Reorganize source tree to use single autotools instance

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

1 files changed, 639 insertions, 0 deletions

diff --git a/src/vnet/bfd/bfd_udp.c b/src/vnet/bfd/bfd_udp.c
new file mode 100644
index 00000000000..3c747d86a10
--- /dev/null
+++ b/src/vnet/bfd/bfd_udp.c
@@ -0,0 +1,639 @@
+#include <vppinfra/types.h>
+#include <vlibmemory/api.h>
+#include <vlib/vlib.h>
+#include <vlib/buffer.h>
+#include <vnet/ip/format.h>
+#include <vnet/ethernet/packet.h>
+#include <vnet/ip/udp_packet.h>
+#include <vnet/ip/lookup.h>
+#include <vnet/ip/icmp46_packet.h>
+#include <vnet/ip/ip4.h>
+#include <vnet/ip/ip6.h>
+#include <vnet/ip/udp.h>
+#include <vnet/ip/ip6_packet.h>
+#include <vnet/adj/adj.h>
+#include <vnet/adj/adj_nbr.h>
+#include <vnet/bfd/bfd_debug.h>
+#include <vnet/bfd/bfd_udp.h>
+#include <vnet/bfd/bfd_main.h>
+#include <vnet/bfd/bfd_api.h>
+
+typedef struct
+{
+  bfd_main_t *bfd_main;
+  /* hashmap - bfd session index by bfd key - used for CLI/API lookup, where
+   * discriminator is unknown */
+  mhash_t bfd_session_idx_by_bfd_key;
+} bfd_udp_main_t;
+
+static vlib_node_registration_t bfd_udp4_input_node;
+static vlib_node_registration_t bfd_udp6_input_node;
+
+bfd_udp_main_t bfd_udp_main;
+
+void bfd_udp_transport_to_buffer (vlib_main_t *vm, vlib_buffer_t *b,
+                                  bfd_udp_session_t *bus)
+{
+  udp_header_t *udp;
+  u16 udp_length, ip_length;
+  bfd_udp_key_t *key = &bus->key;
+
+  b->flags |= VNET_BUFFER_LOCALLY_ORIGINATED;
+  if (ip46_address_is_ip4 (&key->local_addr))
+    {
+      ip4_header_t *ip4;
+      const size_t data_size = sizeof (*ip4) + sizeof (*udp);
+      vlib_buffer_advance (b, -data_size);
+      ip4 = vlib_buffer_get_current (b);
+      udp = (udp_header_t *)(ip4 + 1);
+      memset (ip4, 0, data_size);
+      ip4->ip_version_and_header_length = 0x45;
+      ip4->ttl = 255;
+      ip4->protocol = IP_PROTOCOL_UDP;
+      ip4->src_address.as_u32 = key->local_addr.ip4.as_u32;
+      ip4->dst_address.as_u32 = key->peer_addr.ip4.as_u32;
+
+      udp->src_port = clib_host_to_net_u16 (50000); /* FIXME */
+      udp->dst_port = clib_host_to_net_u16 (UDP_DST_PORT_bfd4);
+
+      /* fix ip length, checksum and udp length */
+      ip_length = vlib_buffer_length_in_chain (vm, b);
+
+      ip4->length = clib_host_to_net_u16 (ip_length);
+      ip4->checksum = ip4_header_checksum (ip4);
+
+      udp_length = ip_length - (sizeof (*ip4));
+      udp->length = clib_host_to_net_u16 (udp_length);
+    }
+  else
+    {
+      BFD_ERR ("not implemented");
+      abort ();
+    }
+}
+
+void bfd_add_udp_transport (vlib_main_t *vm, vlib_buffer_t *b,
+                            bfd_udp_session_t *bus)
+{
+  vnet_buffer (b)->ip.adj_index[VLIB_RX] = bus->adj_index;
+  vnet_buffer (b)->ip.adj_index[VLIB_TX] = bus->adj_index;
+  bfd_udp_transport_to_buffer (vm, b, bus);
+}
+
+static bfd_session_t *bfd_lookup_session (bfd_udp_main_t *bum,
+                                          const bfd_udp_key_t *key)
+{
+  uword *p = mhash_get (&bum->bfd_session_idx_by_bfd_key, key);
+  if (p)
+    {
+      return bfd_find_session_by_idx (bum->bfd_main, *p);
+    }
+  return 0;
+}
+
+static vnet_api_error_t
+bfd_udp_add_session_internal (bfd_udp_main_t *bum, u32 sw_if_index,
+                              u32 desired_min_tx_us, u32 required_min_rx_us,
+                              u8 detect_mult, const ip46_address_t *local_addr,
+                              const ip46_address_t *peer_addr)
+{
+  vnet_sw_interface_t *sw_if =
+      vnet_get_sw_interface (vnet_get_main (), sw_if_index);
+  /* get a pool entry and if we end up not needing it, give it back */
+  bfd_transport_t t = BFD_TRANSPORT_UDP4;
+  if (!ip46_address_is_ip4 (local_addr))
+    {
+      t = BFD_TRANSPORT_UDP6;
+    }
+  bfd_session_t *bs = bfd_get_session (bum->bfd_main, t);
+  bfd_udp_session_t *bus = &bs->udp;
+  memset (bus, 0, sizeof (*bus));
+  bfd_udp_key_t *key = &bus->key;
+  key->sw_if_index = sw_if->sw_if_index;
+  key->local_addr.as_u64[0] = local_addr->as_u64[0];
+  key->local_addr.as_u64[1] = local_addr->as_u64[1];
+  key->peer_addr.as_u64[0] = peer_addr->as_u64[0];
+  key->peer_addr.as_u64[1] = peer_addr->as_u64[1];
+  const bfd_session_t *tmp = bfd_lookup_session (bum, key);
+  if (tmp)
+    {
+      BFD_ERR ("duplicate bfd-udp session, existing bs_idx=%d", tmp->bs_idx);
+      bfd_put_session (bum->bfd_main, bs);
+      return VNET_API_ERROR_BFD_EEXIST;
+    }
+  key->sw_if_index = sw_if->sw_if_index;
+  mhash_set (&bum->bfd_session_idx_by_bfd_key, key, bs->bs_idx, NULL);
+  BFD_DBG ("session created, bs_idx=%u, sw_if_index=%d, local=%U, peer=%U",
+           bs->bs_idx, key->sw_if_index, format_ip46_address, &key->local_addr,
+           IP46_TYPE_ANY, format_ip46_address, &key->peer_addr, IP46_TYPE_ANY);
+  if (BFD_TRANSPORT_UDP4 == t)
+    {
+      bus->adj_index = adj_nbr_add_or_lock (FIB_PROTOCOL_IP4, VNET_LINK_IP4,
+                                            &key->peer_addr, key->sw_if_index);
+      BFD_DBG ("adj_nbr_add_or_lock(FIB_PROTOCOL_IP4, VNET_LINK_IP4, %U, %d) "
+               "returns %d",
+               format_ip46_address, &key->peer_addr, IP46_TYPE_ANY,
+               key->sw_if_index, bus->adj_index);
+    }
+  else
+    {
+      bus->adj_index = adj_nbr_add_or_lock (FIB_PROTOCOL_IP6, VNET_LINK_IP6,
+                                            &key->peer_addr, key->sw_if_index);
+      BFD_DBG ("adj_nbr_add_or_lock(FIB_PROTOCOL_IP6, VNET_LINK_IP6, %U, %d) "
+               "returns %d",
+               format_ip46_address, &key->peer_addr, IP46_TYPE_ANY,
+               key->sw_if_index, bus->adj_index);
+    }
+  bs->config_desired_min_tx_us = desired_min_tx_us;
+  bs->required_min_rx_us = required_min_rx_us;
+  bs->local_detect_mult = detect_mult;
+  bfd_session_start (bum->bfd_main, bs);
+  return 0;
+}
+
+static vnet_api_error_t
+bfd_udp_validate_api_input (u32 sw_if_index, const ip46_address_t *local_addr,
+                            const ip46_address_t *peer_addr)
+{
+  vnet_sw_interface_t *sw_if =
+      vnet_get_sw_interface (vnet_get_main (), sw_if_index);
+  u8 local_ip_valid = 0;
+  ip_interface_address_t *ia = NULL;
+  if (!sw_if)
+    {
+      BFD_ERR ("got NULL sw_if");
+      return VNET_API_ERROR_INVALID_SW_IF_INDEX;
+    }
+  if (ip46_address_is_ip4 (local_addr))
+    {
+      if (!ip46_address_is_ip4 (peer_addr))
+        {
+          BFD_ERR ("IP family mismatch");
+          return VNET_API_ERROR_INVALID_ARGUMENT;
+        }
+      ip4_main_t *im = &ip4_main;
+
+      /* *INDENT-OFF* */
+      foreach_ip_interface_address (
+          &im->lookup_main, ia, sw_if_index, 0 /* honor unnumbered */, ({
+            ip4_address_t *x =
+                ip_interface_address_get_address (&im->lookup_main, ia);
+            if (x->as_u32 == local_addr->ip4.as_u32)
+              {
+                /* valid address for this interface */
+                local_ip_valid = 1;
+                break;
+              }
+          }));
+      /* *INDENT-ON* */
+    }
+  else
+    {
+      if (ip46_address_is_ip4 (peer_addr))
+        {
+          BFD_ERR ("IP family mismatch");
+          return VNET_API_ERROR_INVALID_ARGUMENT;
+        }
+      ip6_main_t *im = &ip6_main;
+      /* *INDENT-OFF* */
+      foreach_ip_interface_address (
+          &im->lookup_main, ia, sw_if_index, 0 /* honor unnumbered */, ({
+            ip6_address_t *x =
+                ip_interface_address_get_address (&im->lookup_main, ia);
+            if (local_addr->ip6.as_u64[0] == x->as_u64[0] &&
+                local_addr->ip6.as_u64[1] == x->as_u64[1])
+              {
+                /* valid address for this interface */
+                local_ip_valid = 1;
+                break;
+              }
+          }));
+      /* *INDENT-ON* */
+    }
+
+  if (!local_ip_valid)
+    {
+      BFD_ERR ("address not found on interface");
+      return VNET_API_ERROR_ADDRESS_NOT_FOUND_FOR_INTERFACE;
+    }
+
+  return 0;
+}
+
+vnet_api_error_t bfd_udp_add_session (u32 sw_if_index, u32 desired_min_tx_us,
+                                      u32 required_min_rx_us, u8 detect_mult,
+                                      const ip46_address_t *local_addr,
+                                      const ip46_address_t *peer_addr)
+{
+  vnet_api_error_t rv =
+      bfd_udp_validate_api_input (sw_if_index, local_addr, peer_addr);
+  if (rv)
+    {
+      return rv;
+    }
+  if (detect_mult < 1)
+    {
+      BFD_ERR ("detect_mult < 1");
+      return VNET_API_ERROR_INVALID_ARGUMENT;
+    }
+  if (desired_min_tx_us < 1)
+    {
+      BFD_ERR ("desired_min_tx_us < 1");
+      return VNET_API_ERROR_INVALID_ARGUMENT;
+    }
+  return bfd_udp_add_session_internal (&bfd_udp_main, sw_if_index,
+                                       desired_min_tx_us, required_min_rx_us,
+                                       detect_mult, local_addr, peer_addr);
+}
+
+vnet_api_error_t bfd_udp_del_session (u32 sw_if_index,
+                                      const ip46_address_t *local_addr,
+                                      const ip46_address_t *peer_addr)
+{
+  vnet_api_error_t rv =
+      bfd_udp_validate_api_input (sw_if_index, local_addr, peer_addr);
+  if (rv)
+    {
+      return rv;
+    }
+  bfd_udp_main_t *bum = &bfd_udp_main;
+  vnet_sw_interface_t *sw_if =
+      vnet_get_sw_interface (vnet_get_main (), sw_if_index);
+  bfd_udp_key_t key;
+  memset (&key, 0, sizeof (key));
+  key.sw_if_index = sw_if->sw_if_index;
+  key.local_addr.as_u64[0] = local_addr->as_u64[0];
+  key.local_addr.as_u64[1] = local_addr->as_u64[1];
+  key.peer_addr.as_u64[0] = peer_addr->as_u64[0];
+  key.peer_addr.as_u64[1] = peer_addr->as_u64[1];
+  bfd_session_t *tmp = bfd_lookup_session (bum, &key);
+  if (tmp)
+    {
+      BFD_DBG ("free bfd-udp session, bs_idx=%d", tmp->bs_idx);
+      mhash_unset (&bum->bfd_session_idx_by_bfd_key, &key, NULL);
+      adj_unlock (tmp->udp.adj_index);
+      bfd_put_session (bum->bfd_main, tmp);
+    }
+  else
+    {
+      BFD_ERR ("no such session");
+      return VNET_API_ERROR_BFD_NOENT;
+    }
+  return 0;
+}
+
+typedef enum {
+  BFD_UDP_INPUT_NEXT_NORMAL,
+  BFD_UDP_INPUT_NEXT_REPLY,
+  BFD_UDP_INPUT_N_NEXT,
+} bfd_udp_input_next_t;
+
+/* Packet counters */
+#define foreach_bfd_udp_error(F)           \
+  F (NONE, "good bfd packets (processed)") \
+  F (BAD, "invalid bfd packets")           \
+  F (DISABLED, "bfd packets received on disabled interfaces")
+
+#define F(sym, string) static char BFD_UDP_ERR_##sym##_STR[] = string;
+foreach_bfd_udp_error (F);
+#undef F
+
+static char *bfd_udp_error_strings[] = {
+#define F(sym, string) BFD_UDP_ERR_##sym##_STR,
+  foreach_bfd_udp_error (F)
+#undef F
+};
+
+typedef enum {
+#define F(sym, str) BFD_UDP_ERROR_##sym,
+  foreach_bfd_udp_error (F)
+#undef F
+      BFD_UDP_N_ERROR,
+} bfd_udp_error_t;
+
+static void bfd_udp4_find_headers (vlib_buffer_t *b, const ip4_header_t **ip4,
+                                   const udp_header_t **udp)
+{
+  /* sanity check first */
+  const i32 start = vnet_buffer (b)->ip.start_of_ip_header;
+  if (start < 0 && start < sizeof (b->pre_data))
+    {
+      BFD_ERR ("Start of ip header is before pre_data, ignoring");
+      *ip4 = NULL;
+      *udp = NULL;
+      return;
+    }
+  *ip4 = (ip4_header_t *)(b->data + start);
+  if ((u8 *)*ip4 > (u8 *)vlib_buffer_get_current (b))
+    {
+      BFD_ERR ("Start of ip header is beyond current data, ignoring");
+      *ip4 = NULL;
+      *udp = NULL;
+      return;
+    }
+  *udp = (udp_header_t *)((*ip4) + 1);
+}
+
+static bfd_udp_error_t bfd_udp4_verify_transport (const ip4_header_t *ip4,
+                                                  const udp_header_t *udp,
+                                                  const bfd_session_t *bs)
+{
+  const bfd_udp_session_t *bus = &bs->udp;
+  const bfd_udp_key_t *key = &bus->key;
+  if (ip4->src_address.as_u32 != key->peer_addr.ip4.as_u32)
+    {
+      BFD_ERR ("IP src addr mismatch, got %U, expected %U", format_ip4_address,
+               ip4->src_address.as_u32, format_ip4_address,
+               key->peer_addr.ip4.as_u32);
+      return BFD_UDP_ERROR_BAD;
+    }
+  if (ip4->dst_address.as_u32 != key->local_addr.ip4.as_u32)
+    {
+      BFD_ERR ("IP dst addr mismatch, got %U, expected %U", format_ip4_address,
+               ip4->dst_address.as_u32, format_ip4_address,
+               key->local_addr.ip4.as_u32);
+      return BFD_UDP_ERROR_BAD;
+    }
+  const u8 expected_ttl = 255;
+  if (ip4->ttl != expected_ttl)
+    {
+      BFD_ERR ("IP unexpected TTL value %d, expected %d", ip4->ttl,
+               expected_ttl);
+      return BFD_UDP_ERROR_BAD;
+    }
+  if (clib_net_to_host_u16 (udp->src_port) < 49152 ||
+      clib_net_to_host_u16 (udp->src_port) > 65535)
+    {
+      BFD_ERR ("Invalid UDP src port %d, out of range <49152,65535>",
+               udp->src_port);
+    }
+  return BFD_UDP_ERROR_NONE;
+}
+
+typedef struct
+{
+  u32 bs_idx;
+  bfd_pkt_t pkt;
+} bfd_rpc_update_t;
+
+static void bfd_rpc_update_session_cb (const bfd_rpc_update_t *a)
+{
+  bfd_consume_pkt (bfd_udp_main.bfd_main, &a->pkt, a->bs_idx);
+}
+
+static void bfd_rpc_update_session (u32 bs_idx, const bfd_pkt_t *pkt)
+{
+  /* packet length was already verified to be correct by the caller */
+  const u32 data_size = sizeof (bfd_rpc_update_t) -
+                        STRUCT_SIZE_OF (bfd_rpc_update_t, pkt) +
+                        pkt->head.length;
+  u8 data[data_size];
+  bfd_rpc_update_t *update = (bfd_rpc_update_t *)data;
+  update->bs_idx = bs_idx;
+  clib_memcpy (&update->pkt, pkt, pkt->head.length);
+  vl_api_rpc_call_main_thread (bfd_rpc_update_session_cb, data, data_size);
+}
+
+static bfd_udp_error_t bfd_udp4_scan (vlib_main_t *vm, vlib_node_runtime_t *rt,
+                                      vlib_buffer_t *b, bfd_session_t **bs_out)
+{
+  const bfd_pkt_t *pkt = vlib_buffer_get_current (b);
+  if (sizeof (*pkt) > b->current_length)
+    {
+      BFD_ERR (
+          "Payload size %d too small to hold bfd packet of minimum size %d",
+          b->current_length, sizeof (*pkt));
+      return BFD_UDP_ERROR_BAD;
+    }
+  const ip4_header_t *ip4;
+  const udp_header_t *udp;
+  bfd_udp4_find_headers (b, &ip4, &udp);
+  if (!ip4 || !udp)
+    {
+      BFD_ERR ("Couldn't find ip4 or udp header");
+      return BFD_UDP_ERROR_BAD;
+    }
+  if (!bfd_verify_pkt_common (pkt))
+    {
+      return BFD_UDP_ERROR_BAD;
+    }
+  bfd_session_t *bs = NULL;
+  if (pkt->your_disc)
+    {
+      BFD_DBG ("Looking up BFD session using discriminator %u",
+               pkt->your_disc);
+      bs = bfd_find_session_by_disc (bfd_udp_main.bfd_main, pkt->your_disc);
+    }
+  else
+    {
+      bfd_udp_key_t key;
+      memset (&key, 0, sizeof (key));
+      key.sw_if_index = vnet_buffer (b)->sw_if_index[VLIB_RX];
+      key.local_addr.ip4.as_u32 = ip4->dst_address.as_u32;
+      key.peer_addr.ip4.as_u32 = ip4->src_address.as_u32;
+      BFD_DBG ("Looking up BFD session using key (sw_if_index=%u, local=%U, "
+               "peer=%U)",
+               key.sw_if_index, format_ip4_address, key.local_addr.ip4.as_u8,
+               format_ip4_address, key.peer_addr.ip4.as_u8);
+      bs = bfd_lookup_session (&bfd_udp_main, &key);
+    }
+  if (!bs)
+    {
+      BFD_ERR ("BFD session lookup failed - no session matches BFD pkt");
+      return BFD_UDP_ERROR_BAD;
+    }
+  BFD_DBG ("BFD session found, bs_idx=%u", bs->bs_idx);
+  if (!bfd_verify_pkt_session (pkt, b->current_length, bs))
+    {
+      return BFD_UDP_ERROR_BAD;
+    }
+  bfd_udp_error_t err;
+  if (BFD_UDP_ERROR_NONE != (err = bfd_udp4_verify_transport (ip4, udp, bs)))
+    {
+      return err;
+    }
+  bfd_rpc_update_session (bs->bs_idx, pkt);
+  *bs_out = bs;
+  return BFD_UDP_ERROR_NONE;
+}
+
+static bfd_udp_error_t bfd_udp6_scan (vlib_main_t *vm, vlib_buffer_t *b)
+{
+  /* TODO */
+  return BFD_UDP_ERROR_BAD;
+}
+
+/*
+ * Process a frame of bfd packets
+ * Expect 1 packet / frame
+ */
+static uword bfd_udp_input (vlib_main_t *vm, vlib_node_runtime_t *rt,
+                            vlib_frame_t *f, int is_ipv6)
+{
+  u32 n_left_from, *from;
+  bfd_input_trace_t *t0;
+
+  from = vlib_frame_vector_args (f); /* array of buffer indices */
+  n_left_from = f->n_vectors;        /* number of buffer indices */
+
+  while (n_left_from > 0)
+    {
+      u32 bi0;
+      vlib_buffer_t *b0;
+      u32 next0, error0;
+
+      bi0 = from[0];
+      b0 = vlib_get_buffer (vm, bi0);
+
+      bfd_session_t *bs = NULL;
+
+      /* If this pkt is traced, snapshot the data */
+      if (b0->flags & VLIB_BUFFER_IS_TRACED)
+        {
+          int len;
+          t0 = vlib_add_trace (vm, rt, b0, sizeof (*t0));
+          len = (b0->current_length < sizeof (t0->data)) ? b0->current_length
+                                                         : sizeof (t0->data);
+          t0->len = len;
+          clib_memcpy (t0->data, vlib_buffer_get_current (b0), len);
+        }
+
+      /* scan this bfd pkt. error0 is the counter index to bmp */
+      if (is_ipv6)
+        {
+          error0 = bfd_udp6_scan (vm, b0);
+        }
+      else
+        {
+          error0 = bfd_udp4_scan (vm, rt, b0, &bs);
+        }
+      b0->error = rt->errors[error0];
+
+      next0 = BFD_UDP_INPUT_NEXT_NORMAL;
+      if (BFD_UDP_ERROR_NONE == error0)
+        {
+          /* if everything went fine, check for poll bit, if present, re-use
+             the buffer and based on (now updated) session parameters, send the
+             final packet back */
+          const bfd_pkt_t *pkt = vlib_buffer_get_current (b0);
+          if (bfd_pkt_get_poll (pkt))
+            {
+              bfd_send_final (vm, b0, bs);
+              if (is_ipv6)
+                {
+                  vlib_node_increment_counter (vm, bfd_udp6_input_node.index,
+                                               b0->error, 1);
+                }
+              else
+                {
+                  vlib_node_increment_counter (vm, bfd_udp4_input_node.index,
+                                               b0->error, 1);
+                }
+              next0 = BFD_UDP_INPUT_NEXT_REPLY;
+            }
+        }
+      vlib_set_next_frame_buffer (vm, rt, next0, bi0);
+
+      from += 1;
+      n_left_from -= 1;
+    }
+
+  return f->n_vectors;
+}
+
+static uword bfd_udp4_input (vlib_main_t *vm, vlib_node_runtime_t *rt,
+                             vlib_frame_t *f)
+{
+  return bfd_udp_input (vm, rt, f, 0);
+}
+
+/*
+ * bfd input graph node declaration
+ */
+/* *INDENT-OFF* */
+VLIB_REGISTER_NODE (bfd_udp4_input_node, static) = {
+  .function = bfd_udp4_input,
+  .name = "bfd-udp4-input",
+  .vector_size = sizeof (u32),
+  .type = VLIB_NODE_TYPE_INTERNAL,
+
+  .n_errors = BFD_UDP_N_ERROR,
+  .error_strings = bfd_udp_error_strings,
+
+  .format_trace = bfd_input_format_trace,
+
+  .n_next_nodes = BFD_UDP_INPUT_N_NEXT,
+  .next_nodes =
+      {
+              [BFD_UDP_INPUT_NEXT_NORMAL] = "error-drop",
+              [BFD_UDP_INPUT_NEXT_REPLY] = "ip4-lookup",
+      },
+};
+/* *INDENT-ON* */
+
+static uword bfd_udp6_input (vlib_main_t *vm, vlib_node_runtime_t *rt,
+                             vlib_frame_t *f)
+{
+  return bfd_udp_input (vm, rt, f, 1);
+}
+
+/* *INDENT-OFF* */
+VLIB_REGISTER_NODE (bfd_udp6_input_node, static) = {
+  .function = bfd_udp6_input,
+  .name = "bfd-udp6-input",
+  .vector_size = sizeof (u32),
+  .type = VLIB_NODE_TYPE_INTERNAL,
+
+  .n_errors = BFD_UDP_N_ERROR,
+  .error_strings = bfd_udp_error_strings,
+
+  .format_trace = bfd_input_format_trace,
+
+  .n_next_nodes = BFD_UDP_INPUT_N_NEXT,
+  .next_nodes =
+      {
+              [BFD_UDP_INPUT_NEXT_NORMAL] = "error-drop",
+              [BFD_UDP_INPUT_NEXT_REPLY] = "ip6-lookup",
+      },
+};
+/* *INDENT-ON* */
+
+static clib_error_t *bfd_sw_interface_up_down (vnet_main_t *vnm,
+                                               u32 sw_if_index, u32 flags)
+{
+  // vnet_hw_interface_t *hi = vnet_get_sup_hw_interface (vnm, sw_if_index);
+  if (!(flags & VNET_SW_INTERFACE_FLAG_ADMIN_UP))
+    {
+      /* TODO */
+    }
+  return 0;
+}
+
+VNET_SW_INTERFACE_ADMIN_UP_DOWN_FUNCTION (bfd_sw_interface_up_down);
+
+static clib_error_t *bfd_hw_interface_up_down (vnet_main_t *vnm,
+                                               u32 hw_if_index, u32 flags)
+{
+  if (flags & VNET_HW_INTERFACE_FLAG_LINK_UP)
+    {
+      /* TODO */
+    }
+  return 0;
+}
+
+VNET_HW_INTERFACE_LINK_UP_DOWN_FUNCTION (bfd_hw_interface_up_down);
+
+/*
+ * setup function
+ */
+static clib_error_t *bfd_udp_init (vlib_main_t *vm)
+{
+  mhash_init (&bfd_udp_main.bfd_session_idx_by_bfd_key, sizeof (uword),
+              sizeof (bfd_udp_key_t));
+  bfd_udp_main.bfd_main = &bfd_main;
+  udp_register_dst_port (vm, UDP_DST_PORT_bfd4, bfd_udp4_input_node.index, 1);
+  udp_register_dst_port (vm, UDP_DST_PORT_bfd6, bfd_udp6_input_node.index, 0);
+  return 0;
+}
+
+VLIB_INIT_FUNCTION (bfd_udp_init);