/* * BIRD -- OSPF * * (c) 2000--2004 Ondrej Filip <feela@network.cz> * * Can be freely distributed and used under the terms of the GNU GPL. * */ #ifndef _BIRD_OSPF_RT_H_ #define _BIRD_OSPF_RT_H_ #define ORT_UNDEF -1 #define ORT_ROUTER 1 #define ORT_NET 0 typedef struct orta { int type; u32 options; /* * For ORT_ROUTER routes, options field are router-LSA style * options, with V,E,B bits. In OSPFv2, ASBRs from another areas * (that we know from rt-summary-lsa) have just ORTA_ASBR in * options, their real options are unknown. */ #define ORTA_ASBR OPT_RT_E #define ORTA_ABR OPT_RT_B /* * For ORT_NET routes, the field is almost unused with one * exception: ORTA_PREF for external routes means that the route is * preferred in AS external route selection according to 16.4.1. - * it is intra-area path using non-backbone area. In other words, * the forwarding address (or ASBR if forwarding address is zero) is * intra-area (type == RTS_OSPF) and its area is not a backbone. */ #define ORTA_PREF 0x80000000 u32 metric1; u32 metric2; u32 tag; u32 rid; /* Router ID of real advertising router */ struct ospf_area *oa; struct ospf_area *voa; /* Used when route is replaced in ospf_rt_sum_tr(), NULL otherwise */ struct mpnh *nhs; /* Next hops computed during SPF */ } orta; // struct ospf_iface *ifa; /* Outgoing interface */ // ip_addr nh; /* Next hop */ typedef struct ort { /* * We use fn.x0 to mark persistent rt entries, that are needed for summary * LSAs that don't have 'proper' rt entry (area networks + default to stubs) * to keep uid stable (used for LSA ID in OSPFv3 - see fibnode_to_lsaid()). * * old_* values are here to represent the last route update. old_rta * is cached (we keep reference), mainly for multipath nexthops. * old_rta == NULL means route wasn not in the last update, in that * case other old_* values are not valid. */ struct fib_node fn; orta n; u32 old_metric1, old_metric2, old_tag, old_rid; rta *old_rta; } ort; /* * Invariants for structs top_hash_entry (nodes of LSA db) * enforced by SPF calculation for final nodes (color == INSPF): * - only router, network and AS-external LSAs * - lsa.age < LSA_MAXAGE * - dist < LSINFINITY (or 2*LSINFINITY for ext-LSAs) * - nhs is non-NULL unless the node is oa->rt (calculating router itself) * - beware, nhs is not valid after SPF calculation * * Invariants for structs orta nodes of fib tables po->rtf, oa->rtr: * - nodes may be invalid (fn.type == 0), in that case other invariants don't hold * - n.metric1 may be at most a small multiple of LSINFINITY, * therefore sums do not overflow * - n.oa is always non-NULL * - n.nhs is always non-NULL with one exception - configured stubnet * nodes (in po->rtf). * - oa->rtr does not contain calculating router itself * * There are three types of nexthops in nhs fields: * - gateway nexthops (non-NULL iface, gw != IPA_NONE) * - device nexthops (non-NULL iface, gw == IPA_NONE) * - dummy vlink nexthops (NULL iface, gw == IPA_NONE) * These three types don't mix, nhs field contains either * one device, one vlink node, or one/more gateway nodes. */ void ospf_rt_spf(struct proto_ospf *po); void ospf_rt_initort(struct fib_node *fn); #endif /* _BIRD_OSPF_RT_H_ */