dhcp: fix unicast pkts, clean up state machine

Nominally a bug-fix cherry-pick, but completely manual. Closer to a
full feature backport minus binary api changes.

Send dhcp unicast packets to ip4-lookup. Otherwise, these packets
won't reach a dhcp server on a different subnet.

Do an immediate client scan after processing wakeup events.

Calculate the next process wakeup time by scanning all
clients.

Increase maximum (idle, no-clients-configured) timeout to 1000
seconds.

Reduce log spew.

Type: fix

Signed-off-by: Dave Barach <dave@barachs.net>
Change-Id: I3d10cd4c353298ed0b19e7e30887dc1d8d07b19e
(cherry picked from commit c54162981cdd41d65ed283df36955007552ddffe)

src/vlibmemory/api.h

@@ -26,6 +26,7 @@
 #include <vlibmemory/socket_client.h>
 
 void vl_api_rpc_call_main_thread (void *fp, u8 * data, u32 data_length);
+void vl_api_force_rpc_call_main_thread (void *fp, u8 * data, u32 data_length);
 u16 vl_client_get_first_plugin_msg_id (const char *plugin_name);
 void vl_api_send_pending_rpc_requests (vlib_main_t * vm);
 u8 *vl_api_serialize_message_table (api_main_t * am, u8 * vector);

src/vnet/CMakeLists.txt

@@ -890,6 +890,7 @@ list(APPEND VNET_API_FILES lisp-gpe/lisp_gpe.api)
 ##############################################################################
 list(APPEND VNET_SOURCES
   dhcp/client.c
+  dhcp/dhcp4_packet.c
   dhcp/dhcp_client_detect.c
   dhcp/dhcp6_client_common_dp.c
   dhcp/dhcp6_pd_client_dp.c

src/vnet/dhcp/client.h

@@ -42,6 +42,24 @@ struct dhcp_client_t_;
 typedef void (*dhcp_event_cb_t) (u32 client_index,
 				 const struct dhcp_client_t_ * client);
 
+/**
+ * The set of addresses/mask that contribute forwarding info
+ * and are installed.
+ */
+typedef struct dhcp_client_fwd_addresses_t_
+{
+  /** the address assigned to this client and it's mask */
+  ip4_address_t leased_address;
+  u32 subnet_mask_width;
+
+  /** the address of the DHCP server handing out the address.
+      this is used to send any unicast messages */
+  ip4_address_t dhcp_server;
+
+  /** The address of this client's default gateway - may not be present */
+  ip4_address_t router_address;
+} dhcp_client_fwd_addresses_t;
+
 typedef struct dhcp_client_t_
 {
   dhcp_client_state_t state;
@@ -59,11 +77,16 @@ typedef struct dhcp_client_t_
   /* 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 */
+  /**
+   * leased address, other learned info DHCP
+   *  the learned set is updated by new messages recieved in the DP
+   *  the installed set is what's actually been added
+   */
+  dhcp_client_fwd_addresses_t learned;
+  dhcp_client_fwd_addresses_t installed;
+  /* have local Addresses and default route been installed */
+  u8 addresses_installed;
+
   ip4_address_t *domain_server_address;	/* option 6 */
   u32 lease_renewal_interval;	/* option 51 */
   u32 lease_lifetime;		/* option 59 */
@@ -85,8 +108,6 @@ typedef struct dhcp_client_t_
   u8 client_hardware_address[6];
   u8 client_detect_feature_enabled;
 
-  /* the unicast adjacency for the DHCP server */
-  adj_index_t ai_ucast;
   /* the broadcast adjacency on the link */
   adj_index_t ai_bcast;
   /* IP DSCP to set in sent packets */
@@ -102,6 +123,9 @@ typedef struct
   uword *client_by_sw_if_index;
   u32 seed;
 
+  /* ip4-lookup node index */
+  u32 ip4_lookup_node_index;
+
   /* convenience */
   vlib_main_t *vlib_main;
   vnet_main_t *vnet_main;

src/vnet/dhcp/dhcp4_packet.c

@@ -0,0 +1,122 @@
+/*
+ * dhcp4_packet.c: dhcp packet format functions
+ *
+ * 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/dhcp/dhcp4_packet.h>
+#include <vnet/ip/format.h>
+
+u8 *
+format_dhcp_packet_type (u8 * s, va_list * args)
+{
+  dhcp_packet_type_t pt = va_arg (*args, dhcp_packet_type_t);
+
+  switch (pt)
+    {
+    case DHCP_PACKET_DISCOVER:
+      s = format (s, "discover");
+      break;
+    case DHCP_PACKET_OFFER:
+      s = format (s, "offer");
+      break;
+    case DHCP_PACKET_REQUEST:
+      s = format (s, "request");
+      break;
+    case DHCP_PACKET_ACK:
+      s = format (s, "ack");
+      break;
+    case DHCP_PACKET_NAK:
+      s = format (s, "nack");
+      break;
+    }
+  return (s);
+}
+
+u8 *
+format_dhcp_header (u8 * s, va_list * args)
+{
+  dhcp_header_t *d = va_arg (*args, dhcp_header_t *);
+  u32 max_bytes = va_arg (*args, u32);
+  dhcp_option_t *o;
+  u32 tmp;
+
+  s = format (s, "opcode:%s", (d->opcode == 1 ? "request" : "reply"));
+  s = format (s, " hw[type:%d addr-len:%d addr:%U]",
+	      d->hardware_type, d->hardware_address_length,
+	      format_hex_bytes, d->client_hardware_address,
+	      d->hardware_address_length);
+  s = format (s, " hops%d", d->hops);
+  s = format (s, " transaction-ID:0x%x", d->transaction_identifier);
+  s = format (s, " seconds:%d", d->seconds);
+  s = format (s, " flags:0x%x", d->flags);
+  s = format (s, " client:%U", format_ip4_address, &d->client_ip_address);
+  s = format (s, " your:%U", format_ip4_address, &d->your_ip_address);
+  s = format (s, " server:%U", format_ip4_address, &d->server_ip_address);
+  s = format (s, " gateway:%U", format_ip4_address, &d->gateway_ip_address);
+  s = format (s, " cookie:%U", format_ip4_address, &d->magic_cookie);
+
+  o = (dhcp_option_t *) d->options;
+
+  while (o->option != 0xFF /* end of options */  &&
+	 (u8 *) o < (u8 *) d + max_bytes)
+    {
+      switch (o->option)
+	{
+	case 53:		/* dhcp message type */
+	  tmp = o->data[0];
+	  s =
+	    format (s, ", option-53: type:%U", format_dhcp_packet_type, tmp);
+	  break;
+	case 54:		/* dhcp server address */
+	  s = format (s, ", option-54: server:%U",
+		      format_ip4_address, &o->data_as_u32[0]);
+	  break;
+	case 58:		/* lease renew time in seconds */
+	  s = format (s, ", option-58: renewal:%d",
+		      clib_host_to_net_u32 (o->data_as_u32[0]));
+	  break;
+	case 1:		/* subnet mask */
+	  s = format (s, ", option-1: subnet-mask:%d",
+		      clib_host_to_net_u32 (o->data_as_u32[0]));
+	  break;
+	case 3:		/* router address */
+	  s = format (s, ", option-3: router:%U",
+		      format_ip4_address, &o->data_as_u32[0]);
+	  break;
+	case 6:		/* domain server address */
+	  s = format (s, ", option-6: domian-server:%U",
+		      format_hex_bytes, o->data, o->length);
+	  break;
+	case 12:		/* hostname */
+	  s = format (s, ", option-12: hostname:%U",
+		      format_hex_bytes, o->data, o->length);
+	  break;
+	default:
+	  tmp = o->option;
+	  s = format (s, " option-%d: skipped", tmp);
+	  break;
+	}
+      o = (dhcp_option_t *) (((u8 *) o) + (o->length + 2));
+    }
+  return (s);
+}
+
+/*
+ * fd.io coding-style-patch-verification: ON
+ *
+ * Local Variables:
+ * eval: (c-set-style "gnu")
+ * End:
+ */

src/vnet/dhcp/dhcp4_packet.h

@@ -51,6 +51,8 @@ typedef struct
   dhcp_option_t options[0];
 } dhcp_header_t;
 
+extern u8 *format_dhcp_header (u8 * s, va_list * args);
+
 typedef enum
 {
   DHCP_PACKET_DISCOVER = 1,
@@ -60,6 +62,8 @@ typedef enum
   DHCP_PACKET_NAK,
 } dhcp_packet_type_t;
 
+extern u8 *format_dhcp_packet_type (u8 * s, va_list * args);
+
 typedef enum dhcp_packet_option_t_
 {
   DHCP_PACKET_OPTION_MSG_TYPE = 53,

src/vnet/dhcp/dhcp_api.c

@@ -228,10 +228,12 @@ dhcp_client_lease_encode (vl_api_dhcp_lease_t * lease,
   clib_memcpy (&lease->hostname, client->hostname, len);
   lease->hostname[len] = 0;
 
-  lease->mask_width = client->subnet_mask_width;
-  clib_memcpy (&lease->host_address[0], (u8 *) & client->leased_address,
+  lease->mask_width = client->installed.subnet_mask_width;
+  clib_memcpy (&lease->host_address[0],
+	       (u8 *) & client->installed.leased_address,
 	       sizeof (ip4_address_t));
-  clib_memcpy (&lease->router_address[0], (u8 *) & client->router_address,
+  clib_memcpy (&lease->router_address[0],
+	       (u8 *) & client->installed.router_address,
 	       sizeof (ip4_address_t));
 
   lease->count = vec_len (client->domain_server_address);

test/test_dhcp.py

@@ -242,6 +242,7 @@ class TestDHCP(VppTestCase):
         self.verify_dhcp_msg_type(pkt, "discover")
         self.verify_dhcp_has_option(pkt, "hostname", hostname)
         if client_id:
+            client_id = '\x00' + client_id
             self.verify_dhcp_has_option(pkt, "client_id", client_id)
         bootp = pkt[BOOTP]
         self.assertEqual(bootp.ciaddr, "0.0.0.0")