From a987fe6b25d54b012df314bb696393f8eb8fb715 Mon Sep 17 00:00:00 2001 From: ckishimo Date: Fri, 20 Nov 2020 13:53:20 -0800 Subject: [PATCH] ospfd: fix NSSA translate-always When an ABR NSSA router is configured to be ALWAYS the translator: r22(config-router)# area 1 nssa translate-always It will advertise this condition in the type-1 LSA setting the Nt bit, taking over the translator role from r33 r22# show ip ospf We are an ABR and always an NSSA Translator. r33# show ip ospf We are an ABR, but not the NSSA Elected Translator. However when the command above is removed: r22(config-router)# no area 1 nssa translate-always the bit Nt needs to be cleared otherwise we end up with no translator in the area r22# show ip ospf We are an ABR, but not the NSSA Elected Translator. r33# show ip ospf We are an ABR, but not the NSSA Elected Translator. This PR forces the ABR to send a type-1 LSA with the Nt bit updated according to the translator role Signed-off-by: ckishimo --- ospfd/ospfd.c | 17 +++++++++++++++-- 1 file changed, 15 insertions(+), 2 deletions(-) diff --git a/ospfd/ospfd.c b/ospfd/ospfd.c index a839806720..d8be19db9a 100644 --- a/ospfd/ospfd.c +++ b/ospfd/ospfd.c @@ -1603,7 +1603,8 @@ int ospf_area_nssa_unset(struct ospf *ospf, struct in_addr area_id, int argc) OSPF_NSSA_TRANS_STABLE_DEFAULT; ospf_area_type_set(area, OSPF_AREA_DEFAULT); } else { - area->NSSATranslatorRole = OSPF_NSSA_ROLE_CANDIDATE; + ospf_area_nssa_translator_role_set(ospf, area_id, + OSPF_NSSA_ROLE_CANDIDATE); } ospf_area_check_free(ospf, area_id); @@ -1620,7 +1621,19 @@ int ospf_area_nssa_translator_role_set(struct ospf *ospf, if (area == NULL) return 0; - area->NSSATranslatorRole = role; + if (role != area->NSSATranslatorRole) { + if ((area->NSSATranslatorRole == OSPF_NSSA_ROLE_ALWAYS) + || (role == OSPF_NSSA_ROLE_ALWAYS)) { + /* RFC 3101 3.1 + * if new role is OSPF_NSSA_ROLE_ALWAYS we need to set + * Nt bit, if the role was OSPF_NSSA_ROLE_ALWAYS we need + * to clear Nt bit + */ + area->NSSATranslatorRole = role; + ospf_router_lsa_update_area(area); + } else + area->NSSATranslatorRole = role; + } return 1; } -- 2.39.5