text: /*
   * Copyright (c) 2016 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/mpls/mpls.h>
  #include <vnet/bier/bier_table.h>
  #include <vnet/bier/bier_entry.h>
  #include <vnet/bier/bier_fmask.h>
  #include <vnet/bier/bier_bit_string.h>
  #include <vnet/bier/bier_imp.h>
  #include <vnet/bier/bier_disp_table.h>
  #include <vnet/bier/bier_disp_entry.h>
  #include <vnet/fib/fib_entry.h>
  #include <vnet/fib/fib_table.h>
  #include <vnet/fib/mpls_fib.h>
  #include <vnet/dpo/load_balance.h>
  #include <vnet/dpo/drop_dpo.h>
  #include <vnet/dpo/lookup_dpo.h>
  #include <vnet/mfib/mfib_table.h>
  
  #include <vnet/fib/fib_test.h>
  
  /*
   * Add debugs for passing tests
   */
  static int bier_test_do_debug;
  
  #define BIER_TEST_I(_cond, _comment, _args...)			\
  ({								\
      int _evald = (_cond);					\
      if (!(_evald)) {						\
          fformat(stderr, "FAIL:%d: " _comment "\n",		\
                  __LINE__, ##_args);				\
          res = 1;                                                \
      } else {							\
          if (bier_test_do_debug)                                 \
              fformat(stderr, "PASS:%d: " _comment "\n",          \
                      __LINE__, ##_args);				\
      }								\
      res;							\
  })
  #define BIER_TEST(_cond, _comment, _args...)			\
  {								\
      if (BIER_TEST_I(_cond, _comment, ##_args)) {		\
          return 1;                                               \
          ASSERT(!("FAIL: " _comment));				\
      }								\
  }
  
  /**
   * A 'i'm not fussed is this is not efficient' store of test data
   */
  typedef struct test_main_t_ {
      /**
       * HW if indicies
       */
      u32 hw_if_indicies[4];
      /**
       * HW interfaces
       */
      vnet_hw_interface_t * hw[4];
  
  } test_main_t;
  static test_main_t test_main;
  
  /* fake ethernet device class, distinct from "fake-ethX" */
  static u8 * format_test_interface_name (u8 * s, va_list * args)
  {
    u32 dev_instance = va_arg (*args, u32);
    return format (s, "test-eth%d", dev_instance);
  }
  
  static uword dummy_interface_tx (vlib_main_t * vm,
                                   vlib_node_runtime_t * node,
                                   vlib_frame_t * frame)
  {
    clib_warning ("you shouldn't be here, leaking buffers...");
    return frame->n_vectors;
  }
  
  VNET_DEVICE_CLASS (test_interface_device_class,static) = {
    .name = "Test interface",
    .format_device_name = format_test_interface_name,
    .tx_function = dummy_interface_tx,
  };
  
  static u8 *hw_address;
  
  static int
  bier_test_mk_intf (u32 ninterfaces)
  {
      clib_error_t * error = NULL;
      test_main_t *tm = &test_main;
      u8 byte;
      int res;
      u32 i;
  
      res = 0;
      ASSERT(ninterfaces <= ARRAY_LEN(tm->hw_if_indicies));
  
      for (i=0; i<6; i++)
      {
          byte = 0xd0+i;
          vec_add1(hw_address, byte);
      }
  
      for (i = 0; i < ninterfaces; i++)
      {
          hw_address[5] = i;
  
          error = ethernet_register_interface(vnet_get_main(),
                                              test_interface_device_class.index,
                                              i /* instance */,
                                              hw_address,
                                              &tm->hw_if_indicies[i],
                                              /* flag change */ 0);
  
          BIER_TEST((NULL == error), "ADD interface %d", i);
  
          tm->hw[i] = vnet_get_hw_interface(vnet_get_main(),
                                            tm->hw_if_indicies[i]);
          vec_validate (ip4_main.fib_index_by_sw_if_index, tm->hw[i]->sw_if_index);
          vec_validate (ip6_main.fib_index_by_sw_if_index, tm->hw[i]->sw_if_index);
          ip4_main.fib_index_by_sw_if_index[tm->hw[i]->sw_if_index] = 0;
          ip6_main.fib_index_by_sw_if_index[tm->hw[i]->sw_if_index] = 0;
          error = vnet_sw_interface_set_flags(vnet_get_main(),
                                              tm->hw[i]->sw_if_index,
                                              VNET_SW_INTERFACE_FLAG_ADMIN_UP);
          BIER_TEST((NULL == error), "UP interface %d", i);
      }
      /*
       * re-eval after the inevitable realloc
       */
      for (i = 0; i < ninterfaces; i++)
      {
          tm->hw[i] = vnet_get_hw_interface(vnet_get_main(),
                                            tm->hw_if_indicies[i]);
      }
  
      return (res);
  }
  
  #define BIER_TEST_LB(_cond, _comment, _args...)			\
  {								\
      if (BIER_TEST_I(_cond, _comment, ##_args)) {		\
          return (1);						\
      }								\
  }
  
  static int
  bier_test_validate_entry (index_t bei,
                            int n_buckets,
                            ...)
  {
      dpo_id_t dpo = DPO_INVALID;
      const load_balance_t *lb;
      va_list ap;
      int res;
  
      va_start(ap, n_buckets);
  
      res = 0;
      bier_entry_contribute_forwarding(bei, &dpo);
  
      res = BIER_TEST_I((DPO_LOAD_BALANCE == dpo.dpoi_type),
                        "Entry links to %U",
                        format_dpo_type, dpo.dpoi_type);
  
      if (!res)
      {
          lb = load_balance_get(dpo.dpoi_index);
          res = fib_test_validate_lb_v(lb, n_buckets, &ap);
      }
  
      dpo_reset(&dpo);
      va_end(ap);
  
      return (res);
  }
  
  static int
  bier_test_mpls_spf (void)
  {
      fib_node_index_t lfei, fei, bti;
      u32 mpls_fib_index;
      test_main_t *tm;
      int lb_count;
      int res;
  
      res = 0;
      lb_count = pool_elts(load_balance_pool);
      tm = &test_main;
  #define N_BIER_ECMP_TABLES 16
      int ii;
  
      /*
       * Add the BIER Main table
       */
      const bier_table_id_t bt_0_0_0_256 = {
          .bti_set = 0,
          .bti_sub_domain = 0,
          .bti_hdr_len = BIER_HDR_LEN_256,
          .bti_type = BIER_TABLE_MPLS_SPF,
          .bti_ecmp = BIER_ECMP_TABLE_ID_MAIN,
      };
  
      bti = bier_table_add_or_lock(&bt_0_0_0_256, 1600);
  
      fib_test_lb_bucket_t l_o_bt[N_BIER_ECMP_TABLES];
      bier_table_id_t bt_ecmp_0_0_0_256 = bt_0_0_0_256;
  
      for (ii = 0; ii < N_BIER_ECMP_TABLES; ii++)
      {
          bt_ecmp_0_0_0_256.bti_ecmp = ii;
  
          l_o_bt[ii].type = FT_LB_BIER_TABLE;
          l_o_bt[ii].bier.table =
              bier_table_ecmp_create_and_lock(&bt_ecmp_0_0_0_256);
      };
      const fib_prefix_t pfx_1600_neos = {
          .fp_len = 21,
          .fp_proto = FIB_PROTOCOL_MPLS,
          .fp_label = 1600,
          .fp_eos = MPLS_NON_EOS,
          .fp_payload_proto = DPO_PROTO_BIER,
      };
      const fib_prefix_t pfx_1600_eos = {
          .fp_len = 21,
          .fp_proto = FIB_PROTOCOL_MPLS,
          .fp_label = 1600,
          .fp_eos = MPLS_EOS,
          .fp_payload_proto = DPO_PROTO_BIER,
      };
  
      mpls_fib_index = fib_table_find(FIB_PROTOCOL_MPLS,
                                      MPLS_FIB_DEFAULT_TABLE_ID);
  
      lfei = fib_table_lookup(mpls_fib_index, &pfx_1600_neos);
      BIER_TEST(FIB_NODE_INDEX_INVALID == lfei, "1600/0 is not present");
  
      lfei = fib_table_lookup(mpls_fib_index, &pfx_1600_eos);
      BIER_TEST(!fib_test_validate_entry(lfei, FIB_FORW_CHAIN_TYPE_MPLS_EOS,
                                         16,
                                         &l_o_bt[0],
                                         &l_o_bt[1],
                                         &l_o_bt[2],
                                         &l_o_bt[3],
                                         &l_o_bt[4],
                                         &l_o_bt[5],
                                         &l_o_bt[6],
                                         &l_o_bt[7],
                                         &l_o_bt[8],
                                         &l_o_bt[9],
                                         &l_o_bt[10],
                                         &l_o_bt[11],
                                         &l_o_bt[12],
                                         &l_o_bt[13],
                                         &l_o_bt[14],
                                         &l_o_bt[15]),
                "1600/1 LB stacks on BIER table %d", bti);
  
      /*
       * modify the table's local label - keep the lock count accurate
       */
      const fib_prefix_t pfx_1601_eos = {
          .fp_len = 21,
          .fp_proto = FIB_PROTOCOL_MPLS,
          .fp_label = 1601,
          .fp_eos = MPLS_EOS,
          .fp_payload_proto = DPO_PROTO_BIER,
      };
      bti = bier_table_add_or_lock(&bt_0_0_0_256, 1601);
      bier_table_unlock(&bt_0_0_0_256);
  
      lfei = fib_table_lookup(mpls_fib_index, &pfx_1600_eos);
      BIER_TEST(FIB_NODE_INDEX_INVALID == lfei, "1600/1 is deleted");
  
      lfei = fib_table_lookup(mpls_fib_index, &pfx_1601_eos);
      BIER_TEST(!fib_test_validate_entry(lfei, FIB_FORW_CHAIN_TYPE_MPLS_EOS,
                                         16,
                                         &l_o_bt[0],
                                         &l_o_bt[1],
                                         &l_o_bt[2],
                                         &l_o_bt[3],
                                         &l_o_bt[4],
                                         &l_o_bt[5],
                                         &l_o_bt[6],
                                         &l_o_bt[7],
                                         &l_o_bt[8],
                                         &l_o_bt[9],
                                         &l_o_bt[10],
                                         &l_o_bt[11],
                                         &l_o_bt[12],
                                         &l_o_bt[13],
                                         &l_o_bt[14],
                                         &l_o_bt[15]),
                "1601/1 LB stacks on BIER table %d", bti);
  
      /*
       * add a route to the table. the via IP route does not exist.
       */
      const ip46_address_t nh_1_1_1_1 = {
          .ip4 = {
              .as_u32 = clib_host_to_net_u32(0x01010101),
          },
      };
      fib_route_path_t *paths_1_1_1_1 = NULL, *input_paths_1_1_1_1;
      fib_route_path_t path_1_1_1_1 = {
          .frp_addr = nh_1_1_1_1,
          .frp_bier_fib_index = bti,
          .frp_sw_if_index = ~0,
      };
      fib_mpls_label_t fml_500 = {
          .fml_value = 500,
      };
      vec_add1(path_1_1_1_1.frp_label_stack, fml_500);
      vec_add1(paths_1_1_1_1, path_1_1_1_1);
      const fib_prefix_t pfx_1_1_1_1_s_32 = {
          .fp_addr = nh_1_1_1_1,
          .fp_len = 32,
          .fp_proto = FIB_PROTOCOL_IP4,
      };
      index_t bei_1;
  
      input_paths_1_1_1_1 = vec_dup(paths_1_1_1_1);
      bier_table_route_path_add(&bt_0_0_0_256, 1, input_paths_1_1_1_1);
      bei_1 = bier_table_lookup(bier_table_get(bti), 1);
  
      BIER_TEST((INDEX_INVALID != bei_1), "BP:1 present");
  
      /*
       * the newly created fmask should stack on the non-eos chain
       * of the via-fib-entry
       */
      dpo_id_t neos_dpo_1_1_1_1 = DPO_INVALID;
      bier_fmask_t *bfm_1_1_1_1;
      index_t bfmi_1_1_1_1;
  
      fei = fib_table_lookup_exact_match(0, &pfx_1_1_1_1_s_32);
      fib_entry_contribute_forwarding(fei,
                                      FIB_FORW_CHAIN_TYPE_MPLS_NON_EOS,
                                      &neos_dpo_1_1_1_1);
  
      bfmi_1_1_1_1 = bier_fmask_db_find(bti, &path_1_1_1_1);
      bfm_1_1_1_1 = bier_fmask_get(bfmi_1_1_1_1);
  
      BIER_TEST(!dpo_cmp(drop_dpo_get(DPO_PROTO_MPLS),
                         &bfm_1_1_1_1->bfm_dpo),
                "Fmask via 1.1.1.1 stacks on MPLS drop");
  
      /*
       * The BIER entry should stack on the forwarding chain of the fmask
       */
      const fib_test_lb_bucket_t dpo_o_bfm_1_1_1_1 = {
          .type = FT_LB_BIER_FMASK,
          .bier = {
              .fmask = bfmi_1_1_1_1,
          },
      };
      dpo_id_t dpo_bei = DPO_INVALID;
      bier_entry_contribute_forwarding(bei_1, &dpo_bei);
  
      BIER_TEST(!dpo_cmp(&dpo_bei, drop_dpo_get(DPO_PROTO_BIER)),
                "BP:1 stacks on bier drop");
  
      /*
       * give 1.1.1.1/32 a path and hence a interesting n-eos chain
       */
      ip46_address_t nh_10_10_10_1 = {
          .ip4 = {
              .as_u32 = clib_host_to_net_u32(0x0a0a0a01),
          },
      };
      adj_index_t ai_mpls_10_10_10_1;
      ai_mpls_10_10_10_1 = adj_nbr_add_or_lock(FIB_PROTOCOL_IP4,
                                               VNET_LINK_MPLS,
                                               &nh_10_10_10_1,
                                               tm->hw[0]->sw_if_index);
  
      fib_test_lb_bucket_t bucket_neos_99_via_10_10_10_1 = {
          .type = FT_LB_LABEL_O_ADJ,
          .label_o_adj = {
              .label = 99,
              .eos = MPLS_NON_EOS,
              .adj = ai_mpls_10_10_10_1,
              .ttl = 255,
          },
      };
      fib_mpls_label_t *out_lbl_99 = NULL, fml_99 = {
          .fml_value = 99,
      };
      vec_add1(out_lbl_99, fml_99);
  
      fei = fib_table_entry_update_one_path(0,
                                            &pfx_1_1_1_1_s_32,
                                            FIB_SOURCE_API,
                                            FIB_ENTRY_FLAG_NONE,
                                            DPO_PROTO_IP4,
                                            &nh_10_10_10_1,
                                            tm->hw[0]->sw_if_index,
                                            ~0, // invalid fib index
                                            1,
                                            out_lbl_99,
                                            FIB_ROUTE_PATH_FLAG_NONE);
      fib_entry_contribute_forwarding(fei,
                                      FIB_FORW_CHAIN_TYPE_MPLS_NON_EOS,
                                      &neos_dpo_1_1_1_1);
      BIER_TEST(!fib_test_validate_lb(&neos_dpo_1_1_1_1, 1,
                                      &bucket_neos_99_via_10_10_10_1),
                "1.1.1.1/32 n-eos LB 1 buckets via: 99 + 10.10.10.1");
      BIER_TEST(!dpo_cmp(&neos_dpo_1_1_1_1,
                         &bfm_1_1_1_1->bfm_dpo),
                "Fmask via 1.1.1.1 stacks on updated non-eos of 1.1.1.1/32");
      bier_entry_contribute_forwarding(bei_1, &dpo_bei);
      BIER_TEST((dpo_bei.dpoi_index == bfmi_1_1_1_1),
                "BP:1  stacks on fmask 1.1.1.1");
  
      /*
       * add another path to the via entry.
       * this makes the via-entry instantiate a new load-balance with
       * 2 buckets. and the back-walk to the BIER entry will need to
       * re-stack on it.
       */
      ip46_address_t nh_10_10_10_2 = {
          .ip4 = {
              .as_u32 = clib_host_to_net_u32(0x0a0a0a02),
          },
      };
      adj_index_t ai_mpls_10_10_10_2;
  
      ai_mpls_10_10_10_2 = adj_nbr_add_or_lock(FIB_PROTOCOL_IP4,
                                               VNET_LINK_MPLS,
                                               &nh_10_10_10_2,
                                               tm->hw[0]->sw_if_index);
  
      fib_test_lb_bucket_t bucket_neos_100_via_10_10_10_2 = {
          .type = FT_LB_LABEL_O_ADJ,
          .label_o_adj = {
              .label = 100,
              .eos = MPLS_NON_EOS,
              .adj = ai_mpls_10_10_10_2,
              .ttl = 255,
          },
      };
      fib_mpls_label_t *out_lbl_100 = NULL, fml_100 = {
          .fml_value = 100,
      };
      vec_add1(out_lbl_100, fml_100);
  
      fei = fib_table_entry_path_add(0,
                                     &pfx_1_1_1_1_s_32,
                                     FIB_SOURCE_API,
                                     FIB_ENTRY_FLAG_NONE,
                                     DPO_PROTO_IP4,
                                     &nh_10_10_10_2,
                                     tm->hw[0]->sw_if_index,
                                     ~0, // invalid fib index
                                     1,
                                     out_lbl_100,
                                     FIB_ROUTE_PATH_FLAG_NONE);
  
      fib_entry_contribute_forwarding(fei,
                                      FIB_FORW_CHAIN_TYPE_MPLS_NON_EOS,
                                      &neos_dpo_1_1_1_1);
      BIER_TEST(!fib_test_validate_lb(&neos_dpo_1_1_1_1, 2,
                                      &bucket_neos_99_via_10_10_10_1,
                                      &bucket_neos_100_via_10_10_10_2),
                "1.1.1.1/32 n-eos LB 2 buckets "
                "via: 99 + 10.10.10.1, "
                "via: 100 + 10.10.10.2");
      BIER_TEST(!dpo_cmp(&neos_dpo_1_1_1_1,
                         &bfm_1_1_1_1->bfm_dpo),
                "Fmask via 1.1.1.1 stacks on updated non-eos of 1.1.1.1/32");
  
      /*
       * add another bier bit-position via the same next-hop
       * since its the same next hop, the two bit-positions should link
       * to the same fmask
       */
      index_t bei_2;
  
      input_paths_1_1_1_1 = vec_dup(paths_1_1_1_1);
      bier_table_route_path_add(&bt_0_0_0_256, 2, input_paths_1_1_1_1);
      bei_2 = bier_table_lookup(bier_table_get(bti), 2);
  
      bier_entry_contribute_forwarding(bei_2, &dpo_bei);
      BIER_TEST((dpo_bei.dpoi_index == bfmi_1_1_1_1),
                "BP:2  stacks on fmask 1.1.1.1");
  
      /*
       * now add a bit-position via a different next hop and expect to
       * link via a different fmask
       */
      const ip46_address_t nh_1_1_1_2 = {
          .ip4 = {
              .as_u32 = clib_host_to_net_u32(0x01010102),
          },
      };
      const fib_prefix_t pfx_1_1_1_2_s_32 = {
          .fp_addr = nh_1_1_1_2,
          .fp_len = 32,
          .fp_proto = FIB_PROTOCOL_IP4,
      };
      fib_route_path_t *paths_1_1_1_2 = NULL, *input_paths_1_1_1_2, path_1_1_1_2 = {
          .frp_addr = nh_1_1_1_2,
          .frp_bier_fib_index = bti,
          .frp_sw_if_index = ~0,
      };
      fib_mpls_label_t fml_501 = {
          .fml_value = 501,
      };
      vec_add1(path_1_1_1_2.frp_label_stack, fml_501);
      vec_add1(paths_1_1_1_2, path_1_1_1_2);
      input_paths_1_1_1_2 = vec_dup(paths_1_1_1_2);
      index_t bei_3;
  
      fib_mpls_label_t *out_lbl_101 = NULL, fml_101 = {
          .fml_value = 101,
      };
      vec_add1(out_lbl_101, fml_101);
      fei = fib_table_entry_path_add(0,
                                     &pfx_1_1_1_2_s_32,
                                     FIB_SOURCE_API,
                                     FIB_ENTRY_FLAG_NONE,
                                     DPO_PROTO_IP4,
                                     &nh_10_10_10_2,
                                     tm->hw[0]->sw_if_index,
                                     ~0, // invalid fib index
                                     1,
                                     out_lbl_101,
                                     FIB_ROUTE_PATH_FLAG_NONE);
      bier_table_route_path_update(&bt_0_0_0_256, 3, input_paths_1_1_1_2);
      bei_3 = bier_table_lookup(bier_table_get(bti), 3);
  
      BIER_TEST((INDEX_INVALID != bei_3), "BP:3 present");
  
      /*
       * the newly created fmask should stack on the non-eos chain
       * of the via-fib-entry
       */
      dpo_id_t neos_dpo_1_1_1_2 = DPO_INVALID;
      bier_fmask_t *bfm_1_1_1_2;
      index_t bfmi_1_1_1_2;
  
      fei = fib_table_lookup_exact_match(0, &pfx_1_1_1_2_s_32);
      fib_entry_contribute_forwarding(fei,
                                      FIB_FORW_CHAIN_TYPE_MPLS_NON_EOS,
                                      &neos_dpo_1_1_1_2);
  
      bfmi_1_1_1_2 = bier_fmask_db_find(bti, &path_1_1_1_2);
      bfm_1_1_1_2 = bier_fmask_get(bfmi_1_1_1_2);
  
      BIER_TEST(!dpo_cmp(&neos_dpo_1_1_1_2,
                         &bfm_1_1_1_2->bfm_dpo),
                "Fmask via 1.1.1.2 stacks on non-eos of 1.1.1.2/32");
  
      /*
       * The BIER entry should stack on the forwarding chain of the fmask
       */
      const fib_test_lb_bucket_t dpo_o_bfm_1_1_1_2 = {
          .type = FT_LB_BIER_FMASK,
          .bier = {
              .fmask = bfmi_1_1_1_2,
          },
      };
      bier_entry_contribute_forwarding(bei_3, &dpo_bei);
      BIER_TEST((dpo_bei.dpoi_index == bfmi_1_1_1_2),
                "BP:2 stacks on fmask 1.1.1.2");
  
      /*
       * Load-balance BP:3 over both next-hops
       */
      paths_1_1_1_1[0] = path_1_1_1_1;
      input_paths_1_1_1_1 = vec_dup(paths_1_1_1_1);
      bier_table_route_path_add(&bt_0_0_0_256, 3, input_paths_1_1_1_1);
  
      BIER_TEST(!bier_test_validate_entry(bei_3, 2,
                                          &dpo_o_bfm_1_1_1_1,
                                          &dpo_o_bfm_1_1_1_2),
                "BP:3 stacks on fmask 1.1.1.2 & 1.1.1.1");
  
      /*
       * test that the ECMP choices for BP:3 have been spread over the
       * ECMP tables
       */
      BIER_TEST((bier_table_fwd_lookup(bier_table_get(l_o_bt[0].bier.table), 3) ==
                 bfmi_1_1_1_1),
                "fwd lookup for BP:3 ECMP:0 is 1.1.1.1");
      BIER_TEST((bier_table_fwd_lookup(bier_table_get(l_o_bt[1].bier.table), 3) ==
                 bfmi_1_1_1_2),
                "fwd lookup for BP:3 ECMP:1 is 1.1.1.2");
  
      /*
       * Withdraw one of the via FIB and thus bring down the fmask
       * expect the bier-entry forwarding to remove this from the set
       */
      fib_table_entry_delete(0, &pfx_1_1_1_2_s_32, FIB_SOURCE_API);
  
      bier_entry_contribute_forwarding(bei_3, &dpo_bei);
      BIER_TEST((dpo_bei.dpoi_index == bfmi_1_1_1_1),
                "BP:3 stacks on fmask 1.1.1.1");
  
      BIER_TEST((bier_table_fwd_lookup(bier_table_get(l_o_bt[0].bier.table), 3) ==
                 bfmi_1_1_1_1),
                "fwd lookup for BP:3 ECMP:0 is 1.1.1.1");
      BIER_TEST((bier_table_fwd_lookup(bier_table_get(l_o_bt[1].bier.table), 3) ==
                 bfmi_1_1_1_1),
                "fwd lookup for BP:3 ECMP:1 is 1.1.1.1");
  
      /*
       * add the via back
       */
      out_lbl_101 = NULL;
      vec_add1(out_lbl_101, fml_101);
      fei = fib_table_entry_path_add(0,
                                     &pfx_1_1_1_2_s_32,
                                     FIB_SOURCE_API,
                                     FIB_ENTRY_FLAG_NONE,
                                     DPO_PROTO_IP4,
                                     &nh_10_10_10_2,
                                     tm->hw[0]->sw_if_index,
                                     ~0, // invalid fib index
                                     1,
                                     out_lbl_101,
                                     FIB_ROUTE_PATH_FLAG_NONE);
      /* suspend so the update walk kicks int */
      vlib_process_suspend(vlib_get_main(), 1e-5);
  
      BIER_TEST(!bier_test_validate_entry(bei_3, 2,
                                          &dpo_o_bfm_1_1_1_1,
                                          &dpo_o_bfm_1_1_1_2),
                "BP:3 stacks on fmask 1.1.1.2 & 1.1.1.1");
      BIER_TEST((bier_table_fwd_lookup(bier_table_get(l_o_bt[0].bier.table), 3) ==
                 bfmi_1_1_1_1),
                "fwd lookup for BP:3 ECMP:0 is 1.1.1.1");
      BIER_TEST((bier_table_fwd_lookup(bier_table_get(l_o_bt[1].bier.table), 3) ==
                 bfmi_1_1_1_2),
                "fwd lookup for BP:3 ECMP:1 is 1.1.1.2");
  
      /*
       * remove the original 1.1.1.2 fmask from BP:3
       */
      input_paths_1_1_1_2 = vec_dup(paths_1_1_1_2);
      bier_table_route_path_remove(&bt_0_0_0_256, 3, input_paths_1_1_1_2);
      bier_entry_contribute_forwarding(bei_3, &dpo_bei);
      BIER_TEST((dpo_bei.dpoi_index == bfmi_1_1_1_1),
                "BP:3 stacks on fmask 1.1.1.1");
  
      /*
       * test that the ECMP choices for BP:3 have been updated
       */
      BIER_TEST((bier_table_fwd_lookup(bier_table_get(l_o_bt[0].bier.table), 3) ==
                 bfmi_1_1_1_1),
                "fwd lookup for BP:3 ECMP:0 is 1.1.1.1");
      BIER_TEST((bier_table_fwd_lookup(bier_table_get(l_o_bt[1].bier.table), 3) ==
                 bfmi_1_1_1_1),
                "fwd lookup for BP:3 ECMP:1 is 1.1.1.1");
  
      /*
       * remove the routes added
       */
      input_paths_1_1_1_1 = vec_dup(paths_1_1_1_1);
      bier_table_route_path_remove(&bt_0_0_0_256, 2, input_paths_1_1_1_1);
      input_paths_1_1_1_2 = vec_dup(paths_1_1_1_2);
      bier_table_route_path_remove(&bt_0_0_0_256, 3, input_paths_1_1_1_2);
      input_paths_1_1_1_1 = vec_dup(paths_1_1_1_1);
      bier_table_route_path_remove(&bt_0_0_0_256, 3, input_paths_1_1_1_1);
  
      bier_table_route_delete(&bt_0_0_0_256, 1);
  
      /*
       * delete the table
       */
      bier_table_unlock(&bt_0_0_0_256);
  
      /*
       * test resources are freed
       */
      dpo_reset(&dpo_bei);
      for (ii = 0; ii < N_BIER_ECMP_TABLES; ii++)
      {
          bier_table_ecmp_unlock(l_o_bt[ii].bier.table);
      };
      BIER_TEST(0 == pool_elts(bier_table_pool), "BIER table pool empty");
      BIER_TEST(0 == pool_elts(bier_fmask_pool), "BIER fmask pool empty");
      BIER_TEST(0 == pool_elts(bier_entry_pool), "BIER entry pool empty");
  
      adj_unlock(ai_mpls_10_10_10_1);
      adj_unlock(ai_mpls_10_10_10_2);
      dpo_reset(&neos_dpo_1_1_1_1);
      dpo_reset(&neos_dpo_1_1_1_2);
      fib_table_entry_delete(0, &pfx_1_1_1_1_s_32, FIB_SOURCE_API);
      fib_table_entry_delete(0, &pfx_1_1_1_2_s_32, FIB_SOURCE_API);
  
      /* +1 to account for the one time alloc'd drop LB in the MPLS fibs */
      BIER_TEST(lb_count+1 == pool_elts(load_balance_pool),
                "Load-balance resources freed ");
      BIER_TEST((0 == adj_nbr_db_size()), "ADJ DB size is %d",
               adj_nbr_db_size());
  
      vec_free(paths_1_1_1_1);
      vec_free(paths_1_1_1_2);
      vec_free(input_paths_1_1_1_1);
      vec_free(input_paths_1_1_1_2);
  
      return (0);
  }
  
  static int
  bier_test_mpls_imp (void)
  {
      fib_node_index_t bii;
      int res;
  
      /*
       * Add the BIER Main table
       */
      const bier_table_id_t bt_0_0_0_256 = {
          .bti_set = 0,
          .bti_sub_domain = 0,
          .bti_hdr_len = BIER_HDR_LEN_256,
          .bti_type = BIER_TABLE_MPLS_SPF,
          .bti_ecmp = BIER_ECMP_TABLE_ID_MAIN,
      };
  
      bier_table_add_or_lock(&bt_0_0_0_256, 1600);
  
      /*
       * A bit-string for imp 1.
       */
      bier_bit_string_t bbs_256;
      u8 buckets[BIER_HDR_BUCKETS_256];
      memset(buckets, 0x5, BIER_HDR_BUCKETS_256);
  
      res = 0;
      bier_bit_string_init(&bbs_256, BIER_HDR_LEN_256, buckets);
  
      bii = bier_imp_add_or_lock(&bt_0_0_0_256, 1, &bbs_256);
  
      /*
       * An mfib entry that resolves via the BIER imposition
       */
      const mfib_prefix_t pfx_1_1_1_1_c_239_1_1_1 = {
          .fp_len = 64,
          .fp_proto = FIB_PROTOCOL_IP4,
          .fp_grp_addr = {
              .ip4.as_u32 = clib_host_to_net_u32(0xef010101),
          },
          .fp_src_addr = {
              .ip4.as_u32 = clib_host_to_net_u32(0x01010101),
          },
      };
      fib_route_path_t path_via_bier_imp_1 = {
          .frp_proto = DPO_PROTO_BIER,
          .frp_bier_imp = bii,
          .frp_weight = 0,
          .frp_flags = FIB_ROUTE_PATH_BIER_IMP,
      };
      mfib_table_entry_path_update(0, // default table
                                   &pfx_1_1_1_1_c_239_1_1_1 ,
                                   MFIB_SOURCE_API,
                                   &path_via_bier_imp_1,
                                   MFIB_ITF_FLAG_FORWARD);
      mfib_table_entry_delete(0,
                              &pfx_1_1_1_1_c_239_1_1_1 ,
                              MFIB_SOURCE_API);
  
      bier_imp_unlock(bii);
      bier_table_unlock(&bt_0_0_0_256);
  
      BIER_TEST(0 == pool_elts(bier_imp_pool),
                "BIER imposition resources freed ");
      BIER_TEST(0 == pool_elts(bier_table_pool),
                "BIER table resources freed ");
  
      return (0);
  }
  
  static int
  bier_test_mpls_disp (void)
  {
      /*
       * Add the BIER Main table
       */
      const bier_table_id_t bt_0_0_0_256 = {
          .bti_set = 0,
          .bti_sub_domain = 0,
          .bti_hdr_len = BIER_HDR_LEN_256,
          .bti_type = BIER_TABLE_MPLS_SPF,
          .bti_ecmp = BIER_ECMP_TABLE_ID_MAIN,
      };
      index_t bti;
      int res;
  
      res = 0;
      bti = bier_table_add_or_lock(&bt_0_0_0_256, 1600);
  
      /*
       * Add a BIER dispoition table
       */
      const u32 bier_disp_tbl_id = 1;
      index_t bdti1;
  
      bdti1 = bier_disp_table_add_or_lock(bier_disp_tbl_id);
  
      /*
       * add a bit-poistion in the table that resolves via
       * DISP table, i.e. a for-us bit-position
       */
      fib_route_path_t *paths_via_disp = NULL, path_via_disp = {
          // .frp_addr = all-zeros
          .frp_proto = DPO_PROTO_BIER,
          .frp_bier_fib_index = bdti1,
          .frp_sw_if_index = ~0,
      };
      vec_add1(paths_via_disp, path_via_disp);
  
      bier_table_route_path_add(&bt_0_0_0_256, 3, paths_via_disp);
  
      /*
       * the fmask should stack on the BIER disp table
       */
      bier_fmask_t *bfm_0_0_0_0;
      index_t bfmi_0_0_0_0;
      dpo_id_t dpo_disp_tbl_1 = DPO_INVALID;
  
      bier_disp_table_contribute_forwarding(bdti1, &dpo_disp_tbl_1);
  
      bfmi_0_0_0_0 = bier_fmask_db_find(bti, &path_via_disp);
      bfm_0_0_0_0 = bier_fmask_get(bfmi_0_0_0_0);
  
      BIER_TEST(!dpo_cmp(&dpo_disp_tbl_1, &bfm_0_0_0_0->bfm_dpo),
                "Fmask via 0.0.0.0 stacks on BIER disp table 1");
  
      /*
       * and a deag entry into the disposition table
       */
      fib_route_path_t *rpaths = NULL, path_via_mfib = {
          .frp_proto = DPO_PROTO_IP4,
          .frp_addr = zero_addr,
          .frp_fib_index = 0, // default MFIB table
          .frp_rpf_id = 9, // some non-zero value
          .frp_flags = FIB_ROUTE_PATH_RPF_ID,
      };
      bier_hdr_src_id_t src = 99;
      vec_add1(rpaths, path_via_mfib);
      bier_disp_table_entry_path_add(bier_disp_tbl_id, src,
                                     BIER_HDR_PROTO_IPV4, rpaths);
  
      /* which should stack on a lookup in the mfib table */
      const dpo_id_t *dpo_disp_entry_v4;
      bier_disp_entry_t *bde_99;
      index_t bdei;
  
      bdei = bier_disp_table_lookup(bdti1, clib_host_to_net_u16(src));
      bde_99 = bier_disp_entry_get(bdei);
      dpo_disp_entry_v4 = &bde_99->bde_fwd[BIER_HDR_PROTO_IPV4].bde_dpo;
  
      lookup_dpo_t *lkd = lookup_dpo_get(dpo_disp_entry_v4->dpoi_index);
  
      BIER_TEST((bdti1 == lkd->lkd_fib_index),
                "disp is deag in %d %U",
                lkd->lkd_fib_index,
                format_dpo_id, dpo_disp_entry_v4, 0);
      BIER_TEST((LOOKUP_INPUT_DST_ADDR == lkd->lkd_input),
                "disp is destination deag in %d %U",
                lkd->lkd_input,
                format_dpo_id, dpo_disp_entry_v4, 0);
      BIER_TEST((LOOKUP_MULTICAST == lkd->lkd_cast),
                "disp is multicast deag in %d %U",
                lkd->lkd_input,
                format_dpo_id, dpo_disp_entry_v4, 0);
  
      /*
       * cleanup
       */
      dpo_reset(&dpo_disp_tbl_1);
  
      bier_disp_table_entry_path_remove(bier_disp_tbl_id, src,
                                        BIER_HDR_PROTO_IPV4, rpaths);
      bier_table_route_path_remove(&bt_0_0_0_256, 3, paths_via_disp);
  
      bier_disp_table_unlock_w_table_id(bier_disp_tbl_id);
  
      bier_table_unlock(&bt_0_0_0_256);
  
      BIER_TEST(0 == pool_elts(bier_fmask_pool),
                "BIER fmask resources freed ");
      BIER_TEST(0 == pool_elts(bier_table_pool),
                "BIER table resources freed ");
      BIER_TEST(0 == pool_elts(bier_disp_table_pool),
                "BIER Disposition table resources freed ");
      BIER_TEST(0 == pool_elts(bier_disp_entry_pool),
                "BIER Disposition entry resources freed ");
  
      vec_free(paths_via_disp);
      return (0);
  }
  
  static clib_error_t *
  bier_test (vlib_main_t * vm,
             unformat_input_t * input,
             vlib_cli_command_t * cmd_arg)
  {
      int res = 0;
  
      res += bier_test_mk_intf(4);
  
      if (unformat (input, "debug"))
      {
          bier_test_do_debug = 1;
      }
  
      if (unformat (input, "mid"))
          res += bier_test_mpls_spf();
      else if (unformat (input, "head"))
          res += bier_test_mpls_imp();
      else if (unformat (input, "tail"))
          res += bier_test_mpls_disp();
      else
      {
          res += bier_test_mpls_spf();
          res += bier_test_mpls_imp();
          res += bier_test_mpls_disp();
      }
  
      if (res)
      {
          return clib_error_return(0, "BIER Unit Test Failed");
      }
      else
      {
          return (NULL);
      }
  }
  
  VLIB_CLI_COMMAND (test_route_command, static) = {
      .path = "test bier",
      .short_help = "bier unit tests",
      .function = bier_test,
  };
  
  clib_error_t *
  bier_test_init (vlib_main_t *vm)
  {
      return 0;
  }
  
  VLIB_INIT_FUNCTION (bier_test_init);
  