:
+	  vlib_validate_buffer_enqueue_x1 (vm, node, next_index,
+					   to_next, n_left_to_next,
+					   bi0, next0);
+	}
+
+      vlib_put_next_frame (vm, node, next_index, n_left_to_next);
+    }
+
+  vlib_node_increment_counter (vm, dhcp_proxy_to_server_node.index,
+                               DHCP_PROXY_ERROR_RELAY_TO_CLIENT,
+                               pkts_to_client);
+  vlib_node_increment_counter (vm, dhcp_proxy_to_server_node.index,
+                               DHCP_PROXY_ERROR_RELAY_TO_SERVER,
+                               pkts_to_server);
+  vlib_node_increment_counter (vm, dhcp_proxy_to_server_node.index,
+                               DHCP_PROXY_ERROR_NO_SERVER,
+                               pkts_no_server);
+  vlib_node_increment_counter (vm, dhcp_proxy_to_server_node.index,
+                               DHCP_PROXY_ERROR_NO_INTERFACE_ADDRESS,
+                               pkts_no_interface_address);
+ vlib_node_increment_counter (vm, dhcp_proxy_to_server_node.index,
+                              DHCP_PROXY_ERROR_PKT_TOO_BIG,
+                              pkts_too_big);
+  return from_frame->n_vectors;
+}
+
+VLIB_REGISTER_NODE (dhcp_proxy_to_server_node) = {
+  .function = dhcp_proxy_to_server_input,
+  .name = "dhcp-proxy-to-server",
+  /* Takes a vector of packets. */
+  .vector_size = sizeof (u32),
+
+  .n_errors = DHCP_PROXY_N_ERROR,
+  .error_strings = dhcp_proxy_error_strings,
+
+  .n_next_nodes = DHCP_PROXY_TO_SERVER_INPUT_N_NEXT,
+  .next_nodes = {
+#define _(s,n) [DHCP_PROXY_TO_SERVER_INPUT_NEXT_##s] = n,
+    foreach_dhcp_proxy_to_server_input_next
+#undef _
+  },
+
+  .format_buffer = format_dhcp_proxy_header_with_length,
+  .format_trace = format_dhcp_proxy_trace,
+#if 0
+  .unformat_buffer = unformat_dhcp_proxy_header,
+#endif
+};
+
+static uword
+dhcp_proxy_to_client_input (vlib_main_t * vm,
+                            vlib_node_runtime_t * node,
+                            vlib_frame_t * from_frame)
+{
+  u32 n_left_from, * from;
+  ethernet_main_t *em = ethernet_get_main (vm);
+  dhcp_proxy_main_t * dpm = &dhcp_proxy_main;
+  vnet_main_t * vnm = vnet_get_main();
+  ip4_main_t * im = &ip4_main;
+
+  from = vlib_frame_vector_args (from_frame);
+  n_left_from = from_frame->n_vectors;
+
+  while (n_left_from > 0)
+    {
+      u32 bi0;
+      vlib_buffer_t * b0;
+      udp_header_t * u0;
+      dhcp_header_t * h0;
+      ip4_header_t * ip0 = 0;
+      ip4_address_t * ia0 = 0;
+      u32 old0, new0;
+      ip_csum_t sum0;
+      ethernet_interface_t *ei0;
+      ethernet_header_t *mac0;
+      vnet_hw_interface_t *hi0;
+      vlib_frame_t *f0;
+      u32 * to_next0;
+      u32 sw_if_index = ~0;
+      vnet_sw_interface_t *si0;
+      u32 error0 = (u32)~0;
+      vnet_sw_interface_t *swif;
+      u32 server_index;
+      u32 fib_index;
+      dhcp_server_t * server;
+      u32 original_sw_if_index = (u32) ~0;
+          
+      bi0 = from[0];
+      from += 1;
+      n_left_from -= 1;
+
+      b0 = vlib_get_buffer (vm, bi0);
+      h0 = vlib_buffer_get_current (b0);
+
+      /* 
+       * udp_local hands us the DHCP header, need udp hdr, 
+       * ip hdr to relay to client
+       */
+      vlib_buffer_advance (b0, -(sizeof(*u0)));
+      u0 = vlib_buffer_get_current (b0);
+
+      vlib_buffer_advance (b0, -(sizeof(*ip0)));
+      ip0 = vlib_buffer_get_current (b0);
+
+      /* Consumed by dhcp client code? */
+      if (dhcp_client_for_us (bi0, b0, ip0, u0, h0))
+          continue;
+
+      if (1 /* dpm->insert_option_82 */)
+        {
+          dhcp_option_t *o = (dhcp_option_t *) h0->options;
+          dhcp_option_t *sub;
+              
+          /* Parse through TLVs looking for option 82.
+             The circuit-ID is the FIB number we need
+             to track down the client-facing interface */
+
+          while (o->option != 0xFF /* end of options */ &&
+                 (u8 *) o < (b0->data + b0->current_data + b0->current_length))
+            {
+              if (o->option == 82)
+                {
+                    u32 vss_exist = 0;
+                    u32 vss_ctrl = 0;
+                    sub = (dhcp_option_t *) &o->data[0];
+                    while (sub->option != 0xFF /* end of options */ &&
+                           (u8 *) sub < (u8 *)(o + o->length)) {
+                        /* If this is one of ours, it will have
+                           total length 12, circuit-id suboption type,
+                           and the sw_if_index */
+                        if (sub->option == 1 && sub->length == 4)
+                          {
+                            sw_if_index = (o->data[2] << 24)
+                                | (o->data[3] << 16)
+                                | (o->data[4] << 8)
+                                | (o->data[5]);
+                          } else if (sub->option == 151 &&
+                                     sub->length == 7 &&
+                                     sub->data[0] == 1)
+                            vss_exist = 1;
+                        else if (sub->option == 152 && sub->length == 0)
+                            vss_ctrl = 1;
+                        sub = (dhcp_option_t *) 
+                          (((uword) sub) + (sub->length + 2));
+                    }
+                    if (vss_ctrl && vss_exist)
+                      vlib_node_increment_counter 
+                        (vm, dhcp_proxy_to_client_node.index,
+                         DHCP_PROXY_ERROR_OPTION_82_VSS_NOT_PROCESSED, 1);
+
+                }
+              o = (dhcp_option_t *) (((uword) o) + (o->length + 2));
+            }
+        }
+
+      if (sw_if_index == (u32)~0)
+        {
+          error0 = DHCP_PROXY_ERROR_NO_OPTION_82;
+          
+        drop_packet:
+          vlib_node_increment_counter (vm, dhcp_proxy_to_client_node.index,
+                                       error0, 1);
+          f0 = vlib_get_frame_to_node (vm, dpm->error_drop_node_index);
+          to_next0 = vlib_frame_vector_args (f0);
+          to_next0[0] = bi0;
+          f0->n_vectors = 1;
+          vlib_put_frame_to_node (vm, dpm->error_drop_node_index, f0);
+          goto do_trace;
+        }
+      
+
+      if (sw_if_index >= vec_len (im->fib_index_by_sw_if_index))
+        {
+          error0 = DHCP_PROXY_ERROR_BAD_OPTION_82;
+          goto drop_packet;
+        }
+
+      fib_index = im->fib_index_by_sw_if_index [sw_if_index];
+
+      if (fib_index < vec_len(dpm->dhcp_server_index_by_rx_fib_index))
+        server_index = dpm->dhcp_server_index_by_rx_fib_index[fib_index];
+      else
+        server_index = 0;
+
+      if (PREDICT_FALSE (pool_is_free_index (dpm->dhcp_servers, 
+                                             server_index)))
+        {
+          error0 = DHCP_PROXY_ERROR_BAD_OPTION_82;
+          goto drop_packet;
+        }
+      
+      server = pool_elt_at_index (dpm->dhcp_servers, server_index);
+      if (server->valid == 0)
+        {
+          error0 = DHCP_PROXY_ERROR_NO_SERVER;
+          goto drop_packet;
+        }
+
+      if (ip0->src_address.as_u32 != server->dhcp_server.as_u32)
+        {             
+          error0 = DHCP_PROXY_ERROR_BAD_SVR_FIB_OR_ADDRESS;
+          goto drop_packet;
+        }
+
+      vnet_buffer (b0)->sw_if_index[VLIB_TX] = sw_if_index;
+
+      swif = vnet_get_sw_interface (vnm, sw_if_index);
+      original_sw_if_index = sw_if_index;
+      if (swif->flags & VNET_SW_INTERFACE_FLAG_UNNUMBERED)
+          sw_if_index = swif->unnumbered_sw_if_index;
+
+      ia0 = ip4_interface_first_address (&ip4_main, sw_if_index, 0);
+      if (ia0 == 0)
+        {
+          error0 = DHCP_PROXY_ERROR_NO_INTERFACE_ADDRESS;
+          goto drop_packet;
+        }
+
+      u0->checksum = 0;
+      u0->dst_port = clib_net_to_host_u16 (UDP_DST_PORT_dhcp_to_client);
+      sum0 = ip0->checksum;
+      old0 = ip0->dst_address.as_u32;
+      new0 = 0xFFFFFFFF;
+      ip0->dst_address.as_u32 = new0;
+      sum0 = ip_csum_update (sum0, old0, new0, 
+                            ip4_header_t /* structure */, 
+                            dst_address /* offset of changed member */);
+      ip0->checksum = ip_csum_fold (sum0);
+
+      sum0 = ip0->checksum;
+      old0 = ip0->src_address.as_u32;
+      new0 = ia0->as_u32;
+      ip0->src_address.as_u32 = new0;
+      sum0 = ip_csum_update (sum0, old0, new0, 
+                            ip4_header_t /* structure */, 
+                            src_address /* offset of changed member */);
+      ip0->checksum = ip_csum_fold (sum0);
+
+      vlib_buffer_advance (b0, -(sizeof(ethernet_header_t)));
+      si0 = vnet_get_sw_interface (vnm, original_sw_if_index);
+      if (si0->type == VNET_SW_INTERFACE_TYPE_SUB)
+	  vlib_buffer_advance (b0, -4 /* space for VLAN tag */);
+
+      mac0 = vlib_buffer_get_current (b0);
+
+      hi0 = vnet_get_sup_hw_interface (vnm, original_sw_if_index);
+      ei0 = pool_elt_at_index (em->interfaces, hi0->hw_instance);
+      clib_memcpy (mac0->src_address, ei0->address, sizeof (ei0->address));
+      memset (mac0->dst_address, 0xff, sizeof (mac0->dst_address));
+      mac0->type = (si0->type == VNET_SW_INTERFACE_TYPE_SUB) ?
+	clib_net_to_host_u16(0x8100) : clib_net_to_host_u16 (0x0800);
+
+      if (si0->type == VNET_SW_INTERFACE_TYPE_SUB)
+	{
+	  u32 * vlan_tag = (u32 *)(mac0+1);
+	  u32 tmp;
+	  tmp = (si0->sub.id << 16) | 0x0800;
+	  *vlan_tag = clib_host_to_net_u32 (tmp);
+	}
+
+      /* $$$ This needs to be rewritten, for sure */
+      f0 = vlib_get_frame_to_node (vm, hi0->output_node_index);
+      to_next0 = vlib_frame_vector_args (f0);
+      to_next0[0] = bi0;
+      f0->n_vectors = 1;
+      vlib_put_frame_to_node (vm, hi0->output_node_index, f0);
+
+    do_trace:
+      if (PREDICT_FALSE(b0->flags & VLIB_BUFFER_IS_TRACED)) 
+        {
+          dhcp_proxy_trace_t *tr = vlib_add_trace (vm, node, 
+                                                   b0, sizeof (*tr));
+          tr->which = 1; /* to client */
+          tr->trace_ip4_address.as_u32 = ia0 ? ia0->as_u32 : 0;
+          tr->error = error0;
+          tr->original_sw_if_index = original_sw_if_index;
+          tr->sw_if_index = sw_if_index;
+        }
+    }
+  return from_frame->n_vectors;
+}
+
+VLIB_REGISTER_NODE (dhcp_proxy_to_client_node) = {
+  .function = dhcp_proxy_to_client_input,
+  .name = "dhcp-proxy-to-client",
+  /* Takes a vector of packets. */
+  .vector_size = sizeof (u32),
+
+  .n_errors = DHCP_PROXY_N_ERROR,
+  .error_strings = dhcp_proxy_error_strings,
+  .format_buffer = format_dhcp_proxy_header_with_length,
+  .format_trace = format_dhcp_proxy_trace,
+#if 0
+  .unformat_buffer = unformat_dhcp_proxy_header,
+#endif
+};
+
+clib_error_t * dhcp_proxy_init (vlib_main_t * vm)
+{
+  dhcp_proxy_main_t * dm = &dhcp_proxy_main;
+  vlib_node_t * error_drop_node;
+  dhcp_server_t * server;
+
+  dm->vlib_main = vm;
+  dm->vnet_main = vnet_get_main();
+  error_drop_node = vlib_get_node_by_name (vm, (u8 *) "error-drop");
+  dm->error_drop_node_index = error_drop_node->index;
+
+  dm->opt82vss_index_by_vrf_id = hash_create (0, sizeof (uword));
+
+  udp_register_dst_port (vm, UDP_DST_PORT_dhcp_to_client, 
+                         dhcp_proxy_to_client_node.index, 1 /* is_ip4 */);
+
+  udp_register_dst_port (vm, UDP_DST_PORT_dhcp_to_server, 
+                         dhcp_proxy_to_server_node.index, 1 /* is_ip4 */);
+
+  /* Create the default server, don't mark it valid */
+  pool_get (dm->dhcp_servers, server);
+  memset (server, 0, sizeof (*server));
+
+  return 0;
+}
+
+VLIB_INIT_FUNCTION (dhcp_proxy_init);
+
+int dhcp_proxy_set_server_2 (ip4_address_t *addr, ip4_address_t *src_address,
+                             u32 rx_fib_id,
+                             u32 server_fib_id, 
+                             int insert_option_82, int is_del)
+{
+  dhcp_proxy_main_t * dpm = &dhcp_proxy_main;
+  dhcp_server_t * server = 0;
+  u32 server_index = 0;
+  u32 rx_fib_index = 0;
+
+  if (addr->as_u32 == 0)
+    return VNET_API_ERROR_INVALID_DST_ADDRESS;
+  
+  if (src_address->as_u32 == 0)
+    return VNET_API_ERROR_INVALID_SRC_ADDRESS;
+
+  rx_fib_index = fib_table_find_or_create_and_lock(FIB_PROTOCOL_IP4,
+                                                   rx_fib_id);
+
+  if (rx_fib_id == 0)
+    {
+      server = pool_elt_at_index (dpm->dhcp_servers, 0);
+      
+      if (is_del)
+        {
+          memset (server, 0, sizeof (*server));
+          return 0;
+        }
+      goto initialize_it;
+    }
+
+  if (is_del)
+    {
+      if (rx_fib_index >= vec_len(dpm->dhcp_server_index_by_rx_fib_index))
+        return VNET_API_ERROR_NO_SUCH_ENTRY;
+      
+      server_index = dpm->dhcp_server_index_by_rx_fib_index[rx_fib_index];
+      ASSERT(server_index > 0);
+
+      /* Use the default server again.  */
+      dpm->dhcp_server_index_by_rx_fib_index[rx_fib_index] = 0;
+      server = pool_elt_at_index (dpm->dhcp_servers, server_index);
+      memset (server, 0, sizeof (*server));
+      pool_put (dpm->dhcp_servers, server);
+      return 0;
+    }
+
+  if (rx_fib_index < vec_len(dpm->dhcp_server_index_by_rx_fib_index))
+    {
+      server_index = dpm->dhcp_server_index_by_rx_fib_index[rx_fib_index];
+      if (server_index != 0)
+        {
+          server = pool_elt_at_index (dpm->dhcp_servers, server_index);
+          goto initialize_it;
+        }
+    }
+
+  pool_get (dpm->dhcp_servers, server);
+  
+ initialize_it:
+
+  server->dhcp_server.as_u32 = addr->as_u32;
+  server->server_fib_index = 
+      fib_table_find_or_create_and_lock(FIB_PROTOCOL_IP4,
+	  				server_fib_id);
+  server->dhcp_src_address.as_u32 = src_address->as_u32;
+  server->insert_option_82 = insert_option_82;
+  server->valid = 1;
+  if (rx_fib_index)
+    {
+      vec_validate (dpm->dhcp_server_index_by_rx_fib_index, rx_fib_index);
+      dpm->dhcp_server_index_by_rx_fib_index[rx_fib_index] = 
+        server - dpm->dhcp_servers;
+    }
+
+  return 0;
+}
+
+/* Old API, manipulates the default server (only) */
+int dhcp_proxy_set_server (ip4_address_t *addr, ip4_address_t *src_address,
+                           u32 fib_id, int insert_option_82, int is_del)
+{
+  return dhcp_proxy_set_server_2 (addr, src_address, 0 /* rx_fib_id */,
+                                  fib_id /* server_fib_id */, 
+                                  insert_option_82, is_del);
+}
+
+
+static clib_error_t *
+dhcp_proxy_set_command_fn (vlib_main_t * vm,
+                           unformat_input_t * input,
+                           vlib_cli_command_t * cmd)
+{
+  ip4_address_t server_addr, src_addr;
+  u32 server_fib_id = 0, rx_fib_id = 0;
+  int is_del = 0;
+  int add_option_82 = 0;
+  int set_src = 0, set_server = 0;
+  
+  while (unformat_check_input(input) != UNFORMAT_END_OF_INPUT) 
+    {
+      if (unformat (input, "server %U", 
+                    unformat_ip4_address, &server_addr)) 
+        set_server = 1;
+      else if (unformat (input, "server-fib-id %d", &server_fib_id))
+        ;
+      else if (unformat (input, "rx-fib-id %d", &rx_fib_id))
+        ;
+      else if (unformat(input, "src-address %U", 
+			unformat_ip4_address, &src_addr))
+        set_src = 1;
+      else if (unformat (input, "add-option-82")
+               || unformat (input, "insert-option-82"))
+        add_option_82 = 1;
+      else if (unformat (input, "delete") ||
+               unformat (input, "del"))
+        is_del = 1;
+      else
+        break;
+    }
+
+  if (is_del || (set_server && set_src))
+    {
+      int rv;
+
+      rv = dhcp_proxy_set_server_2 (&server_addr, &src_addr, rx_fib_id, 
+                                    server_fib_id, add_option_82, is_del);
+      switch (rv)
+        {
+        case 0:
+          return 0;
+
+        case VNET_API_ERROR_INVALID_DST_ADDRESS:
+          return clib_error_return (0, "Invalid server address");
+          
+        case VNET_API_ERROR_INVALID_SRC_ADDRESS:
+          return clib_error_return (0, "Invalid src address");
+          
+        case VNET_API_ERROR_NO_SUCH_INNER_FIB:
+          return clib_error_return (0, "No such rx fib id %d", rx_fib_id);
+          
+        case VNET_API_ERROR_NO_SUCH_FIB:
+          return clib_error_return (0, "No such server fib id %d", 
+                                    server_fib_id);
+
+        case VNET_API_ERROR_NO_SUCH_ENTRY:
+          return clib_error_return 
+            (0, "Fib id %d: no per-fib DHCP server configured", rx_fib_id);
+
+        default:
+          return clib_error_return (0, "BUG: rv %d", rv);
+        }
+    }
+  else
+    return clib_error_return (0, "parse error`%U'",
+                              format_unformat_error, input);
+}
+
+VLIB_CLI_COMMAND (dhcp_proxy_set_command, static) = {
+  .path = "set dhcp proxy",
+  .short_help = "set dhcp proxy [del] server <ip-addr> src-address <ip-addr> [add-option-82] [server-fib-id <n>] [rx-fib-id <n>]",
+  .function = dhcp_proxy_set_command_fn,
+};
+
+u8 * format_dhcp_proxy_server (u8 * s, va_list * args)
+{
+  dhcp_proxy_main_t * dm = va_arg (*args, dhcp_proxy_main_t *);
+  dhcp_server_t * server = va_arg (*args, dhcp_server_t *);
+  u32 rx_fib_index = va_arg (*args, u32);
+  ip4_fib_t * rx_fib, * server_fib;
+  u32 server_fib_id = ~0, rx_fib_id = ~0;
+
+  if (dm == 0)
+    {
+      s = format (s, "%=16s%=16s%=14s%=14s%=20s", "Server", "Src Address", 
+                  "Server FIB", "RX FIB", "Insert Option 82");
+      return s;
+    }
+
+  server_fib = ip4_fib_get(server->server_fib_index);
+
+  if (server_fib)
+    server_fib_id = server_fib->table_id;
+
+  rx_fib = ip4_fib_get(rx_fib_index);
+
+  if (rx_fib)
+    rx_fib_id = rx_fib->table_id;
+
+  s = format (s, "%=16U%=16U%=14u%=14u%=20s",
+              format_ip4_address, &server->dhcp_server,
+              format_ip4_address, &server->dhcp_src_address,
+              server_fib_id, rx_fib_id,
+              server->insert_option_82 ? "yes" : "no");
+  return s;
+}
+
+static clib_error_t *
+dhcp_proxy_show_command_fn (vlib_main_t * vm,
+                            unformat_input_t * input,
+                            vlib_cli_command_t * cmd)
+{
+  dhcp_proxy_main_t * dpm = &dhcp_proxy_main;
+  ip4_main_t * im = &ip4_main;
+  dhcp_server_t * server;
+  u32 server_index;
+  int i;
+
+  vlib_cli_output (vm, "%U", format_dhcp_proxy_server, 0 /* header line */,
+                   0, 0);
+
+  for (i = 0; i < vec_len (im->fibs); i++)
+    {
+      if (i < vec_len(dpm->dhcp_server_index_by_rx_fib_index))
+        server_index = dpm->dhcp_server_index_by_rx_fib_index[i];
+      else
+        server_index = 0;
+      server = pool_elt_at_index (dpm->dhcp_servers, server_index);
+      if (server->valid)
+        vlib_cli_output (vm, "%U", format_dhcp_proxy_server, dpm, 
+                         server, i);
+    }
+
+  return 0;
+}
+
+VLIB_CLI_COMMAND (dhcp_proxy_show_command, static) = {
+  .path = "show dhcp proxy",
+  .short_help = "Display dhcp proxy server info",
+  .function = dhcp_proxy_show_command_fn,
+};
+
+
+int dhcp_proxy_set_option82_vss(  u32 vrf_id,
+                                  u32 oui,
+                                  u32 fib_id, 
+                                  int is_del)
+{
+  dhcp_proxy_main_t *dm = &dhcp_proxy_main;
+  uword *p;
+  vss_info *a;
+  u32 old_oui=0, old_fib_id=0;
+  
+  p = hash_get (dm->opt82vss_index_by_vrf_id, vrf_id);
+
+  if (p) 
+    {
+      a = pool_elt_at_index (dm->opt82vss, p[0]);
+      if (!a) 
+        return VNET_API_ERROR_NO_SUCH_FIB;
+      old_oui = a->vpn_id.oui;
+      old_fib_id = a->vpn_id.fib_id;
+          
+      if (is_del)
+        {
+          if (old_oui == oui &&
+              old_fib_id == fib_id)
+            {
+              pool_put(dm->opt82vss, a);
+              hash_unset (dm->opt82vss_index_by_vrf_id, vrf_id);
+              return 0;
+            }
+          else
+            return VNET_API_ERROR_NO_SUCH_ENTRY;
+        }
+      pool_put(dm->opt82vss, a);
+      hash_unset (dm->opt82vss_index_by_vrf_id, vrf_id);
+  } else if (is_del)
+    return VNET_API_ERROR_NO_SUCH_ENTRY;
+  pool_get (dm->opt82vss, a);
+  memset (a, ~0, sizeof (a[0]));
+  a->vpn_id.oui = oui;
+  a->vpn_id.fib_id = fib_id;
+  hash_set (dm->opt82vss_index_by_vrf_id, vrf_id, a - dm->opt82vss);
+  
+  return 0;
+}
+
+static clib_error_t *
+dhcp_option_82_vss_fn (vlib_main_t * vm,
+                        unformat_input_t * input,
+                        vlib_cli_command_t * cmd)
+{
+  int is_del = 0, got_new_vpn_id=0;
+  u32 oui=0, fib_id=0, tbl_id=~0;
+ 
+
+  while (unformat_check_input(input) != UNFORMAT_END_OF_INPUT) 
+    {
+
+      if (unformat(input, "delete") || unformat(input, "del"))
+          is_del = 1;    
+      else if (unformat (input, "oui %d", &oui))
+          got_new_vpn_id = 1;
+      else if (unformat (input, "vpn-id %d", &fib_id))
+          got_new_vpn_id = 1;
+      else if (unformat (input, "table %d", &tbl_id))
+          got_new_vpn_id = 1;
+      else
+          break;
+  }
+  if (tbl_id == ~0)
+      return clib_error_return (0, "no table ID specified.");
+  
+  if (is_del || got_new_vpn_id)
+    {
+      int rv;
+      rv = dhcp_proxy_set_option82_vss(tbl_id, oui, fib_id, is_del);
+      switch (rv)
+        {
+        case 0:
+            return 0;
+            
+        case VNET_API_ERROR_NO_SUCH_FIB:
+            return clib_error_return (0, "option 82 vss(oui:%d, vpn-id:%d) not found in table %d",
+                                      oui, fib_id, tbl_id);
+            
+        case VNET_API_ERROR_NO_SUCH_ENTRY:
+            return clib_error_return (0, "option 82 vss for table %d not found in in pool.",
+                                      tbl_id);
+        default:
+          return clib_error_return (0, "BUG: rv %d", rv);
+        }
+    }
+  else
+      return clib_error_return (0, "parse error`%U'",
+                                format_unformat_error, input);
+}
+
+VLIB_CLI_COMMAND (dhcp_proxy_vss_command,static) = {
+  .path = "set dhcp option-82 vss",
+  .short_help = "set dhcp option-82 vss [del] table <table id> oui <oui> vpn-id <vpn-id>",
+  .function = dhcp_option_82_vss_fn,
+};
+
+
+static clib_error_t *
+dhcp_vss_show_command_fn (vlib_main_t * vm,
+                          unformat_input_t * input,
+                          vlib_cli_command_t * cmd)
+  
+{
+  dhcp_proxy_main_t * dm = &dhcp_proxy_main;
+  vss_info *v;
+  u32 oui;
+  u32 fib_id;
+  u32 tbl_id;
+  uword index;
+  
+  vlib_cli_output (vm, "%=9s%=11s%=12s","Table", "OUI", "VPN-ID");
+  hash_foreach (tbl_id, index, dm->opt82vss_index_by_vrf_id,
+  ({
+     v = pool_elt_at_index (dm->opt82vss, index);
+     oui = v->vpn_id.oui;
+     fib_id = v->vpn_id.fib_id;
+     vlib_cli_output (vm, "%=9d 0x%08x%=12d",
+                      tbl_id, oui, fib_id);
+  }));
+  
+  return 0;
+}
+
+VLIB_CLI_COMMAND (dhcp_proxy_vss_show_command, static) = {
+  .path = "show dhcp vss",
+  .short_help = "show dhcp VSS",
+  .function = dhcp_vss_show_command_fn,
+};
+
+static clib_error_t *
+dhcp_option_82_address_show_command_fn (vlib_main_t * vm,
+                                unformat_input_t * input,
+                                vlib_cli_command_t * cmd)
+  
+{
+  dhcp_proxy_main_t *dm = &dhcp_proxy_main;
+  vnet_main_t *vnm = vnet_get_main();                                     
+  u32 sw_if_index0=0, sw_if_index;
+  ip4_address_t *ia0;
+  vnet_sw_interface_t *swif;
+  
+  while (unformat_check_input(input) != UNFORMAT_END_OF_INPUT) 
+    {
+      
+      if (unformat(input, "%U",
+                   unformat_vnet_sw_interface, dm->vnet_main, &sw_if_index0))
+        {
+          swif = vnet_get_sw_interface (vnm, sw_if_index0);
+          sw_if_index = (swif->flags & VNET_SW_INTERFACE_FLAG_UNNUMBERED) ?
+            swif->unnumbered_sw_if_index : sw_if_index0;
+          ia0 = ip4_interface_first_address(&ip4_main, sw_if_index, 0);
+          if (ia0)
+            {
+              vlib_cli_output (vm, "%=20s%=20s", "interface", 
+                               "source IP address");
+              
+              vlib_cli_output (vm, "%=20U%=20U",
+                               format_vnet_sw_if_index_name, 
+                               dm->vnet_main, sw_if_index0,
+                               format_ip4_address, ia0);
+            }
+          else
+            vlib_cli_output (vm, "%=34s %=20U", 
+                             "No IPv4 address configured on",
+                             format_vnet_sw_if_index_name, 
+                             dm->vnet_main, sw_if_index);
+        }
+      else
+        break;
+    }
+  
+  return 0;
+}
+
+VLIB_CLI_COMMAND (dhcp_proxy_address_show_command,static) = {
+  .path = "show dhcp option-82-address interface",
+  .short_help = "show dhcp option-82-address interface <interface>",
+  .function = dhcp_option_82_address_show_command_fn,
+};