/* * 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 "fib_entry.h" #include "fib_entry_src.h" #include "fib_path_list.h" #include "fib_table.h" #include "fib_entry_cover.h" #include "fib_attached_export.h" #include "fib_path_ext.h" /** * Source initialisation Function */ static void fib_entry_src_adj_init (fib_entry_src_t *src) { src->u.adj.fesa_cover = FIB_NODE_INDEX_INVALID; src->u.adj.fesa_sibling = FIB_NODE_INDEX_INVALID; } static void fib_entry_src_adj_path_add (fib_entry_src_t *src, const fib_entry_t *entry, fib_path_list_flags_t pl_flags, const fib_route_path_t *paths) { const fib_route_path_t *rpath; if (FIB_NODE_INDEX_INVALID == src->fes_pl) { src->fes_pl = fib_path_list_create(pl_flags, paths); } else { src->fes_pl = fib_path_list_copy_and_path_add(src->fes_pl, pl_flags, paths); } /* * resolve the existing extensions */ fib_path_ext_list_resolve(&src->fes_path_exts, src->fes_pl); /* * and new extensions */ vec_foreach(rpath, paths) { fib_path_ext_list_insert(&src->fes_path_exts, src->fes_pl, FIB_PATH_EXT_ADJ, rpath); } } static void fib_entry_src_adj_path_remove (fib_entry_src_t *src, fib_path_list_flags_t pl_flags, const fib_route_path_t *rpaths) { const fib_route_path_t *rpath; if (FIB_NODE_INDEX_INVALID != src->fes_pl) { src->fes_pl = fib_path_list_copy_and_path_remove(src->fes_pl, pl_flags, rpaths); } /* * remove the path-extension for the path */ vec_foreach(rpath, rpaths) { fib_path_ext_list_remove(&src->fes_path_exts, FIB_PATH_EXT_ADJ, rpath); }; /* * resolve the remaining extensions */ fib_path_ext_list_resolve(&src->fes_path_exts, src->fes_pl); } static void fib_entry_src_adj_path_swap (fib_entry_src_t *src, const fib_entry_t *entry, fib_path_list_flags_t pl_flags, const fib_route_path_t *paths) { const fib_route_path_t *rpath; /* * flush all the old extensions before we create a brand new path-list */ fib_path_ext_list_flush(&src->fes_path_exts); src->fes_pl = fib_path_list_create(pl_flags, paths); /* * and new extensions */ vec_foreach(rpath, paths) { fib_path_ext_list_push_back(&src->fes_path_exts, src->fes_pl, FIB_PATH_EXT_ADJ, rpath); } } static void fib_entry_src_adj_remove (fib_entry_src_t *src) { src->fes_pl = FIB_NODE_INDEX_INVALID; } /* * Add a path-extension indicating whether this path is resolved, * because it passed the refinement check */ static void fib_enty_src_adj_update_path_ext (fib_entry_src_t *src, fib_node_index_t path_index, fib_path_ext_adj_flags_t flags) { fib_path_ext_t *path_ext; path_ext = fib_path_ext_list_find_by_path_index(&src->fes_path_exts, path_index); if (NULL != path_ext) { path_ext->fpe_adj_flags = flags; } else { ASSERT(!"no path extension"); } } typedef struct fib_entry_src_path_list_walk_cxt_t_ { fib_entry_src_t *src; u32 cover_itf; fib_path_ext_adj_flags_t flags; } fib_entry_src_path_list_walk_cxt_t; static fib_path_list_walk_rc_t fib_entry_src_adj_path_list_walk (fib_node_index_t pl_index, fib_node_index_t path_index, void *arg) { fib_entry_src_path_list_walk_cxt_t *ctx; u32 adj_itf; ctx = arg; adj_itf = fib_path_get_resolving_interface(path_index); if (ctx->cover_itf == adj_itf) { fib_enty_src_adj_update_path_ext(ctx->src, path_index, FIB_PATH_EXT_ADJ_FLAG_REFINES_COVER); ctx->flags |= FIB_PATH_EXT_ADJ_FLAG_REFINES_COVER; } else { /* * if the interface the adj is on is unnumbered to the * cover's, then allow that too. */ vnet_sw_interface_t *swif; swif = vnet_get_sw_interface (vnet_get_main(), adj_itf); if (swif->flags & VNET_SW_INTERFACE_FLAG_UNNUMBERED && ctx->cover_itf == swif->unnumbered_sw_if_index) { fib_enty_src_adj_update_path_ext(ctx->src, path_index, FIB_PATH_EXT_ADJ_FLAG_REFINES_COVER); ctx->flags |= FIB_PATH_EXT_ADJ_FLAG_REFINES_COVER; } else { fib_enty_src_adj_update_path_ext(ctx->src, path_index, FIB_PATH_EXT_ADJ_FLAG_NONE); } } return (FIB_PATH_LIST_WALK_CONTINUE); } static int fib_entry_src_adj_activate (fib_entry_src_t *src, const fib_entry_t *fib_entry) { fib_entry_t *cover; /* * find the covering prefix. become a dependent thereof. * there should always be a cover, though it may be the default route. */ src->u.adj.fesa_cover = fib_table_get_less_specific(fib_entry->fe_fib_index, &fib_entry->fe_prefix); ASSERT(FIB_NODE_INDEX_INVALID != src->u.adj.fesa_cover); ASSERT(fib_entry_get_index(fib_entry) != src->u.adj.fesa_cover); cover = fib_entry_get(src->u.adj.fesa_cover); ASSERT(cover != fib_entry); src->u.adj.fesa_sibling = fib_entry_cover_track(cover, fib_entry_get_index(fib_entry)); /* * if the cover is attached on the same interface as this adj source then * install the FIB entry via the adj. otherwise install a drop. * This prevents ARP/ND entries that on interface X that do not belong * on X's subnet from being added to the FIB. To do so would allow * nefarious gratuitous ARP requests from attracting traffic to the sender. * * and yes, I really do mean attached and not connected. * this abomination; * ip route add 10.0.0.0/24 Eth0 * is attached. and we want adj-fibs to install on Eth0. */ if (FIB_ENTRY_FLAG_ATTACHED & fib_entry_get_flags_i(cover) || (FIB_ENTRY_FLAG_ATTACHED & fib_entry_get_flags_for_source(src->u.adj.fesa_cover, FIB_SOURCE_INTERFACE))) { fib_entry_src_path_list_walk_cxt_t ctx = { .cover_itf = fib_entry_get_resolving_interface(src->u.adj.fesa_cover), .flags = FIB_PATH_EXT_ADJ_FLAG_NONE, .src = src, }; fib_path_list_walk(src->fes_pl, fib_entry_src_adj_path_list_walk, &ctx); /* * active the entry is one of the paths refines the cover. */ return (FIB_PATH_EXT_ADJ_FLAG_REFINES_COVER & ctx.flags); } return (0); } /* * Source re-activate. * Called when the source path lit has changed and the source is still * the best source */ static int fib_entry_src_adj_reactivate (fib_entry_src_t *src, const fib_entry_t *fib_entry) { fib_entry_src_path_list_walk_cxt_t ctx = { .cover_itf = fib_entry_get_resolving_interface(src->u.adj.fesa_cover), .flags = FIB_PATH_EXT_ADJ_FLAG_NONE, .src = src, }; fib_path_list_walk(src->fes_pl, fib_entry_src_adj_path_list_walk, &ctx); return (FIB_PATH_EXT_ADJ_FLAG_REFINES_COVER & ctx.flags); } /* * Source Deactivate. * Called when the source is no longer best source on the entry */ static void fib_entry_src_adj_deactivate (fib_entry_src_t *src, const fib_entry_t *fib_entry) { fib_entry_t *cover; /* * remove the dependency on the covering entry */ if (FIB_NODE_INDEX_INVALID == src->u.adj.fesa_cover) { /* * this is the case if the entry is in the non-forwarding trie */ return; } cover = fib_entry_get(src->u.adj.fesa_cover); fib_entry_cover_untrack(cover, src->u.adj.fesa_sibling); /* * tell the cover this entry no longer needs exporting */ fib_attached_export_covered_removed(cover, fib_entry_get_index(fib_entry)); src->u.adj.fesa_cover = FIB_NODE_INDEX_INVALID; } static u8* fib_entry_src_adj_format (fib_entry_src_t *src, u8* s) { return (format(s, " cover:%d", src->u.adj.fesa_cover)); } static void fib_entry_src_adj_installed (fib_entry_src_t *src, const fib_entry_t *fib_entry) { /* * The adj source now rules! poke our cover to get exported */ fib_entry_t *cover; ASSERT(FIB_NODE_INDEX_INVALID != src->u.adj.fesa_cover); cover = fib_entry_get(src->u.adj.fesa_cover); fib_attached_export_covered_added(cover, fib_entry_get_index(fib_entry)); } static fib_entry_src_cover_res_t fib_entry_src_adj_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, }; fib_entry_src_adj_deactivate(src, fib_entry); res.install = fib_entry_src_adj_activate(src, fib_entry); if (res.install) { /* * ADJ fib can install */ res.bw_reason = FIB_NODE_BW_REASON_FLAG_EVALUATE; } FIB_ENTRY_DBG(fib_entry, "adj-src-cover-changed"); return (res); } /* * fib_entry_src_adj_cover_update */ static fib_entry_src_cover_res_t fib_entry_src_adj_cover_update (fib_entry_src_t *src, const fib_entry_t *fib_entry) { /* * the cover has updated, i.e. its forwarding or flags * have changed. don't deactivate/activate here, since this * prefix is updated during the covers walk. */ fib_entry_src_cover_res_t res = { .install = 0, .bw_reason = FIB_NODE_BW_REASON_FLAG_NONE, }; fib_entry_t *cover; /* * If there is no cover, then the source is not active and we can ignore * this update */ if (FIB_NODE_INDEX_INVALID != src->u.adj.fesa_cover) { cover = fib_entry_get(src->u.adj.fesa_cover); res.install = (FIB_ENTRY_FLAG_ATTACHED & fib_entry_get_flags_i(cover)); FIB_ENTRY_DBG(fib_entry, "adj-src-cover-updated"); } return (res); } const static fib_entry_src_vft_t adj_src_vft = { .fesv_init = fib_entry_src_adj_init, .fesv_path_swap = fib_entry_src_adj_path_swap, .fesv_path_add = fib_entry_src_adj_path_add, .fesv_path_remove = fib_entry_src_adj_path_remove, .fesv_remove = fib_entry_src_adj_remove, .fesv_activate = fib_entry_src_adj_activate, .fesv_deactivate = fib_entry_src_adj_deactivate, .fesv_reactivate = fib_entry_src_adj_reactivate, .fesv_format = fib_entry_src_adj_format, .fesv_installed = fib_entry_src_adj_installed, .fesv_cover_change = fib_entry_src_adj_cover_change, .fesv_cover_update = fib_entry_src_adj_cover_update, }; void fib_entry_src_adj_register (void) { fib_entry_src_register(FIB_SOURCE_ADJ, &adj_src_vft); }