diff options
Diffstat (limited to 'src/vnet/fib/fib_entry_src_adj.c')
| -rw-r--r-- | src/vnet/fib/fib_entry_src_adj.c | 207 |
1 files changed, 207 insertions, 0 deletions
diff --git a/src/vnet/fib/fib_entry_src_adj.c b/src/vnet/fib/fib_entry_src_adj.c new file mode 100644 index 00000000000..64f82a73e07 --- /dev/null +++ b/src/vnet/fib/fib_entry_src_adj.c @@ -0,0 +1,207 @@ +/* + * 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" + +/** + * Source initialisation Function + */ +static void +fib_entry_src_adj_init (fib_entry_src_t *src) +{ + src->adj.fesa_cover = FIB_NODE_INDEX_INVALID; + src->adj.fesa_sibling = FIB_NODE_INDEX_INVALID; +} + +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) +{ + src->fes_pl = fib_path_list_create(pl_flags, paths); +} + +static void +fib_entry_src_adj_remove (fib_entry_src_t *src) +{ + src->fes_pl = FIB_NODE_INDEX_INVALID; +} + + +/* + * Source activate. + * Called when the source is teh new longer best source on the entry + */ +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->adj.fesa_cover = fib_table_get_less_specific(fib_entry->fe_fib_index, + &fib_entry->fe_prefix); + + ASSERT(FIB_NODE_INDEX_INVALID != src->adj.fesa_cover); + ASSERT(fib_entry_get_index(fib_entry) != src->adj.fesa_cover); + + cover = fib_entry_get(src->adj.fesa_cover); + + ASSERT(cover != fib_entry); + + src->adj.fesa_sibling = + fib_entry_cover_track(cover, + fib_entry_get_index(fib_entry)); + + /* + * if the ocver is attached then this adj source entry can install, + * 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. + */ + return (FIB_ENTRY_FLAG_ATTACHED & fib_entry_get_flags_i(cover)); +} + +/* + * 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 depednecy on the covering entry + */ + ASSERT(FIB_NODE_INDEX_INVALID != src->adj.fesa_cover); + cover = fib_entry_get(src->adj.fesa_cover); + + fib_entry_cover_untrack(cover, src->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->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->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->adj.fesa_cover); + cover = fib_entry_get(src->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; + } + + 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. do'nt decativate/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; + + ASSERT(FIB_NODE_INDEX_INVALID != src->adj.fesa_cover); + + cover = fib_entry_get(src->adj.fesa_cover); + + res.install = (FIB_ENTRY_FLAG_ATTACHED & fib_entry_get_flags_i(cover)); + + 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_remove = fib_entry_src_adj_remove, + .fesv_activate = fib_entry_src_adj_activate, + .fesv_deactivate = fib_entry_src_adj_deactivate, + .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); +} |