src/vnet/fib/fib_entry_src_interpose.c - fdio/vpp - Gitiles

 /*
  * 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/drop_dpo.h>

 #include "fib_entry_src.h"
 #include "fib_entry_src_rr.h"
 #include "fib_entry_cover.h"
 #include "fib_entry.h"
 #include "fib_table.h"

 /*
  * Source initialisation Function
  */
 static void
 fib_entry_src_interpose_init (fib_entry_src_t *src)
 {
     src->u.interpose.fesi_cover = FIB_NODE_INDEX_INVALID;
     src->u.interpose.fesi_sibling = FIB_NODE_INDEX_INVALID;
 }

 /*
  * Source deinitialisation Function
  */
 static void
 fib_entry_src_interpose_deinit (fib_entry_src_t *src)
 {
     ASSERT(src->u.interpose.fesi_cover == FIB_NODE_INDEX_INVALID);

     src->u.interpose.fesi_cover = FIB_NODE_INDEX_INVALID;
     src->u.interpose.fesi_sibling = FIB_NODE_INDEX_INVALID;

     dpo_reset(&src->u.interpose.fesi_dpo);
 }

 static fib_entry_src_t *
 fib_entry_src_rr_get_next_best (const fib_entry_src_t *src,
                                 const fib_entry_t *fib_entry)
 {
     fib_entry_src_t *next_src, *best_src = NULL;
     fib_source_t source;

     FOR_EACH_SRC_ADDED(fib_entry, next_src, source,
     ({
         /*
          * skip to the next best source after this one
          */
         if (source <= src->fes_src)
         {
             continue;
         }
         else
         {
             best_src = next_src;
             break;
         }
     }));

     return (best_src);
 }

 /*
  * Source activation. Called when the source is the new best source on the entry
  */
 static int
 fib_entry_src_interpose_activate (fib_entry_src_t *src,
                                   const fib_entry_t *fib_entry)
 {
     fib_entry_src_t *best_src;
     fib_node_index_t old_pl;
     fib_entry_t *cover;

     old_pl = src->fes_pl;
     src->fes_pl = FIB_NODE_INDEX_INVALID;

     /*
      * The goal here is to find a path-list that will contribute forwarding
      * for the entry.
      * First check this entry for other sources that have a path-list
      */
     best_src = fib_entry_src_rr_get_next_best(src, fib_entry);

     if (NULL != best_src)
     {
         const fib_entry_src_vft_t *vft;

         best_src->fes_flags |= FIB_ENTRY_SRC_FLAG_CONTRIBUTING;
         vft = fib_entry_src_get_vft(best_src);
         /*
          * there is another source for this entry. activate it so it
          * can provide forwarding
          */
         if (NULL != vft->fesv_activate)
         {
             if (vft->fesv_activate(best_src, fib_entry))
             {
                 /*
                  * next best source activated ok, use its path list
                  */
                 src->fes_pl = best_src->fes_pl;
             }
         }
         else
         {
             /*
              * next best source does not require activation, use its path list
              */
             src->fes_pl = best_src->fes_pl;
         }
     }
     else
     {
         /*
          * find the covering prefix. become a dependent thereof.
          * for IP there should always be a cover, though it may be the default route.
          * For MPLS there is never a cover.
          */
         if (FIB_PROTOCOL_MPLS == fib_entry->fe_prefix.fp_proto)
         {
             src->fes_pl = fib_path_list_create_special(DPO_PROTO_MPLS,
                                                        FIB_PATH_LIST_FLAG_DROP,
                                                        NULL);
         }
         else
         {
             src->u.interpose.fesi_cover =
                 fib_table_get_less_specific(fib_entry->fe_fib_index,
                                             &fib_entry->fe_prefix);

             ASSERT(FIB_NODE_INDEX_INVALID != src->u.interpose.fesi_cover);

             cover = fib_entry_get(src->u.interpose.fesi_cover);

             src->u.interpose.fesi_sibling =
                 fib_entry_cover_track(cover, fib_entry_get_index(fib_entry));

             /*
              * if the cover is attached then install an attached-host path
              * (like an adj-fib). Otherwise inherit the forwarding from the cover
              */
             if (FIB_ENTRY_FLAG_ATTACHED & fib_entry_get_flags_i(cover))
             {
                 fib_entry_src_rr_resolve_via_connected(src, fib_entry, cover);
             }
             else
             {
                 fib_entry_src_rr_use_covers_pl(src, fib_entry, cover);
             }
         }
     }

     fib_path_list_unlock(old_pl);
     fib_path_list_lock(src->fes_pl);

     /*
      * return go for install
      */
     return (!0);
 }

 /**
  * Source Deactivate.
  * Called when the source is no longer best source on the entry
  */
 static void
 fib_entry_src_interpose_deactivate (fib_entry_src_t *src,
                                     const fib_entry_t *fib_entry)
 {
     fib_entry_t *cover;

     if (FIB_NODE_INDEX_INVALID != src->u.interpose.fesi_cover)
     {
         /*
          * remove the depednecy on the covering entry, if that's
          * what was contributing the path-list
          */
         cover = fib_entry_get(src->u.interpose.fesi_cover);
         fib_entry_cover_untrack(cover, src->u.interpose.fesi_sibling);
         src->u.interpose.fesi_cover = FIB_NODE_INDEX_INVALID;
     }
     else
     {
         fib_entry_src_t *best_src;

         best_src = fib_entry_src_rr_get_next_best(src, fib_entry);

         if (best_src)
         {
             best_src->fes_flags &= ~FIB_ENTRY_SRC_FLAG_CONTRIBUTING;
             /*
              * there is another source for this entry. activate it so it
              * can provide forwarding
              */
             FIB_ENTRY_SRC_VFT_INVOKE(best_src, fesv_deactivate,
                                      (best_src, fib_entry));
         }
     }

     fib_path_list_unlock(src->fes_pl);
     src->fes_pl = FIB_NODE_INDEX_INVALID;
     src->fes_entry_flags &= ~FIB_ENTRY_FLAGS_RR_INHERITED;
 }

 static int
 fib_entry_src_interpose_reactivate (fib_entry_src_t *src,
                                     const fib_entry_t *fib_entry)
 {
     fib_entry_src_interpose_deactivate(src, fib_entry);
     return (fib_entry_src_interpose_activate(src, fib_entry));
 }

 static fib_entry_src_cover_res_t
 fib_entry_src_interpose_cover_change (fib_entry_src_t *src,
                                       const fib_entry_t *fib_entry)
 {
     fib_entry_src_cover_res_t res = {
        .install = !0,
        .bw_reason = FIB_NODE_BW_REASON_FLAG_NONE,
     };

     if (FIB_NODE_INDEX_INVALID == src->u.interpose.fesi_cover)
     {
        /*
         * the source may be added, but it is not active
         * if it is not tracking the cover.
         */
        return (res);
     }

     /*
      * this function is called when this entry's cover has a more specific
      * entry inserted benaeth it. That does not necessarily mean that this
      * entry is covered by the new prefix. check that
      */
     if (src->u.interpose.fesi_cover !=
         fib_table_get_less_specific(fib_entry->fe_fib_index,
                                     &fib_entry->fe_prefix))
     {
        fib_entry_src_interpose_deactivate(src, fib_entry);
        fib_entry_src_interpose_activate(src, fib_entry);

        /*
         * dependent children need to re-resolve to the new forwarding info
         */
        res.bw_reason = FIB_NODE_BW_REASON_FLAG_EVALUATE;
     }
     return (res);
 }

 static void
 fib_entry_src_interpose_add (fib_entry_src_t *src,
                              const fib_entry_t *entry,
                              fib_entry_flag_t flags,
                              dpo_proto_t proto,
                              const dpo_id_t *dpo)
 {
     dpo_copy(&src->u.interpose.fesi_dpo, dpo);
 }

 static void
 fib_entry_src_interpose_remove (fib_entry_src_t *src)
 {
     dpo_reset(&src->u.interpose.fesi_dpo);
 }

 static void
 fib_entry_src_interpose_set_data (fib_entry_src_t *src,
                                   const fib_entry_t *fib_entry,
                                   const void *data)
 {
     const dpo_id_t *dpo = data;

     dpo_copy(&src->u.interpose.fesi_dpo, dpo);
 }

 /**
  * Contribute forwarding to interpose in the chain
  */
 const dpo_id_t* fib_entry_src_interpose_contribute(const fib_entry_src_t *src,
                                                    const fib_entry_t *fib_entry)
 {
     return (&src->u.interpose.fesi_dpo);
 }

 static void
 fib_entry_src_interpose_copy (const fib_entry_src_t *orig_src,
                               const fib_entry_t *fib_entry,
                               fib_entry_src_t *copy_src)
 {
     copy_src->u.interpose.fesi_cover = orig_src->u.interpose.fesi_cover;

     if (FIB_NODE_INDEX_INVALID != copy_src->u.interpose.fesi_cover)
     {
         fib_entry_t *cover;

         cover = fib_entry_get(orig_src->u.interpose.fesi_cover);
         copy_src->u.interpose.fesi_sibling =
             fib_entry_cover_track(cover, fib_entry_get_index(fib_entry));
     }

     dpo_copy(&copy_src->u.interpose.fesi_dpo,
              &orig_src->u.interpose.fesi_dpo);
 }

 static void
 fib_entry_src_interpose_flag_change (fib_entry_src_t *src,
                                      const fib_entry_t *fib_entry,
                                      fib_entry_flag_t new_flags)
 {
     if (!(new_flags & FIB_ENTRY_FLAG_INTERPOSE))
     {
         /*
          * stop tracking the source contributing forwarding
          * and reset the interposer DPO
          */
         fib_entry_src_interpose_deactivate(src, fib_entry);
         fib_entry_src_interpose_deinit(src);
     }
 }

 static u8*
 fib_entry_src_interpose_format (fib_entry_src_t *src,
                                 u8* s)
 {
     s = format(s, " cover:%d interpose:\n%U%U",
                src->u.interpose.fesi_cover,
                format_white_space, 6,
                format_dpo_id, &src->u.interpose.fesi_dpo, 8);

     return (s);
 }

 const static fib_entry_src_vft_t interpose_src_vft = {
     .fesv_init = fib_entry_src_interpose_init,
     .fesv_deinit = fib_entry_src_interpose_deinit,
     .fesv_activate = fib_entry_src_interpose_activate,
     .fesv_reactivate = fib_entry_src_interpose_reactivate,
     .fesv_deactivate = fib_entry_src_interpose_deactivate,
     .fesv_cover_change = fib_entry_src_interpose_cover_change,
     .fesv_cover_update = fib_entry_src_rr_cover_update,
     .fesv_format = fib_entry_src_interpose_format,
     .fesv_add = fib_entry_src_interpose_add,
     .fesv_remove = fib_entry_src_interpose_remove,
     .fesv_contribute_interpose = fib_entry_src_interpose_contribute,
     .fesv_set_data = fib_entry_src_interpose_set_data,
     .fesv_copy = fib_entry_src_interpose_copy,
     .fesv_flags_change = fib_entry_src_interpose_flag_change,
 };

 void
 fib_entry_src_interpose_register (void)
 {
     fib_entry_src_register(FIB_SOURCE_INTERPOSE, &interpose_src_vft);
 }
	/*
	* 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/drop_dpo.h>

	#include "fib_entry_src.h"
	#include "fib_entry_src_rr.h"
	#include "fib_entry_cover.h"
	#include "fib_entry.h"
	#include "fib_table.h"

	/*
	* Source initialisation Function
	*/
	static void
	fib_entry_src_interpose_init (fib_entry_src_t *src)
	{
	src->u.interpose.fesi_cover = FIB_NODE_INDEX_INVALID;
	src->u.interpose.fesi_sibling = FIB_NODE_INDEX_INVALID;
	}

	/*
	* Source deinitialisation Function
	*/
	static void
	fib_entry_src_interpose_deinit (fib_entry_src_t *src)
	{
	ASSERT(src->u.interpose.fesi_cover == FIB_NODE_INDEX_INVALID);

	src->u.interpose.fesi_cover = FIB_NODE_INDEX_INVALID;
	src->u.interpose.fesi_sibling = FIB_NODE_INDEX_INVALID;

	dpo_reset(&src->u.interpose.fesi_dpo);
	}

	static fib_entry_src_t *
	fib_entry_src_rr_get_next_best (const fib_entry_src_t *src,
	const fib_entry_t *fib_entry)
	{
	fib_entry_src_t next_src, best_src = NULL;
	fib_source_t source;

	FOR_EACH_SRC_ADDED(fib_entry, next_src, source,
	({
	/*
	* skip to the next best source after this one
	*/
	if (source <= src->fes_src)
	{
	continue;
	}
	else
	{
	best_src = next_src;
	break;
	}
	}));

	return (best_src);
	}

	/*
	* Source activation. Called when the source is the new best source on the entry
	*/
	static int
	fib_entry_src_interpose_activate (fib_entry_src_t *src,
	const fib_entry_t *fib_entry)
	{
	fib_entry_src_t *best_src;
	fib_node_index_t old_pl;
	fib_entry_t *cover;

	old_pl = src->fes_pl;
	src->fes_pl = FIB_NODE_INDEX_INVALID;

	/*
	* The goal here is to find a path-list that will contribute forwarding
	* for the entry.
	* First check this entry for other sources that have a path-list
	*/
	best_src = fib_entry_src_rr_get_next_best(src, fib_entry);

	if (NULL != best_src)
	{
	const fib_entry_src_vft_t *vft;

	best_src->fes_flags \|= FIB_ENTRY_SRC_FLAG_CONTRIBUTING;
	vft = fib_entry_src_get_vft(best_src);
	/*
	* there is another source for this entry. activate it so it
	* can provide forwarding
	*/
	if (NULL != vft->fesv_activate)
	{
	if (vft->fesv_activate(best_src, fib_entry))
	{
	/*
	* next best source activated ok, use its path list
	*/
	src->fes_pl = best_src->fes_pl;
	}
	}
	else
	{
	/*
	* next best source does not require activation, use its path list
	*/
	src->fes_pl = best_src->fes_pl;
	}
	}
	else
	{
	/*
	* find the covering prefix. become a dependent thereof.
	* for IP there should always be a cover, though it may be the default route.
	* For MPLS there is never a cover.
	*/
	if (FIB_PROTOCOL_MPLS == fib_entry->fe_prefix.fp_proto)
	{
	src->fes_pl = fib_path_list_create_special(DPO_PROTO_MPLS,
	FIB_PATH_LIST_FLAG_DROP,
	NULL);
	}
	else
	{
	src->u.interpose.fesi_cover =
	fib_table_get_less_specific(fib_entry->fe_fib_index,
	&fib_entry->fe_prefix);

	ASSERT(FIB_NODE_INDEX_INVALID != src->u.interpose.fesi_cover);

	cover = fib_entry_get(src->u.interpose.fesi_cover);

	src->u.interpose.fesi_sibling =
	fib_entry_cover_track(cover, fib_entry_get_index(fib_entry));

	/*
	* if the cover is attached then install an attached-host path
	* (like an adj-fib). Otherwise inherit the forwarding from the cover
	*/
	if (FIB_ENTRY_FLAG_ATTACHED & fib_entry_get_flags_i(cover))
	{
	fib_entry_src_rr_resolve_via_connected(src, fib_entry, cover);
	}
	else
	{
	fib_entry_src_rr_use_covers_pl(src, fib_entry, cover);
	}
	}
	}

	fib_path_list_unlock(old_pl);
	fib_path_list_lock(src->fes_pl);

	/*
	* return go for install
	*/
	return (!0);
	}

	/**
	* Source Deactivate.
	* Called when the source is no longer best source on the entry
	*/
	static void
	fib_entry_src_interpose_deactivate (fib_entry_src_t *src,
	const fib_entry_t *fib_entry)
	{
	fib_entry_t *cover;

	if (FIB_NODE_INDEX_INVALID != src->u.interpose.fesi_cover)
	{
	/*
	* remove the depednecy on the covering entry, if that's
	* what was contributing the path-list
	*/
	cover = fib_entry_get(src->u.interpose.fesi_cover);
	fib_entry_cover_untrack(cover, src->u.interpose.fesi_sibling);
	src->u.interpose.fesi_cover = FIB_NODE_INDEX_INVALID;
	}
	else
	{
	fib_entry_src_t *best_src;

	best_src = fib_entry_src_rr_get_next_best(src, fib_entry);

	if (best_src)
	{
	best_src->fes_flags &= ~FIB_ENTRY_SRC_FLAG_CONTRIBUTING;
	/*
	* there is another source for this entry. activate it so it
	* can provide forwarding
	*/
	FIB_ENTRY_SRC_VFT_INVOKE(best_src, fesv_deactivate,
	(best_src, fib_entry));
	}
	}

	fib_path_list_unlock(src->fes_pl);
	src->fes_pl = FIB_NODE_INDEX_INVALID;
	src->fes_entry_flags &= ~FIB_ENTRY_FLAGS_RR_INHERITED;
	}

	static int
	fib_entry_src_interpose_reactivate (fib_entry_src_t *src,
	const fib_entry_t *fib_entry)
	{
	fib_entry_src_interpose_deactivate(src, fib_entry);
	return (fib_entry_src_interpose_activate(src, fib_entry));
	}

	static fib_entry_src_cover_res_t
	fib_entry_src_interpose_cover_change (fib_entry_src_t *src,
	const fib_entry_t *fib_entry)
	{
	fib_entry_src_cover_res_t res = {
	.install = !0,
	.bw_reason = FIB_NODE_BW_REASON_FLAG_NONE,
	};

	if (FIB_NODE_INDEX_INVALID == src->u.interpose.fesi_cover)
	{
	/*
	* the source may be added, but it is not active
	* if it is not tracking the cover.
	*/
	return (res);
	}

	/*
	* this function is called when this entry's cover has a more specific
	* entry inserted benaeth it. That does not necessarily mean that this
	* entry is covered by the new prefix. check that
	*/
	if (src->u.interpose.fesi_cover !=
	fib_table_get_less_specific(fib_entry->fe_fib_index,
	&fib_entry->fe_prefix))
	{
	fib_entry_src_interpose_deactivate(src, fib_entry);
	fib_entry_src_interpose_activate(src, fib_entry);

	/*
	* dependent children need to re-resolve to the new forwarding info
	*/
	res.bw_reason = FIB_NODE_BW_REASON_FLAG_EVALUATE;
	}
	return (res);
	}

	static void
	fib_entry_src_interpose_add (fib_entry_src_t *src,
	const fib_entry_t *entry,
	fib_entry_flag_t flags,
	dpo_proto_t proto,
	const dpo_id_t *dpo)
	{
	dpo_copy(&src->u.interpose.fesi_dpo, dpo);
	}

	static void
	fib_entry_src_interpose_remove (fib_entry_src_t *src)
	{
	dpo_reset(&src->u.interpose.fesi_dpo);
	}

	static void
	fib_entry_src_interpose_set_data (fib_entry_src_t *src,
	const fib_entry_t *fib_entry,
	const void *data)
	{
	const dpo_id_t *dpo = data;

	dpo_copy(&src->u.interpose.fesi_dpo, dpo);
	}

	/**
	* Contribute forwarding to interpose in the chain
	*/
	const dpo_id_t* fib_entry_src_interpose_contribute(const fib_entry_src_t *src,
	const fib_entry_t *fib_entry)
	{
	return (&src->u.interpose.fesi_dpo);
	}

	static void
	fib_entry_src_interpose_copy (const fib_entry_src_t *orig_src,
	const fib_entry_t *fib_entry,
	fib_entry_src_t *copy_src)
	{
	copy_src->u.interpose.fesi_cover = orig_src->u.interpose.fesi_cover;

	if (FIB_NODE_INDEX_INVALID != copy_src->u.interpose.fesi_cover)
	{
	fib_entry_t *cover;

	cover = fib_entry_get(orig_src->u.interpose.fesi_cover);
	copy_src->u.interpose.fesi_sibling =
	fib_entry_cover_track(cover, fib_entry_get_index(fib_entry));
	}

	dpo_copy(&copy_src->u.interpose.fesi_dpo,
	&orig_src->u.interpose.fesi_dpo);
	}

	static void
	fib_entry_src_interpose_flag_change (fib_entry_src_t *src,
	const fib_entry_t *fib_entry,
	fib_entry_flag_t new_flags)
	{
	if (!(new_flags & FIB_ENTRY_FLAG_INTERPOSE))
	{
	/*
	* stop tracking the source contributing forwarding
	* and reset the interposer DPO
	*/
	fib_entry_src_interpose_deactivate(src, fib_entry);
	fib_entry_src_interpose_deinit(src);
	}
	}

	static u8*
	fib_entry_src_interpose_format (fib_entry_src_t *src,
	u8* s)
	{
	s = format(s, " cover:%d interpose:\n%U%U",
	src->u.interpose.fesi_cover,
	format_white_space, 6,
	format_dpo_id, &src->u.interpose.fesi_dpo, 8);

	return (s);
	}

	const static fib_entry_src_vft_t interpose_src_vft = {
	.fesv_init = fib_entry_src_interpose_init,
	.fesv_deinit = fib_entry_src_interpose_deinit,
	.fesv_activate = fib_entry_src_interpose_activate,
	.fesv_reactivate = fib_entry_src_interpose_reactivate,
	.fesv_deactivate = fib_entry_src_interpose_deactivate,
	.fesv_cover_change = fib_entry_src_interpose_cover_change,
	.fesv_cover_update = fib_entry_src_rr_cover_update,
	.fesv_format = fib_entry_src_interpose_format,
	.fesv_add = fib_entry_src_interpose_add,
	.fesv_remove = fib_entry_src_interpose_remove,
	.fesv_contribute_interpose = fib_entry_src_interpose_contribute,
	.fesv_set_data = fib_entry_src_interpose_set_data,
	.fesv_copy = fib_entry_src_interpose_copy,
	.fesv_flags_change = fib_entry_src_interpose_flag_change,
	};

	void
	fib_entry_src_interpose_register (void)
	{
	fib_entry_src_register(FIB_SOURCE_INTERPOSE, &interpose_src_vft);
	}