/*
 * 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/session/application_interface.h>

#include <vnet/session/session.h>
#include <vlibmemory/api.h>
#include <vnet/dpo/load_balance.h>

/** @file
    VPP's application/session API bind/unbind/connect/disconnect calls
*/

/*
 * TLS server cert and keys to be used for testing only
 */
const char test_srv_crt_rsa[] =
  "-----BEGIN CERTIFICATE-----\r\n"
  "MIID5zCCAs+gAwIBAgIJALeMYCEHrTtJMA0GCSqGSIb3DQEBCwUAMIGJMQswCQYD\r\n"
  "VQQGEwJVUzELMAkGA1UECAwCQ0ExETAPBgNVBAcMCFNhbiBKb3NlMQ4wDAYDVQQK\r\n"
  "DAVDaXNjbzEOMAwGA1UECwwFZmQuaW8xFjAUBgNVBAMMDXRlc3R0bHMuZmQuaW8x\r\n"
  "IjAgBgkqhkiG9w0BCQEWE3ZwcC1kZXZAbGlzdHMuZmQuaW8wHhcNMTgwMzA1MjEx\r\n"
  "NTEyWhcNMjgwMzAyMjExNTEyWjCBiTELMAkGA1UEBhMCVVMxCzAJBgNVBAgMAkNB\r\n"
  "MREwDwYDVQQHDAhTYW4gSm9zZTEOMAwGA1UECgwFQ2lzY28xDjAMBgNVBAsMBWZk\r\n"
  "LmlvMRYwFAYDVQQDDA10ZXN0dGxzLmZkLmlvMSIwIAYJKoZIhvcNAQkBFhN2cHAt\r\n"
  "ZGV2QGxpc3RzLmZkLmlvMIIBIjANBgkqhkiG9w0BAQEFAAOCAQ8AMIIBCgKCAQEA\r\n"
  "4C1k8a1DuStgggqT4o09fP9sJ2dC54bxhS/Xk2VEfaIZ222WSo4X/syRVfVy9Yah\r\n"
  "cpI1zJ/RDxaZSFhgA+nPZBrFMsrULkrdAOpOVj8eDEp9JuWdO2ODSoFnCvLxcYWB\r\n"
  "Yc5kHryJpEaGJl1sFQSesnzMFty/59ta0stk0Fp8r5NhIjWvSovGzPo6Bhz+VS2c\r\n"
  "ebIZh4x1t2hHaFcgm0qJoJ6DceReWCW8w+yOVovTolGGq+bpb2Hn7MnRSZ2K2NdL\r\n"
  "+aLXpkZbS/AODP1FF2vTO1mYL290LO7/51vJmPXNKSDYMy5EvILr5/VqtjsFCwRL\r\n"
  "Q4jcM/+GeHSAFWx4qIv0BwIDAQABo1AwTjAdBgNVHQ4EFgQUWa1SOB37xmT53tZQ\r\n"
  "aXuLLhRI7U8wHwYDVR0jBBgwFoAUWa1SOB37xmT53tZQaXuLLhRI7U8wDAYDVR0T\r\n"
  "BAUwAwEB/zANBgkqhkiG9w0BAQsFAAOCAQEAoUht13W4ya27NVzQuCMvqPWL3VM4\r\n"
  "3xbPFk02FaGz/WupPu276zGlzJAZrbuDcQowwwU1Ni1Yygxl96s1c2M5rHDTrOKG\r\n"
  "rK0hbkSFBo+i6I8u4HiiQ4rYmG0Hv6+sXn3of0HsbtDPGgWZoipPWDljPYEURu3e\r\n"
  "3HRe/Dtsj9CakBoSDzs8ndWaBR+f4sM9Tk1cjD46Gq2T/qpSPXqKxEUXlzhdCAn4\r\n"
  "twub17Bq2kykHpppCwPg5M+v30tHG/R2Go15MeFWbEJthFk3TZMjKL7UFs7fH+x2\r\n"
  "wSonXb++jY+KmCb93C+soABBizE57g/KmiR2IxQ/LMjDik01RSUIaM0lLA==\r\n"
  "-----END CERTIFICATE-----\r\n";
const u32 test_srv_crt_rsa_len = sizeof (test_srv_crt_rsa);

const char test_srv_key_rsa[] =
  "-----BEGIN PRIVATE KEY-----\r\n"
  "MIIEvQIBADANBgkqhkiG9w0BAQEFAASCBKcwggSjAgEAAoIBAQDgLWTxrUO5K2CC\r\n"
  "CpPijT18/2wnZ0LnhvGFL9eTZUR9ohnbbZZKjhf+zJFV9XL1hqFykjXMn9EPFplI\r\n"
  "WGAD6c9kGsUyytQuSt0A6k5WPx4MSn0m5Z07Y4NKgWcK8vFxhYFhzmQevImkRoYm\r\n"
  "XWwVBJ6yfMwW3L/n21rSy2TQWnyvk2EiNa9Ki8bM+joGHP5VLZx5shmHjHW3aEdo\r\n"
  "VyCbSomgnoNx5F5YJbzD7I5Wi9OiUYar5ulvYefsydFJnYrY10v5otemRltL8A4M\r\n"
  "/UUXa9M7WZgvb3Qs7v/nW8mY9c0pINgzLkS8guvn9Wq2OwULBEtDiNwz/4Z4dIAV\r\n"
  "bHioi/QHAgMBAAECggEBAMzGipP8+oT166U+NlJXRFifFVN1DvdhG9PWnOxGL+c3\r\n"
  "ILmBBC08WQzmHshPemBvR6DZkA1H23cV5JTiLWrFtC00CvhXsLRMrE5+uWotI6yE\r\n"
  "iofybMroHvD6/X5R510UX9hQ6MHu5ShLR5VZ9zXHz5MpTmB/60jG5dLx+jgcwBK8\r\n"
  "LuGv2YB/WCUwT9QJ3YU2eaingnXtz/MrFbkbltrqlnBdlD+kTtw6Yac9y1XuuQXc\r\n"
  "BPeulLNDuPolJVWbUvDBZrpt2dXTgz8ws1sv+wCNE0xwQJsqW4Nx3QkpibUL9RUr\r\n"
  "CVbKlNfa9lopT6nGKlgX69R/uH35yh9AOsfasro6w0ECgYEA82UJ8u/+ORah+0sF\r\n"
  "Q0FfW5MTdi7OAUHOz16pUsGlaEv0ERrjZxmAkHA/VRwpvDBpx4alCv0Hc39PFLIk\r\n"
  "nhSsM2BEuBkTAs6/GaoNAiBtQVE/hN7awNRWVmlieS0go3Y3dzaE9IUMyj8sPOFT\r\n"
  "5JdJ6BM69PHKCkY3dKdnnfpFEuECgYEA68mRpteunF1mdZgXs+WrN+uLlRrQR20F\r\n"
  "ZyMYiUCH2Dtn26EzA2moy7FipIIrQcX/j+KhYNGM3e7MU4LymIO29E18mn8JODnH\r\n"
  "sQOXzBTsf8A4yIVMkcuQD3bfb0JiUGYUPOidTp2N7IJA7+6Yc3vQOyb74lnKnJoO\r\n"
  "gougPT2wS+cCgYAn7muzb6xFsXDhyW0Tm6YJYBfRS9yAWEuVufINobeBZPSl2cN1\r\n"
  "Jrnw+HlrfTNbrJWuJmjtZJXUXQ6cVp2rUbjutNyRV4vG6iRwEXYQ40EJdkr1gZpi\r\n"
  "CHQhuShuuPih2MNAy7EEbM+sXrDjTBR3bFqzuHPzu7dp+BshCFX3lRfAAQKBgGQt\r\n"
  "K5i7IhCFDjb/+3IPLgOAK7mZvsvZ4eXD33TQ2eZgtut1PXtBtNl17/b85uv293Fm\r\n"
  "VDISVcsk3eLNS8zIiT6afUoWlxAwXEs0v5WRfjl4radkGvgGiJpJYvyeM67877RB\r\n"
  "EDSKc/X8ESLfOB44iGvZUEMG6zJFscx9DgN25iQZAoGAbyd+JEWwdVH9/K3IH1t2\r\n"
  "PBkZX17kNWv+iVM1WyFjbe++vfKZCrOJiyiqhDeEqgrP3AuNMlaaduC3VRC3G5oV\r\n"
  "Mj1tlhDWQ/qhvKdCKNdIVQYDE75nw+FRWV8yYkHAnXYW3tNoweDIwixE0hkPR1bc\r\n"
  "oEjPLVNtx8SOj/M4rhaPT3I=\r\n" "-----END PRIVATE KEY-----\r\n";
const u32 test_srv_key_rsa_len = sizeof (test_srv_key_rsa);

static u8
session_endpoint_is_local (session_endpoint_t * sep)
{
  return (ip_is_zero (&sep->ip, sep->is_ip4)
	  || ip_is_local_host (&sep->ip, sep->is_ip4));
}

static u8
session_endpoint_is_zero (session_endpoint_t * sep)
{
  return ip_is_zero (&sep->ip, sep->is_ip4);
}

u8
session_endpoint_in_ns (session_endpoint_t * sep)
{
  u8 is_lep = session_endpoint_is_local (sep);
  if (!is_lep && sep->sw_if_index != ENDPOINT_INVALID_INDEX
      && !ip_interface_has_address (sep->sw_if_index, &sep->ip, sep->is_ip4))
    {
      clib_warning ("sw_if_index %u not configured with ip %U",
		    sep->sw_if_index, format_ip46_address, &sep->ip,
		    sep->is_ip4);
      return 0;
    }
  return (is_lep || ip_is_local (sep->fib_index, &sep->ip, sep->is_ip4));
}

int
api_parse_session_handle (u64 handle, u32 * session_index, u32 * thread_index)
{
  session_manager_main_t *smm = vnet_get_session_manager_main ();
  stream_session_t *pool;

  *thread_index = handle & 0xFFFFFFFF;
  *session_index = handle >> 32;

  if (*thread_index >= vec_len (smm->sessions))
    return VNET_API_ERROR_INVALID_VALUE;

  pool = smm->sessions[*thread_index];

  if (pool_is_free_index (pool, *session_index))
    return VNET_API_ERROR_INVALID_VALUE_2;

  return 0;
}

static void
session_endpoint_update_for_app (session_endpoint_t * sep,
				 application_t * app)
{
  app_namespace_t *app_ns;
  app_ns = app_namespace_get (app->ns_index);
  if (app_ns)
    {
      /* Ask transport and network to bind to/connect using local interface
       * that "supports" app's namespace. This will fix our local connection
       * endpoint.
       */
      sep->sw_if_index = app_ns->sw_if_index;
      sep->fib_index =
	sep->is_ip4 ? app_ns->ip4_fib_index : app_ns->ip6_fib_index;
    }
}

static int
vnet_bind_i (u32 app_index, session_endpoint_t * sep, u64 * handle)
{
  u64 lh, ll_handle = SESSION_INVALID_HANDLE;
  application_t *app;
  u32 table_index;
  int rv;

  app = application_get_if_valid (app_index);
  if (!app)
    {
      SESSION_DBG ("app not attached");
      return VNET_API_ERROR_APPLICATION_NOT_ATTACHED;
    }

  session_endpoint_update_for_app (sep, app);
  if (!session_endpoint_in_ns (sep))
    return VNET_API_ERROR_INVALID_VALUE_2;

  table_index = application_session_table (app,
					   session_endpoint_fib_proto (sep));
  lh = session_lookup_endpoint_listener (table_index, sep, 1);
  if (lh != SESSION_INVALID_HANDLE)
    return VNET_API_ERROR_ADDRESS_IN_USE;

  /*
   * Add session endpoint to local session table. Only binds to "inaddr_any"
   * (i.e., zero address) are added to local scope table.
   */
  if (application_has_local_scope (app) && session_endpoint_is_local (sep))
    {
      if ((rv = application_start_local_listen (app, sep, handle)))
	return rv;
      ll_handle = *handle;
    }

  if (!application_has_global_scope (app))
    return (ll_handle == SESSION_INVALID_HANDLE ? -1 : 0);

  /*
   * Add session endpoint to global session table
   */

  /* Setup listen path down to transport */
  rv = application_start_listen (app, sep, handle);
  if (rv && ll_handle != SESSION_INVALID_HANDLE)
    session_lookup_del_session_endpoint (table_index, sep);

  /*
   * Store in local table listener the index of the transport layer
   * listener. We'll need local listeners are hit and we need to
   * return global handle
   */
  if (ll_handle != SESSION_INVALID_HANDLE)
    {
      local_session_t *ll;
      stream_session_t *tl;
      ll = application_get_local_listener_w_handle (ll_handle);
      tl = listen_session_get_from_handle (*handle);
      ll->transport_listener_index = tl->session_index;
    }
  return rv;
}

int
vnet_unbind_i (u32 app_index, session_handle_t handle)
{
  application_t *app;
  int rv;

  if (!(app = application_get_if_valid (app_index)))
    {
      SESSION_DBG ("app (%d) not attached", app_index);
      return VNET_API_ERROR_APPLICATION_NOT_ATTACHED;
    }

  if (application_has_local_scope (app))
    {
      if ((rv = application_stop_local_listen (app, handle)))
	return rv;
    }

  /*
   * Clear the global scope table of the listener
   */
  if (application_has_global_scope (app))
    return application_stop_listen (app, handle);
  return 0;
}

int
application_connect (u32 client_index, u32 api_context,
		     session_endpoint_t * sep)
{
  application_t *server, *client;
  u32 table_index, server_index, li;
  stream_session_t *listener;
  local_session_t *ll;
  u64 lh;

  if (session_endpoint_is_zero (sep))
    return VNET_API_ERROR_INVALID_VALUE;

  client = application_get (client_index);
  session_endpoint_update_for_app (sep, client);

  /*
   * First check the local scope for locally attached destinations.
   * If we have local scope, we pass *all* connects through it since we may
   * have special policy rules even for non-local destinations, think proxy.
   */
  if (application_has_local_scope (client))
    {
      table_index = application_local_session_table (client);
      lh = session_lookup_local_endpoint (table_index, sep);
      if (lh == SESSION_DROP_HANDLE)
	return VNET_API_ERROR_APP_CONNECT_FILTERED;

      if (lh == SESSION_INVALID_HANDLE)
	
@media only all and (prefers-color-scheme: dark) {
.highlight .hll { background-color: #49483e }
.highlight .c { color: #75715e } /* Comment */
.highlight .err { color: #960050; background-color: #1e0010 } /* Error */
.highlight .k { color: #66d9ef } /* Keyword */
.highlight .l { color: #ae81ff } /* Literal */
.highlight .n { color: #f8f8f2 } /* Name */
.highlight .o { color: #f92672 } /* Operator */
.highlight .p { color: #f8f8f2 } /* Punctuation */
.highlight .ch { color: #75715e } /* Comment.Hashbang */
.highlight .cm { color: #75715e } /* Comment.Multiline */
.highlight .cp { color: #75715e } /* Comment.Preproc */
.highlight .cpf { color: #75715e } /* Comment.PreprocFile */
.highlight .c1 { color: #75715e } /* Comment.Single */
.highlight .cs { color: #75715e } /* Comment.Special */
.highlight .gd { color: #f92672 } /* Generic.Deleted */
.highlight .ge { font-style: italic } /* Generic.Emph */
.highlight .gi { color: #a6e22e } /* Generic.Inserted */
.highlight .gs { font-weight: bold } /* Generic.Strong */
.highlight .gu { color: #75715e } /* Generic.Subheading */
.highlight .kc { color: #66d9ef } /* Keyword.Constant */
.highlight .kd { color: #66d9ef } /* Keyword.Declaration */
.highlight .kn { color: #f92672 } /* Keyword.Namespace */
.highlight .kp { color: #66d9ef } /* Keyword.Pseudo */
.highlight .kr { color: #66d9ef } /* Keyword.Reserved */
.highlight .kt { color: #66d9ef } /* Keyword.Type */
.highlight .ld { color: #e6db74 } /* Literal.Date */
.highlight .m { color: #ae81ff } /* Literal.Number */
.highlight .s { color: #e6db74 } /* Literal.String */
.highlight .na { color: #a6e22e } /* Name.Attribute */
.highlight .nb { color: #f8f8f2 } /* Name.Builtin */
.highlight .nc { color: #a6e22e } /* Name.Class */
.highlight .no { color: #66d9ef } /* Name.Constant */
.highlight .nd { color: #a6e22e } /* Name.Decorator */
.highlight .ni { color: #f8f8f2 } /* Name.Entity */
.highlight .ne { color: #a6e22e } /* Name.Exception */
.highlight .nf { color: #a6e22e } /* Name.Function */
.highlight .nl { color: #f8f8f2 } /* Name.Label */
.highlight .nn { color: #f8f8f2 } /* Name.Namespace */
.highlight .nx { color: #a6e22e } /* Name.Other */
.highlight .py { color: #f8f8f2 } /* Name.Property */
.highlight .nt { color: #f92672 } /* Name.Tag */
.highlight .nv { color: #f8f8f2 } /* Name.Variable */
.highlight .ow { color: #f92672 } /* Operator.Word */
.highlight .w { color: #f8f8f2 } /* Text.Whitespace */
.highlight .mb { color: #ae81ff } /* Literal.Number.Bin */
.highlight .mf { color: #ae81ff } /* Literal.Number.Float */
.highlight .mh { color: #ae81ff } /* Literal.Number.Hex */
.highlight .mi { color: #ae81ff } /* Literal.Number.Integer */
.highlight .mo { color: #ae81ff } /* Literal.Number.Oct */
.highlight .sa { color: #e6db74 } /* Literal.String.Affix */
.highlight .sb { color: #e6db74 } /* Literal.String.Backtick */
.highlight .sc { color: #e6db74 } /* Literal.String.Char */
.highlight .dl { color: #e6db74 } /* Literal.String.Delimiter */
.highlight .sd { color: #e6db74 } /* Literal.String.Doc */
.highlight .s2 { color: #e6db74 } /* Literal.String.Double */
.highlight .se { color: #ae81ff } /* Literal.String.Escape */
.highlight .sh { color: #e6db74 } /* Literal.String.Heredoc */
.highlight .si { color: #e6db74 } /* Literal.String.Interpol */
.highlight .sx { color: #e6db74 } /* Literal.String.Other */
.highlight .sr { color: #e6db74 } /* Literal.String.Regex */
.highlight .s1 { color: #e6db74 } /* Literal.String.Single */
.highlight .ss { color: #e6db74 } /* Literal.String.Symbol */
.highlight .bp { color: #f8f8f2 } /* Name.Builtin.Pseudo */
.highlight .fm { color: #a6e22e } /* Name.Function.Magic */
.highlight .vc { color: #f8f8f2 } /* Name.Variable.Class */
.highlight .vg { color: #f8f8f2 } /* Name.Variable.Global */
.highlight .vi { color: #f8f8f2 } /* Name.Variable.Instance */
.highlight .vm { color: #f8f8f2 } /* Name.Variable.Magic */
.highlight .il { color: #ae81ff } /* Literal.Number.Integer.Long */
}
@media (prefers-color-scheme: light) {
.highlight .hll { background-color: #ffffcc }
.highlight .c { color: #888888 } /* Comment */
.highlight .err { color: #a61717; background-color: #e3d2d2 } /* Error */
.highlight .k { color: #008800; font-weight: bold } /* Keyword */
.highlight .ch { color: #888888 } /* Comment.Hashbang */
.highlight .cm { color: #888888 } /* Comment.Multiline */
.highlight .cp { color: #cc0000; font-weight: bold } /* Comment.Preproc */
.highlight .cpf { color: #888888 } /* Comment.PreprocFile */
.highlight .c1 { color: #888888 } /* Comment.Single */
.highlight .cs { color: #cc0000; font-weight: bold; background-color: #fff0f0 } /* Comment.Special */
.highlight .gd { color: #000000; background-color: #ffdddd } /* Generic.Deleted */
.highlight .ge { font-style: italic } /* Generic.Emph */
.highlight .gr { color: #aa0000 } /* Generic.Error */
.highlight .gh { color: #333333 } /* Generic.Heading */
.highlight .gi { color: #000000; background-color: #ddffdd } /* Generic.Inserted */
.highlight .go { color: #888888 } /* Generic.Output */
.highlight .gp { color: #555555 } /* Generic.Prompt */
.highlight .gs { font-weight: bold } /* Generic.Strong */
.highlight .gu { color: #666666 } /* Generic.Subheading */
.highlight .gt { color: #aa0000 } /* Generic.Traceback */
.highlight .kc { color: #008800; font-weight: bold } /* Keyword.Constant */
.highlight .kd { color: #008800; font-weight: bold } /* Keyword.Declaration */
.highlight .kn { color: #008800; font-weight: bold } /* Keyword.Namespace */
.highlight .kp { color: #008800 } /* Keyword.Pseudo */
.highlight .kr { color: #008800; font-weight: bold } /* Keyword.Reserved */
.highlight .kt { color: #888888; font-weight: bold } /* Keyword.Type */
.highlight .m { color: #0000DD; font-weight: bold } /* Literal.Number */
.highlight .s { color: #dd2200; background-color: #fff0f0 } /* Literal.String */
.highlight .na { color: #336699 } /* Name.Attribute */
.highlight .nb { color: #003388 } /* Name.Builtin */
.highlight .nc { color: #bb0066; font-weight: bold } /* Name.Class */
.highlight .no { color: #003366; font-weight: bold } /* Name.Constant */
.highlight .nd { color: #555555 } /* Name.Decorator */
.highlight .ne { color: #bb0066; font-weight: bold } /* Name.Exception */
.highlight .nf { color: #0066bb; font-weight: bold } /* Name.Function */
.highlight .nl { color: #336699; font-style: italic } /* Name.Label */
.highlight .nn { color: #bb0066; font-weight: bold } /* Name.Namespace */
.highlight .py { color: #336699; font-weight: bold } /* Name.Property */
.highlight .nt { color: #bb0066; font-weight: bold } /* Name.Tag */
.highlight .nv { color: #336699 } /* Name.Variable */
.highlight .ow { color: #008800 } /* Operator.Word */
.highlight .w { color: #bbbbbb } /* Text.Whitespace */
.highlight .mb { color: #0000DD; font-weight: bold } /* Literal.Number.Bin */
.highlight .mf { color: #0000DD; font-weight: bold } /* Literal.Number.Float */
.highlight .mh { color: #0000DD; font-weight: bold } /* Literal.Number.Hex */
.highlight .mi { color: #0000DD; font-weight: bold } /* Literal.Number.Integer */
.highlight .mo { color: #0000DD; font-weight: bold } /* Literal.Number.Oct */
.highlight .sa { color: #dd2200; background-color: #fff0f0 } /* Literal.String.Affix */
.highlight .sb { color: #dd2200; background-color: #fff0f0 } /* Literal.String.Backtick */
.highlight .sc { color: #dd2200; background-color: #fff0f0 } /* Literal.String.Char */
.highlight .dl { color: #dd2200; background-color: #fff0f0 } /* Literal.String.Delimiter */
.highlight .sd { color: #dd2200; background-color: #fff0f0 } /* Literal.String.Doc */
.highlight .s2 { color: #dd2200; background-color: #fff0f0 } /* Literal.String.Double */
.highlight .se { color: #0044dd; background-color: #fff0f0 } /* Literal.String.Escape */
.highlight .sh { color: #dd2200; background-color: #fff0f0 } /* Literal.String.Heredoc */
.highlight .si { color: #3333bb; background-color: #fff0f0 } /* Literal.String.Interpol */
.highlight .sx { color: #22bb22; background-color: #f0fff0 } /* Literal.String.Other */
.highlight .sr { color: #008800; background-color: #fff0ff } /* Literal.String.Regex */
.highlight .s1 { color: #dd2200; background-color: #fff0f0 } /* Literal.String.Single */
.highlight .ss { color: #aa6600; background-color: #fff0f0 } /* Literal.String.Symbol */
.highlight .bp { color: #003388 } /* Name.Builtin.Pseudo */
.highlight .fm { color: #0066bb; font-weight: bold } /* Name.Function.Magic */
.highlight .vc { color: #336699 } /* Name.Variable.Class */
.highlight .vg { color: #dd7700 } /* Name.Variable.Global */
.highlight .vi { color: #3333bb } /* Name.Variable.Instance */
.highlight .vm { color: #336699 } /* Name.Variable.Magic */
.highlight .il { color: #0000DD; font-weight: bold } /* Literal.Number.Integer.Long */
}
/*
 * 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 <vlib/vlib.h>
#include <vnet/ip/format.h>
#include <vnet/ip/lookup.h>
#include <vnet/adj/adj.h>
#include <vnet/dpo/load_balance.h>
#include <vnet/dpo/drop_dpo.h>

#include <vnet/fib/fib_entry.h>
#include <vnet/fib/fib_walk.h>
#include <vnet/fib/fib_entry_src.h>
#include <vnet/fib/fib_entry_cover.h>
#include <vnet/fib/fib_table.h>
#include <vnet/fib/fib_internal.h>
#include <vnet/fib/fib_attached_export.h>
#include <vnet/fib/fib_path_ext.h>
#include <vnet/fib/fib_entry_delegate.h>
#include <vnet/fib/fib_entry_track.h>

/*
 * Array of strings/names for the FIB sources
 */
static const char *fib_source_names[] = FIB_SOURCES;
static const char *fib_attribute_names[] = FIB_ENTRY_ATTRIBUTES;
static const char *fib_src_attribute_names[] = FIB_ENTRY_SRC_ATTRIBUTES;

/*
 * Pool for all fib_entries
 */
static fib_entry_t *fib_entry_pool;

/**
 * the logger
 */
vlib_log_class_t fib_entry_logger;

fib_entry_t *
fib_entry_get (fib_node_index_t index)
{
    return (pool_elt_at_index(fib_entry_pool, index));
}

static fib_node_t *
fib_entry_get_node (fib_node_index_t index)
{
    return ((fib_node_t*)fib_entry_get(index));
}

fib_node_index_t
fib_entry_get_index (const fib_entry_t * fib_entry)
{
    return (fib_entry - fib_entry_pool);
}

fib_protocol_t
fib_entry_get_proto (const fib_entry_t * fib_entry)
{
    return (fib_entry->fe_prefix.fp_proto);
}

dpo_proto_t
fib_entry_get_dpo_proto (const fib_entry_t * fib_entry)
{
    return (fib_proto_to_dpo(fib_entry->fe_prefix.fp_proto));
}

fib_forward_chain_type_t
fib_entry_get_default_chain_type (const fib_entry_t *fib_entry)
{
    switch (fib_entry->fe_prefix.fp_proto)
    {
    case FIB_PROTOCOL_IP4:
	return (FIB_FORW_CHAIN_TYPE_UNICAST_IP4);
    case FIB_PROTOCOL_IP6:
	return (FIB_FORW_CHAIN_TYPE_UNICAST_IP6);
    case FIB_PROTOCOL_MPLS:
	if (MPLS_EOS == fib_entry->fe_prefix.fp_eos)
	    return (FIB_FORW_CHAIN_TYPE_MPLS_EOS);
	else
	    return (FIB_FORW_CHAIN_TYPE_MPLS_NON_EOS);
    }

    return (FIB_FORW_CHAIN_TYPE_UNICAST_IP4);
}

u8 *
format_fib_source (u8 * s, va_list * args)
{
    fib_source_t source = va_arg (*args, int);

    s = format (s, "src:%s", fib_source_names[source]);

    return (s);
}

u8 *
format_fib_entry_flags (u8 *s, va_list *args)
{
    fib_entry_attribute_t attr;
    fib_entry_flag_t flag = va_arg(*args, int);

    FOR_EACH_FIB_ATTRIBUTE(attr) {
        if ((1<<attr) & flag) {
            s = format (s, "%s,", fib_attribute_names[attr]);
        }
    }

    return (s);
}

u8 *
format_fib_entry_src_flags (u8 *s, va_list *args)
{
    fib_entry_src_attribute_t sattr;
    fib_entry_src_flag_t flag = va_arg(*args, int);

    FOR_EACH_FIB_SRC_ATTRIBUTE(sattr) {
        if ((1<<sattr) & flag) {
            s = format (s, "%s,", fib_src_attribute_names[sattr]);
        }
    }

    return (s);
}

u8 *
format_fib_entry (u8 * s, va_list * args)
{
    fib_forward_chain_type_t fct;
    fib_entry_t *fib_entry;
    fib_entry_src_t *src;
    fib_node_index_t fei;
    fib_source_t source;
    int level;

    fei = va_arg (*args, fib_node_index_t);
    level = va_arg (*args, int);
    fib_entry = fib_entry_get(fei);

    s = format (s, "%U", format_fib_prefix, &fib_entry->fe_prefix);

    if (level >= FIB_ENTRY_FORMAT_DETAIL)
    {
	s = format (s, " fib:%d", fib_entry->fe_fib_index);
	s = format (s, " index:%d", fib_entry_get_index(fib_entry));
	s = format (s, " locks:%d", fib_entry->fe_node.fn_locks);

	FOR_EACH_SRC_ADDED(fib_entry, src, source,
        ({
	    s = format (s, "\n  %U", format_fib_source, source);
	    s = format (s, " refs:%d", src->fes_ref_count);
	    if (FIB_ENTRY_FLAG_NONE != src->fes_entry_flags) {
		s = format(s, " entry-flags:%U",
                           format_fib_entry_flags, src->fes_entry_flags);
	    }
	    if (FIB_ENTRY_SRC_FLAG_NONE != src->fes_flags) {
		s = format(s, " src-flags:%U",
                           format_fib_entry_src_flags, src->fes_flags);
	    }
            s = fib_entry_src_format(fib_entry, source, s);
	    s = format (s, "\n");
	    if (FIB_NODE_INDEX_INVALID != src->fes_pl)
	    {
		s = fib_path_list_format(src->fes_pl, s);
	    }
            s = format(s, "%U", format_fib_path_ext_list, &src->fes_path_exts);
	}));
    
	s = format (s, "\n forwarding: ");
    }
    else
    {
	s = format (s, "\n");
    }

    fct = fib_entry_get_default_chain_type(fib_entry);

    if (!dpo_id_is_valid(&fib_entry->fe_lb))
    {
	s = format (s, "  UNRESOLVED\n");
	return (s);
    }
    else
    {
        s = format(s, "  %U-chain\n  %U",
                   format_fib_forw_chain_type, fct,
                   format_dpo_id,
                   &fib_entry->fe_lb,
                   2);
        s = format(s, "\n");

        if (level >= FIB_ENTRY_FORMAT_DETAIL2)
        {
            index_t *fedi;

            s = format (s, " Delegates:\n");
            vec_foreach(fedi, fib_entry->fe_delegates)
            {
                s = format(s, "  %U\n", format_fib_entry_delegate, *fedi);
            }
        }
    }

    if (level >= FIB_ENTRY_FORMAT_DETAIL2)
    {
        s = format(s, " Children:");
        s = fib_node_children_format(fib_entry->fe_node.fn_children, s);
    }

    return (s);
}

static fib_entry_t*
fib_entry_from_fib_node (fib_node_t *node)
{
    ASSERT(FIB_NODE_TYPE_ENTRY == node->fn_type);
    return ((fib_entry_t*)node);
}

static void
fib_entry_last_lock_gone (fib_node_t *node)
{
    fib_entry_delegate_type_t fdt;
    fib_entry_delegate_t *fed;
    fib_entry_t *fib_entry;

    fib_entry = fib_entry_from_fib_node(node);

    ASSERT(!dpo_id_is_valid(&fib_entry->fe_lb));

    FOR_EACH_DELEGATE_CHAIN(fib_entry, fdt, fed,
    {
	dpo_reset(&fed->fd_dpo);
        fib_entry_delegate_remove(fib_entry, fdt);
    });

    FIB_ENTRY_DBG(fib_entry, "last-lock");

    fib_node_deinit(&fib_entry->fe_node);

    ASSERT(0 == vec_len(fib_entry->fe_delegates));
    vec_free(fib_entry->fe_delegates);
    vec_free(fib_entry->fe_srcs);
    pool_put(fib_entry_pool, fib_entry);
}

static fib_entry_src_t*
fib_entry_get_best_src_i (const fib_entry_t *fib_entry)
{
    fib_entry_src_t *bsrc;

    /*
     * the enum of sources is deliberately arranged in priority order
     */
    if (0 == vec_len(fib_entry->fe_srcs))
    {
	bsrc = NULL;
    }
    else
    {
	bsrc = vec_elt_at_index(fib_entry->fe_srcs, 0);
    }

    return (bsrc);
}

static fib_source_t
fib_entry_src_get_source (const fib_entry_src_t *esrc)
{
    if (NULL != esrc)
    {
	return (esrc->fes_src);
    }
    return (FIB_SOURCE_MAX);
}

static fib_entry_flag_t
fib_entry_src_get_flags (const fib_entry_src_t *esrc)
{
    if (NULL != esrc)
    {
	return (esrc->fes_entry_flags);
    }
    return (FIB_ENTRY_FLAG_NONE);
}

fib_entry_flag_t
fib_entry_get_flags (fib_node_index_t fib_entry_index)
{
    return (fib_entry_get_flags_i(fib_entry_get(fib_entry_index)));
}

/*
 * fib_entry_back_walk_notify
 *
 * A back walk has reach this entry.
 */
static fib_node_back_walk_rc_t
fib_entry_back_walk_notify (fib_node_t *node,
			    fib_node_back_walk_ctx_t *ctx)
{
    fib_entry_t *fib_entry;

    fib_entry = fib_entry_from_fib_node(node);

    if (FIB_NODE_BW_REASON_FLAG_EVALUATE & ctx->fnbw_reason        ||
        FIB_NODE_BW_REASON_FLAG_ADJ_UPDATE & ctx->fnbw_reason      ||
        FIB_NODE_BW_REASON_FLAG_ADJ_DOWN & ctx->fnbw_reason        ||
	FIB_NODE_BW_REASON_FLAG_INTERFACE_UP & ctx->fnbw_reason    ||
	FIB_NODE_BW_REASON_FLAG_INTERFACE_DOWN & ctx->fnbw_reason  ||
	FIB_NODE_BW_REASON_FLAG_INTERFACE_DELETE & ctx->fnbw_reason)
    {
	fib_entry_src_action_reactivate(fib_entry,
                                        fib_entry_get_best_source(
                                            fib_entry_get_index(fib_entry)));
    }

    /*
     * all other walk types can be reclassifed to a re-evaluate to
     * all recursive dependents.
     * By reclassifying we ensure that should any of these walk types meet
     * they can be merged.
     */
    ctx->fnbw_reason = FIB_NODE_BW_REASON_FLAG_EVALUATE;

    /*
     * ... and nothing is forced sync from now on.
     */
    ctx->fnbw_flags &= ~FIB_NODE_BW_FLAG_FORCE_SYNC;

    FIB_ENTRY_DBG(fib_entry, "bw:%U",
                  format_fib_node_bw_reason, ctx->fnbw_reason);

    /*
     * propagate the backwalk further if we haven't already reached the
     * maximum depth.
     */
    fib_walk_sync(FIB_NODE_TYPE_ENTRY,
		  fib_entry_get_index(fib_entry),
		  ctx);

    return (FIB_NODE_BACK_WALK_CONTINUE);
}

static void
fib_entry_show_memory (void)
{
    u32 n_srcs = 0, n_exts = 0;
    fib_entry_src_t *esrc;
    fib_entry_t *entry;

    fib_show_memory_usage("Entry",
			  pool_elts(fib_entry_pool),
			  pool_len(fib_entry_pool),
			  sizeof(fib_entry_t));

    pool_foreach(entry, fib_entry_pool,
    ({
	n_srcs += vec_len(entry->fe_srcs);
	vec_foreach(esrc, entry->fe_srcs)
	{
	    n_exts += fib_path_ext_list_length(&esrc->fes_path_exts);
	}
    }));

    fib_show_memory_usage("Entry Source",
			  n_srcs, n_srcs, sizeof(fib_entry_src_t));
    fib_show_memory_usage("Entry Path-Extensions",
			  n_exts, n_exts,
			  sizeof(fib_path_ext_t));
}

/*
 * The FIB path-list's graph node virtual function table
 */
static const fib_node_vft_t fib_entry_vft = {
    .fnv_get = fib_entry_get_node,
    .fnv_last_lock = fib_entry_last_lock_gone,
    .fnv_back_walk = fib_entry_back_walk_notify,
    .fnv_mem_show = fib_entry_show_memory,
};

/**
 * @brief Contribute the set of Adjacencies that this entry forwards with
 * to build the uRPF list of its children
 */
void
fib_entry_contribute_urpf (fib_node_index_t entry_index,
			   index_t urpf)
{
    fib_entry_t *fib_entry;

    fib_entry = fib_entry_get(entry_index);

    return (fib_path_list_contribute_urpf(fib_entry->fe_parent, urpf));
}

/*
 * If the client is request a chain for multicast forwarding then swap
 * the chain type to one that can provide such transport.
 */
static fib_forward_chain_type_t
fib_entry_chain_type_mcast_to_ucast (fib_forward_chain_type_t fct)
{
    switch (fct)
    {
    case FIB_FORW_CHAIN_TYPE_MCAST_IP4:
    case FIB_FORW_CHAIN_TYPE_MCAST_IP6:
        /*
         * we can only transport IP multicast packets if there is an
         * LSP.
         */
        fct = FIB_FORW_CHAIN_TYPE_MPLS_EOS;
        break;
    case FIB_FORW_CHAIN_TYPE_MPLS_EOS:
    case FIB_FORW_CHAIN_TYPE_UNICAST_IP4:
    case FIB_FORW_CHAIN_TYPE_UNICAST_IP6:
    case FIB_FORW_CHAIN_TYPE_MPLS_NON_EOS:
    case FIB_FORW_CHAIN_TYPE_ETHERNET:
    case FIB_FORW_CHAIN_TYPE_NSH:
    case FIB_FORW_CHAIN_TYPE_BIER:
        break;
    }

    return (fct);
}

/*
 * fib_entry_contribute_forwarding
 *
 * Get an lock the forwarding information (DPO) contributed by the FIB entry.
 */
void
fib_entry_contribute_forwarding (fib_node_index_t fib_entry_index,
				 fib_forward_chain_type_t fct,
				 dpo_id_t *dpo)
{
    fib_entry_delegate_t *fed;
    fib_entry_t *fib_entry;

    fib_entry = fib_entry_get(fib_entry_index);

    /*
     * mfib children ask for mcast chains. fix these to the appropriate ucast types.
     */
    fct = fib_entry_chain_type_mcast_to_ucast(fct);

    if (fct == fib_entry_get_default_chain_type(fib_entry))
    {
        dpo_copy(dpo, &fib_entry->fe_lb);
    }
    else
    {
        fed = fib_entry_delegate_find(fib_entry,
                                      fib_entry_chain_type_to_delegate_type(fct));

        if (NULL == fed)
        {
            fed = fib_entry_delegate_find_or_add(
                      fib_entry,
                      fib_entry_chain_type_to_delegate_type(fct));
            /*
             * on-demand create eos/non-eos.
             * There is no on-demand delete because:
             *   - memory versus complexity & reliability:
             *      leaving unrequired [n]eos LB arounds wastes memory, cleaning
             *      then up on the right trigger is more code. i favour the latter.
             */
            fib_entry_src_mk_lb(fib_entry,
                                fib_entry_get_best_src_i(fib_entry),
                                fct,
                                &fed->fd_dpo);
        }

        dpo_copy(dpo, &fed->fd_dpo);
    }
    /*
     * use the drop DPO is nothing else is present
     */
    if (!dpo_id_is_valid(dpo))
    {
        dpo_copy(dpo, drop_dpo_get(fib_forw_chain_type_to_dpo_proto(fct)));
    }

    /*
     * don't allow the special index indicating replicate.vs.load-balance
     * to escape to the clients
     */
    dpo->dpoi_index &= ~MPLS_IS_REPLICATE;
}

const dpo_id_t *
fib_entry_contribute_ip_forwarding (fib_node_index_t fib_entry_index)
{
    fib_forward_chain_type_t fct;
    fib_entry_t *fib_entry;

    fib_entry = fib_entry_get(fib_entry_index);
    fct = fib_entry_get_default_chain_type(fib_entry);

    ASSERT((fct == FIB_FORW_CHAIN_TYPE_UNICAST_IP4 ||
            fct == FIB_FORW_CHAIN_TYPE_UNICAST_IP6));

    if (dpo_id_is_valid(&fib_entry->fe_lb))
    {
        return (&fib_entry->fe_lb);
    }

    return (drop_dpo_get(fib_forw_chain_type_to_dpo_proto(fct)));
}

adj_index_t
fib_entry_get_adj (fib_node_index_t fib_entry_index)
{
    const dpo_id_t *dpo;

    dpo = fib_entry_contribute_ip_forwarding(fib_entry_index);

    if (dpo_id_is_valid(dpo))
    {
        dpo = load_balance_get_bucket(dpo->dpoi_index, 0);

        if (dpo_is_adj(dpo))
        {
            return (dpo->dpoi_index);
        }
    }
    return (ADJ_INDEX_INVALID);
}

fib_node_index_t
fib_entry_get_path_list (fib_node_index_t fib_entry_index)
{
    fib_entry_t *fib_entry;

    fib_entry = fib_entry_get(fib_entry_index);

    return (fib_entry->fe_parent);
}

u32
fib_entry_child_add (fib_node_index_t fib_entry_index,
		     fib_node_type_t child_type,
		     fib_node_index_t child_index)
{
    return (fib_node_child_add(FIB_NODE_TYPE_ENTRY,
                               fib_entry_index,
                               child_type,
                               child_index));
};

void
fib_entry_child_remove (fib_node_index_t fib_entry_index,
			u32 sibling_index)
{
    fib_node_child_remove(FIB_NODE_TYPE_ENTRY,
                          fib_entry_index,
                          sibling_index);

    if (0 == fib_node_get_n_children(FIB_NODE_TYPE_ENTRY,
                                     fib_entry_index))
    {
        /*
         * if there are no children left then there is no reason to keep
         * the non-default forwarding chains. those chains are built only
         * because the children want them.
         */
        fib_entry_delegate_type_t fdt;
        fib_entry_delegate_t *fed;
        fib_entry_t *fib_entry;

        fib_entry = fib_entry_get(fib_entry_index);

        FOR_EACH_DELEGATE_CHAIN(fib_entry, fdt, fed,
        {
            dpo_reset(&fed->fd_dpo);
            fib_entry_delegate_remove(fib_entry, fdt);
        });
    }
}

static fib_entry_t *
fib_entry_alloc (u32 fib_index,
		 const fib_prefix_t *prefix,
		 fib_node_index_t *fib_entry_index)
{
    fib_entry_t *fib_entry;
    fib_prefix_t *fep;

    pool_get(fib_entry_pool, fib_entry);
    clib_memset(fib_entry, 0, sizeof(*fib_entry));

    fib_node_init(&fib_entry->fe_node,
		  FIB_NODE_TYPE_ENTRY);

    fib_entry->fe_fib_index = fib_index;

    /*
     * the one time we need to update the const prefix is when
     * the entry is first created
     */
    fep = (fib_prefix_t*)&(fib_entry->fe_prefix);
    *fep = *prefix;

    if (FIB_PROTOCOL_MPLS == fib_entry->fe_prefix.fp_proto)
    {
	fep->fp_len = 21;
	if (MPLS_NON_EOS == fep->fp_eos)
	{
	    fep->fp_payload_proto = DPO_PROTO_MPLS;
	}
    	ASSERT(DPO_PROTO_NONE != fib_entry->fe_prefix.fp_payload_proto);
    }

    dpo_reset(&fib_entry->fe_lb);

    *fib_entry_index = fib_entry_get_index(fib_entry);

    return (fib_entry);
}

static fib_entry_t*
fib_entry_post_flag_update_actions (fib_entry_t *fib_entry,
				    fib_entry_flag_t old_flags)
{
    fib_node_index_t fei;

    /*
     * save the index so we can recover from pool reallocs
     */
    fei = fib_entry_get_index(fib_entry);

    /*
     * handle changes to attached export for import entries
     */
    int is_import  = (FIB_ENTRY_FLAG_IMPORT & fib_entry_get_flags_i(fib_entry));
    int was_import = (FIB_ENTRY_FLAG_IMPORT & old_flags);

    if (!was_import && is_import)
    {
	/*
	 * transition from not exported to exported
	 */

	/*
	 * there is an assumption here that the entry resolves via only
	 * one interface and that it is the cross VRF interface.
	 */
	u32 sw_if_index = fib_path_list_get_resolving_interface(fib_entry->fe_parent);

	fib_attached_export_import(fib_entry,
				   fib_table_get_index_for_sw_if_index(
				       fib_entry_get_proto(fib_entry),
                                       sw_if_index));
    }
    else if (was_import && !is_import)
    {
	/*
	 * transition from exported to not exported
	 */
	fib_attached_export_purge(fib_entry);
    }
    /*
     * else
     *   no change. nothing to do.
     */

    /*
     * reload the entry address post possible pool realloc
     */
    fib_entry = fib_entry_get(fei);

    /*
     * handle changes to attached export for export entries
     */
    int is_attached  = (FIB_ENTRY_FLAG_ATTACHED & fib_entry_get_flags_i(fib_entry));
    int was_attached = (FIB_ENTRY_FLAG_ATTACHED & old_flags);

    if (!was_attached && is_attached)
    {
	/*
	 * transition to attached. time to export
	 */
	// FIXME
    }
    // else FIXME

    return (fib_entry);
}

static void
fib_entry_post_install_actions (fib_entry_t *fib_entry,
				fib_source_t source,
				fib_entry_flag_t old_flags)
{
    fib_entry = fib_entry_post_flag_update_actions(fib_entry,
                                                   old_flags);
    fib_entry_src_action_installed(fib_entry, source);
}

fib_node_index_t
fib_entry_create (u32 fib_index,
		  const fib_prefix_t *prefix,
		  fib_source_t source,
		  fib_entry_flag_t flags,
		  const fib_route_path_t *paths)
{
    fib_node_index_t fib_entry_index;
    fib_entry_t *fib_entry;

    ASSERT(0 < vec_len(paths));

    fib_entry = fib_entry_alloc(fib_index, prefix, &fib_entry_index);

    /*
     * since this is a new entry create, we don't need to check for winning
     * sources - there is only one.
     */
    fib_entry = fib_entry_src_action_add(fib_entry, source, flags,
                                         drop_dpo_get(
                                             fib_proto_to_dpo(
                                                 fib_entry_get_proto(fib_entry))));
    fib_entry_src_action_path_swap(fib_entry,
				   source,
				   flags,
				   paths);
    /*
     * handle possible realloc's by refetching the pointer
     */
    fib_entry = fib_entry_get(fib_entry_index);
    fib_entry_src_action_activate(fib_entry, source);

    fib_entry_post_install_actions(fib_entry, source, FIB_ENTRY_FLAG_NONE);

    FIB_ENTRY_DBG(fib_entry, "create");

    return (fib_entry_index);
}

fib_node_index_t
fib_entry_create_special (u32 fib_index,
			  const fib_prefix_t *prefix,
			  fib_source_t source,
			  fib_entry_flag_t flags,
			  const dpo_id_t *dpo)
{
    fib_node_index_t fib_entry_index;
    fib_entry_t *fib_entry;

    /*
     * create and initialize the new enty
     */
    fib_entry = fib_entry_alloc(fib_index, prefix, &fib_entry_index);

    /*
     * create the path-list
     */
    fib_entry = fib_entry_src_action_add(fib_entry, source, flags, dpo);
    fib_entry_src_action_activate(fib_entry, source);

    fib_entry_post_install_actions(fib_entry, source, FIB_ENTRY_FLAG_NONE);

    FIB_ENTRY_DBG(fib_entry, "create-special");

    return (fib_entry_index);
}

static void
fib_entry_post_update_actions (fib_entry_t *fib_entry,
			       fib_source_t source,
			       fib_entry_flag_t old_flags)
{
    /*
     * backwalk to children to inform then of the change to forwarding.
     */
    fib_node_back_walk_ctx_t bw_ctx = {
	.fnbw_reason = FIB_NODE_BW_REASON_FLAG_EVALUATE,
    };

    fib_walk_sync(FIB_NODE_TYPE_ENTRY, fib_entry_get_index(fib_entry), &bw_ctx);

    /*
     * then inform any covered prefixes
     */
    fib_entry_cover_update_notify(fib_entry);

    fib_entry_post_install_actions(fib_entry, source, old_flags);
}

void
fib_entry_recalculate_forwarding (fib_node_index_t fib_entry_index)
{
    fib_source_t best_source;
    fib_entry_t *fib_entry;
    fib_entry_src_t *bsrc;

    fib_entry = fib_entry_get(fib_entry_index);

    bsrc = fib_entry_get_best_src_i(fib_entry);
    best_source = fib_entry_src_get_source(bsrc);

    fib_entry_src_action_reactivate(fib_entry, best_source);
}

static void
fib_entry_source_change_w_flags (fib_entry_t *fib_entry,
                                 fib_source_t old_source,
                                 fib_entry_flag_t old_flags,
                                 fib_source_t new_source)
{
    if (new_source < old_source)
    {
	/*
	 * we have a new winning source.
	 */
	fib_entry_src_action_deactivate(fib_entry, old_source);
	fib_entry_src_action_activate(fib_entry, new_source);
    }
    else if (new_source > old_source)
    {
        /*
         * the new source loses. Re-activate the winning sources
         * in case it is an interposer and hence relied on the losing
         * source's path-list.
         */
        fib_entry_src_action_reactivate(fib_entry, old_source);
        return;
    }
    else
    {
	/*
	 * the new source is one this entry already has.
	 * But the path-list was updated, which will contribute new forwarding,
	 * so install it.
	 */
        fib_entry_src_action_reactivate(fib_entry, new_source);
    }

    fib_entry_post_update_actions(fib_entry, new_source, old_flags);
}

void
fib_entry_source_change (fib_entry_t *fib_entry,
                         fib_source_t old_source,
			 fib_source_t new_source)
{
    fib_entry_flag_t old_flags;

    old_flags = fib_entry_get_flags_for_source(
        fib_entry_get_index(fib_entry), old_source);

    return (fib_entry_source_change_w_flags(fib_entry, old_source,
                                            old_flags, new_source));
}

void
fib_entry_special_add (fib_node_index_t fib_entry_index,
		       fib_source_t source,
		       fib_entry_flag_t flags,
		       const dpo_id_t *dpo)
{
    fib_source_t best_source;
    fib_entry_t *fib_entry;

    fib_entry = fib_entry_get(fib_entry_index);
    best_source = fib_entry_get_best_source(fib_entry_index);

    fib_entry = fib_entry_src_action_add(fib_entry, source, flags, dpo);
    fib_entry_source_change(fib_entry, best_source, source);
    FIB_ENTRY_DBG(fib_entry, "special-add:%U", format_fib_source, source);
}

void
fib_entry_special_update (fib_node_index_t fib_entry_index,
			  fib_source_t source,
			  fib_entry_flag_t flags,
			  const dpo_id_t *dpo)
{
    fib_source_t best_source;
    fib_entry_t *fib_entry;

    fib_entry = fib_entry_get(fib_entry_index);
    best_source = fib_entry_get_best_source(fib_entry_index);

    fib_entry = fib_entry_src_action_update(fib_entry, source, flags, dpo);
    fib_entry_source_change(fib_entry, best_source, source);

    FIB_ENTRY_DBG(fib_entry, "special-updated:%U", format_fib_source, source);
}


void
fib_entry_path_add (fib_node_index_t fib_entry_index,
		    fib_source_t source,
		    fib_entry_flag_t flags,
		    const fib_route_path_t *rpaths)
{
    fib_source_t best_source;
    fib_entry_t *fib_entry;
    fib_entry_src_t *bsrc;

    fib_entry = fib_entry_get(fib_entry_index);
    ASSERT(NULL != fib_entry);

    bsrc = fib_entry_get_best_src_i(fib_entry);
    best_source = fib_entry_src_get_source(bsrc);
    
    fib_entry = fib_entry_src_action_path_add(fib_entry, source, flags, rpaths);

    fib_entry_source_change(fib_entry, best_source, source);

    FIB_ENTRY_DBG(fib_entry, "path add:%U", format_fib_source, source);
}

static fib_entry_src_flag_t
fib_entry_src_burn_only_inherited (fib_entry_t *fib_entry)
{
    fib_entry_src_t *src;
    fib_source_t source;
    int has_only_inherited_sources = 1;

    FOR_EACH_SRC_ADDED(fib_entry, src, source,
    ({
        if (!(src->fes_flags & FIB_ENTRY_SRC_FLAG_INHERITED))
        {
            has_only_inherited_sources = 0;
            break;
        }
    }));
    if (has_only_inherited_sources)
    {
        FOR_EACH_SRC_ADDED(fib_entry, src, source,
        ({
            fib_entry_src_action_remove(fib_entry, source);
        }));
        return (FIB_ENTRY_SRC_FLAG_NONE);
    }
    else
    {
        return (FIB_ENTRY_SRC_FLAG_ADDED);
    }
}

static fib_entry_src_flag_t
fib_entry_source_removed (fib_entry_t *fib_entry,
                          fib_entry_flag_t old_flags)
{
    const fib_entry_src_t *bsrc;
    fib_source_t best_source;

    /*
     * if all that is left are inherited sources, then burn them
     */
    fib_entry_src_burn_only_inherited(fib_entry);

    bsrc = fib_entry_get_best_src_i(fib_entry);
    best_source = fib_entry_src_get_source(bsrc);

    if (FIB_SOURCE_MAX == best_source)
    {
        /*
         * no more sources left. this entry is toast.
         */
        fib_entry = fib_entry_post_flag_update_actions(fib_entry, old_flags);
        fib_entry_src_action_uninstall(fib_entry);

        return (FIB_ENTRY_SRC_FLAG_NONE);
    }
    else
    {
        fib_entry_src_action_activate(fib_entry, best_source);
    }

    fib_entry_post_update_actions(fib_entry, best_source, old_flags);

    /*
     * still have sources
     */
    return (FIB_ENTRY_SRC_FLAG_ADDED);
}

/*
 * fib_entry_path_remove
 *
 * remove a path from the entry.
 * return the fib_entry's index if it is still present, INVALID otherwise.
 */
fib_entry_src_flag_t
fib_entry_path_remove (fib_node_index_t fib_entry_index,
		       fib_source_t source,
		       const fib_route_path_t *rpaths)
{
    fib_entry_src_flag_t sflag;
    fib_source_t best_source;
    fib_entry_flag_t bflags;
    fib_entry_t *fib_entry;
    fib_entry_src_t *bsrc;

    fib_entry = fib_entry_get(fib_entry_index);
    ASSERT(NULL != fib_entry);

    bsrc = fib_entry_get_best_src_i(fib_entry);
    best_source = fib_entry_src_get_source(bsrc);
    bflags = fib_entry_src_get_flags(bsrc);

    sflag = fib_entry_src_action_path_remove(fib_entry, source, rpaths);

    FIB_ENTRY_DBG(fib_entry, "path remove:%U", format_fib_source, source);

    /*
     * if the path list for the source passed is invalid,
     * then we need to create a new one. else we are updating
     * an existing.
     */
    if (source < best_source)
    {
	/*
	 * Que! removing a path from a source that is better than the
	 * one this entry is using.
	 */
	ASSERT(0);
    }
    else if (source > best_source )
    {
	/*
	 * the source is not the best. no need to update forwarding
	 */
	if (FIB_ENTRY_SRC_FLAG_ADDED & sflag)
        {
            /*
             * the source being removed still has paths
             */
            return (FIB_ENTRY_SRC_FLAG_ADDED);
        }
        else
        {
            /*
             * that was the last path from this source, check if those
             * that remain are non-inherited
             */
            return (fib_entry_src_burn_only_inherited(fib_entry));
       }
    }
    else
    {
	/*
	 * removing a path from the path-list we were using.
	 */
	if (!(FIB_ENTRY_SRC_FLAG_ADDED & sflag))
	{
	    /*
	     * the last path from the source was removed.
	     * fallback to lower source
	     */
            return (fib_entry_source_removed(fib_entry, bflags));
	}
	else
	{
	    /*
	     * re-install the new forwarding information
	     */
	    fib_entry_src_action_reactivate(fib_entry, source);
	}
    }

    fib_entry_post_update_actions(fib_entry, source, bflags);

    /*
     * still have sources
     */
    return (FIB_ENTRY_SRC_FLAG_ADDED);
}

/*
 * fib_entry_special_remove
 *
 * remove a special source from the entry.
 * return the fib_entry's index if it is still present, INVALID otherwise.
 */
fib_entry_src_flag_t
fib_entry_special_remove (fib_node_index_t fib_entry_index,
			  fib_source_t source)
{
    fib_entry_src_flag_t sflag;
    fib_source_t best_source;
    fib_entry_flag_t bflags;
    fib_entry_t *fib_entry;
    fib_entry_src_t *bsrc;

    fib_entry = fib_entry_get(fib_entry_index);
    ASSERT(NULL != fib_entry);

    bsrc = fib_entry_get_best_src_i(fib_entry);
    best_source = fib_entry_src_get_source(bsrc);
    bflags = fib_entry_src_get_flags(bsrc);

    FIB_ENTRY_DBG(fib_entry, "special remove:%U", format_fib_source, source);

    sflag = fib_entry_src_action_remove_or_update_inherit(fib_entry, source);

    /*
     * if the path list for the source passed is invalid,
     * then we need to create a new one. else we are updating
     * an existing.
     */
    if (source < best_source )
    {
	/*
	 * Que! removing a path from a source that is better than the
	 * one this entry is using. This can only mean it is a source
         * this prefix does not have.
	 */
        return (FIB_ENTRY_SRC_FLAG_ADDED);
    }
    else if (source > best_source ) {
	/*
	 * the source is not the best. no need to update forwarding
	 */
	if (FIB_ENTRY_SRC_FLAG_ADDED & sflag)
        {
            /*
             * the source being removed still has paths
             */
            return (FIB_ENTRY_SRC_FLAG_ADDED);
        }
        else
        {
            /*
             * that was the last path from this source, check if those
             * that remain are non-inherited
             */
            if (FIB_ENTRY_SRC_FLAG_NONE == fib_entry_src_burn_only_inherited(fib_entry))
            {
                /*
                 * no more sources left. this entry is toast.
                 */
                fib_entry = fib_entry_post_flag_update_actions(fib_entry, bflags);
                fib_entry_src_action_uninstall(fib_entry);
                return (FIB_ENTRY_SRC_FLAG_NONE);
            }

            /*
             * reactivate the best source so the interposer gets restacked
             */
            fib_entry_src_action_reactivate(fib_entry, best_source);

            return (FIB_ENTRY_SRC_FLAG_ADDED);
        }
    }
    else
    {
	if (!(FIB_ENTRY_SRC_FLAG_ADDED & sflag))
	{
	    /*
	     * the source was removed. use the next best.
	     */
            return (fib_entry_source_removed(fib_entry, bflags));
	}
	else
	{
	    /*
	     * re-install the new forwarding information
	     */
	    fib_entry_src_action_reactivate(fib_entry, source);
	}
    }

    fib_entry_post_update_actions(fib_entry, source, bflags);

    /*
     * still have sources
     */
    return (FIB_ENTRY_SRC_FLAG_ADDED);
}

/**
 * fib_entry_inherit
 *
 * If the source on the cover is inheriting then push this source
 * down to the covered.
 */
void
fib_entry_inherit (fib_node_index_t cover,
                   fib_node_index_t covered)
{
    fib_entry_src_inherit(fib_entry_get(cover),
                          fib_entry_get(covered));
}

/**
 * fib_entry_delete
 *
 * The source is withdrawing all the paths it provided
 */
fib_entry_src_flag_t
fib_entry_delete (fib_node_index_t fib_entry_index,
		  fib_source_t source)
{
    return (fib_entry_special_remove(fib_entry_index, source));
}

/**
 * fib_entry_update
 *
 * The source has provided a new set of paths that will replace the old.
 */
void
fib_entry_update (fib_node_index_t fib_entry_index,
		  fib_source_t source,
		  fib_entry_flag_t flags,
		  const fib_route_path_t *paths)
{
    fib_source_t best_source;
    fib_entry_flag_t bflags;
    fib_entry_t *fib_entry;
    fib_entry_src_t *bsrc;

    fib_entry = fib_entry_get(fib_entry_index);
    ASSERT(NULL != fib_entry);

    bsrc = fib_entry_get_best_src_i(fib_entry);
    best_source = fib_entry_src_get_source(bsrc);
    bflags = fib_entry_get_flags_i(fib_entry);

    fib_entry = fib_entry_src_action_path_swap(fib_entry,
                                               source,
                                               flags,
                                               paths);

    fib_entry_source_change_w_flags(fib_entry, best_source, bflags, source);
    FIB_ENTRY_DBG(fib_entry, "update");
}


/*
 * fib_entry_cover_changed
 *
 * this entry is tracking its cover and that cover has changed.
 */
void
fib_entry_cover_changed (fib_node_index_t fib_entry_index)
{
    fib_entry_src_cover_res_t res = {
	.install = !0,
	.bw_reason = FIB_NODE_BW_REASON_FLAG_NONE,
    };
    CLIB_UNUSED(fib_source_t source);
    fib_source_t best_source;
    fib_entry_flag_t bflags;
    fib_entry_t *fib_entry;
    fib_entry_src_t *esrc;
    u32 index;

    bflags = FIB_ENTRY_FLAG_NONE;
    best_source = FIB_SOURCE_FIRST;
    fib_entry = fib_entry_get(fib_entry_index);

    fib_attached_export_cover_change(fib_entry);

    /*
     * propagate the notification to each of the added sources
     */
    index = 0;
    FOR_EACH_SRC_ADDED(fib_entry, esrc, source,
    ({
	if (0 == index)
	{
	    /*
	     * only the best source gets to set the back walk flags
	     */
	    res = fib_entry_src_action_cover_change(fib_entry, esrc);
            bflags = fib_entry_src_get_flags(esrc);
            best_source = fib_entry_src_get_source(esrc);
	}
	else
	{
	    fib_entry_src_action_cover_change(fib_entry, esrc);
	}
	index++;
    }));

    if (res.install)
    {
	fib_entry_src_action_reactivate(fib_entry,
					fib_entry_src_get_source(
					    fib_entry_get_best_src_i(fib_entry)));
        fib_entry_post_install_actions(fib_entry, best_source, bflags);
    }
    else
    {
	fib_entry_src_action_uninstall(fib_entry);
    }

    if (FIB_NODE_BW_REASON_FLAG_NONE != res.bw_reason)
    {
	/*
	 * time for walkies fido.
	 */
	fib_node_back_walk_ctx_t bw_ctx = {
	    .fnbw_reason = res.bw_reason,
        };

	fib_walk_sync(FIB_NODE_TYPE_ENTRY, fib_entry_index, &bw_ctx);
    }
    FIB_ENTRY_DBG(fib_entry, "cover-changed");
}

/*
 * fib_entry_cover_updated
 *
 * this entry is tracking its cover and that cover has been updated
 * (i.e. its forwarding information has changed).
 */
void
fib_entry_cover_updated (fib_node_index_t fib_entry_index)
{
    fib_entry_src_cover_res_t res = {
	.install = !0,
	.bw_reason = FIB_NODE_BW_REASON_FLAG_NONE,
    };
    CLIB_UNUSED(fib_source_t source);
    fib_source_t best_source;
    fib_entry_flag_t bflags;
    fib_entry_t *fib_entry;
    fib_entry_src_t *esrc;
    u32 index;

    bflags = FIB_ENTRY_FLAG_NONE;
    best_source = FIB_SOURCE_FIRST;
    fib_entry = fib_entry_get(fib_entry_index);

    fib_attached_export_cover_update(fib_entry);

    /*
     * propagate the notification to each of the added sources
     */
    index = 0;
    FOR_EACH_SRC_ADDED(fib_entry, esrc, source,
    ({
	if (0 == index)
	{
	    /*
	     * only the best source gets to set the back walk flags
	     */
	    res = fib_entry_src_action_cover_update(fib_entry, esrc);
            bflags = fib_entry_src_get_flags(esrc);
            best_source = fib_entry_src_get_source(esrc);
	}
	else
	{
	    fib_entry_src_action_cover_update(fib_entry, esrc);
	}
	index++;
    }));

    if (res.install)
    {
	fib_entry_src_action_reactivate(fib_entry,
					fib_entry_src_get_source(
					    fib_entry_get_best_src_i(fib_entry)));
        fib_entry_post_install_actions(fib_entry, best_source, bflags);
    }
    else
    {
	fib_entry_src_action_uninstall(fib_entry);
    }

    if (FIB_NODE_BW_REASON_FLAG_NONE != res.bw_reason)
    {
	/*
	 * time for walkies fido.
	 */
	fib_node_back_walk_ctx_t bw_ctx = {
	    .fnbw_reason = res.bw_reason,
        };

	fib_walk_sync(FIB_NODE_TYPE_ENTRY, fib_entry_index, &bw_ctx);
    }
    FIB_ENTRY_DBG(fib_entry, "cover-updated");
}

int
fib_entry_recursive_loop_detect (fib_node_index_t entry_index,
				 fib_node_index_t **entry_indicies)
{
    fib_entry_t *fib_entry;
    int was_looped, is_looped;

    fib_entry = fib_entry_get(entry_index);

    if (FIB_NODE_INDEX_INVALID != fib_entry->fe_parent)
    {
	fib_node_index_t *entries = *entry_indicies;

	vec_add1(entries, entry_index);
	was_looped = fib_path_list_is_looped(fib_entry->fe_parent);
	is_looped = fib_path_list_recursive_loop_detect(fib_entry->fe_parent,
							&entries);

	*entry_indicies = entries;

	if (!!was_looped != !!is_looped)
	{
	    /*
	     * re-evaluate all the entry's forwarding
	     * NOTE: this is an inplace modify
	     */
            fib_entry_delegate_type_t fdt;
            fib_entry_delegate_t *fed;

            FOR_EACH_DELEGATE_CHAIN(fib_entry, fdt, fed,
            {
                fib_entry_src_mk_lb(fib_entry,
                                    fib_entry_get_best_src_i(fib_entry),
                                    fib_entry_delegate_type_to_chain_type(fdt),
                                    &fed->fd_dpo);
	    });
	}
    }
    else
    {
	/*
	 * the entry is currently not linked to a path-list. this happens
	 * when it is this entry that is re-linking path-lists and has thus
	 * broken the loop
	 */
	is_looped = 0;
    }

    return (is_looped);
}

u32
fib_entry_get_resolving_interface (fib_node_index_t entry_index)
{
    fib_entry_t *fib_entry;

    fib_entry = fib_entry_get(entry_index);

    return (fib_path_list_get_resolving_interface(fib_entry->fe_parent));
}

fib_source_t
fib_entry_get_best_source (fib_node_index_t entry_index)
{
    fib_entry_t *fib_entry;
    fib_entry_src_t *bsrc;

    fib_entry = fib_entry_get(entry_index);

    bsrc = fib_entry_get_best_src_i(fib_entry);
    return (fib_entry_src_get_source(bsrc));
}

/**
 * Return !0 is the entry represents a host prefix
 */
int
fib_entry_is_host (fib_node_index_t fib_entry_index)
{
    return (fib_prefix_is_host(fib_entry_get_prefix(fib_entry_index)));
}

/**
 * Return !0 is the entry is resolved, i.e. will return a valid forwarding
 * chain
 */
int
fib_entry_is_resolved (fib_node_index_t fib_entry_index)
{
    fib_entry_delegate_t *fed;
    fib_entry_t *fib_entry;

    fib_entry = fib_entry_get(fib_entry_index);

    fed = fib_entry_delegate_find(fib_entry, FIB_ENTRY_DELEGATE_BFD);

    if (NULL == fed)
    {
        /*
         * no BFD tracking - consider it resolved.
         */
        return (!0);
    }
    else
    {
        /*
         * defer to the state of the BFD tracking
         */
        return (FIB_BFD_STATE_UP == fed->fd_bfd_state);
    }
}

void
fib_entry_set_flow_hash_config (fib_node_index_t fib_entry_index,
                                flow_hash_config_t hash_config)
{
    fib_entry_t *fib_entry;

    fib_entry = fib_entry_get(fib_entry_index);

    /*
     * pass the hash-config on to the load-balance object where it is cached.
     * we can ignore LBs in the delegate chains, since they will not be of the
     * correct protocol type (i.e. they are not IP)
     * There's no way, nor need, to change the hash config for MPLS.
     */
    if (dpo_id_is_valid(&fib_entry->fe_lb))
    {
        load_balance_t *lb;

        ASSERT(DPO_LOAD_BALANCE == fib_entry->fe_lb.dpoi_type);

        lb = load_balance_get(fib_entry->fe_lb.dpoi_index);

        /*
         * atomic update for packets in flight
         */
        lb->lb_hash_config = hash_config;
    }
}

u32
fib_entry_get_stats_index (fib_node_index_t fib_entry_index)
{
    fib_entry_t *fib_entry;

    fib_entry = fib_entry_get(fib_entry_index);

    return (fib_entry->fe_lb.dpoi_index);
}

static int
fib_ip4_address_compare (const ip4_address_t * a1,
                         const ip4_address_t * a2)
{
    /*
     * IP addresses are unsigned ints. the return value here needs to be signed
     * a simple subtraction won't cut it.
     * If the addresses are the same, the sort order is undefined, so phoey.
     */
    return ((clib_net_to_host_u32(a1->data_u32) >
	     clib_net_to_host_u32(a2->data_u32) ) ?
	    1 : -1);
}

static int
fib_ip6_address_compare (const ip6_address_t * a1,
                         const ip6_address_t * a2)
{
  int i;
  for (i = 0; i < ARRAY_LEN (a1->as_u16); i++)
  {
      int cmp = (clib_net_to_host_u16 (a1->as_u16[i]) -
		 clib_net_to_host_u16 (a2->as_u16[i]));
      if (cmp != 0)
	  return cmp;
  }
  return 0;
}

static int
fib_entry_cmp (fib_node_index_t fib_entry_index1,
	       fib_node_index_t fib_entry_index2)
{
    fib_entry_t *fib_entry1, *fib_entry2;
    int cmp = 0;

    fib_entry1 = fib_entry_get(fib_entry_index1);
    fib_entry2 = fib_entry_get(fib_entry_index2);

    switch (fib_entry1->fe_prefix.fp_proto)
    {
    case FIB_PROTOCOL_IP4:
        cmp = fib_ip4_address_compare(&fib_entry1->fe_prefix.fp_addr.ip4,
                                      &fib_entry2->fe_prefix.fp_addr.ip4);
        break;
    case FIB_PROTOCOL_IP6:
        cmp = fib_ip6_address_compare(&fib_entry1->fe_prefix.fp_addr.ip6,
                                      &fib_entry2->fe_prefix.fp_addr.ip6);
        break;
    case FIB_PROTOCOL_MPLS:
	cmp = (fib_entry1->fe_prefix.fp_label - fib_entry2->fe_prefix.fp_label);

	if (0 == cmp)
	{
	    cmp = (fib_entry1->fe_prefix.fp_eos - fib_entry2->fe_prefix.fp_eos);
	}
        break;
    }

    if (0 == cmp) {
	cmp = (fib_entry1->fe_prefix.fp_len - fib_entry2->fe_prefix.fp_len);
    }
    return (cmp);   
}

int
fib_entry_cmp_for_sort (void *i1, void *i2)
{
    fib_node_index_t *fib_entry_index1 = i1, *fib_entry_index2 = i2;

    return (fib_entry_cmp(*fib_entry_index1,
			  *fib_entry_index2));
}

void
fib_entry_lock (fib_node_index_t fib_entry_index)
{
    fib_entry_t *fib_entry;

    fib_entry = fib_entry_get(fib_entry_index);

    fib_node_lock(&fib_entry->fe_node);
}

void
fib_entry_unlock (fib_node_index_t fib_entry_index)
{
    fib_entry_t *fib_entry;

    fib_entry = fib_entry_get(fib_entry_index);

    fib_node_unlock(&fib_entry->fe_node);
}

void
fib_entry_module_init (void)
{
    fib_node_register_type(FIB_NODE_TYPE_ENTRY, &fib_entry_vft);
    fib_entry_logger = vlib_log_register_class("fib", "entry");

    fib_entry_track_module_init();
}

fib_route_path_t *
fib_entry_encode (fib_node_index_t fib_entry_index)
{
    fib_path_ext_list_t *ext_list;
    fib_path_encode_ctx_t ctx = {
        .rpaths = NULL,
    };
    fib_entry_t *fib_entry;
    fib_entry_src_t *bsrc;

    ext_list = NULL;
    fib_entry = fib_entry_get(fib_entry_index);
    bsrc = fib_entry_get_best_src_i(fib_entry);

    if (bsrc)
    {
	ext_list = &bsrc->fes_path_exts;
    }

    if (FIB_NODE_INDEX_INVALID != fib_entry->fe_parent)
    {
        fib_path_list_walk_w_ext(fib_entry->fe_parent,
                                 ext_list,
                                 fib_path_encode,
                                 &ctx);
    }

    return (ctx.rpaths);
}

const fib_prefix_t *
fib_entry_get_prefix (fib_node_index_t fib_entry_index)
{
    fib_entry_t *fib_entry;

    fib_entry = fib_entry_get(fib_entry_index);

    return (&fib_entry->fe_prefix);
}

u32
fib_entry_get_fib_index (fib_node_index_t fib_entry_index)
{
    fib_entry_t *fib_entry;

    fib_entry = fib_entry_get(fib_entry_index);

    return (fib_entry->fe_fib_index);
}

u32
fib_entry_pool_size (void)
{
    return (pool_elts(fib_entry_pool));
}

static clib_error_t *
show_fib_entry_command (vlib_main_t * vm,
			unformat_input_t * input,
			vlib_cli_command_t * cmd)
{
    fib_node_index_t fei;

    if (unformat (input, "%d", &fei))
    {
	/*
	 * show one in detail
	 */
	if (!pool_is_free_index(fib_entry_pool, fei))
	{
	    vlib_cli_output (vm, "%d@%U",
			     fei,
			     format_fib_entry, fei,
			     FIB_ENTRY_FORMAT_DETAIL2);
	}
	else
	{
	    vlib_cli_output (vm, "entry %d invalid", fei);
	}
    }
    else
    {
	/*
	 * show all
	 */
	vlib_cli_output (vm, "FIB Entries:");
	pool_foreach_index(fei, fib_entry_pool,
        ({
	    vlib_cli_output (vm, "%d@%U",
			     fei,
			     format_fib_entry, fei,
			     FIB_ENTRY_FORMAT_BRIEF);
	}));
    }

    return (NULL);
}

VLIB_CLI_COMMAND (show_fib_entry, static) = {
  .path = "show fib entry",
  .function = show_fib_entry_command,
  .short_help = "show fib entry",
};