From d03a74933c4d5118c6e9c384f360e3de726771f9 Mon Sep 17 00:00:00 2001 From: Rafael Zalamena Date: Fri, 22 Sep 2023 12:28:38 -0300 Subject: [PATCH] lib: don't announce prefix delete for duplicates When deleting a duplicated prefix list entry don't announce the change to route map listeners, otherwise they will be removing rules that shouldn't be removed causing the prefix that still exist in the prefix-list to be not evaluated anymore. Signed-off-by: Rafael Zalamena (cherry picked from commit aed94c80967213124236ae0dfc8eebfbe9f465d5) --- lib/plist.c | 55 +++++++++++++++++++++++++++++++++++++++++++++++++---- 1 file changed, 51 insertions(+), 4 deletions(-) diff --git a/lib/plist.c b/lib/plist.c index e286a32f92..2f5827cf43 100644 --- a/lib/plist.c +++ b/lib/plist.c @@ -402,14 +402,55 @@ static void prefix_list_trie_del(struct prefix_list *plist, } } +/** + * Find duplicated prefix entry (same prefix but different entry) in prefix + * list. + */ +static bool prefix_list_entry_is_duplicated(struct prefix_list *list, + struct prefix_list_entry *entry) +{ + size_t depth, maxdepth = list->master->trie_depth; + uint8_t byte, *bytes = entry->prefix.u.val; + size_t validbits = entry->prefix.prefixlen; + struct pltrie_table *table = list->trie; + struct prefix_list_entry *pentry; + + for (depth = 0; validbits > PLC_BITS && depth < maxdepth - 1; depth++) { + byte = bytes[depth]; + if (!table->entries[byte].next_table) + return NULL; + + table = table->entries[byte].next_table; + validbits -= PLC_BITS; + } + + byte = bytes[depth]; + if (validbits > PLC_BITS) + pentry = table->entries[byte].final_chain; + else + pentry = table->entries[byte].up_chain; + + for (; pentry; pentry = pentry->next_best) { + if (pentry == entry) + continue; + if (prefix_same(&pentry->prefix, &entry->prefix)) + return true; + } + + return false; +} void prefix_list_entry_delete(struct prefix_list *plist, struct prefix_list_entry *pentry, int update_list) { + bool duplicate; + if (plist == NULL || pentry == NULL) return; + duplicate = prefix_list_entry_is_duplicated(plist, pentry); + prefix_list_trie_del(plist, pentry); if (pentry->prev) @@ -421,8 +462,10 @@ void prefix_list_entry_delete(struct prefix_list *plist, else plist->tail = pentry->prev; - route_map_notify_pentry_dependencies(plist->name, pentry, - RMAP_EVENT_PLIST_DELETED); + if (!duplicate) + route_map_notify_pentry_dependencies(plist->name, pentry, + RMAP_EVENT_PLIST_DELETED); + prefix_list_entry_free(pentry); plist->count--; @@ -557,11 +600,14 @@ static void prefix_list_entry_add(struct prefix_list *plist, void prefix_list_entry_update_start(struct prefix_list_entry *ple) { struct prefix_list *pl = ple->pl; + bool duplicate; /* Not installed, nothing to do. */ if (!ple->installed) return; + duplicate = prefix_list_entry_is_duplicated(pl, ple); + prefix_list_trie_del(pl, ple); /* List manipulation: shameless copy from `prefix_list_entry_delete`. */ @@ -574,8 +620,9 @@ void prefix_list_entry_update_start(struct prefix_list_entry *ple) else pl->tail = ple->prev; - route_map_notify_pentry_dependencies(pl->name, ple, - RMAP_EVENT_PLIST_DELETED); + if (!duplicate) + route_map_notify_pentry_dependencies(pl->name, ple, + RMAP_EVENT_PLIST_DELETED); pl->count--; route_map_notify_dependencies(pl->name, RMAP_EVENT_PLIST_DELETED); -- 2.39.5